* Cancer-causing virus strikes genetically vulnerable horses

Sarcoid skin tumors are the most common form of cancer in horses, but little is known about why the papillomavirus behind them strikes some horses and not others. A new study by an international research group led by scientists at the Baker Institute for Animal Health at Cornell’s College of Veterinary Medicine shows genetic differences in immune function between horses partly accounts for these differences. The study, published in the International Journal of Cancer, mirrors findings in humans, as some people have a genetic susceptibility to human papillomavirus, which can cause cervical and other cancers.

“Many therapies have been proposed as the ‘best’ treatment for sarcoids,” says Dr. Doug Antczak, the Dorothy Havemeyer McConville Professor of Equine Medicine, who led the study. In some horses, tumors develop as small bumps under the skin or as scaly lesions that easily can be removed by a veterinarian, but in other horses the problem becomes much more serious. Surgery, cryotherapy (freezing the tissue), laser treatment, injecting the tumors with drugs to kill the cells, radiation treatment and immunotherapy have all been shown to cure these recalcitrant tumors, “but some tumors tend to recur no matter what treatment is used, and there is no universal consensus on a uniformly successful therapy,” says Antczak.

Antczak says it’s been thought for years that bovine papillomavirus (BPV) is the most likely culprit behind sarcoid tumors. Recent work from Europe suggests variants of the BPV have become adapted to horses and are probably the cause of most sarcoids.

With a grant from the Morris Animal Foundation, Antczak, his collaborators Samantha Brooks and Ann Staiger from the University of Florida, and the rest of the team applied a genomewide association study to compare the genetic makeup of horses with and without sarcoid tumors at more than 50,000 sites in the equine genome. They studied 82 sarcoid-bearing horses from the U.S. and United Kingdom and 272 carefully matched controls that did not have sarcoids. They found regions on chromosomes 20 and 22 that tended to be different in horses diagnosed with sarcoids, evidence that a horse’s genes determine, in part, how susceptible it is to sarcoids.

“This is an example of more complicated genetics — multigene susceptibility,” says Antczak. “More than one genetic region is associated with susceptibility to sarcoids, and they don’t completely determine whether or not a horse will develop the disease once it’s exposed to BPV.”

This genetic link implicates the immune system in sarcoid susceptibility. The region of chromosome 20 associated with sarcoid development is within a portion of the genome responsible for immune function called the Major Histocompatibility Complex (MHC) class II region. The MHC type associated with sarcoid susceptibility is very rare among Standardbred horses, a fact that may explain why sarcoid is diagnosed so rarely in this breed.

This complex mix of virus, host genes and tumor development may have relevance to a related human condition. Tumors caused by human papillomaviruses account for more than 5 percent of cancer cases worldwide. In women with cervical cancer, an association with the MHC class II region has also been shown.

“That should make a light bulb go off,” Antczak says. “It suggests there’s a common mechanism in both species for susceptibility to tumor progression that may involve subversion of the host immune response. By studying this phenomenon in horses you can learn about human cancer and vice versa.”  Science Daily  Original web page at Science Daily


Developing ways to study influenza D virus

Although a new influenza virus, now called influenza D, was discovered first in pigs, researchers found it was more common in cattle. However, further research has identified antibodies to the virus in small ruminants, but not in poultry.

To identify exposure to the virus, South Dakota State University doctoral student Chithra Sreenivasan tests blood samples for influenza D antibodies. Working with the Minnesota Poultry Testing Lab, she found no evidence of the new influenza strain in poultry; however, she did find antibodies to the virus in sheep and goats from the Midwest through blood samples archived at Washington State University.

Sreenivasan co-authored a paper on those findings that was published in the international journal Veterinary Microbiology last year. In ongoing work, she and her colleagues have also identified antibodies in horses. For her work, she has received the Joseph P. Nelson Graduate Scholarship Award that recognizes original scientifc research.

“The virus has not been shown to be pathogenic in humans. No one should be afraid of this,” professor Radhey Kaushik said. SDSU alumnus Ben Hause, now a research assistant professor at Kansas State University, discovered the virus, which he identified and characterized as part of his doctoral work under tutelage of his research adviser, professor Feng Li.

Li and Kaushik secured a National Institutes of Health grant for nearly $400,000 to continue this work. Both faculty members have joint appointments in the biology and microbiology and veterinary and biomedical sciences departments at South Dakota State.

Ultimately, the goal is to determine whether the virus can cause problems in humans, he explained. “If the virus can undergo reassortment in combination with a closely related human influenza virus, it may be able to form a new strain that could pose more of a threat to humans.”

Using the bovine Influenza D strain, Sreenivasan proved that the guinea pig could be used as an animal model to study the virus. Though guinea pigs showed no symptoms, she successfully isolated antigens in tracheal and lung tissues. In addition, her research showed the virus is spread only through direct contact. Those results were published in the Journal of Virology, with Sreenivasan as the first author of the article.

Her current study uses the guinea pig model to compare virulence among bovine and swine Influenza D strains and human influenza C. She has just begun analyzing the data. Influenza D has about 50 percent similarity to human influenza C, Sreenivasan explained.

“Human C affects mostly children,” she said, noting that the most common symptom is a runny nose. “It’s not a serious disease. We all have some antibodies because we were infected as children.”

In addition, she is developing a way to study the virus in living cells — trachea and lung epithelial cells from swine and cattle. “I isolate the cells and allow them to grow and then infect them to study the genetic and biologic characteristics,” she said.

Thus far, she’s completed the swine cell cultures and will now begin work on bovine cells. Using the in vitro culturing system, Sreenivasan said, “We will see how the virus attaches and what the receptors are.”   Science Daily Original web page at Science Daily


* ‘Camera pill’ to examine horses

Veterinary and engineering researchers at the University of Saskatchewan (U of S) have teamed up to harness imaging technology to fill in a blank area in animal health — what goes on in a horse’s gut?

“Whenever I talk to students about the horse abdomen, I put up a picture of a horse and put a big question mark in the middle,” said veterinary researcher Dr. Julia Montgomery in the U of S Western College of Veterinary Medicine. Montgomery worked with equine surgeon Dr. Joe Bracamonte and Khan Wahid, a specialist in health informatics and imaging in the College of Engineering. The team used an endoscopy capsule about the size and shape of a vitamin pill — a sort of “mini submarine” with a camera — to have a look inside a horse.

“This is really a cool way to look at the entire small intestine,” Montgomery said, explaining the only other ways are exploratory surgery or laparoscopy, which uses a thin, lighted tube inserted through an incision. Neither allows a view from inside. Veterinarians also can use an endoscope — basically a camera on the end of a thin cable — to look as far as the horse’s stomach, and a rectal exam to have a look from the other end.

Montgomery explained that capsule endoscopy offers a powerful new tool to diagnose diseases such as inflammatory bowel disease and cancer, or to check surgical sites. Researchers could use it to see how well drugs to stimulate bowel action are working, or to answer basic questions such as determining what “normal” small intestine function looks like.

Wahid has long worked with endoscopy capsule technology for humans and has even patented algorithms and data compression technology for their improved performance. The “camera pills” have been in use for human medicine for some time, he explained, but have yet to be applied in equine health. “We thought, ‘why not try it for veterinary medicine?'” Wahid said. On March 1, they did just that, administering the capsule through a stomach tube directly to the horse’s stomach. For the next eight hours, the capsule and its camera made its way through the horse’s small intestine, offering a continuous picture of what was going on inside.

The team plans to run more tests in the next few months on different horses to gather more data. With this in hand, they plan to pursue funding to further develop equine capsule endoscopy.

“From the engineering side, we can now look at good data,” Wahid explained. “Once we know more about the requirements, we can make it really customizable, a pill specific to the horse.”   Science Daily  Original web page at Science Daily


Horses can read human emotions

For the first time horses have been shown to be able to distinguish between angry and happy human facial expressions.

Psychologists studied how 28 horses reacted to seeing photographs of positive versus negative human facial expressions. When viewing angry faces, horses looked more with their left eye, a behaviour associated with perceiving negative stimuli. Their heart rate also increased more quickly and they showed more stress-related behaviours. The study, published today (10 February) in Biology Letters, concludes that this response indicates that the horses had a functionally relevant understanding of the angry faces they were seeing. The effect of facial expressions on heart rate has not been seen before in interactions between animals and humans.

Amy Smith, a doctoral student in the Mammal Vocal Communication and Cognition Research Group at the University of Sussex who co-led the research, said: “What’s really interesting about this research is that it shows that horses have the ability to read emotions across the species barrier. We have known for a long time that horses are a socially sophisticated species but this is the first time we have seen that they can distinguish between positive and negative human facial expressions.”

“The reaction to the angry facial expressions was particularly clear — there was a quicker increase in their heart rate, and the horses moved their heads to look at the angry faces with their left eye.” Research shows that many species view negative events with their left eye due to the right brain hemisphere’s specialisation for processing threatening stimuli (information from the left eye is processed in the right hemisphere).

Amy continued: “It’s interesting to note that the horses had a strong reaction to the negative expressions but less so to the positive. This may be because it is particularly important for animals to recognise threats in their environment. In this context, recognising angry faces may act as a warning system, allowing horses to anticipate negative human behaviour such as rough handling.”

A tendency for viewing negative human facial expressions with the left eye specifically has also been documented in dogs.

Professor Karen McComb, a co-lead author of the research, said: “There are several possible explanations for our findings. Horses may have adapted an ancestral ability for reading emotional cues in other horses to respond appropriately to human facial expressions during their co-evolution. Alternatively, individual horses may have learned to interpret human expressions during their own lifetime. What’s interesting is that accurate assessment of a negative emotion is possible across the species barrier despite the dramatic difference in facial morphology between horses and humans.”

“Emotional awareness is likely to be very important in highly social species like horses — and our ongoing research is examining the relationship between a range of emotional skills and social behaviour.”

The horses were recruited from five riding or livery stables in Sussex and Surrey, UK, between April 2014 and February 2015. They were shown happy and angry photographs of two unfamiliar male faces. The experimental tests examined the horses’ spontaneous reactions to the photos, with no prior training, and the experimenters were not able to see which photographs they were displaying so they could not inadvertently influence the horses.  Science Daily  Original web page at Science Daily


Simulator-based training in veterinary medicine

Simulator-based training of students at Vetmeduni Vienna has been part of the curriculum since 2012. The Skills Lab is a simulated veterinary practice in which students have the chance to train a variety of veterinary interventions in a near-realistic setup on animal dummies.

But is simulator-based training really as efficient as training on live animals? Christina Nagel, Christine Aurich and their team from Vetmeduni Vienna’s Centre for Artificial Insemination and Embryo Transfer have now analysed for the first time the efficiency of simulator-based training in large animal gynaecology.

Twenty-five third-year veterinary students participated in the study on gynaecological examination of horse mares. Students were randomly allocated to three groups and taught palpation and ultrasonography of the equine genital tract in different ways. Group 1 trained four times on the simulator, consisting of a plastic box shaped like the back-end of a horse with exchangeable rubber genital organs. Group 2 students were trained four times on teaching horses whereas group 3 had only one training session on horse mares.

Two weeks after the last training session, the researchers tested the learning outcomes. All students were asked to examine a horse mare and to make a diagnosis. Students who had trained four times on horses scored best with regard to a correct diagnosis. Students who had been trained only once on horses had the worst results and those trained solely on the simulator scored in between the two other groups. With regard to ultrasonography of the genital tract, there were no major differences between groups.

“Simulator-based training prepares the students very efficiently for diagnostic procedures on live horses,” explains Christina Nagel, principal investigator of the study. “Simulators are, however, not only an additional teaching tool for our students but also a contribution to animal welfare. Only when students have successfully finished the simulator-based training course are they allowed to perform the same diagnostic procedures in animals.”

The stress perceived by horses during gynaecological examinations had already been studied in 2007 by Christine Aurich and her team. Now she was interested in how students feel when examining a horse compared to examining the teaching simulator. Students with previous training on the simulator were less stressed when finally exposed to a live horse. This conclusion is based on recordings of the students’ heart rate and salivary cortisol concentration during the training sessions and tests. The results were published recently in the scientific journal Reproduction in Domestic Animals.

“The results from these studies encourage us to increase the use of teaching simulators for the training of future veterinarians. Repeated training is the best way to improve the students’ diagnostic skills. Our students gain confidence and clinical routine and are thus well-prepared when confronted with clinical cases in the animal hospital. And well-trained veterinary students are also a contribution to animal welfare,” stated Christine Aurich.  Science Daily  Original web page at Science Daily


* Rooting out doping in racehorses

Doping in the horseracing industry has spurred regulations banning performance-enhancing drugs, as well as calls for an anti-doping agency in the U.S. But as in human sports, testing for certain kinds of prohibited substances has been a challenge. Now scientists report in ACS’ journal Analytical Chemistry a new detection method that could help anti-doping enforcers determine whether a horse has received certain substances.

To give their animals an edge on the track, some horse trainers and veterinarians might administer a single substance, a cocktail of hormones, hormone-mimicking compounds or other drugs. Most are prohibited in the racing world, but catching violators can in some cases be difficult with conventional methods. Existing techniques directly test for the original compounds administered to an animal or their unique metabolites or byproducts. But some of these substances can get processed and eliminated by the animal quickly, making the window for detection very short. George Ho Man Chan, Terence See Ming Wan and colleagues are currently investigating unconventional ways to increase the chances of catching cheaters.

The researchers have identified seven biomarkers in urine that potentially indicate whether a horse has been given aromatase inhibitors, a class of compounds also used by bodybuilders to help regulate hormones and get an edge on the competition. Testing for the changes in these naturally-occurring biomarkers in horse urine could reveal the administration of the substances for about 95 to 195 hours after injection. That’s 2 to 2.5 times longer than conventional screening methods. Being able to find evidence for the administration of these drugs for two or more days longer than before could increase the chances that rule-violators will be caught. With further validation studies, this method could be developed into a useful screening tool for detecting the use of aromatase inhibitors in horses. Science Daily  Original web page at Science Daily


* A horse of a different color: Genetics of camouflage and the dun pattern

Most horses today are treasured for their ability to run, work, or be ridden, but have lost their wild-type camouflage: pale hair with zebra-like dark stripes known as the Dun pattern. Now an international team of scientists has discovered what causes the Dun pattern and why it is lost in most horses. The results, published in Nature Genetics, reveal a new mechanism of skin and hair biology, and provide new insight into horse domestication.

Pale hair colour in Dun horses provides camouflage as it makes a horse in the wild less conspicuous. In contrast, domestic horses, as well as many other domestic animals, have been selected over many generations to be more conspicuous, more appealing or simply different than the wild type. The pale hair colour in Dun horses does not affect all parts of the body; most Dun horses have a dark stripe along their back, and often show zebra-like leg stripes. However, the majority of domestic horses are non-dun and show a more intense pigmentation that is uniformly distributed.

“Dun is clearly one of the most interesting coat colour variants in domestic animals because it does not just change the colour but the colour pattern,” states Leif Andersson, whose group led the genetic analysis. We were really curious to understand the underlying molecular mechanism why Dun pigment dilution did not affect all parts of the body, continues Leif.

“Unlike the hair of most well studied mammals, the dilute coloured hairs from Dun horses are not evenly pigmented the whole way around. They have a section of intense pigmentation along the length of the hair, on the side that faces out from the body of the horse, whilst the rest of the hair has more or less no pigment,” explains Freyja Imsland, the lead author for the genetic analysis, and a PhD student in Andersson’s group. The hairs from the dark areas of Dun horses are in contrast intensely pigmented all around each individual hair. In spite of scientists having studied hair pigmentation in detail for a very long time, this kind of pigmentation is novel to science, and quite unlike that seen in rodents, primates and carnivores.

Genetic analysis and DNA sequencing revealed that Dun versus non-dun colour is determined by a single gene that codes for the T-box 3 (TBX3) transcription factor. In humans, inactivation of the TBX3 gene causes a constellation of birth defects known as Ulnar-Mammary Syndrome. But in horses that have lost their Dun colour, TBX3 mutations do not inactivate TBX3 protein function and instead only affect where the gene is expressed in the growing hair.

“Previous studies in humans and laboratory mice show that TBX3 controls several critical processes in development that affect bones, breast tissue, and cardiac conduction,” explains Greg Barsh, whose group led the tissue analysis. We were surprised to find that TBX3 also plays a critical role in skin and hair development.

The team discovered two forms of dark, non-dun colour, non-dun1 and non-dun2, caused by different mutations.

“Non-dun horses have much more vibrant colour than Dun horses. Non-dun1 horses tend to show primitive markings similar to Dun horses, whereas non-dun2 horses generally don’t show primitive markings. These primitive markings in non-dun1 horses can sometimes lead horse owners to think that their intensely pigmented non-dun1 horses are Dun,” states Freyja Imsland.

To understand how TBX3 affects hair colour, they measured TBX3 distribution in individual hairs relative to other molecules previously known to regulate pigmentation.

“In growing hairs, TBX3 mirrors the distribution of melanocytes, the cells that produce pigment,” explains Kelly McGowan, a senior scientist in the Barsh group. “Our results suggest that TBX3 affects differentiation of specific cells in the hair, creating a microenvironment that inhibits melanocytes from living in the “inner” half of the hair.”

The group speculates that the signals governing where TBX3 is expressed could help to explain zebra stripes. “The region of the body where TBX3 is expressed may account for the stripe pattern,” says McGowan, “whereas the region of the hair where TBX3 is expressed may account for colour intensity.”

The results of the present study indicates that the non-dun2 variant occurred recently most likely after domestication. In contrast, both the Dun and non-dun1 variants predate domestication, which is evident from the observation that ancient DNA from a horse that lived about 43,000 years ago, long before horses were domesticated, carried both Dun and non-dun1 variants.

“This demonstrates that horse domestication involved two different colour morphs (Dun and non-dun1) and future studies of ancient DNA will be able to reveal the geographic distribution and the abundance of the two morphs,” ends Leif Andersson.  Science Daily  Original web page at Science Daily


Adapting to -70 degrees in Siberia: A tale of Yakutian horses

From an evolutionary perspective it happened almost overnight. In less than 800 years Yakutian horses adapted to the extremely cold temperatures found in the environments of eastern Siberia. The adaptive process involved changes in the expression of a plethora of genes, including some also selected in human Siberian groups and the extinct woolly mammoth.

In a new scientific study, the comparison of the complete genomes of nine living and two ancient Yakutian horses from Far-East Siberia with a large genome panel of 27 domesticated horses reveals that the current population of Yakutian horses was founded following the migration of the Yakut people into the region in the 13-15th century AD. Yakutian horses, thus, developed their striking adaptations to the extreme cold climate present in the region in less than 800 years. This is one of the fastest examples of adaptation within mammals. The findings are reported in the PNAS early edition from November 23rd by an international team of researchers led by Dr. Ludovic Orlando from the Centre for GeoGenetics at the Natural History Museum of Denmark, University of Copenhagen.

Horses have been essential to the survival and development of the Yakut people, who migrated into the Far-East Siberia in the 13-15th century AD, probably from Mongolia. There, Yakut people developed an economy almost entirely based on horses. Horses were indeed key for communication and keeping population contact within a territory slightly larger than Argentina, and with 40 % of its surface area situated north of the Arctic Circle. Horse meat and hide have also revealed crucial for surviving extremely cold winters, with temperatures occasionally dropping below -70C.

Horses have been present in Yakutia for a long time as 30,000 year-old Late Pleistocene fossils from the region show. Yet, Dr. Ludovic Orlando and his team now reveal that ancient horses of this region were not the ancestors of the present-day Yakutian horses.

The genome sequence obtained from the remains of a 5,200 year-old horse from Yakutia appears within the diversity of a now-extinct population of wild horses that the team discovered last year in Late Pleistocene fossils from the Taymir peninsula, Central Siberia. This new finding extends by thousands of kilometers eastwards the geographical range of this divergent horse population, which became separated from the lineage leading to modern horses some 150,000 years ago. It also extends its temporal range up to 5,200 years ago, a time when woolly mammoths also became extinct. Dr. Ludovic Orlando says: “This population did not appear on any radar until we sequenced the genomes of some of its members. With 150,000 years of divergence with the lineage leading to modern horses, this makes the roots of this population as deep as the origins of our human species.

Interestingly, the new genome analyses show that the horses that Yakut people now ride and probably rode all along their history (as shown by the genome of a ~200 year-old horse), are not related with this now-extinct horse lineage, but rather with the domesticated horses from Mongolia. Dr. Ludovic Orlando says: “We know now that the extinct population of wild horses survived in Yakutia until 5,200 years ago. Thus it extended from the Taymir peninsula to Yakutia, and probably all across the entire Holarctic region. In Yakutia, it may have become extinct prior to the arrival of Yakut people and their horses. Judging from the genome data, modern Yakutian horses are no closer to the extinct population than is any other domesticated horse.”

The new genome analyses show that the founders of the modern Yakutian horse population probably entered into the region with Yakut horse-riders in the 13-15th Century AD. Dr. Ludovic Orlando further adds: “This is truly amazing as it implies that all traits now seen in Yakutian horses are the product of very fast adaptive processes, taking place in about 800 years. This represents about a hundred generations for horses. That shows how fast evolution can go when selective pressures for survival are as strong as in the extreme environment of Yakutia.

The team leveraged on their large horse genome panel to identify the genes underlying such adaptations. Strikingly, they found that a large fraction of the selection signatures were not located within the coding region of genes, but within their upstream regulatory regions. It, thus, suggests that the adaptation of Yakutian horses to their environment took place through a massive reprogramming of gene expression. Dr. Pablo Librado comments: “The founder group of the current population was quite reduced in size. The genetic variation standing within gene bodies was, thus, probably limited in comparison to that present within regulatory regions. These regulatory variants probably offered as many possibilities to rapidly modify horse traits in a way that was compatible with their survival.”

Focusing on the genes and their regulatory regions showing evidence of selection, the team identified key biological functions involved in the adaptive process. These concern morphological changes, hormonal responses involved in the regulation of thermogenic requirement and the production of anti-freezing compounds. The list of selective signatures also include genes, such as TGM3, which is involved in hair development and might be responsible for the extremely hairy winter coat of Yakutian horses. Dr. Librado adds: “In addition to unveil their evolutionary origins, our approach helped narrow down the genetic basis of adaptations that are unique to Yakutian horses. In one word, their genetic makeup. We also found genes that were reported to have undergone selection in other Arctic populations, such as indigenous Siberian humans, and even the woolly mammoth. It provides a compelling example of evolutionary convergence, where unrelated groups exposed to similar environments end up independently developing similar adaptations.”

Such genes showing convergent signals of adaptation include in humans PRKG1, which is involved in the shivering response to cold, and BARX2 in the woolly mammoth which is involved in hair development.

Dr. Clio Der Sarkissian concludes: “Our work shows the power of ancient DNA, as we would have never been able to discover the existence of the now extinct ancient population of horses by analyzing the genome of modern horses. With ancient genomes, we can now understand the dynamics of past populations at unprecedented levels and track, through space and time, how these became adapted to changing environments. Applied to pre-industrial museum specimens, our approach can therefore help following how extant populations have been affected by ongoing climate changes and recent human activities. This can help develop tailor-made conservation programs, which will be ultimately essential for preserving endangered populations.” The group has already implemented such approaches for preserving the Przewalski’s horse, which represents the last truly wild horse living in the planet.  Science Daily  Original web page at Science Daily


Test tube foals that could help ensure rare breed survival

The recent birth of two test tube foals in the UK, as part of a collaborative project conducted by leading fertility experts, could help benefit rare breed conservation and horses with fertility problems. The births mark the successful completion of a three-year program, the aim of which was to establish and offer advanced breeding methods that are not routinely available in the UK. The births mark the successful completion of a three-year program, led by the University of Liverpool, the University of Surrey and Twemlows Stud Farm. The aim of the project was to establish and offer advanced breeding methods that are not routinely available in the UK.

It is thought that these processes could have further use in breeds under threat of extinction and for valued horses that have died or in cases where mares or stallions have specific fertility problems.

One method, called intracytoplasmic sperm injection (ICSI), has the potential to allow greater numbers of offspring to be produced from individual mares and from stallions where sperm samples are limited, allowing breeds to continue in larger numbers. Importantly, this method could allow the embryos of rare breeds to be ‘frozen’, creating a safety net of ‘reserve animals’ should anything threaten the existing stock.

Niamh Lewis, a veterinarian researcher at the University of Liverpool, who managed the project said: “These are complex methods which are currently offered by only a very few centres worldwide. The ability to perform these techniques reliably offers new hope to help overcome various fertility issues in stallions and also provides opportunities to create offspring from valuable mares who have died unexpectedly or cannot conceive in their own right.”

The foals were born using two different advanced breeding techniques. In June this year a foal named Twemlows Simba became the first foal in the UK to be born using Oocyte Transfer, a technique that involves oocytes (eggs) being collected from a donor mare and then transplanted into a surrogate female before being fertilised.

A second foal called Twemlows Little ICSI was born earlier this month using an ICSI. This technique is already used with great success for infertile human couples and involves a single sperm being injected into an egg through a thin glass pipette to create an embryo which is then transferred to a surrogate female. In this case the egg had been harvested from the ovary of a mare that died 11 months ago and was then matured in the laboratory ahead of the procedure. If rare breed embryos can be reliably frozen, as opposed to just semen as currently archived then, in case of a crisis, the breed could be resurrected by returning the embryos to surrogate mares.

Professor Caroline Argo from the University of Surrey, who was the academic lead for the project adds: “At the moment, we can freeze stallion sperm reliably but not horse eggs or embryos. However, ICSI embryos are smaller and more robust to the freezing process. Now that this method has proved successful, it could be possible to use it more routinely and widely for the purposes of conservation.”

The project was a Knowledge Transfer Partnership, jointly funded by the government’s Technology Strategy Board and Twemlows Stud Farm, Shropshire, and encompassed a major collaborative effort, which included working with consultant clinical embryologists in human medicine.

Mr Edward Matson of Twemlows Stud Farm said: “We have always strived to stay at the forefront of horse breeding and to offer our clients the most up to date techniques which are firmly centred on good science and focus on the welfare of their animals.

“The opportunity to collaborate with academic and clinical partners has allowed us to extend our service to include these advanced techniques. Until now, clients wishing to embark on these methods were largely dependent on shipping animals to overseas clinics.

Tom Beeston, CEO of the Rare Breeds Survival Trust, said: “Breeding numbers of all our native equine breeds continue to decline, if not halted soon our gene bank may be needed to reconstitute a breed, it really is that serious. Being able to freeze embryos as well as semen will mean we can do this completely and faster. This project is by far our best hope of being able to do this soon.”  Science Daily  Original web page at Science Daily


* Mare pedigree influences offspring more than previously thought.

In horse breeding, stallions are usually used to establish a breeding line. In some cases, however, the maternal lineage plays a more important role. Researchers from the Vetmeduni Vienna looked at the gestation length of different mare families and discovered that the length of gestation varies significantly from lineage to lineage. Certain families also produce more female offspring than male foals. The results were published in the journal PLOS One.

Owners of sport and leisure horses are keen on knowing the parentage of their animals. A horse with a good pedigree will often have the desired characteristics in terms of speed, physique and health.

At the Graf Lehndorff Institute for Equine Science, a joint research institution of the Vetmeduni Vienna and the Brandenburg State Stud in Germany, Juliane Kuhl and Christine Aurich investigated the degree to which the maternal lineage influences gestation length and foal characteristics. Together with statistician Kathrin Stock of the agricultural statistics centre VIT in Germany, they analysed the data records for 640 pregnancies in 142 mares.

The broodmares could be assigned to different mare families or lineages. The analysis revealed that the average length of gestation, which in horses ranges between 320 and 360 days, varies from family to family. The gestation length of some maternal lineages was on average 10 days longer than in other families. The fact that gestation length for male foals tends to be generally longer than for female foals is added to the variation from family to family.

“We can still not predict the exact time of birth. The individual fluctuations among individual pregnancies are simply too large. But the information gained from the study can help us to narrow the possible range,” says first author Juliane Kuhl.

“The length of gestation is also of interest for horse breeders. Ideally, a broodmare should give birth to a foal every year. Due to the average gestation which covers approximately 11 months, longer gestation lengths result in a delay in birth of the next foal. Breeders are interested in having foals born at the beginning of the year, as the horses will then compete better against animals born in the same year,” Kuhl explains.

The study also showed that certain maternal lineages produce more female than male foals. The age of the mare also plays a role. Young mares who have their first pregnancy when they are three years old will produce more female foals. Older mares also tend to have more female offspring. For middle-aged mares between four and twelve years the foal sex ratio is balanced.

“These results are important for horse breeders. They could possibly choose their mares depending on the desired sex of a foal,” Kuhl believes.The mechanism behind this phenomenon remains unclear, however.

“We suspect that these effects are due to the differences in mitochondrial DNA. This specific DNA is inherited over the maternal line and influences cell metabolism and placenta function,” says study director Christine Aurich.

“We also know that female embryos are more resilient. As 20 to 30 percent of early pregnancies are lost spontaneously, it is possible that male embryos survive less frequently. This could be a reason for the observed shift in the sex ratio. But it is also possible that embryo survival is influenced by differences in placental function,” Aurich says.   Science Daily  Original web page at Science Daily


After 100 years in captivity, a look at the world’s last truly wild horses

In the 1870s, the world’s last truly wild horses, known as Przewalski’s horses, lived in the Asian steppes of Mongolia and China. But by the 1960s, those wild horses were no longer free. Only one captive population remained, descended from about a dozen wild-caught individuals and perhaps four domesticated horses. Thanks to major conservation efforts, the current population of Przewalski’s horses numbers over 2,000 individuals, with about a quarter living in reintroduction reserves.

Now, researchers reporting in the Cell Press journal Current Biology on September 24 have sequenced the complete genomes of eleven Przewalski’s horses, including all of the founding lineages and five historical, museum specimens dating back more than a century, and compared them to the genomes of 28 domesticated horses to provide a detailed look at the endangered animals, both past and present.

“The novelty of our approach is to have not only surveyed the present-day genomic diversity of Przewalski’s horses, but also to monitor their past genomic diversity, leveraging on museum specimens,” says Ludovic Orlando of the University of Copenhagen’s Natural History Museum of Denmark. “That way we could assess the genetic impact of more than 100 years of captivity in what used to be a critically endangered animal.”

The genomic evidence helps to solve a long-standing debate in horse evolution, regarding the relationships between wild and domestic horses. The ancestors of Przewalski’s horses and domesticated horses remained connected by gene flow for a long time after their divergence, some 45,000 years ago, the researchers report. Their populations continued to mix even after humans started to domesticate the horse about 5,500 years ago.

“As a matter of fact, we also show that very early in captivity–in the early 1900s–domestic horses contributed significantly to some lineages of the Przewalski’s horse pedigree,” Orlando says. “It implies that not all of the surviving Przewalski’s lineages represent the gene pool of wild horses equally.”

Orlando and his colleagues found the greatest genetic differences between domesticated and wild horses in genes involved in metabolism, cardiac disorders, muscle contraction, reproduction, behavior, and signaling pathways.

The findings also show that the last 110 years of captivity have left a mark on the Przewalski’s horses, in the form of lower genetic diversity, increased inbreeding, and, in some cases, the significant introduction of genes from domesticated individuals. In the most extreme cases, about a quarter of the genomes of Przewalski’s horses consisted of gene variants inherited from domesticated horses.

But there is some good news: “Even though Przewalski’s horses went through an extreme demographic collapse, the population seems to recover, and is still genetically diverse,” Orlando says. “There is, thus, hope for [other] endangered populations, fighting similar demographic issues.”

The findings also serve as evidence of the importance of ancient DNA evidence in understanding domestication. The researchers say they plan to screen many more ancient horses–both wild and domestic–over time, with the goal of reconstructing the history of horses’ 5,500 years of domestication.  Science Daily  Original web page at Science


Racehorses at risk from misuse of cobalt, new study finds

In a new study published in The Veterinary Journal, scientists from the University of Surrey warn about the numerous risks posed to racehorses from the misuse of cobalt chloride, a banned performance-enhancing agent that has been used illegally by trainers in Australia and USA. The team of researchers have uncovered that when excessive levels of the alleged performance-enhancing substance are administered to a horse, it can cause serious cardiovascular issues, potential nerve problems, thickening of the blood and thyroid toxicity. The researchers also pointed to the lack of evidence for enhanced performance in horses and human athletes.

Cobalt, required by all horses in order to survive, is normally present at very low levels through various feedstuffs. However, excessive amounts of impure formulations of the substance, which can be administered easily as a powder, feed supplement or injection, can lead to severe side effects, such as long-term damage to vital organs such as the heart. Indeed in humans, cobalt salts have been used in the past to treat rare forms of anemia. However, it has been associated with a variety of adverse effects, including gastrointestinal neurologic, cardiovascular, and thyroid problems, and as a result, its use has been discontinued.

Not a prescription medication, various cobalt salts are available from a variety of commercial sources. The salts are impure and are inexpensive, easily accessible and not subject to medicines regulation. “We have grave concerns over a potentially lethal practice in the race horsing industry, and are most concerned that some trainers continue to use Google as their source of information,” said lead author Professor Ali Mobasheri from the University of Surrey.

“It is the duty of veterinary surgeons working in the industry to ensure that horse trainers are aware of the dangers of its ‘amateur’ use. “Currently there is no evidence to suggest that cobalt chloride can enhance human or equine athletic performance. It is our hope that this study will increase greater awareness and prompt a broader discussion about the misuse of this substance.”  Science Daily  Original web page at Science Daily


* Birth of four foals from genotyped, cryopreserved embryos: A first in Europe

Four foals were successfully born as the result of the transfer of genotyped and cryopreserved embryos. Researchers report that this is a first in Eurpoe. The goal of this work is to better understand embryonic development, control livestock reproduction, and maintain breed genetic diversity. Furthermore, it is advantageous for the horse industry to be able to determine the traits of a future foal. Genotyping allows scientists to choose the embryos they want to use based on different criteria: sex, like in this experiment, the absence of known genetic disorders, or, perhaps in the future, other traits that are tied to behavior, such as emotivity or sociability.

IFCE and INRA announced that, for the first time ever in Europe, four foals were successfully born as the result of the transfer of genotyped and cryopreserved embryos. The goal of this work is to better understand embryonic development, control livestock reproduction, and maintain breed genetic diversity. Furthermore, it is advantageous for the horse industry to be able to determine the traits of a future foal. The INRA Val de Loire center at Nouzilly is where the technology to maintain embryo viability following genotyping and cryopreservation was honed, and then, last summer, the transfer of several embryos took place at the IFCE Haras du Pin Stud Farm, located in the French department of Orne. The partnership between the two institutions has now been cemented by the birth of the healthy foals.

Seven days after fertilization, embryos were collected from Welsh B ponies that are part of INRA’s livestock. The embryos were genotyped: scientists sampled some of the embryos’ cells to analyze their genomes. In this experiment, embryos were selected based on sex, the idea being to use sex-based selection to test the technique’s feasibility. The embryos were then cryopreserved in liquid nitrogen (at -196°). Last summer, they were transferred into saddlebred mares at the Haras du Pin center. After an 11-month gestation period, the foals were born in May. They were of the expected sex: two females and two males. This is the first time that such an event has taken place in Europe, and it is the product of more than 10 years of various types of embryonic research carried out by INRA and IFCE scientists.

Although embryo preservation techniques are already well developed for bovines, small ruminant species, and even humans, preserving horse embryos is a very complex process. For instance, horse embryos vary greatly in size: 7-day-old embryos range in diameter from 200 to 700 micrometers. It is very difficult to cryopreserve the largest embryos because the liquid inside them forms ice crystals when the embryos are frozen at very cold temperatures. What’s more, horse embryos are surrounded by a capsule that interferes with successful cryopreservation. There are several reasons why being able to successfully cryopreserve embryos is important. For example, it allows us to maintain breed genetic diversity, particularly that of breeds with small population sizes, such as the Landais or the Poitevin Mulassier. Furthermore, the factor that currently limits the use of embryo transfer is its cost: the transfer center has to maintain a team of recipient mares that are reproductively synchronized with the donor mares. Cryopreservation means that the transfer doesn’t have to take place immediately; it can wait until a recipient mare becomes available to receive the embryo. Finally, it may now be possible to directly repopulate horse herds that have experienced losses as a result of various issues, such as disease-related problems, instead of having to use the indirect technique of crossbreeding.

Genotyping allows us to choose the embryos we want to use based on different criteria: sex, like in this experiment, the absence of known genetic disorders, or, perhaps in the future, other traits that are tied to behavior, such as emotivity or sociability. It is advantageous for the horse industry to be able to determine the traits of a future foal. We will next aim to simplify the process — to make this technology more accessible and user friendly for those in the horse industry.  Science Daily

Original web page at Science Daily


* Researchers unearth county colic risk in horses

A particular gastrointestinal disorder, which causes colic, or abdominal pain, in horses, is more prevalent in Lancashire compared with other nearby counties, according to researchers at Lancaster University and the University of Liverpool.

They have also found that Idiopathic Focal Eosinophilic Enteritis (IFEE), lesions causing an obstruction in a horse’s small intestine, is actually seasonal and occurs more often in younger horses. The findings emerged from a collaborative study between Lancaster University statisticians Dr Deborah Costain and Dr Chris Sherlock and equine specialist Professor Debra Archer from the University of Liverpool and have recently been published in the journal Plos ONE.

The study used data from horses and ponies admitted over a ten-year period to The University of Liverpool’s Philip Leverhulme Equine Hospital for exploratory examinations to investigate the cause of colic. Of these, 85 were IFEE cases and, for the study, a further 848 subjects were selected at random from those without IFEE. The cause of IFEE is currently unknown and the aim of the study was to examine the effects of age, time of year and geographical location on the risk of the condition. The data analysis used advanced techniques in spatial statistics, a particular specialism of Lancaster University. Dr Sherlock said: “Our analysis strongly suggests that horses located in a certain region appear to be at increased risk of IFEE.”

The study, which covered a region from Leicestershire to Cumbria, showed there was an increased risk of this particular gastrointestinal disorder in horses from around Lancashire. It added that as factors, such as breed, management practices and feed types, were unlikely to vary according to the observed spatial distribution, it was plausible that environmental factors might play a role in the development of IFEE. The report suggested that future research should, therefore, consider investigation of environmental factors such as soil types and pathogens associated with similar spatial patterns of disease in other species, including humans. A seasonal pattern was evident with the greatest risk of IFEE being identified between July and November.

The risk of IFEE was found to decrease with increasing age, with younger horses, from birth to five-years-old, being at greatest risk. “This work enables us to better identify horses at risk of IFEE and has provided some clues about the possible cause of the condition which requires further research,” said Professor Archer. “Horse owners in the Lancashire area should be aware that the chances of their horse or pony developing this condition overall are still relatively low but we would appear to see more cases of IFEE here than anywhere else in the study region. It is important that we continue to try to find out what the underlying cause is to determine whether it can be prevented from occurring.” Colic is one of the most common causes of death in horses and ponies and has important economic costs and welfare implications for the equine industry and horse/pony owners. Science Daily Original web page at Science Daily


* Ancient horse DNA revealed human breeding preferences: Leopard complex spotting and congenital night blindness

White coat with black spots: almost every child knows “Lilla Gubben” the horse of Pippi Longstocking. But what about the popularity of spotted and speckled horses (so called leopard complex spotting) during the last millennia? Researchers found out that the occurrence of these horses fluctuated considerably in the course of history. Under the leadership of scientists of the German Leibniz Institute for Zoo and Wildlife Research (IZW) an international team of researchers genetically analysed the phenotype (appearance) of 96 archaeological bones and teeth of horses originating from the late Pleistocene to the Medieval Times. Although a considerable number of domestic horses from the early Bronze Age (2700 — 2000 B.C.) have been genetically identified with leopard spotting complex, this coat colour seems to have almost disappeared at the end of this period. One reason might be that homozygous animals (e.g. Appaloosa and American Miniature Horse) are night-blind in addition to the white coat colour. The ability to see is of great importance for communication, orientation, search for food and avoiding predators. Therefore night-blind animals have a barely chance to survive in the wild. In human care night-blind horses are described as nervous and timid, which are difficult to handle at dusk and darkness. About 1000 to 1500 years later the leopard complex again occurs increasingly. The coat colour was reintroduced into the domestic gene pool from numerous wild animals existing in those days. Different preferences of the horse breeders in the course of the millennia emphasise the importance of genetic diversity of domestic animals. In times where the original wild form of horse and cattle are long extinct and backcrossing hence is impossible, the modern animal breeding still target on a loss of genetic diversity. The decline in variability enormously restricts future changes in breeding aims and makes us dependent on only a few high-performance breeds. After the Iron Age a renewed upswing on leopard complex spotted horses was reported. “The behaviour of breeders and their preferences changed at that time as it does today” says Arne Ludwig from the IZW, head of the study. The changing interests in leopard complex spotted horses can also be recognised in Medieval Times, where they enjoyed a high reputation as paintings and text samples demonstrate. They belonged to the favourite animals of the nobles and were symbol of chastity. Also in Baroque period they were favoured, before they go out of date. Today spotted coat patterns occur in many breeds and breeders show an increasing interest in recent years. “If the theory of the alternative selection applies then it can explain how genetic diversity in domestic populations could be preserved in spite of relevant selection for or against a certain characteristic. The problem in breeding nowadays is that we cannot go back to the appropriate wildlife species, because they are simply eradicated or the wild types vanished by selection. This has to be evaluated negatively for the gene pool of the today’s domestic animal breeds. The missing genetic diversity highly restricts the possibilities of breeding in the future,” comments Ludwig.  Science Daily  Original web page at Science Daily


Test for horse meat developed

Scientists at the Institute of Food Research on the Norwich Research Park have teamed up with Oxford Instruments to develop a fast, cheap alternative to DNA testing as a means of distinguishing horse meat from beef. Because horses and cattle have different digestive systems, the fat components of the two meats have different fatty acid compositions, as the team report in the journal ‘Food Chemistry’. The new method looks at differences in the chemical composition of the fat in the meats, using similar technology to a hospital MRI scanner. In just ten minutes, a technician can determine whether a piece of raw meat is horse or beef. The method, developed with funding from Innovate UK and the Biotechnology and Biological Sciences Research Council (BBSRC) has recently been trialled in an industrial setting by a leading meat processor. It is currently being extended by the team of scientists to test for other meat species, including pork and lamb. The horse meat scandal of 2013 was sparked by the discovery of horse meat in a number of beef burgers. Soon, horse meat was detected in other meat products, leading to millions of pounds worth of food being taken off supermarket shelves. The crisis exposed the potential vulnerability of the meat supply chain to fraud and even to threats to public health, and highlighted gaps in testing. The currently favoured method of meat species testing relies on DNA, which can tell one meat from another based on the genetic makeup of the source animals, but is relatively slow and expensive and prone to contamination if not used carefully. In response to this, a new method using a totally different approach was developed by Oxford Instruments and IFR. The key technology is the ‘Pulsar’, a high resolution bench-top NMR spectrometer developed by Oxford Instruments. NMR spectroscopy is a well-respected analytical technique used in chemistry labs worldwide. However, conventional instruments are large and expensive, and rely on super-cooled magnets and highly trained personnel to run them. Pulsar in contrast is based on permanent magnets and ease of operation. For a test to be useful as a screening tool it needs to be quick and cheap. With this goal in mind, the team discovered that a couple of minutes shaking about a gram of meat in a solvent followed by a few minutes of data acquisition on Pulsar was enough to tell horse meat from beef. Software to carry out mathematical analysis of the spectral data has also been developed at IFR. “It’s a stroke of luck really that some of the most important meats turn out to have fat signatures that we can tell apart so easily with this method,” says Dr Kate Kemsley. “It’s been very satisfying to see results from a real industrial setting sit right on top of those we generated in our two labs. We think this testing method should work well at key points in the supply chain, say at meat wholesalers and processors.” Science Daily Original web page at Science Daily


Do women and men ride differently? Horses cannot tell the difference

Scientists at the Vetmeduni in Vienna have analysed how horses are affected by the sex of their riders. Various parameters of stress were determined in horses and their riders when they covered an obstacle course. The results were surprising: the level of stress on a horse is independent of whether a man or a woman is in the saddle. Furthermore, the stress responses of male and female riders are essentially the same. The results have been published in the Journal of Comparative Exercise Physiology. For centuries, horse riding was largely restricted to males. The previous situation is in stark contrast to the present day, when nearly 80 percent of riders are women. Modern-day equestrian sports are unique in that men and women compete directly against one another at all levels, from beginners in gymkhanas to national champions in the Olympic Games. “For this reason it is interesting to consider whether a theory of riding that was developed exclusively for men can be applied to women,” explains Natascha Ille, the first author of the recent publication. As Ille notes, “It is often assumed that women are more sensitive towards their horses than men. If this is so, male and female riders should elicit different types of response from their horses.” Ille, Christine Aurich and colleagues from the Vetmeduni Vienna´s Graf Lehndorff Institute tested this notion by examining eight horses and sixteen riders, including eight men and eight women. Each horse had to jump a standard course of obstacles twice, ridden once by a male and once by a female of similar equestrian experience. The scientists monitored the levels of stress in the horses and their riders, checking the amounts of cortisol in the saliva and the heart rates. The results were unexpected. The level of cortisol in horses’ saliva increased during the test but the increase was not affected by the sex of the rider. The horses’ heart rates also increased as a result of taking the course but the increase was irrespective of the human partner in the saddle. The tests on the riders gave similar conclusions. Again, the level of cortisol in the saliva increased but there was no difference between men and women. The riders’ pulses sped up when the horses switched from a walk to a canter and accelerated further during the jumping course. But the heart rate curves for male and female riders were close to identical.

In a second experiment, Ille and her colleagues studied the pressure exerted on a horse’s back via the saddle. As she explains, “Depending on the rider’s posture and position, the pattern of pressure on the horse’s back may change dramatically.” A special pad placed directly under the saddle was used to analyse saddle pressure in walk, trot and canter. Because female riders are generally lighter than males, the saddle pressure was lower when horses were ridden by females. However, the distribution of pressure did not differ and there was no evidence of differences in the riding posture between males and females. So what does all this mean for modern equestrian sports? Aurich is keen to reassure potential competitors that horses are truly gender-neutral. As she puts it, “Assuming that there is no difference in riding ability, from the horse’s point of view, it does not seem to matter whether the human partner is male or female. Our results make it extremely unlikely that horses have a preference for riders of one sex over the other. And when male and female riders compete against one another in equestrian sports, all of them have similar chances of doing well.”  Science Daily  Original web page at Science Daily


Horses communicate with eyes and mobile ears

Horses are sensitive to the facial expressions and attention of other horses, including the direction of the eyes and ears. The findings, reported in the Cell Press journal Current Biology on August 4, are a reminder for us humans to look beyond our own limitations and recognize that other species may communicate in ways that we can’t, the researchers say. After all, human ears aren’t mobile. “Our study is the first to examine a potential cue to attention that humans do not have: the ears,” says Jennifer Wathan of the University of Sussex. “Previous work investigating communication of attention in animals has focused on cues that humans use: body orientation, head orientation, and eye gaze; no one else had gone beyond that. However, we found that in horses their ear position was also a crucial visual signal that other horses respond to. In fact, horses need to see the detailed facial features of both eyes and ears before they use another horse’s head direction to guide them.” The new study also challenges the earlier held notion that animals with eyes to the sides of their heads cannot glean information based on the direction of one another’s gaze. Wathan and the study’s senior author Karen McComb took photographs to document cues given by horses when they were paying attention to something. Then Wathan and McComb used those photographs as life-sized models for other horses to look at as they chose between two feeding buckets. In each case, the horse in the photo was paying attention to one of the buckets and not the other. In some instances, the researchers also manipulated the image to remove information from key facial areas, including the eyes and the ears. The researchers’ observations show that horses rely on the head orientation of their peers to locate food. However, that ability to read each other’s interest level is disrupted when parts of the face — the eyes and ears — are covered up with masks. The ability to correctly judge attention also varied depending on the identity of the horse pictured, suggesting that individual facial features may be important, the researchers report. Wathan and McComb plan to continue to explore facial features related to the expression of emotion in their horses, noting that horses’ rich social lives and close relationship to humans make them particularly interesting as study subjects. Our understanding of horses’ social lives might also have implications for their welfare. “Horses display some of the same complex and fluid social organization that we have as humans and that we also see in chimpanzees, elephants, and dolphins,” Wathan says. “The challenges that living in these societies create, such as maintaining valuable social relationships on the basis of unpredictable interactions, are thought to have promoted the evolution of advanced social and communicative skills. There is a general interest in studying species with this social structure.”  Science Daily  Original web page at Science Daily


Hendra virus vaccine, a One Health approach to protecting horse, human, and environmental health

In recent years, the emergence of several highly pathogenic zoonotic diseases in humans has led to a renewed emphasis on the interconnectedness of human, animal, and environmental health, otherwise known as One Health. For example, Hendra virus (HeV), a zoonotic paramyxovirus, was discovered in 1994, and since then, infections have occurred in 7 humans, each of whom had a strong epidemiologic link to similarly affected horses. As a consequence of these outbreaks, eradication of bat populations was discussed, despite their crucial environmental roles in pollination and reduction of the insect population. We describe the development and evaluation of a vaccine for horses with the potential for breaking the chain of HeV transmission from bats to horses to humans, thereby protecting horse, human, and environmental health. The HeV vaccine for horses is a key example of a One Health approach to the control of human disease. Hendra virus (HeV) is an emerging zoonotic paramyxovirus for which natural reservoirs are the 4 species of flying fox (Pteropus bats) found on mainland Australia. HeV was discovered in 1994, and since then, infections have occurred in 7 humans, 4 of whom died. Each case-patient had a strong epidemiologic connection to similarly affected horses through exposure to equine secretions late in the incubation period, during terminal illness, or at the time of postmortem examination of infected animals: no human case of HeV infection has been attributable to direct spillover from bats.

HeV infection in the bat host appears to be asymptomatic; however, in humans and horses there is evidence of initial virus replication in the nasopharynx that progresses through a viremic phase during which the virus spreads to major organ systems, resulting in disseminated endothelial cell infection, vasculitis, encephalitis, and pneumonia. There is no licensed anti-HeV therapeutic drug for use in any species. Experimental exposure of horses to HeV/Australia/Horse/2008/Redlands under Biosafety Level 4 (BSL-4) conditions identified comparatively low gene copy numbers in nasal secretions early in the incubation period. However, gene copy numbers increased exponentially with the onset of fever, when viral genome could also be recovered from blood, oral secretions, urine, and feces. Rapid progression of clinical signs, as observed in equine field cases of this disease, led to euthanasia of experimental animals on humane grounds. Viral RNA was recovered from all tissues sampled at postmortem examination, and virus was reisolated from lung, brain, lymphoid tissues, and kidney . In accordance with epidemiologic observations, it was concluded that HeV-infected horses in the immediate presymptomatic or symptomatic stages of disease pose a high risk for transmission of HeV to humans. This risk is then exacerbated because it is symptomatic horses that come to the attention of veterinarians, leading to various clinical investigations (e.g., respiratory tract endoscopy) that may facilitate human exposure to virus.

During 1994–2010, there were a total of 14 HeV outbreaks, including those with the 7 human infections. Then, in 2011, for reasons that are as yet poorly understood, an unprecedented 18 equine incidents, some involving >1 horse, occurred within a 3-month period and over an expanded geographic range, emphasizing that HeV was an unmanaged emerging disease. These events were accompanied by a marked rise in the number of HeV-related media reports. The reports had an increasingly politicized focus on the role (and control) of flying foxes as carriers of HeV  and a deemphasis of the critical role played by horses in HeV transmission to humans. Heightened public awareness of the risk that infected horses posed to humans persisted and was paralleled by increased numbers of veterinarians leaving equine practice because of personal safety and liability concerns . The considerable investment in education and improved infection control measures that had been implemented did not effectively mitigate perceptions around the risks associated with the routine veterinary care of horses. The actual mechanism of HeV transmission from bats to horses is probably complex and dependent upon socioeconomic, environmental, and ecologic factors, and there is currently no straightforward solution for preventing transmission. Eradication of flying foxes would pose extraordinary operational challenges, notwithstanding attendant moral, ethical, and environmental issues, and eliminating the interface between bats and horses is impractical for periurban and rural communities. The most direct approach for reducing the risk posed to humans by HeV-infected horses would be implementation of a strategy that will lead to suppression of virus replication in horses. We describe the development and evaluation of a vaccine for horses with the potential for breaking the chain of HeV transmission from bats to horses to humans, thereby protecting horse and human health. The emergence of several highly pathogenic zoonotic diseases in humans in recent years has led to a renewed emphasis on the interconnectedness of human, animal, and environmental health, otherwise known as One Health.  Emerging Infectious Diseases March 4, 2014 Original web page at Emerging Infectious Diseases


New, unusually large virus kills anthrax agent

From a zebra carcass on the plains of Namibia in Southern Africa, an international team of researchers has discovered a new, unusually large virus (or bacteriophage) that infects the bacterium that causes anthrax. The novel bacteriophage could eventually open up new ways to detect, treat or decontaminate the anthrax bacillus and its relatives that cause food poisoning. The work is published Jan. 27 in the journal PLOS One. The virus was isolated from samples collected from carcasses of zebras that died of anthrax in Etosha National Park, Namibia. The anthrax bacterium, Bacillus anthracis, forms spores that survive in soil for long periods. Zebras are infected when they pick up the spores while grazing; the bacteria multiply and when the animal dies, they form spores that return to the soil as the carcass decomposes. While anthrax is caused by a bacterium that invades and kills its animal host, bacteriophages, literally “bacteria eaters” are viruses that invade and kill bacterial hosts. The first thing the team noticed was that the virus was a voracious predator of the anthrax bacterium, said Holly Ganz, a research scientist at the UC Davis Genome Center and first author on the paper. They also noticed that the new virus, named Bacillus phage Tsamsa, is unusually large, with a giant head, a long tail and a large genome, placing it among the largest known bacteriophages.

Tsamsa infects not only B. anthracis but also some closely related bacteria, including strains of Bacillus cereus, which can cause food poisoning. Sequencing the genome allowed researchers to identify the gene for lysin, an enzyme that the virus uses to kill bacterial cells, that has potential use as an antibiotic or disinfecting agent. Bacteriophages are often highly specific to a particular strain of bacteria, and when they were first discovered in the early 20th century there was strong interest in them as antimicrobial agents. But the discovery of penicillin and other antibiotics eclipsed phage treatments in the West, although research continued in the Soviet Union. “With growing concerns about antibiotic resistance and superbugs, people are coming back to look at phages,” said Ganz said. One advantage of bacteriophages is that because they tend to be very specific, they can potentially target only “bad” bacteria while leaving beneficial bacteria unharmed. Also, phages evolve with the host and have the potential to overcome bacterial resistance, said coauthor Jochen Klumpp of the Institute of Food, Nutrition and Health, ETH Zurich. Ganz began the work as a postdoctoral scientist on a team led by Wayne Getz, Professor of Environmental Science, Policy and Management at UC Berkeley and at the University of KwaZulu-Natal, South Africa. Sequencing of the phage genome was conducted at UC Davis after Ganz joined the laboratory of Professor Jonathan Eisen. Ganz said that she hoped the publication of the phage’s sequence information would enable other researchers to investigate further and potentially develop applications for the phage and its proteins. “You might use it to detect the anthrax bacillus or B. cereus; use it as an alternative to antibiotics or as part of a decontaminant,” she said. Science Daily
February 18, 2014 Original web page at Science Daily


How horses can teach humans communication skills, kindness

A nudge from the nose of a free-roaming zebra, or towering, 2,500-pound Clydesdale draft horse, might send others running. But Lauren Burke, a graduate student at Case Western Reserve University’s social work school, instead extends a curved hand to return the equine “hello.” In her required social work field placement, Burke spent the last 18 months at Spirit of Leadership at the Pebble Ledge Ranch in Novelty, Ohio, learning to communicate with horses (and a zebra), becoming “one with the herd” and teaching others how to do the same in an experiential learning with horses program that inspires self-discovery. By developing a sensitivity to the body language of horses, explained Jacalyn Lowe Stevenson, Spirit of Leadership founder and president and Burke’s supervisor, humans may better understand nonverbal communication in each other — the goal of which is to enhance the group dynamic, from the corporate boardroom to the family dining room table. Among corporate and nonprofit clients are ArcelorMittal, Lubrizol, Humana, University Hospitals of Cleveland, Cleveland Metroparks Zoo, Ohio Mutual Insurance, the Cleveland Rape Crisis Center, the American Heart Association, Bratenahl Police, Israeli Defense Force, and U.S. military veterans. Understanding a horse’s non-verbal body language and, in turn, being accepted as a member of the herd is part of a new approach Stevenson pioneered and developed, called Equine Guided Coaching and Experiential Learning with Horses.

Stevenson’s work and organization has inspired Burke, who wants to use animal therapy and personal discovery (particularly horses) in her social work profession. Stevenson, MSSA, an adjunct instructor at the Jack, Joseph and Morton Mandel School of Applied Social Sciences and the Weatherhead School of Management, uses horses as the center of therapy that promotes self-discovery, innovation and positive relationships. At Spirit of Leadership, Burke learned how to advance the program’s vision as a catalyst for leadership excellence, team performance and organizational spirit — all inspired by horses. Burke has worked directly with clients, has helped plan an international conference on equine-guided coaching, traveled to Atlanta, Baltimore and Lexington, Ky., to establish herd relationships and work with corporate clients in each city. Of course, she’s also had to experience the more mundane, cleaning barns and feeding horses. Before clients are introduced to the horses, Burke begins with a 15-minute lesson in nonverbal horse communications — the meaning of ear positioning, swishing tails, and handling a nose-to-nose welcome. No one rides the horses; it is about engaging in a relationship with the horses and team members. Burke teaches clients how to go from greeting the horses, to creating respect and trust to leading a horse through an obstacle course, called the “Field of Possibilities.” By doing so, clients achieve skills in working as a team.

This unique experiential learning evolved from Stevenson’s counseling sessions on her 80-acre ranch. She noticed clients always stopped to talk to horses freely roaming the pastures and woods on her Western Reserve Land Conservancy Trust property along the Chagrin River. The attraction to the horses inspired Stevenson to put chairs in the field and conduct client sessions among the grazing horses. Clients began to notice how the horses responded to their attitudes. The horses would approach if they sensed people were excited to see them and passionate about what they were discussing or retreated if they sensed disinterest. That sent a powerful message to clients, Stevenson said. The excitement demonstrated to clients what they were passionate about, and goals they wanted to accomplish. They also become aware of their inner strengths. Stevenson has incorporated a number of Case Western Reserve researched and developed theories by faculty at the management school: David Cooperrider’s appreciative inquiry (building from individual or organizational strengths), Richard Boyatzis’ emotional intelligence (how skillful people are with interacting with each other) and David Kolb’s style of learning (learning by experiencing). The approach is based on the belief that humans and horses share a natural connection. In fact, Burke said, horses are a metaphor for humans who, like a herd, once lived and worked together, with each member contributing to maintaining the tribe. And, like an isolated and lonely human, horses also suffer emotional and physical problems when separated from their herds, she said.

According to Stevenson, horses developed a herd life over the last 60 million years for survival by drawing on each other’s strength, moving toward that which is positive and adapting to environmental changes. “Horses have set such good examples for how to live my life as a leader, family member, friend, potentially a wife and mother, and how to be a good social worker who embodies the profession,” Burke said. Burke and social work grad student Casey Dawson were the first to have a field placement at Spirit of Leadership. Each had to pass several requirements Stevenson set, including a love of — and experience working with — horses in their natural setting and a strong desire to help people. Burke has been riding since age 4 on her family’s rural Pennsylvanian farm, a home to six horses. After graduating from the University of Findlay as a double major in social work and a western equestrian program, Burke enrolled at the Mandel School to pursue a master’s of science in social administration degree. The opportunity for field placement at Stevenson’s farm was a major attraction. “My career goal,” said Burke, who graduates this semester, “is to take everything that I’ve learned from Jackie and the horses, and my educational experiences to set up an equine-based facility that focuses on animal-assisted therapy to promote personal discovery, growth and learning.”

Science Daily
January 7, 2014

Original web page at Science Daily


Scientists confirm functionality of emergency ventilation system for horses

Respiratory or cardiovascular arrest in outdoor animals poses a huge challenge to veterinarians. Ventilation equipment is generally hard to operate and requires electricity and compressed air. Anaesthesiologists at the University of Veterinary Medicine, Vienna (Vetmeduni Vienna) have developed an inexpensive device for the ventilation of large animals. It is easy to transport and can save animal lives in emergencies. In a recent publication in the Journal of Equine Veterinary Education the scientists confirm that their emergency ventilator works in horses. The medical treatment of horses requires not only specialized knowledge but also specialized equipment. Horses’ lungs are large and when they breathe horses take in a correspondingly large volume of air. It is not easy to supply this in an emergency. Suitable respirators are available in hospitals but are not always there when they are needed, for example in the barn, in the pasture, in the woods, during transport or at other places where emergencies can and do occur.

Yves Moens is Head of the Vetmeduni’s Clinical Unit of Anaesthesiology and Perioperative Intensive Care Medicine. He and his colleagues have long been concerned by the number of horses that die avoidable deaths because of the lack of a suitable ventilation device. The scientists have designed a ventilation pump for large animals with which veterinarians can simply and quickly resuscitate animals in the field. The device is similar to the bellows used to inflate air mattresses and is easy to carry and to use. In the event of an emergency, the vet can intubate the animal on site by inserting a breathing tube into its trachea. The ventilator pump is connected to the bellows and operated by foot. Exhalation is effected via a second valve that is manually controlled. An adult horse needs about five to six litres of air in its lungs to be able to obtain enough oxygen. A correspondingly large bellows would be too large to be operated by one man and could not be transported in a conventional car. Although the Vetmeduni’s emergency ventilator can only provide 2.5 litres of air, the researchers believed that it would be sufficient for the respiration of horses if the bellows are activated several times in quick succession. They tested this idea on five anaesthetized Haflinger horses during castration surgery in a pasture. The vets were able to show that gradual ventilation with the 2.5 litre pump is sufficient to keep the animals alive.

In recent decades, anaesthetic medicine for humans and animals has developed highly sophisticated equipment and narcotics. Researchers at the Vetmeduni are developing improved anaesthetic techniques and ventilation equipment to reduce the risks during surgery. The respiratory pump is one of the outcomes. “It improves the safety of large animals in the field, both during routine anaesthesia and in emergencies. It will also help veterinarians to provide emergency first aid in these circumstancesand respect the guidelines for good practice ,” says Moens. The respiratory pump is inexpensive and easy to use and will help veterinarians treat their patients in the field.

Science Daily
October 15, 2013

Original web page at Science Daily


Important step forward for gait analysis of horses

Gait and movement pattern are essential to the horse, whether it’s a question of the horse’s well-being, competition riding or breeding. For the first time, new research made in collaboration between University of Copenhagen and The Royal Veterinary College in the United Kingdom makes it possible to use sensors to accurately measure a horse’s movements and to quantify limb movement outside the traditional gait laboratory. This provides veterinarians as well as breeders and trainers with a number of new possibilities. The new results have just been published in the Journal of Biomechanics. Horses who develop a limp are one of the major sources of frustration for horse owners as well as vets. The same applies for Wobblers disease (ataxia) where growth abnormalities or articular process joint osteoarthritis put pressure on the spinal cord causing ataxic gait. At least one in a hundred horses develop Wobblers disease, which often leads to the horse having to be euthanized. Both lameness and Wobblers disease have an effect on a horses gait, and so far veterinarians have only been able to study horse movement in a gait-laboratory, which commonly only allows study of a few steps at a time on a straight line. Using inertial sensors; small sensors containing technology like what you find in a cellphone, i.e. gyroscopes, accelerometers and magnetometers, veterinarian and PhD from the Faculty of Health and Medical Sciences at University of Copenhagen, Dr. Emil Olsen and his collaborators from Dr. Thilo Pfau’s research group at Royal Veterinary College in the United Kingdom have managed to measure horse movement (displacement) as well as the timing of the hoof’s contact with the ground very accurately.

“Our previous research shows that inertial sensors placed right above the horse’s fetlock joint can be used to reliably determine the timing of the hoof’s contact with the ground. Furthermore, we’re a big step closer to being able to measure movement during training of a horse under real-life conditions, because we have also managed to validate the method against the reference standard motion capture, and this provides us with tools to evaluate the development and change in coordination and symmetry simultaneously,” Doctor of Veterinary Medicine and PhD Emil Olsen explains. Using this new method, veterinarians will be able to analyse the movement patterns of horses with lameness much better than before. Professional trainers will also be able to utilise the sensors, i.e. to check whether a horse actually moves rhythmically, which is an important criteria in dressage as well as other equestrian disciplines. Strictly scientific, the sensors are also quite interesting, as researchers will be able to look into the motor skills and movement patterns of horses in a much more thorough way than previously, although veterinarians are the primary target of the new method. “Our goal with this new system is to achieve a broader screening of the horse’s coordination, and through that, to be able to discover diseases and problems earlier. It will also be possible to monitor diagnostics and rehabilitation outside the gait lab with equipment economically within reach for most vets,” Emil Olsen adds.

Science Daily
September 3, 2013

Original web page at Science Daily


Pregnancy in horses: Helping horses come to term

It is not only humans that sometimes experience difficulty having children. Horses too have a low birth rate, with many pregnancies failing within the first few weeks after conception. The reason is currently unknown but recent research by the team of Christine Aurich at the University of Veterinary Medicine, Vienna (Vetmeduni) suggests that a particular class of blood cells may be involved. The results have just been made available online in the journal Reproduction, Fertility and Development. As any nervous first-time mother will confirm, the initial three months of pregnancy are the most risky time: many expectant women are reluctant to inform their friends or colleagues that they are pregnant until after this period is past. It is less well known that horses suffer from similar problems, with a considerable number of pregnancies failing to progress beyond the first five weeks. The explanation is still unclear but may relate to a problem with the mare’s immune system, as the latest work in the group of Christine Aurich in the Vetmeduni’s Centre for Artificial Insemination and Embryo Transfer strongly suggests.

The fertilized egg, or conceptus, obviously contains contributions from the stallion as well as the mare, which means it somehow has to avoid being recognized and attacked by the mare’s immune system. Horse breeders talk about maternal tolerance of the conceptus and horses — as other animals — have a variety of mechanisms to enable fertilization and a successful pregnancy. Maternal tolerance probably depends on wide-ranging changes to the maternal immune response. But what makes some mares better than others at adapting their immune systems? There are indications from work in humans and mice that a particular class of immune cell, the so-called regulatory T cells or Tregs (pronounced “tea regs”), might somehow be important in maternal tolerance. Aurich and her colleagues have now developed a highly sensitive assay to measure the proportion of Tregs in the blood of horses. They used their new technique to investigate over 100 mares that were presented for artificial insemination, correlating the results with the outcome of the resulting pregnancies. Of course, not all of the animals conceived. The scientists could find no association between the level of Tregs in the mares’ blood with the success of the insemination procedure. However, they did observe clearly lower numbers of Tregs in the blood of horses that suffered an early loss of pregnancy compared with those that either aborted much later (for whatever reason) or gave birth to live foals. The results suggest that high numbers of Tregs might somehow be required to suppress the mare’s natural immune reaction against the conceptus. In other words, low levels of Treg cells in mares might cause pregnancy loss in the five weeks after fertilization.

The differences in the levels of Tregs between horses in the “successful pregnancy” and the “unsuccessful” groups were too small to be useful to predict whether an individual mare is likely to suffer early pregnancy failure. Nevertheless, the results may help breeders solve the problem. There is evidence from human medicine that oestradiol may enhance the function of Tregs during pregnancy and treatment with this hormone could possibly benefit mares prone to losing the conceptus. Another possible course would be to expose mares to the stallion’s semen before implantation, which might increase the number of Tregs in the blood and the animal’s tolerance to the conceptus, thereby helping avoid early pregnancy losses. Aurich is optimistic: “A number of reasons have been proposed to account for early pregnancy failure in the horse but our work suggests that a low level of Tregs may actually be among the most important factors. It can only be a matter of time before we find out how to solve the problem.”

Science Daily
August 20, 2013

Original web page at Science Daily


Study finds fears that pet ponies and donkeys traded for horsemeat in Britain unfounded

Fears that pet ponies and donkeys are being traded for horsemeat are unfounded, reveals research published online in the Veterinary Record. Buyers want larger size animals to obtain the maximum meat yield, so go for thoroughbreds and riding horses, the study indicates. The researchers looked at the animals put up for sale at seven randomly selected auction markets in Britain in August and September 2011, and the type preferred by dealers buying on behalf of abattoirs. The auctions were in North Yorkshire, West Yorkshire, Wales (Powys), Berkshire and Cheshire and traded equines only, but of all types, breed and age. Their study was prompted by public concerns about the possible dispatch to slaughter of pet horses and donkeys and unwanted thoroughbred racehorses. The authors examined 384 animals, which included a broad range of cross breeds, thoroughbreds, and ponies, and found out the destination of the 294 that were sold. Ninety were either withdrawn from sale or didn’t reach their reserve price. Just 68 were bought on behalf of the three main horse abattoirs operating in Britain in 2011, while 226 were bought by other types of buyer.

Almost half of the horses and ponies put up for sale were geldings (42%), followed by mares (30%), fillies (16%), colts (10%), and stallions (2%). Height varied from 9 to 17 hands while age ranged from under 12 months to 21 years. Animals destined for the meat trade were around 2.5 times as likely to be larger — taller than 15 hands — than those bought by other outlets. Horsemeat buyers avoided ponies and cross breeds and instead opted for thoroughbreds and riding horses (43%). The price per hand for meat trade animals varied from £1.31 to £57.79. Dealers buying on behalf of abattoirs were twice as likely to purchase animals that had some physical abnormality, including flesh wounds, burn injuries, bruises, swellings, bleeding, discharge, hair loss, or deformity, as those buying for other outlets (26% compared with 13%). And 16% of the animals destined for an abattoir were lame. The authors conclude: “Equine buyers supplying horse abattoirs in Great Britain had a preference for purchasing larger animals and they avoided buying ponies. This is thought to reflect a preference for animals which provide a maximum meat yield from the carcase to cover the cost of transport, slaughter, and dressing.” They add: “A relatively small proportion of unwanted ponies and small horses were destined for the meat trade. In general, the findings from this study did not support the view that the abattoir industry focused on profiting from the slaughter of pet ponies.”

Science Daily
July 23, 2013

Original web page at Science Daily


Doctors in veterinary, human medicine team to give burned horse a second chance

The unlikely pairing of an equine veterinarian and a burn surgeon is providing a second chance at a normal life for a horse that was doused in flammable liquid and set on fire late last summer. The Ohio State University doctors and their teams have partnered to perform two skin graft procedures on the American Paint Horse named Northstar, who suffered severe burns to almost half of his body when the abuse occurred. The same instruments used in a typical human burn surgery were used for the horse’s grafting procedures. The clinicians removed ultrathin sheets of skin from Northstar’s chest and expanded them with a meshing tool before placing the grafts across an enormous wound spanning the horse’s back. When he arrived in Columbus on Sept. 5, Northstar had exposed bone at the base of his neck as a result of the burns. Skin damage extended from his neck to the base of his tail and along both of his sides. No suspect has been identified in the case. The doctors’ collaboration — not to mention the unusual size of the back wound — has provided a rare learning experience for both clinicians and their colleagues. “There’s been a lot of trial and error with the challenges of how to bandage him, what the most appropriate antiseptic is for cleaning the wound bed, and the biology of burned tissue in a horse,” said Samuel Hurcombe, assistant professor of veterinary clinical sciences and the leader of Northstar’s care team.

Veterinary experts got the healing off to a good start with relentless wound management, a series of smaller skin grafts and the implantation of cell cultures in the wound bed. These procedures were performed to bring top-layer skin tissue to the central area of the expansive wound bed on Northstar’s neck and shoulders, where all his skin had burned away. To address the large wound across the horse’s back, Hurcombe consulted longtime trauma and burn surgeon Larry Jones at Ohio State’s Wexner Medical Center. The two observed one another’s surgeries and studied human- and veterinary-medicine journal articles before teaming to accelerate Northstar’s care. Jones, associate professor of clinical surgery and director of the Burn Center at the medical center, led the two larger skin graft surgeries. Early on, he encountered a significant challenge: how deep to set the tool that would peel off the donor skin. “We want to take the top layer of skin but we also need a portion of the second layer, the dermis,” he said. After Jones consulted with Hurcombe and the two conducted more research, “I knew I had to take a graft that’s about twice as thick as one I would take if I were operating on a human.”

The team then ran the graft through a mesher that cut holes in the graft skin and allowed for expansion of the graft to about four times its original size. “When the graft takes, the holes will fill in from skin cells growing from the edges,” Jones said. They dressed the wounds with bandages containing medical-grade silver, which functions as an antibiotic, to speed healing of the grafts and the donor sites. At this stage of the horse’s recovery, more than half of the initial wound is healed, with the repair resulting from both the various skin grafting procedures and normal closure along the edges of the damaged skin. Northstar will likely undergo a series of additional sheet graft surgeries to completely heal the wound. Multiple grafts are often required for extensive human burn injuries, as well. “It’s a slow process but even in the time we’ve been caring for him, he has made remarkable progress,” said Hurcombe, a specialist in equine emergency and critical care. “From a welfare standpoint, his psychology is great and after what he’s gone through, the fact that he is still so trusting of people is pretty amazing.” While he initially appeared to be a dark horse for recovery, Northstar persevered through weeks of daily cleansing and removal of dead and infected tissue followed by the application of antiseptics, honey, aloe and silver sulfadiazine cream, a common human burn treatment, to his damaged tissue.

In yet another application of human medicine in veterinary care, the team has treated Northstar with gabapentin (sold under the brand name Neurontin), a medication used for neuropathic pain in humans, to treat the severe itching and nerve-related pain that is typical in burn patients as they recover. Northstar, who turned 7 in January, is a “young, naughty boy” and would love nothing more than to toss himself to the ground and roll on his back to scratch that persistent itch, Hurcombe said. So the horse is gently tethered to keep him standing and he wears a cradle that immobilizes his neck several hours throughout the day. He is also covered in bandages and wears what is called a full-body “sleazy” covering that is typically seen on show horses. The clinicians hope that Northstar will have a complete layer of skin coverage by his 8th birthday. The road ahead is a long one, both physicians acknowledge. The location of his back wound is a tricky one to treat because even with secure bandages from his neck to his tail, the horse anatomy in the location of the burn is such that Northstar’s every movement slightly disturbs the grafted areas. “His skin graft take is a little less than what I am used to in humans,” Jones noted. “But as Dr. Hurcombe reminds me, considering his hospital bed is in a barn, he is doing very well. “I view Northstar in the same way as I do any of my other patients. I just want him to get better and go on and live his life as a horse.”

Northstar’s owners live in northwestern Pennsylvania, where police have investigated the burning incident as a criminal case. “All the owners want is for him to be happy, pain-free and able to live his life with his pasture mates,” Hurcombe said. “He is bright and alert, he interacts with people and he can eat and drink and do all the things that a horse can normally do as far as function. And he has been telling us through his behaviors that he wants to live.”

Science Daily
July 9, 2013

Original web page at Science Daily


Stem cells boom in vet clinics

Horses, dogs and even a tiger have received the unproven therapies. Now, drug regulators plan to weigh in. Patients seeking unproven stem-cell therapies in the United States often run up against government restrictions. But Vintage ‘Vinty’ Mark of Lovettsville, Virginia, had no difficulty getting such injections to treat an injured tendon in his leg. The leg improved dramatically, and Vinty went back to training — to be a racehorse. New guidance from the US Food and Drug Administration (FDA) could, however, soon rein in veterinary uses of stem cells, a practice that has exploded in the United States over the past decade, even though most therapies are unproven. Many researchers and veterinarians say that the guidance, a draft of which the agency plans to issue by the end of the year, is overdue. But others worry that FDA interference could hamper research that could benefit animals — and their human companions. In the absence of clear regulations, the industry has burgeoned. Vet-Stem, a company based in Poway, California, has provided stem-cell treatments to more than 5,000 horses, 4,300 dogs and 120 cats since treating its first patient in 2004. Kits provided by MediVet America, based in Nicholasville, Kentucky, have been used to produce stem-cell injections for more than 10,000 horses since 2010. University veterinary departments, independently or through spin-off companies, have offered such services to thousands more animals. Veterinarians send patients’ tissue samples to the centres to have cells extracted or, increasingly, turn to kits that allow them to extract the cells in-house.

Stem cells are most often used to treat horses, dogs and cats, but clinicians have also sought to use them to repair a lumbar fracture in a Bengal tiger and arthritis in pigs. Researchers have also found stem cells in the fat of bottle­nose dolphins, raising hopes for treating the marine-mammal versions of liver disease and type 2 diabetes. “There’s not a large vet practice that’s not using them,” says Wesley Sutter, a veterinarian at Lexington Equine Surgery and Sports Medicine in Kentucky. “Some claim the treatment cures everything.” Many veterinarians offer unproven stem-cell therapies to satisfy demanding customers, says Dori Borjesson, who specializes in veterinary medicine at the University of California, Davis. “Clinicians are sucked into giving treatment” even when there’s not research to back up uses, she says. Like the treatments sought by humans, most of those used in animals involve mesenchymal stem cells (MSCs), which can mature into a wide variety of cell types, including bone and cartilage, and have been shown to have anti-inflammatory and other beneficial effects. MSCs are extracted from fat or bone marrow and can be cultured or prepared for injection in concentrated form.

The FDA’s position on the use of MSCs in humans is clear. It says that the cells are drugs and therefore must be proved safe and effective before they can be used in treatment, except under certain conditions. No MSC treatments have been approved. But the FDA has different regulations for veterinary medicine, and these do not clearly address MSCs. The agency has not approved any veterinary stem-cell therapies, but neither has it cracked down on any. This is in stark contrast to its high-profile actions against purveyors of unproven human stem-cell treatments, such as Celltex Therapeutics of Sugar Land, Texas, which treated patients with MSCs until the FDA stepped in last September. That doesn’t mean that the agency is not concerned, says Lynne Boxer, a veterinary medical officer in the FDA’s Office of New Animal Drug Evaluation in Rockville, Maryland. “As with any type of drug product, there are risks and benefits,” she says. “With stem cells, there is the potential for disease transmission and tumour formation.” She declines, however, to say whether current practices are against FDA rules, or to elaborate on what the new draft guidance is likely to contain. The guidance void is irksome, says Karl Nobert, a lawyer at Squire Sanders in Washington DC, who has represented companies seeking direction from the FDA. His concern is not just professional: he is Vinty’s former owner, and says that he saw “incredible improvement” as the horse healed, with normal tendon fibres rather than scar tissue at the injury site. Research backs up the benefits of stem-cell treatments in some applications. A 2007 double-blind study in 21 dogs showed that MSCs improved chronic osteoarthritis. A 2010 report showed that injections of tissue rich in MSCs helped damaged leg bones to heal in 12 horses. And a 2012 study, much discussed by veterinarians, showed that MSCs from bone marrow helped racehorses with tendon injuries avoid re-injury.

Researchers recognize that many studies of veterinary stem-cell treatments have a major weakness: they lack control groups or blinded evaluation, which are crucial to show whether the treatments truly make a difference. “It is exceptionally difficult to do blinded studies in our patients because the owners or trainers specifically seek an institution for stem-cell therapy,” says Lisa Fortier, a veterinary surgeon at Cornell University in Ithaca, New York, and a co-author of the 2010 cartilage study. Without controlled trials, comparisons between treated and untreated animals are difficult. Owners who have paid a few thousand dollars for a therapy are more likely to follow strict rehabilitation protocols than those who have not. They are also more likely to rush horses back into action, which would skew reported recovery time, a measure of a treatment’s effectiveness. And placebo effects — on the owners — can be powerful. “The cat looks like hell to me but the owner says: ‘She looks so great. I love stem cells’,” says Borjesson.

Many veterinarians think that studying stem-cell therapies in large animals, which are more physiologically similar to humans than the mice often used in preclinical research, could be a powerful model for medicine — if studies are done right. Borjesson is running studies (with “as much blinding as possible”) of stem-cell treatments for dry eye, another eye condition called recurrent uveitis, and inflammatory bowel disease in clients’ pet dogs. She is also collaborating with researchers in human regenerative medicine, so that her findings can inform their studies of experimental therapies. And David Frisbie, a veterinary surgeon at Colorado State University in Fort Collins, is working with doctors to apply lessons from animal stem-cell treatments to joint injuries in humans. If the pending FDA guidance clearly designates animal stem cells as drugs, veterinarians and companies who want to deploy such treatments will first have to conduct clinical trials, which Frisbie estimates could cost at least US$5 million each. Nobert, meanwhile, is optimistic that veterinary stem-cell companies and university researchers will find ways to “design creative regulatory approval strategies to streamline and expedite the review-and-approval process” — which might, in turn, influence the human stem-cell regulatory process. Still, he worries that overly stringent FDA rules about, for example, how cells are characterized, could “make the ultimate commercial price unreasonable”.

April 29, 2013

Original web page at Nature


Tick-borne encephalitis virus in horses, Austria, 2011

An unexpectedly high infection rate (26.1%) of tick-borne encephalitis virus (TBEV) was identified in a herd of 257 horses of the same breed distributed among 3 federal states in Austria. Young age (p<0.001) and male sex (p = 0.001) were positively associated with infection. Tick-borne encephalitis (TBE), which is caused by tick-borne encephalitis virus (TBEV), is a potentially fatal disease of the central nervous system, mainly in humans, but also in monkeys, dogs, and horses. Ruminants such as goats, sheep, and cattle are considered to be sporadically infected subclinically. However, they might be the source of disease in humans who consume nonpasteurized milk and milk products. TBEV-associated central nervous system disease in ruminants is rare. TBEV occurs in natural foci and is endemic to many countries in Europe and parts of central and eastern Asia. The principal vectors for transmission are ticks of the genus Ixodes. Although TBEV in humans has been studied extensively, there are only a limited number of reports on TBEV in animals, especially horses. Only 2 reports were found in the German literature on the epidemiology of TBEV infection in horses, and 1 case report was found on clinical symptoms of TBE in a mare. The purpose of this study was to determine the status of TBEV infection in a large population of a single horse breed in Austria. Serum samples from 257 horses of the same breed that were distributed among 3 federal states in Austria were obtained in April 2011 and screened by using a commercial ELISA (ID Screen West Nile Competition ELISA Kit; IDvet, Montpellier, France) for antibodies against flaviviruses. ELISA-positive serum samples were further investigated by using virus-specific neutralization assays for the 3 flaviviruses circulating in Austria (West Nile virus [WNV], Usutu virus [USUV], and TBEV). Neutralization assays were conducted independently by 2 laboratories. Results were analyzed by using SPSS version 17 software (SPSS IBM, Armonk, NY, USA). Associations of sex, age, and location with positive results were tested by using 1-way analysis of variance and tested for significance by using the χ2 test. Differences in age between horses positive or negative for flaviviruses were determined by using the Student t-test. P value <0.05 was considered significant for all analyses. The study comprised 113 (44.0%) mares, 139 (54.0%) stallions, and 5 (2.0%) geldings. The mean ± SD age of horses was 8.1 ± 6.3 years (range 1–32 years). A total of 154 (59.9%) horses were boarded in Styria, 66 (25.7%) in Vienna, and 37 (14.4%) in Lower Austria and kept in various types of housing. All 3 locations are considered areas to which WNV, USUV, and TBEV are endemic. The animals were free from clinical symptoms associated with flavivirus infections. None of the horses were vaccinated with WNV and TBEV vaccines (TBEV vaccines are not licensed for use in horses). Sixty-seven (26.1%) horses were positive for antibodies against flaviviruses by ELISA, and all 67 were positive for TBEV by virus-specific neutralization tests. Positive results were distributed among 17 mares, 49 stallions, and 1 gelding. The difference in results between sexes was significant (p = 0.001). The mean ± SD ages of horses positive and negative for TBEV antibodies were 5.9 ± 4.2 and 8.9 ± 6.7 years, respectively (p<0.001) Thirty-seven positive horses were kept in Styria, 16 in Vienna, and 14 in Lower Austria. The difference in positive results for horses at the 3 locations was not significant. Low-level cross-reactivity for WNV and USUV was observed in 9 animals. The main findings of our study were a comparatively high seropositivity rate of 26.1%, a higher prevalence of TBEV-specific antibodies in younger horses, and a higher prevalence of TBEV-specific antibodies in stallions. We expected the horses to have subclinical infections with WNV lineage 2, which was introduced recently into central Europe, including Austria. However, it is well known that WNV IgG ELISAs show cross-reactivity with other flaviviruses, necessitating the use of virus-specific neutralization assays for identification of an etiologic flavivirus. The population in our study had a 2-fold higher infection rate than that observed in a similar study in Austria in 1999 in a population of 468 horses. A partial explanation for this difference might be yearly fluctuating TBEV prevalence, as measured by diagnosed human infections ( In 1999, the lowest number) of human TBE cases was recorded in Austria (87, 79, 63, and 113 human cases were diagnosed in 2008, 2009, 2010, and 2011, respectively). A study in Germany in 2006 identified 2.9% of 240 horses with TBEV neutralizing antibodies. A more recent update on TBEV seropositivity in other animal species showed prevalence rates of 26.5% in cattle and 7.0% in sheep. This study did not detect antibodies against TBEV in 40 horses. A study on the prevalence of TBEV in dogs in Austria reported that 131 (24.0%) of 545 dogs examined had antibodies against TBEV. We did not observe any influence of location on the likelihood of TBEV seropositivity. All 3 locations are within TBEV-endemic areas ( However, none of the seropositive horses showed any clinical symptoms of an arbovirus infection at any time. Regarding age distribution, a higher proportion of younger horses (mean age 5.9 years) had antibodies against TBEV than older horses (e.g., none of the horses 15–18 and 21–32 years of age had antibodies against TBEV). Older horses were in the same pastures as young horses. This finding contrasts with results of epidemiologic studies in cattle, in which animals ≤3 years of age showed a lower prevalence of antibodies against TBEV than did older animals. Tick exposure has always been high in the investigated areas, as reported in a study conducted >10 years ago, in which 52%–93% of horses were positive for antibodies against Borrelia afzelii by immunoblotting. Most of these horses had already been infected during their first year of age and were subsequently reinfected. Thus, older horses in our study might have been infected at a young age and showed a subsequent decrease in neutralizing antibodies below the detection limit.

The reason for the high number of seropositive stallions is unclear because stallions in the study were distributed among all 3 locations, and 33 (67.3%) of 49 were boarded in boxes (individual stable compartments that limit contact with other members of the population). Mares were kept exclusively in 1 TBEV-endemic location, mainly in pastures. However, stallions were more frequently transferred to other regions (e.g., for mating), where they might have been infected because of potentially higher tick infestation rates. It is also possible that for unknown biological reasons males are more frequently affected by ticks than females, as suggested by Perkins et al. in a study on the yellow-necked mouse (Apodemus flavicollis ).We plan to conduct further experiments to elucidate why ticks seem to be more attracted to male hosts than female hosts. We observed comparatively low antibody prevalence in yearlings of both sexes, which was probably caused by decreasing, but still protective, maternally transmitted immunity. Seropositivity peaks in both sexes at 4, 7, 11, 13, and 19–20 years of age indicated infections and subsequent reinfections in certain years with higher TBEV activity. Our study suggests that horses are prone to TBEV infection. However, they remain mostly asymptomatic. Thus, horses may be considered sentinel hosts for monitoring the spread of TBEV.

Emerging Infectious Diseases
April 16, 2013

Original web page at Emerging Infectious Diseases


Distinctive virus behind mystery horse disease

For almost 100 years, veterinarians have puzzled over the cause of Theiler disease, a mysterious type of equine hepatitis that is linked to blood products and causes liver failure in up to 90% of afflicted animals. A team of US scientists has now discovered that the disease is caused by a virus that shares just 35% of its amino acid sequences with its closest-known relative. The team named it Theiler disease-associated virus (TDAV), and published the discovery in the Proceedings of the National Academy of Sciences. Led by Amy Kistler at the Novartis Institutes for BioMedical Research in Emeryville, California, the team responded to an outbreak of Theiler disease at a farm in which eight horses had suddenly developed hepatitis after being injected with an antitoxin to prevent them from developing botulism. The researchers used next-generation sequencing to analyse RNA samples from the antitoxin and from two of the horses, and assembled the complete genome of the new virus. The virus was found in every one of the eight horses, as well as in the animal (from a different farm) that was the source of the contaminated antitoxin.

“In the span of a few months, we were able to sequence and validate a virus that had gone undetected for almost a century,” says Kistler. She thinks that traditional virus-hunting techniques failed to find TDAV because they rely on strong similarities to known viruses, or on the ability to culture the mystery culprit. By contrast, her team sequenced everything in their samples — an approach “that meant we didn’t have to know what we were looking for”, she says. To better understand the role of the virus, the team inoculated four healthy horses with the contaminated antitoxin. Within ten weeks, all of them carried TDAV in their bloodstream, and one later showed rising levels of liver enzymes that suggested liver disease. Although the researchers did not purify the virus before injecting it into the horses, Pablo Murcia, a virologist from the University of Glasgow, UK, says that “they have a strong case: I will be very surprised if TDAV turns out not to be the cause of equine serum hepatitis”. “Now, a new question arises,” he says, “where does this virus come from?”.

It is also possible that there is another unknown virus behind Theiler disease. After all, human hepatitis can be caused by at least five viruses. TDAV belongs to the family Flaviviridae, which includes the viruses behind yellow fever, dengue fever and hepatitis C. It is most closely associated with a genus of newly discovered viruses called Pegivirus, and is the first of these to be convincingly linked to disease. “The challenges in culturing pegiviruses mean that we’re only now getting an understanding of how widely distributed and significant they are,” says James Wood, who studies animal infections at the University of Cambridge, UK. He hints that some studies on new pegiviruses may be published in the future.

April 2, 2013

Original web page at Nature


Exercise affects reproductive ability in horses

In the latest issue of the Journal of Animal Science, researchers at Clemson University and the University of Florida examine the impact of exercise on mare reproductive health and embryo transfer. In the study, researchers divided light-horse mares into three research groups: no exercise (control), partial-exercise and full-exercise. Their goal was to measure reproductive blood flow and embryo number and quality. Partial-exercise mares were moderately exercised for 30 minutes daily during the periovulatory period and rested after ovulation for seven days. Full-exercise mares were exercised for 30 minutes daily throughout the reproductive cycle. Results from the study showed that exercise induced greater cortisol concentrations in horses. Cortisol has been shown to have effects on reproduction. Embryo recovery rates were reduced in exercised horses compared to the control group. There was no significant difference in embryo recovery rates for partial-exercise and full exercised groups, but the partial-exercised group had the lowest embryo quality score. “This led us to conclude that exercise was just as detrimental, if not more so, to the time period just prior to and during fertilization,” said Christopher Mortensen of the University of Florida and one of the authors of the study.

The impact of exercise on early pregnancy is still an area that needs further research. Researchers are looking to study embryo quality because advancing technology has allowed embryo transfer to become a vital part of the horse industry. “What we hypothesize is the reduced hormone concentrations may be having an effect on the mare’s oocytes, meaning they are not as ‘competent’ and have a reduced ability to be fertilized, or if fertilized, compromised embryo development,” said Mortensen.

Science Daily
January 8, 2013

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