Tag: Primates

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How climate change will hurt humanity’s closest cousins

Post author By Vetscite
Post date September 13, 2016

The consequences of climate change are an increasing concern for humans around the world. How will we cope with rising sea levels and climbing temperatures? But it’s not just humans who will be affected by these worldwide shifts — it’s our closest cousins, too: monkeys, apes and lemurs.

A new Concordia study published in the International Journal of Primatology shows that the world’s primate populations may be seriously impacted by climate change.

“Our research shows that climate change may be one of the biggest emerging threats to primates, compounding existing pressures from deforestation, hunting and the exotic pet trade,” says Tanya Graham, the article’s lead author and an MSc student in the Department of Geography, Planning and Environment.

She worked with environment professor Damon Matthews from Concordia and primatology post-doctoral researcher Sarah Turner from McGill to assess the exposure and potential vulnerability of all non-human primate species to projected future temperature and precipitation changes. They found that overall, 419 species of non-human primates — such as various species of lemurs, lorises, tarsiers, monkeys and apes — will experience 10 per cent more warming than the global average, with some primate species experiencing increases of more than 1.5 degrees Celsius in annual average temperature for every degree of global warming.

The researchers also identified several hotspots of primate vulnerability to climate change, based on the combination of the number of species, their endangered status and the severity of climate changes at each location. Overall, the most extreme hotspots, which represent the upper 10 per cent of all hotspot scores, cover a total area of 3,622,012 square kilometres over the ranges of 67 primate species.

The highest hotspot scores occur in Central America, the Amazon and southeastern Brazil, as well as portions of East and Southeast Asia — prime territory for some of the globe’s best-known primates who call these areas home.

The ursine howler monkey, black howler monkey, and barbary macaque are expected to be exposed to the highest magnitude of climate change when both temperature and precipitation are considered. For example, the ursine howler monkey, found in Venezuela, will experience an increase of 1.2 degrees Celsius annually and a 5.3 per cent decline in annual rainfall for each degree of global temperature increase.

“This study highlights the vulnerability of individual species, as well as regions in which primates as a whole may be vulnerable to climate change,” says Matthews, who will present the findings of this study during the Joint Meeting of the International Primatological Society and the American Society of Primatologists in Chicago later this month.

“Our findings can be taken as priorities for ongoing conservation efforts, given that any success in decreasing other current human pressures on endangered species may also increase that species’ ability to withstand the growing pressures of climate changes,” says Graham.

“Primates are often seen as flagship species for entire ecosystems, so conservation can have important ramifications for many other species too. I hope our study will help direct conservation efforts for individual primate species in particular, but also for vulnerable ecosystems in general throughout the tropical regions inhabited by non-human primates,” adds Turner.

This study was funded in part by the Concordia Institute for Water, Energy and Sustainable Systems, the Natural Sciences and Engineering Research Council of Canada and the Fonds de recherche du Québec — Nature et technologies.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/08/160810114052.htm Original web page at Science Daily

Tags Behaviour (Ethology), Physiology (e.g. Exercise Physiology), Primates

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‘Big mama’ bonobos help younger females stand up for themselves

Post author By Vetscite
Post date August 10, 2016

Female bonobo coalitions more easily defeat aggressive males. Bullying happens in the primate world too, but for young bonobo females, big mama comes to the rescue. Japanese primatologists report in Animal Behaviour that older bonobo females frequently aid younger females when males behave aggressively towards them.

“We may have uncovered one of the ways in which females maintain a superior status in bonobo society,” says lead author Nahoko Tokuyama of Kyoto University.

In their study, Tokuyama and fellow researcher Takeshi Furuichi observed a group of wild bonobos at Wamba, Democratic Republic of the Congo.

“Primate females sometimes forge partnerships to attack others. Typically, such coalitions are formed between relatives to protect useful resources from non-relatives.” says Tokuyama. “For bonobos, females leave their birth group during adolescence, so females in a group are generally non-relative to each other. Despite this, they frequently form coalitions; a major research goal for us was to highlight the dynamics in which coalition-forming happens in non-relative individuals.”

Through four years of observation they found that all female coalitions were formed to attack males, usually after males behaved aggressively toward one or more females. They also found that older females have better chances of winning when the battle is one-one-one, and when females form alliances they always win over males. What’s more, the older females don’t play favorites; whether a younger female is friendlier with the older female has no relation to whether the older female comes to help.

Tokuyama observes that coalition-forming in female bonobos may have evolved as a way to combat male harassment. “Young females have a lower social status than males, but protection from older females seem to let young females join the group without fear of being attacked by males. By controlling aggression by males in this manner, females maintain overall superiority in the social hierarchy.

“It’s beneficial for the older females as well, because the younger females start spending more time with them in hopes of getting protection. This way, the older female can give her son more opportunities to mate with the younger females. Such partnerships might in fact be the very factor that fosters gregariousness and promotes tolerance among females.”

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/07/160719105718.htm Original web page at Science Daily

Tags Behaviour (Ethology), Primates

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Chimpanzees who travel are more frequent tool users

Post author By Vetscite
Post date August 10, 2016

Chimpanzees who travel are more frequent tool users, according to new findings from the University of Neuchâtel and the University of Geneva, Switzerland, to be published in eLife.

Hawa is a wild chimpanzee from the Budongo Forest in Uganda who burns up a lot of energy travelling, which he has learnt to replenish with a dose of honey. His friend Squibs makes less of an effort to roam and has not acquired the skills needed to enjoy this high-energy treat. This pattern was repeated in other members of the study group over seven years of observation.

A low quantity of ripe fruit also increases chimpanzees’ motivation to acquire new foraging skills, but the effect is less pronounced than travel.

“Our results show that travel fosters tool use in wild chimpanzees and it may also have been a driving force in early technological evolution by humans,” says Dr Thibaud Gruber from the University of Geneva.

The team reviewed data from nine other chimpanzee communities to confirm the pattern. Chimpanzees’ closest relative, the Bonobo, travels around the same average distance as the Sonso and other Ugandan chimpanzees and uses a similar set of tools. Gorillas and most orangutans show limited or no feeding-related tool use and spend significantly less time travelling per day on the ground compared to chimpanzees. In contrast, modern human hunter-gatherers walk on average 11.4-14.1 km per day and use many more tools than any of the great apes.

Gruber studied 70 individuals of the Sonso community of chimpanzees, Pan troglodytes schweinfurthii, known for its limited tool use behaviour. This made them ideal subjects to study how tool use emerges. The only feeding-related tools they use are folded leaves, usually to collect water, and moss to soak up mineral deposits from a clay pit. 52 of them engaged with the experiment.

“After seven years of field work, I had a massive amount of data and there was clear variation in how chimpanzees engaged with the experiment. I thought it would be interesting to analyse why,” says Gruber.

He deployed the “honey trap experiment.” The Sonso chimpanzees already used their fingers to take honey from bees’ nests, with limited success. In the “honey trap” experiment, a hole is drilled into a log and partially filled with this tempting prize so it can only be accessed with an implement. Most of the individuals who successfully extracted honey employed the community’s habitual tool, a folded leaf sponge, while two used a stick. A total of 21 instances of tool use were observed in 11 individuals.

The team reviewed the data against a whole range of variables including the quantity of ripe fruits eaten and the average daily distance the chimpanzees travelled.

“We didn’t expect travel to be that important, and were surprised that it had an even greater influence than if they fed less on their preferred food of ripe fruits,” says Gruber.

The team conclude that travel created an extra need for high-energy food while the challenge of inaccessible honey created an opportunity for innovation. The team did not analyse the potential influence of social learning to influence it. In 2011, Gruber and a colleague Catherine Hobaiter from the University of St Andrews discovered that the community’s use of moss as a sponge emerged from one individual named Nick, whose behavior was copied by a dominant female and quickly spread.

The study also reveals the influence of local ecology in the development of tool use. The Budongo Forest has provided a rich environment for chimpanzees, which could explain the previous lack of tool use in the Sonso community. However, in the last few decades, the food supply has steadily decreased.

It has been suggested that the development of tool use and sociality in early humans could likewise have been adaptive responses to heightened habitat instability caused by climate change.

“When times are changing, you have to adapt your behavior and our data illustrate that chimps will pay more attention to the possibilities offered by their environment in more demanding periods,” says Gruber.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/07/160719091722.htm Original web page at Science Daily

Tags Behaviour (Ethology), Primates

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* The story of how a touch screen helped a paralyzed chimp walk again

Post author By Vetscite
Post date July 26, 2016

The case of Reo, a male chimpanzee that learned to walk again after being paralyzed due to illness, shows how much can be done to rehabilitate animals injured in captivity. So says lead author Yoko Sakuraba of Kyoto University, in an article in Primates, the official journal of the Japan Monkey Centre published by Springer.

In their normal work, researchers of the Primate Research Institute at Kyoto University use chimpanzees’ interaction with computers and touch screens to study the cognition and perception of these primates. When Reo was paralyzed from the neck down, dedicated staff put this technology to further use by encouraging the animal to walk again. This is the first case in which a paralyzed chimpanzee has been rehabilitated through such a dedicated programme.

When Reo was 24 years old in 2006, he suddenly became paralyzed when a portion of his spinal cord became inflamed. For the first ten months thereafter, the chimpanzee was severely disabled, lying on his back. He gradually recovered enough to sit up, and could later pull himself upright by using suspended ropes. Intensive physiotherapy over a period of 41 months followed, after which he was able to climb about again using only his arms.

To aid Reo’s ultimate integration back among the other twelve animals held at the institute, his carers decided to try to get him walking again. They incorporate a computerised task in this process. This was considered an option because in his youth Reo had learnt how to perform cognitive tasks on a touch panel, and in so doing had become used to receiving food rewards whenever he succeeded at tasks presented to him.

A computer-controlled monitor was therefore placed on one wall, and cognitive tasks were again put to him. It was not plain sailing at first, and the research team had to adapt their ideas seven times before they received any cooperation from a somewhat fearful Reo. Thereafter, whenever he completed a task successfully, a food reward was placed on a tray on the opposite side of the room. This meant that Reo had to move at least two meters to reach it. To busy himself at the screen again to start a new task, he had to make the two meter return journey.

At first he did so using a rope for assistance, but gradually he started travelling in an upright seated position which resembled the side-to-side manner of a penguin walking on land. The rehabilitation sessions encouraged him to increase his movements considerably, and he started walking up to five hundred meters in a two-hour session.

“Cognitive tasks may be a useful way to rehabilitate physically disabled chimpanzees, and thus improve their welfare in captivity,” says Sakuraba, who says that euthanasia need not be the only option for animals injured in captivity.

She further notes that the personality and physical condition of each animal must be considered when designing and adjusting such a rehabilitation program.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/07/160705120143.htm Original web page at Science Daily

Tags Behaviour (Ethology), Neurology, Primates

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* Monkeys in Brazil ‘have used stone tools for hundreds of years at least’

Post author By Vetscite
Post date July 26, 2016

New archaeological evidence suggests that Brazilian capuchins have been using stone tools to crack open cashew nuts for at least 700 years. Researchers say, to date, they have found the earliest archaeological examples of monkey tool use outside of Africa. In their paper, published in Current Biology, they suggest it raises questions about the origins and spread of tool use in New World monkeys and, controversially perhaps, prompts us to look at whether early human behaviour was influenced by their observations of monkeys using stones as tools. The research was led by Dr Michael Haslam of the University of Oxford, who in previous papers presents archaeological evidence showing that wild macaques in coastal Thailand used stone tools for decades at least to open shellfish and nuts.

This latest paper involved a team from Oxford and the University of São Paulo in Brazil, who observed groups of modern capuchins at Serra da Capivara National Park in northeast Brazil, and combined this with archaeological data from the same site. Researchers watched wild capuchins use stones as hand-held hammers and anvils to pound open hard foods such as seeds and cashew nuts, with young monkeys learning from older ones how to do the same. The capuchins created what the researchers describe as ‘recognisable cashew processing sites’, leaving stone tools in piles at specific places like the base of cashew trees or on tree branches after use. They found that capuchins picked their favourite tools from stones lying around, selecting those most suitable for the task. Stones used as anvils were over four times heavier than hammer stones, and hammers four times heavier than average natural stones. The capuchins also chose particular materials, using smooth, hard quartzite stones as hammers, while flat sandstones became anvils

Using archaeological methods, the researchers excavated a total of 69 stones to see if this tool technology had developed at all over time. They dug to a depth of 0.7 metres at a site close to cashew trees where they had seen modern capuchins frequently using their stone tools. They identified the tools from inspecting the size and shape of the stones, as well as the distinctive damage on the stone surface caused by capuchin pounding. Through mass spectrometry, the researchers were able to confirm that dark-coloured residues on the tools were specifically from cashew nuts. They also carbon dated small pieces of charcoal discovered with the stones to establish the oldest were least 600 to 700 years old — meaning the tools predate the arrival of Europeans in the New World.

In the paper, the researchers estimate that around 100 generations of capuchins have used this tradition of stone tools. They compared tools used by modern capuchins with the oldest excavated examples, finding they are similar in terms of weight and materials chosen. This apparent lack of change over hundreds of years suggests monkeys are ‘conservative’, preferring not to change the technology used, unlike humans living in the same region, says the paper.

Lead author Dr Michael Haslam, from the School of Archaeology at the University of Oxford, said: ‘Until now, the only archaeological record of pre-modern, non-human animal tool use comes from a study of three chimpanzee sites in Cote d’Ivoire in Africa, where tools were dated to between 4,300 and 1,300 years old. Here, we have new evidence that suggests monkeys and other primates out of Africa were also using tools for hundreds, possibly thousands of years. This is an exciting, unexplored area of scientific study that may even tell us about the possible influence of monkeys’ tool use on human behaviour. For example, cashew nuts are native to this area of Brazil, and it is possible that the first humans to arrive here learned about this unknown food through watching the monkeys and their primate cashew-processing industry.’

Tool use by monkeys has featured in other research led by Dr Haslam in recently published papers. In a study in the Journal of Human Evolution (published in June 2016), the team noted how groups of macaques in the marine national park on Piak Nam Yai Island, Thailand, selected stones as tools to crush marine snails, nuts and crabs. They also identified 10 tools in excavations at the site, which they dated as between 10 and 50 years old. In another research paper detailing fieldwork at the same site, they say the modern macaques typically moved their tools a metre or less from where they picked them up, but the longest distance they observed was around 87m. The macaques ate nine oysters at a time, on average, and generally carried the same tool over short distances. In one case, however, the researchers saw a hungry macaque eat 63 oysters one after the other, using the same stone tool to open all the shells, says the paper.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/07/160711150920.htm Original web page at Science Daily

Tags Behaviour (Ethology), History, Primates

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Anthrax capsule vaccine completely protects monkeys from lethal inhalational anthrax

Post author By Vetscite
Post date July 12, 2016

Vaccination with the anthrax capsule–a naturally occurring component of the bacterium that causes the disease–completely protected monkeys from lethal anthrax infection, according to a study published online this week in the journal VACCINE. These results indicate that anthrax capsule is a highly effective vaccine component that should be considered for incorporation in future generation anthrax vaccines.

Bacillus anthracis, the bacterium that causes anthrax, is recognized as one of the most significant bioterrorism threats. It produces three main components that allow it to cause disease–lethal toxin, edema toxin, and capsule. During anthrax infection, the bacterium invades and grows to high concentrations in the host. The capsule surrounds the bacterium and prevents it from being ingested and destroyed by the white blood cells, thus allowing anthrax infection to progress. The toxins are thought to act mainly by damaging the body’s natural defense mechanisms.

Current human vaccines for anthrax are based on the protective antigen component of the anthrax toxins. Scientists at the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) have extensively studied protective antigen, demonstrating that protective antigen alone confers protection in animal challenge studies with both rabbits and monkeys.

However, according to senior author Arthur M. Friedlander, M.D., of USAMRIID, concerns about reliance on a single antigen–as well as the issue of protecting against anthrax strains that may be vaccine resistant–have prompted the search for additional vaccine components. Bacterial capsules are commonly used in licensed vaccines for other diseases, including certain types of pneumonia and meningitis.

Friedlander’s group had already demonstrated in published studies that the anthrax capsule plays a role in conferring protection. In their current work, the team describes testing a higher dose of the capsule vaccine in monkeys against a lethal aerosol challenge with anthrax spores. All the animals receiving the capsule vaccine survived while all non-vaccinated animals succumbed to the disease.

“In the 140-year history of research on anthrax there have been two previous types of vaccine, the last one licensed in 1970,” Friedlander said. “This new capsule vaccine is expected to work against possible vaccine-resistant strains of anthrax and to protect individuals who may not respond optimally to protective antigen alone. In addition, it could be combined with protective antigen to create a multi-component vaccine that may enhance the efficacy of protective antigen- based vaccines.”

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/06/160627125302.htm Original web page at Science Daily

Tags Primates, Vaccinology

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The primate brain is ‘pre-adapted’ to face potentially any situation

Post author By Vetscite
Post date June 28, 2016

Scientists have shown how the brain anticipates all of the new situations that it may encounter in a lifetime by creating a special kind of neural network that is “pre-adapted” to face any eventuality. This emerges from a new neuroscience study published in PLOS Computational Biology.

Enel et al at the INSERM in France investigate one of the most noteworthy properties of primate behavior, its diversity and adaptability. Human and non-human primates can learn an astonishing variety of novel behaviors that could not have been directly anticipated by evolution — we now understand that this ability to cope with new situations is due to the “pre-adapted” nature of the primate brain.

This study shows that this seemingly miraculous pre-adaptation comes from connections between neurons that form recurrent loops where inputs can rebound and mix in the network, like waves in a pond, thus called “reservoir” computing. This mix of the inputs allows a potentially universal representation of combinations of the inputs that can then be used to learn the right behaviour for a new situation.

The authors demonstrate this by training a reservoir network to perform a novel problem solving task. They then compared the activity of neurons in the model with activity of neurons in the prefrontal cortex of a research primate that was trained to perform the same task. Remarkably, there were striking similarities in the activation of neurons in both the reservoir model and the primate.

This breakthrough shows that we have taken big step towards understanding the local recurrent connectivity in the brain that prepares primates to face unlimited situations. This research shows that by allowing essentially unlimited combinations of internal representations in the network of the brain, one of them is always on hand for the given situation.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/06/160610173512.htm Original web page at Science Daily

Tags Behaviour (Ethology), Neurology, Primates

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Don’t feed the monkeys: Why your generosity is harming their health

Post author By Vetscite
Post date June 14, 2016

Tourists who feed wild monkeys in Morocco are risking the health of an endangered species by making them larger, more susceptible to disease, and more stressed, according to new research.

Behavioral ecologists compared the health of two groups of wild Barbary macaques in Ifrane National Park in the Atlas Mountains, Morocco; one which spent nearly 50 per cent of their feeding activity eating food provided by humans, and another which rarely encounter tourists and instead relied on natural food resources.

The macaques which ate food from tourists were found to have poorer quality fur, with some patches of alopecia, and also suffered from higher levels of stress hormones compared with the other group.

All the females in the non-fed group gave birth, but only a third of females in the groups of Barbary macaques frequently fed by tourists had babies. The monkeys which relied on natural food were observed to only suffer one incident of a stomach upset, while the group which received large amounts of food from tourists had 32 bouts of illness.

The study also found that the effects of feeding by tourists were different depending on sex; while males did not differ between groups in body size and fur quality, the females fed by tourists had larger body sizes, but better coat quality. However, the males suffered more from alopecia and higher stress levels. The findings are published in the journal, PLOS ONE.

The study was led by Dr Laëtitia Maréchal as part of her PhD at the University of Roehampton. Dr Maréchal, now a post-doctoral fellow in the School of Psychology, University of Lincoln, UK, said: “Barbary macaques are an endangered species and recently tourism was proposed as a potential tool for the conservation of this species in Morocco. But such tourism is currently unregulated, and feeding is a common practice; therefore regulating tourist provisioning may improve animal welfare.

“We assessed the primates’ health using a range of non-invasive measures, such as birth and survival rates, the quality of their fur, body size, occurrence of injury and disease, and stress hormone levels in fecal samples. Our findings support previous research which indicates that wildlife tourism, and particularly so-called ‘tourist provisioning’, has negative impacts on the health of wild animals.

“The study suggests that measures need to be taken to avoid causing more harm to an already endangered species. We are confident that changes will soon be made to regulate wildlife tourism in Morocco, as the Moroccan authorities and the local community have supported our study. Now tourists who encounter wildlife need to be informed that feeding wild animals is harmful, and so they should not do it.”

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/05/160520142955.htm Original web page at Science Daily

Tags Behaviour (Ethology), Nutrition, Primates

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Great apes communicate cooperatively

Post author By Vetscite
Post date June 14, 2016

Gestural communication in bonobos and chimpanzees shows turn-taking and clearly distinguishable communication styles. Human communication is one of the most sophisticated signalling systems, being highly cooperative and including fast interactions. The first step into this collective endeavour can already be observed in early infancy, well before the use of first words, when children start to engage in turn-taking interactional practices embodying gestures to communicate with other individuals. One of the predominant theories of language evolution thus suggested that the first fundamental steps towards human communication were gestures alone.

The research team of Marlen Fröhlich and Simone Pika of the Humboldt Research Group at the Max Planck Institute for Ornithology together with colleagues from the Max Planck Institute for Evolutionary Anthropology in Leipzig, the Ludwig- Maximilians-University in Munich and the Kyoto University in Japan, conducted the first systematic comparison of communicative interactions in mother-infant dyads of two different bonobo and two different chimpanzee communities in their natural environments.

The bonobos were studied over the duration of two years in the Salonga National Park and Luo Scientific Reserve in the Democratic Rebublic of Congo. The chimpanzees were observed in the Taï National Park, Côte D’Ivoire, and Kibale National Park in Uganda.

The results showed that communicative exchanges in both species resemble cooperative turn-taking sequences in human conversation. However, bonobos and chimpanzees differ in their communication styles. “For bonobos, gaze plays a more important role and they seem to anticipate signals before they have been fully articulated” says Marlen Froehlich, first author of the study.

In contrast, chimpanzees engage in more time-consuming communicative negotiations and use clearly recognizable units such as signal, pause and response. Bonobos may therefore represent the most representative model for understanding the prerequisites of human communication. “Communicative interactions of great apes thus show the hallmarks of human social action during conversation and suggest that cooperative communication arose as a way of coordinating collaborative activities more efficiently,” says Simone Pika, head of the study.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/05/160524144925.htm Original web page at Science Daily

Tags Behaviour (Ethology), Primates

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Quick test for Zika effectively detects virus in monkeys

Post author By Vetscite
Post date June 1, 2016

A novel, inexpensive method for detecting the Zika virus could help slow spread of outbreak, and potentially other future pandemic diseases

An international, multi-institutional team of researchers led by synthetic biologist James Collins, Ph.D. at the Wyss Institute for Biologically Inspired Engineering at Harvard University, has developed a low-cost, rapid paper-based diagnostic system for strain-specific detection of the Zika virus, with the goal that it could soon be used in the field to screen blood, urine, or saliva samples.

“The growing global health crisis caused by the Zika virus propelled us to leverage novel technologies we have developed in the lab and use them to create a workflow that could diagnose a patient with Zika, in the field, within 2-3 hours,” said Collins, who is a Wyss Core Faculty member, and Termeer Professor of Medical Engineering & Science and Professor of Biological Engineering at the Massachusetts Institute of Technology (MIT)’s Department of Biological Engineering.

In October 2014, Collins’ team developed a breakthrough method for embedding synthetic gene networks — which could be used as programmable diagnostics and sensors — on portable, small discs of ordinary paper.

Stirred by the then-ongoing Ebola outbreak in Africa, they demonstrated a proof-of-concept color-changing diagnostic that could screen for Ebola by embedding in paper a novel kind of synthetic biomolecular sensor designed to screen for specific RNA sequences. These RNA sequences can mark not only the genetic signatures of Ebola but also other RNA viruses including Zika, SARS, measles, influenza, hepatitis C, and West Nile fever. The team believed that one day, the method could be applied in the field to identify viruses with blood, urine or saliva samples.

However, until recently, the team’s paper-based technology has been challenged by the extremely low concentration of virus that is normally found in blood, urine and saliva. Now, using blood samples from monkeys infected with Zika virus as well as virus recovered from cells infected in the laboratory, the team has validated a next generation technique that overcomes this problem.

“The vivid images in the news stemming from the ongoing Zika crisis are heartbreaking,” said Keith Pardee, Ph.D., one of the study’s co-first authors and an Assistant Professor in the Leslie Dan Faculty of Pharmacy at University of Toronto, who was formerly a Postdoctoral Fellow at the Wyss Institute and BU. “We hope a tool like this can help reduce the impact of the outbreak until a vaccine can be developed.”

With field use in mind, Collins’ team designed a simple modular workflow comprising three steps: amplification, Zika detection, and CRISPR-Cas9-aided strain identification. CRISPR-Cas9, a gene editing mechanism derived from the immune systems of bacteria, can be used to search entire sequences to find exclusive genetic markers. Leveraging CRISPR-Cas9’s talent for sequence recognition, the third part of the team’s system uses a CRISPR-Cas9-aided paper-based diagnostic to discriminate between strains whose genetic profiles differ by as little as one nucleotide.

Once a sample’s RNA has been amplified using a mixture of enzymes and “primers,” DNA sequences that trigger replication, a drop is administered to paper discs that are freeze-dried containing a mixture of cellular components and biological proteins. The droplet of amplified RNA activates the freeze-dried components so that the discs will change color to indicate a positive result for Zika virus. While the result can be read with the naked eye similar to a home pregnancy test, a specially designed electronic reader can also be used to get faster results and could, one day, quantify the amount of viral load in a sample.

If Zika is detected, the third step involves mixing a sample with a freeze-dried CRISPR-Cas9 cocktail and then using that mixture to wet another set of color-changing paper discs. Depending on the type of Zika strain contained in the sample, these discs undergo another set of visible color changes. Although synthetic biologists and genetic engineers usually put CRISPR-Cas9 to work inside living cells, Collins’ team discovered that it functions just as well — and even better in some cases — when freeze dried.

“We have tested our diagnostic systems against closely-related strains of the Dengue virus and found that within the first two steps, our system can readily distinguish Zika from Dengue,” said Alexander Green, Ph.D., co-first author on the study and an Assistant Professor in the Center for Molecular Design and Biomimetics at ASU’s Biodesign Institute and School of Molecular Sciences, who was formerly a Postdoctoral Fellow at the Wyss Institute and BU. “The addition of the third CRISPR-based step — deploying Cas9 on a paper-based platform for the first time — only enhances the accuracy of detection. As we prepare this technology for translation, we plan to validate our system against dozens or even hundreds of clinical samples.”

All components of the diagnostic system can be freeze-dried for storage and transport while retaining their efficacy. The ability to pinpoint a strain-specific diagnosis in the field could prove valuable to national and global health organizations for tracking the spread of a viral outbreak in real time and for preparing containment strategies and treatment plans.

The diagnostic system developed by Collins’ team could be tailored to identify a range of pathogens, and is an extremely cost effective diagnostic platform given its paper-based nature. What’s more — the method is robust and could be used to quickly respond and develop new diagnostics in the face of emerging outbreaks.

“In response to an emerging outbreak, we envision a custom-tailored diagnostic system could be ready for use within one week’s time,” said Collins. “We are currently pursuing multiple opportunities to secure private and public funding in order to commercialize this diagnostic system and make it available to the world’s health responders.”

“The ability to recapitulate the genetic machinery of living cells in ordinary freeze dried paper provides a way to develop revolutionary sensors and diagnostics in a fraction of the time and with higher sensitivity and specificity than more conventional assays. These inexpensive paper-based tests also can be easily transported out of the laboratory and distributed virtually anywhere around the world. The potential for applications in health and environmental screening, particularly in low resource areas, is huge,” said Wyss Institute Founding Director Donald Ingber, M.D., Ph.D.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/05/160506132205.htm Original web page at Science Daily

Tags Neurology, Primates

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Rough childhoods have ripple effects for wild baboons

Post author By Vetscite
Post date May 17, 2016

Numerous studies have shown that childhood trauma can have far-reaching effects on adult health and survival; new research finds the same is true for wild baboons.

People who experience childhood abuse, neglect and other hallmarks of a rough childhood are more likely to develop heart disease, diabetes and other health problems later in life, even after the stressful events have passed, previous research shows.

A new study from Duke University, the University of Notre Dame and Princeton University finds that wild baboons that experience multiple misfortunes during the first years of life, such as drought or the loss of their mother, grow up to live much shorter adult lives. Their life expectancy is cut short by up to ten years compared with their more fortunate peers.

The results are important because they show that early adversity can have long-term negative effects on survival even in the absence of factors commonly evoked to explain similar patterns in humans, such as differences in smoking, drinking or medical care, said Jenny Tung, an assistant professor of evolutionary anthropology and biology at Duke who co-authored the study.

The findings, scheduled to appear online April 19 in Nature Communications, come from a long-term study of 196 wild female baboons monitored on a nearly daily basis between 1983 and 2013 near Amboseli National Park in southern Kenya.

Life isn’t easy for a wild baboon. Like many animals on the African savanna, baboons endure drought, overcrowding, disease and predation.

The researchers focused on six potential sources of early adversity. Some baboons, for example, saw very little rainfall in their first year of life, or experienced stiff competition for resources because of sibling spacing or rising numbers within their group. Others lost their mothers to death or illness, or had moms with lower rank or little social support.

More than three-fourths of the baboons in the study had at least one of the six early risk factors; 15 percent had three or more.

Baboons who lost their mothers before age four, or whose next-born sibling arrived before they were fully weaned, were found to be the most vulnerable.

For baboons, like humans, the tougher the childhood, the higher the risks of premature death later in life. Young females that experienced just one or no adverse events — a group the researchers nicknamed the “silver spoon kids” — generally lived into their late teens and early twenties, whereas those that endured three or more often died by age nine.

The “bad luck” babies not only lost more than ten years off their adult lives, they also had fewer surviving offspring. “It’s like a snowball effect,” said co-author Elizabeth Archie, associate professor at the University of Notre Dame.

Two females named Puma and Mystery, for example, were both born during years of little rainfall, and raised by low-ranking moms who died before their third birthdays. Puma eventually met her end at age seven at the jaws of a leopard. Mystery lived until her disappearance at age 14, presumably to a predator, leaving behind a single infant who died shortly thereafter.

Some researchers studying the effects of childhood stress on adult health in humans pin the blame on differences in medical care or risky behavior. People who had troubled childhoods, the thinking goes, are more likely to turn to drugs, alcohol or other coping mechanisms that are bad for their health.

But wild baboons don’t smoke or binge on junk food, and they don’t carry health insurance. This supports the idea that differences in lifestyle and medical care are only part of the story, said co-author Susan Alberts, professor of biology at Duke.

Baboon females that experienced the most misfortune in their early years were also more socially isolated as adults, suggesting that social support may also be at play.

Together with study co-author Jeanne Altmann of Princeton, the team plans to investigate how some baboons manage to overcome early adversity. It could be that those who form and maintain supportive relationships as they grow older are better able to survive and thrive, Archie said.

Baboon DNA is 94 percent similar to that of humans, which indicates these patterns could be deep-rooted in primate physiology, the researchers say. “This suggests that human adult health effects from childhood stresses are not simply products of the modern environment, but have likely been present throughout our evolutionary history,” says George Gilchrist, program director in the National Science Foundation (NSF)’s Division of Environmental Biology, which funded the research.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/04/160419083239.htm Original web page at Science Daily

Tags Behaviour (Ethology), Primates

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How a macaque’s brain knows it’s swinging

Post author By Vetscite
Post date May 17, 2016

Any organism with a brain needs to make decisions about how it’s going to navigate through three-dimensional spaces. That’s why animals have evolved sensory organs in the ears to detect if they’re rotating or moving in a straight line. But how does an animal perceive curved motion, as in turning a corner? One explanation, published April 21 in Cell Reports, from researchers looking at macaques, is that curved motion is detected when sensory neurons in the brain receiving converging information about linear and rotational movement are activated.

The parts of the ear that help macaques and humans detect motion are the same ones that help us stay balanced. Otoliths are sphere-like organs that detect linear motion and gravitational pull. In contrast, semi-circular canals specifically detect rotational movement. Information about an animal’s motion collected by these organs are then sent to the central nervous system in the brain.

It’s known that two distinct sets of neurons help us sense linear and rotational movement, but the new study identified a third set of neurons in the macaque sensory cortex that respond optimally to curved motion.

“It’s a very interesting question as to why our brain evolved this way,” says corresponding author Yong Gu, a neuroscientist at the Shanghai Institutes for Biological Sciences and Chinese Academy of Sciences. “We don’t have to have these curved motion neurons in the sensory area of the brain; the information about translation and rotation could have converged at a higher level, e.g. association cortex which is important for sensory-motor transformation and decision making. Our hunch is that representation of curved motion in sensory cortex helps animals rapidly detect this type of movement, and save the working load of the decision centres for other important neural computations.”

Gu and lab member Zhixian Cheng made their discovery by placing macaques in moving platforms and attaching brain electrodes to individual neurons to measure how often and when they fired. “People have known that linear and rotational motion converged in the sensory cortex, and we found that certain neurons fire more spikes when the linear or rotational information are available at the same time for these neurons,” Gu says. “This might have been expected, but we now propose that these neurons could represent curvilinear motion.”

The experiments also mimicked a 1997 human study in which subjects were passively moved in various motion conditions (e.g, curvilinear motion versus moving in a straight line while rotating the body) and reported analogous curved-motion sensation as long as both linear and rotation signals are present simultaneously. The current macaque neurophysiological data show extremely similar patterns, thus could account for the human psychophysical data. “This is surprising,” Gu says. “In nature, we should be able to tell these two different types of motion during active navigation. Other signals in the brain, for example, the motor command signals may help.”

The past decade has seen a surge in papers on how the body senses motion, and Gu believes there are more surprises to come. In particular, he’s interested in learning how other sensory systems play a role in how primates know where they are going.

https://www.sciencedaily/ Science Daily

https://www.sciencedaily.com/releases/2016/04/160421133645.htm Original web page at Science Daily

Tags Neurology, Primates

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Despite their small brains, ravens and crows may be just as clever as chimps, research suggests

Post author By Vetscite
Post date May 17, 2016

A study led by researchers at Lund University in Sweden suggests that ravens can be as clever as chimpanzees, despite having much smaller brains, indicating that rather than the size of the brain, the neuronal density and the structure of the birds’ brains play an important role in terms of their intelligence.

“Absolute brain size is not the whole story. We found that corvid birds performed as well as great apes, despite having much smaller brains,” says Can Kabadayi, doctoral student in Cognitive Science.

Intelligence is difficult to test, but one aspect of being clever is inhibitory control, and the ability to override animal impulses and choose a more rational behaviour. Researchers at Duke University, USA, conducted a large-scale study in 2014, where they compared the inhibitory control of 36 different animal species, mainly primates and apes. The team used the established cylinder test, where food is placed in a transparent tube with openings on both sides. The challenge for the animal is to retrieve the food using the side openings, instead of trying to reach for it directly. To succeed, the animal has to show constraint and choose a more efficient strategy for obtaining the food.

The large-scale study concluded that great apes performed the best, and that absolute brain size appeared to be key when it comes to intelligence. However, they didn’t conduct the cylinder test on corvid birds.

Can Kabadayi, together with researchers from the University of Oxford, UK and the Max Planck Institute for Ornithology in Germany, therefore had ravens, jackdaws and New Caledonian crows perform the same cylinder test to better understand their inhibitory control.

The team first trained the birds to obtain a treat in an opaque tube with a hole at each end. Then they repeated the test with a transparent tube. The animal impulse would naturally be to go straight for the tube as they saw the food. However, all of the ravens chose to enter the tube from the ends in every try. The performance of the jackdaws and the crows came very close to 100%, comparable to a performance by bonobos and gorillas.

“This shows that bird brains are quite efficient, despite having a smaller absolute brain size. As indicated by the study, there might be other factors apart from absolute brain size that are important for intelligence, such as neuronal density,” says Can Kabadayi, and continues:

“There is still so much we need to understand and learn about the relationship between intelligence and brain size, as well as the structure of a bird’s brain, but this study clearly shows that bird brains are not simply birdbrains after all!”

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/04/160426101527.htm Original web page at Science Daily

Tags Birds (pet; ornamental; prey e.g. falcons), Neurology, Primates

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* Canine influenza transmitted to cats in Midwestern shelter

Post author By Vetscite
Post date May 3, 2016

It may be called canine influenza, but Sandra Newbury, clinical assistant professor and director of the Shelter Medicine Program at the University of Wisconsin School of Veterinary Medicine, has confirmed that the virus that sickened a large number of dogs in the Midwest last year has now infected a group of cats in the region.

Newbury, in collaboration with Kathy Toohey-Kurth, virology section head at the Wisconsin Veterinary Diagnostic Laboratory, recently tested multiple cats at an animal shelter in Northwest Indiana and found them positive for the H3N2 canine influenza virus.

“Suspicions of an outbreak in the cats were initially raised when a group of them displayed unusual signs of respiratory disease,” Newbury says. “While this first confirmed report of multiple cats testing positive for canine influenza in the U.S. shows the virus can affect cats, we hope that infections and illness in felines will continue to be quite rare.”

Feline cases previously reported in South Korea suggested that the virus — which was not seen in the U.S. until 2015 — was capable of making the leap from dogs to cats. However, just one cat tested positive for H3N2 on a single occasion in the U.S. last year. In that case, no repeated sampling was done because the sample was not known to be positive until long after the cat’s symptoms had resolved.

It now appears the virus can replicate and spread from cat to cat. “Sequential sampling of these individual cats have shown repeated positives and an increase in viral loads over time,” Toohey-Kurth says, referring to the amount of virus found in any given sample.

Preliminary work to study the genetic signature of the virus shows it to be identical to the H3N2 virus that infects dogs. Researchers at WVDL are currently completing a full genetic analysis and study of the virus.

Newbury and the UW Shelter Medicine team are working closely with the animal shelter to manage the influenza outbreak. A number of dogs at the shelter have also tested positive for the virus.

“At this time, all of the infected cats have been quarantined, and no infected cats or dogs have left this shelter,” Newbury says. “We will continue to watch carefully for instances of the disease.”

Cats that have contracted the virus in the shelter have displayed upper respiratory symptoms such as runny nose, congestion and general malaise, as well as lip smacking and excessive salivation. Symptoms have resolved quickly and so far, the virus has not been fatal in cats.

Infected dogs may develop a persistent cough, runny nose and fever. Some dogs will show no symptoms, while others exhibit more severe signs of illness. The virus has been linked to some deaths in dogs, but most dogs recover with supportive care.

Dogs and cats infected with canine influenza virus should be housed separately from other animals and precautions should be taken to prevent spread of the virus on hands and clothing.

An H3N2 vaccine is now available for dogs, but no vaccine is currently approved or recommended for cats. A veterinarian can recommend whether or not to seek an H3N2 canine influenza vaccine for dogs.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/04/160401080741.htm Original web page at Science Daily

Tags Dogs, Primates, Virology

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Three new primate species discovered in Madagascar

Post author By Vetscite
Post date May 3, 2016

Immunotherapy with a live bacterium combined with chemotherapy demonstrated more than 90% disease control and 59% response rate in patients with malignant pleural mesothelioma (MPM), according to the results of a phase Ib trial presented today at the European Lung Cancer Conference (ELCC) 2016 in Geneva, Switzerland.

“Malignant pleural mesothelioma is a cancer of the lining of the lung and is rare but difficult to treat,” said Prof Thierry Jahan, professor of medicine at the UCSF Helen Diller Family Comprehensive Cancer Center in San Francisco, US. “Standard of care treatment with pemetrexed and platinum compound chemotherapy gets a 30% response rate but a modest impact on survival. So there is a clear unmet need in targeting this specific population.”

Patients with MPM strongly express the mesothelin antigen in the tumour. CRS-207 is a live, attenuated Listeria monocytogenes bacterium that contains two gene deletions to diminish its pathogenicity and has also been engineered to express mesothelin.

“In our early studies, CRS-207 induced an anti-mesothelin response and cellular tumour specific immunity in patients with mesothelin expressing tumours,” said Jahan. “We also have data suggesting that this immunotherapy works synergistically with chemotherapy, so testing the effect of this immune targeting agent with chemotherapy was a natural step.”

The current study examined the impact of CRS-207 combined with standard chemotherapy in patients with advanced unresectable mesothelioma who were candidates for chemotherapy. It included 38 patients who received two CRS-207 infusions two weeks apart, up to six cycles of pemetrexed plus cisplatin three weeks apart, followed by two additional CRS-207 infusions three weeks apart. Eligible patients received maintenance CRS-207 every eight weeks. Patients were followed every eight weeks until disease progression.

After a median follow up of 9.4 months (range: 0.2-28.1 months), the investigators found that 59% of patients had partial response and 35% had stable disease, for an overall 94% disease control rate. Median progression free survival was 8.5 months. Jahan said: “Patients receiving the combination of CRS-207 and chemotherapy had a deep response, with more than 90% disease control.”

The primary side-effects associated with CRS-207 administration were temperature spike and rigors. These were related to the infusion and resolved within 24 hours. “The safety of the agent was remarkable,” said Jahan. “It really does appear to be safe, and was well-tolerated in combination with pemetrexed and platinum chemotherapy. There didn’t seem to be any cumulative toxicity.”

Immunohistochemistry analysis in three patients showed marked recruitment and expansion of tumour infiltrating leukocytes following the administration of the therapy. There was also an enhancement of infiltrating CD8+ cells, macrophages and natural killer cells.

Jahan said: “We saw good immune activation which confirmed the preclinical hypotheses for utilising this agent. It appears to activate both innate and adaptive immunity and then develops a synergistic efficacy with the chemotherapy.”

He concluded: “CRS-207 is an exciting agent for patients with mesothelioma. Our preliminary results are encouraging, suggesting superior clinical activity when added to standard chemotherapy. This supports assessing the impact of CRS-207 in a randomised trial, which is currently in the planning stages and should be underway within this calendar year.”

Commenting on the research, Prof Rolf Stahel, Professor of oncology at the University Hospital Zurich in Zurich, Switzerland, said: “The findings suggest that the addition of this type of immunotherapy improves the response rate, and provides a longer progression free survival, compared to what would be expected with chemotherapy alone. This supports the hypothesis of benefit of this vaccination which will be examined in a randomised trial to prove or disprove the survival benefit of vaccination added to chemotherapy.”

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/04/160414113413.htm Original web page at Science Daily

Tags Neurology, Primates

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Genomes of chimpanzee parasite species reveal evolution of human malaria

Post author By Vetscite
Post date April 20, 2016

Understanding the origins of emerging diseases — as well as more established disease agents — is critical to gauge future human infection risks and find new treatment and prevention approaches. This holds true for malaria, which kills more than 500,000 people a year. Symptoms, including severe anemia, pregnancy-associated malaria, and cerebral malaria, have been linked to the parasite’s ability to cause infected red blood cells to bind to the inner lining of blood vessels.

An international team led by Beatrice Hahn, MD, a professor of Medicine and Microbiology from the Perelman School of Medicine at the University of Pennsylvania, and MD/PhD student Sesh Sundararaman, used a selective amplification technique to sequence the genomes of two divergent Plasmodium species, Plasmodium reichenowi and Plasmodium gaboni, from miniscule volumes of chimpanzee blood to find clues about the evolution and pathogenicity of Plasmodium falciparum, the deadliest malaria parasite that affects people. Their findings appear this week in Nature Communications.

African apes harbor at least six Plasmodium species that have been classified into a separate subgenus, called Laverania. Three of these Laverania species, including Plasmodium reichenowi and Plasmodium gaboni, reside in chimps, while three others, including Plasmodium praefalciparum that gave rise to Plasmodium falciparum, reside in gorillas. The gorilla origin of Plasmodium falciparum was discovered several years ago by this same international group of investigators.

“We want to know why Plasmodium falciparum is so deadly,” Hahn said. “The answer must lie in the blueprint — the genome — of its chimpanzee and gorilla cousins. We also want to know how and when the gorilla precursor of Plasmodium falciparum jumped into humans, and why this happened only once.”

Parasites infecting humans and great apes share genes that allow them to hide from the host’s immune system, adhere to tissues, and cause disease. Better understanding the evolution of human malaria virulence provides potential new targets for drugs and vaccines.

Coauthor Dustin Brisson, PhD, a professor of Biology at Penn, initially developed the selective amplification method to sequence bacterial genomes. Sundararaman calls applying this new approach to malaria research “one of the paper’s most important contributions.” Using this technique, the team was able to generate high quality Laverania genome sequences by using small amounts of unprocessed blood collected from chimpanzees living in sanctuaries during routine health screens.

The chimpanzee parasite genomes contain a goldmine of information about the evolutionary origins of the malaria parasites infecting humans. One of the first things to emerge from genome-wide analyses was that the parasites indeed represent distinct, non-interbreeding species.

In addition, members of each chimpanzee parasite species display about 10 times more genetic diversity than do human parasites. “The chimpanzee parasites really highlight the lack of diversity in Plasmodium falciparum,” said co-author Paul Sharp, PhD, an evolutionary biologist from the University of Edinburgh and long-term collaborator of the Hahn team. “This is most likely because these parasites went through a severe bottleneck when first transmitted to humans, perhaps within the past 10,000 years.”

By comparing the different parasite genomes the team also found an expansion of a multi-gene family, which governs red blood cell remodeling and therefore helps the parasite to evade host immune cells as well as clearance by the spleen. “The remodeling process is a key part of severe malaria pathology in human Plasmodium falciparum infections,” explained coauthor Julian Rayner, PhD, a malaria researcher at the Wellcome Trust Sanger Institute and long-term member of the research team. “The expansion of this gene family from a single gene in all other Plasmodium parasites to up to 21 genes in Laverania suggests that remodeling evolved early in the radiation of this group of primate parasites and contributed not only to their unique biology but perhaps also to their successful expansion.”

“‘We also found a short region of the genome, including two essential invasion genes, where Plasmodium falciparum was much more different from its close relatives than we expected,” said Lindsey Plenderleith, PhD, a postdoctoral fellow at the University of Edinburgh, who together with Sundararaman compared and annotated the various parasite genomes. Further analysis yielded the surprising finding that this fragment of DNA was horizontally transferred — from one species to another — into the gorilla ancestor of Plasmodium falciparum.

“It is tempting to speculate that this unusual event somehow predisposed the precursor of Plasmodium falciparum to colonize humans,” added Hahn. “However, this gene transfer clearly is not the entire story.”

Although the origin of Plasmodium falciparum is now well-established from past research by this group, nothing is known about the circumstances that led to its emergence. “Coaxing entire parasite genome sequences out of small quantities of unprocessed ape blood will help us to better understand what happened and whether it can happen again,” Sundararaman said.

“It’s an exciting time to study Plasmodium species that cannot be cultured and have thus been neglected because of the difficulty of obtaining sufficient quantities of DNA for whole genome sequencing,” Hahn said. The team plans, as a next step, to use the now validated select genome amplification technique to sequence additional ape parasite genomes to identify host-specific interactions and transmission requirements, thereby uncovering vulnerabilities that can be exploited to combat human malaria.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/03/160322080523.htm Original web page at Science Daily

Tags Genetics, Parasitology, Primates

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* Monkeys drive wheelchairs using only their thoughts

Post author By Vetscite
Post date April 6, 2016

Neuroscientists at Duke Health have developed a brain-machine interface (BMI) that allows primates to use only their thoughts to navigate a robotic wheelchair.

The BMI uses signals from hundreds of neurons recorded simultaneously in two regions of the monkeys’ brains that are involved in movement and sensation. As the animals think about moving toward their goal — in this case, a bowl containing fresh grapes — computers translate their brain activity into real-time operation of the wheelchair.

The interface, described in the March 3 issue of the online journal Scientific Reports, demonstrates the future potential for people with disabilities who have lost most muscle control and mobility due to quadriplegia or ALS, said senior author Miguel Nicolelis, M.D., Ph.D., co-director for the Duke Center for Neuroengineering.

“In some severely disabled people, even blinking is not possible,” Nicolelis said. “For them, using a wheelchair or device controlled by noninvasive measures like an EEG (a device that monitors brain waves through electrodes on the scalp) may not be sufficient. We show clearly that if you have intracranial implants, you get better control of a wheelchair than with noninvasive devices.”

Scientists began the experiments in 2012, implanting hundreds of hair-thin microfilaments in the premotor and somatosensory regions of the brains of two rhesus macaques. They trained the animals by passively navigating the chair toward their goal, the bowl containing grapes. During this training phase, the scientists recorded the primates’ large-scale electrical brain activity. The researchers then programmed a computer system to translate brain signals into digital motor commands that controlled the movements of the wheelchair.

As the monkeys learned to control the wheelchair just by thinking, they became more efficient at navigating toward the grapes and completed the trials faster, Nicolelis said.

In addition to observing brain signals that corresponded to translational and rotational movement, the Duke team also discovered that primates’ brain signals showed signs they were contemplating their distance to the bowl of grapes.

“This was not a signal that was present in the beginning of the training, but something that emerged as an effect of the monkeys becoming proficient in this task,” Nicolelis said. “This was a surprise. It demonstrates the brain’s enormous flexibility to assimilate a device, in this case a wheelchair, and that device’s spatial relationships to the surrounding world.”

The trials measured the activity of nearly 300 neurons in each of the two monkeys. The Nicolelis lab previously reported the ability to record up to 2,000 neurons using the same technique. The team now hopes to expand the experiment by recording more neuronal signals to continue to increase the accuracy and fidelity of the primate BMI before seeking trials for an implanted device in humans, he said.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/03/160303094320.htm Original web page at Science Daily

Tags Behaviour (Ethology), Neurology, Primates

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Novel small-molecule antiviral compound protects monkeys from deadly Ebola virus

Post author By Vetscite
Post date April 6, 2016

Rhesus monkeys were completely protected from Ebola virus when treated three days after infection with a compound that blocks the virus’s ability to replicate. These encouraging preclinical results suggest the compound, known as GS-5734, should be further developed as a potential treatment, according to research findings published in the journal Nature.

Ebola virus causes severe hemorrhagic fever in humans and nonhuman primates with high mortality rates and continues to emerge in new geographic locations, including Western Africa, the site of the largest outbreak to date. Since December 2013, over 28,600 cases have been reported in Guinea, Liberia and Sierra Leone, with over 11,300 deaths, according to the World Health Organization. Although several clinical trials have been conducted or are currently underway, there are no licensed vaccines or therapies against Ebola virus.

Travis Warren, Ph.D., a principal investigator at the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) and first author of the paper, said the work published is the result of continuing collaborations between USAMRIID and Gilead Sciences of Foster City, Calif. Scientists at the Centers for Disease Control and Prevention (CDC) also contributed by performing initial screening of the Gilead Sciences compound library to find molecules with promising antiviral activity.

That initial work identified the precursor to GS-5734, a small-molecule antiviral agent, which led to the effort by Gilead and USAMRIID to further refine, develop and profile the compound. Led by USAMRIID Science Director Sina Bavari, Ph.D., the paper’s senior author, the research team used cell culture and animal models to demonstrate the compound’s antiviral activity against several pathogens, including Ebola virus.

In animal studies, treatment initiated on day 3 post-infection with Ebola virus resulted in 100 percent survival of the monkeys. The animals also exhibited a substantial reduction in viral load and a marked decrease in the physical signs of disease.

“GS-5734 is a novel nucleotide analog prodrug. It inhibits Ebola virus by blocking the virus’s ability to replicate its own genetic material,” said Warren. “With this process inhibited, the virus can’t make copies of itself. Additionally, we saw no evidence from genetic sequence analyses that the virus was able to generate resistance to GS-5734.”

In cell culture studies, led at USAMRIID by Veronica Soloveva, Ph.D., GS-5734 was active against a broad spectrum of viral pathogens. These included Middle East Respiratory Syndrome (MERS) virus, Marburg virus, and multiple variants of Ebola virus, including the Makona strain causing the most recent outbreak in Western Africa.

“GS-5734 has several favorable characteristics for potential treatment of Ebola virus disease in humans. It is made using well-controlled chemical synthesis procedures, is stable, and can be made on a large scale,” Bavari commented. “It shows substantive post-exposure protection against Ebola virus in nonhuman primates, even when treatments were started after virus had spread to the blood in some animals.”

Taken together, the robust therapeutic efficacy observed in primates, the favorable drug-like properties, and the potential for broad-spectrum antiviral activity suggest that further development of GS-5734 for the treatment of Ebola virus and other viral infections is warranted, Bavari said.

According to Tomas Cihlar, Ph.D., of Gilead Sciences, the company is currently conducting a series of phase I clinical studies in healthy human volunteers to establish the safety and pharmacokinetic profile of GS-5734. The compound also has been provided for compassionate use to treat two patients with Ebola virus infection, both of whom were discharged from the hospital. One of them was the Scottish nurse with recrudescent disease and the other was an acutely infected newborn, thus far the last identified case of Ebola virus infection in Guinea.

“With the hope that the West African outbreak will remain under control, we are exploring alternative options for the development path of GS-5734, including potential use of the animal efficacy rule,” Cihlar said. The animal rule is a regulatory mechanism under which the U.S. Food and Drug Administration may consider efficacy findings from adequate and well-controlled animal studies of a drug in cases where it is not feasible or ethical to conduct human trials.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/03/160303120644.htm Original web page at Science Daily

Tags Pharmacology, Primates

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* Magnetoreception molecule found in the eyes of dogs, primates

Post author By Vetscite
Post date March 22, 2016

Dog-like carnivores, some primate species may have a magnetic compass similar to that of birds. Cryptochromes are light-sensitive molecules that exist in bacteria, plants and animals. In animals, they are involved in the control of the body’s circadian rhythms. In birds, cryptochromes are also involved in the light-dependent magnetic orientation response based on Earth’s magnetic field: cryptochrome 1a is located in photoreceptors in birds’ eyes and is activated by the magnetic field. Now researchers from the Max Planck Institute for Brain Research in Frankfurt have also detected cryptochrome 1 in photoreceptors in several mammalian species. Therefore, it is possible that these animals also have a magnetic sense that is linked to their visual system.

The perception of Earth’s magnetic field is used by many animal species for orientation and navigation. A magnetic sense is found in some insects, fish, reptiles, birds and mammals, whereas humans do not appear to be able to perceive Earth’s magnetic field.

The magnetic sense in migratory birds has been studied in considerable detail: unlike a boy scout’s compass, which shows the compass direction, a bird’s compass recognizes the inclination of the magnetic field lines relative to Earth’s surface. Surprisingly, this inclination compass in birds is linked to the visual system as the magnetic field activates the light-sensitive molecule cryptochrome 1a in the retina of the bird’s eye. Cryptochrome 1a is located in the blue- to UV-sensitive cone photoreceptors and only reacts to the magnetic field if it is simultaneously excited by light.

Together with colleagues from the Ludwig-Maximilians-University Munich, the Goethe University Frankfurt, and the Universities of Duisburg-Essen and Göttingen, Christine Nießner and Leo Peichl from the Max Planck Institute for Brain Research in Frankfurt investigated the presence of cryptochrome 1 in the retinas of 90 species of mammal. Mammalian cryptochrome 1 is the equivalent of bird cryptochrome 1a. With the help of antibodies against the light-activated form of the molecule, the scientists found cryptochrome 1 only in a few species from the carnivore and primate groups. As is the case in birds, it is found in the blue-sensitive cones in these animals. The molecule is present in dog-like carnivores such as dogs, wolves, bears, foxes and badgers, but is not found in cat-like carnivores such as cats, lions and tigers. Among the primates, cryptochrome 1 is found in the orang-utan, for example. In all tested species of the other 16 mammalian orders, the researchers found no active cryptochrome 1 in the cone cells of the retina.

The active cryptochrome 1 is found in the light-sensitive outer segments of the cone cells. It is therefore unlikely that it controls the animals’ circadian rhythms from there, as this control occurs in the cell nucleus which is located a considerable distance away. It is also unlikely that cryptochrome 1 acts as an additional visual pigment for colour perception. The researchers thus suspect that some mammals may use the cryptochrome 1 to perceive Earth’s magnetic field. In evolutionary terms, the blue cones in mammals correspond to the blue-to UV-sensitive cones in birds. It is therefore entirely possible that the cryptochrome 1 in mammals has a comparable function.

Observations of foxes, dogs and even humans actually indicate that they can perceive Earth’s magnetic field. For example, foxes are more successful at catching mice when they pounce on them in a north-east direction. “Nevertheless, we were very surprised to find active cryptochrome 1 in the cone cells of only two mammalian groups, as species whose cones do not contain active cryptochrome 1, for example some rodents and bats, also react to the magnetic field,” says Christine Nießner.

One possible explanation for this is that animals can also perceive the magnetic field in a different way: for example, with the help of magnetite, microscopic ferrous particles in cells. A magnetite-based magnetic sense functions like a pocket compass and does not require any light. Mole rats, which live in lightless tunnel systems, orient using this kind of compass. Birds also have an additional orientation mechanism based on magnetite, which they use to determine their position.

Many fundamental questions remain open in the research on the magnetic sense. Future studies will have to reveal whether the cryptochrome 1 in the blue cones is also part of a magnetic sense in mammals or whether it fulfils other tasks in the retina.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/02/160225105221.htm Original web page at Science Daily

Tags Dogs, Ophthalmology, Primates

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Proposal to ban imported monkeys catches scientists off guard

Post author By Vetscite
Post date March 22, 2016

Nicholas Price works to understand the brain’s fundamental functions, with a view towards developing a bionic eye. The neuroscientist uses marmosets and macaques in his experiments at Monash University’s Biomedicine Discovery Institute in Melbourne. In late January, he was shocked to discover a bill before the Australian Parliament that calls for a ban on the import of non-human primates for medical research.

Australia’s three main breeding colonies of research primates consist of several hundred macaques, marmosets and baboons. Regular imports of the animals are vital to maintain the genetic diversity of these colonies, says Price.

Senator Lee Rhiannon, a member of the Greens party, introduced the bill on 17 September last year as an amendment to Australia’s federal Environment Protection and Biodiversity Conservation Act. But because the Senate committee that deals with this piece of legislation is not usually of interest to those in the medical research community, the amendment almost slipped under the community’s radar, says Price. By the time he heard about the proposed ban, from another researcher, the window for public comment was days away from closing, though it was later extended.

As soon as they found out, Price and his Monash colleagues James Bourne and Marcello Rosa began e-mailing researchers around the world. Several institutions rushed to submit statements opposing the bill, including the Federation of European Neuroscience Societies (FENS), the Society for Neuroscience, headquartered in Washington DC, and the Basel Declaration Society, which promotes the open, transparent and ethical use of animals in research. Australia’s National Health and Medical Research Council and the Australasian Neuroscience Society also sent statements of opposition to the Senate committee.

Animal research, including that on non-human primates, “continues to be the basis for medical advances that have extended our life expectancy”, says the FENS statement, submitted on 4 February. The Society for Neuroscience’s statement, dated the same day, says that the proposed legislation would lead to “the loss of critical research resources that will be devastating for Australian science”. The committee is now in the process of considering the bill, and will report on it on 1 March, as a prelude to an eventual Senate vote.

Rhiannon, who trained as a zoologist, told Nature that the Greens are not calling for a ban on non-human primates being used in research. “There’s certainly a live debate but it’s not the party position,” she says. She calls the bill a “modest” way to improve the welfare of research animals, and, when she launched the bill last year, spoke at length about the “the cruelty during their capture, confinement and transportation”.

Price and Bourne say that cutting off access to the genetic diversity required to maintain the monkey colonies would eventually spell the end of Australian research on non-human primates. “After a while you’ll get genetic inbreeding,” says Price, “and that can lead to exacerbation of health problems that you may not be able to see until you’re a few generations down the track.” He regards non-human primate research as one of the country’s major sources of scientific innovation.

In introducing the bill, Rhiannon also said that it would ensure that Australia “does not participate in the unethical trade of wild-caught primates for use in experimentation for the research industry”. But Australian regulations already prohibit the use of wild-caught primates in medical research, says Bourne, who is chairman of the National Non-human Primate Breeding and Research Facility Board. “They have to be certified from a registered and accredited breeding facility in another country.”

Rhiannon introduced a similar bill in 2012 that never made it to a Senate vote before Parliament was dissolved ahead of a federal election. The latest bill may face a similar challenge with an election required by January 2017 at the latest. But Rhiannon says that even if it doesn’t get passed into legislation anytime soon, the bill is a way to highlight that there is a problem with the use of non-human primates, without going so far as to call for banning such research entirely.

Price says that the events have convinced him of a need to be more public about the importance of his work. “If we can demonstrate the value and outcomes, especially in medical research, then we feel that the majority of the public would be very supportive.”

Nature 530, 394 (25 February 2016) doi:10.1038/nature.2016.19419

http://www.nature.com/news/index.html Nature

http://www.nature.com/news/proposal-to-ban-imported-monkeys-catches-scientists-off-guard-1.19419 Original web page at Nature

Tags Laboratory Animal Science, Neurology, Primates

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Experimental Ebola antibody protects monkeys

Post author By Vetscite
Post date March 22, 2016

Scientists at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, and colleagues have discovered that a single monoclonal antibody–a protein that attacks viruses–isolated from a human Ebola virus disease survivor protected non-human primates when given as late as five days after lethal Ebola infection. The antibody can now advance to testing in humans as a potential treatment for Ebola virus disease. There are currently no licensed treatments for Ebola infection, which caused more than 11,000 deaths in the 2014-2015 outbreak in West Africa. The findings are described in two articles to be published online by Science on February 25.

NIAID researchers obtained and tested blood samples from a survivor of the 1995 Ebola outbreak in Kikwit, Democratic Republic of the Congo, and discovered the survivor retained antibodies against Ebola. Investigators from the Institute for Research in Biomedicine in Switzerland then isolated specific antibodies for potential use as a therapeutic for Ebola infection. Investigators from the United States Army Medical Research Institute of Infectious Diseases administered a lethal dose of Zaire ebolavirus to four rhesus macaques, waited five days, and then treated three of the macaques with daily intravenous injections of the monoclonal antibody, known as mAb114, for three consecutive days. The untreated control macaque showed indicators of Ebola virus disease and died on day nine, but the treatment group survived and remained free of Ebola symptoms.

NIAID and Dartmouth College researchers then studied how mAb114 neutralizes the Ebola virus and determined that it binds to the core of the Ebola glycoprotein, blocking its interaction with a receptor on human cells. This area of the Ebola glycoprotein, called the receptor binding domain, was previously thought to be unreachable by antibodies because it is well-hidden by other parts of the virus, and only becomes exposed after the virus enters the inside of cells. This is the first antibody to demonstrate the ability to neutralize the virus by this interaction between the virus and its cellular receptor. Together the evidence identifies a novel site of vulnerability on the Ebola virus and suggests mAb114 could be an effective therapy and warrants further exploration, according to the authors.

https://www.sciencedaily.com Science Daily

https://www.sciencedaily.com/releases/2016/02/160225153427.htm Original web page at Science Daily

Tags Primates, Virology

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Toxoplasmosis: Morbid attraction to leopards in parasitized chimpanzees

Post author By Vetscite
Post date March 8, 2016

Researchers from the Centre d’Écologie Fonctionnelle et Évolutive (CNRS/Université de Montpellier/Université Paul Valéry Montpellier 3/EPHE) have shown that chimpanzees infected with toxoplasmosis are attracted by the urine of their natural predators, leopards, but not by urine from other large felines. The study, published on 8 February 2016 in Current Biology, suggests that parasite manipulation by Toxoplasma gondii is specific to each host. It fuels an ongoing debate on the origin of behavioral modifications observed in humans infected with toxoplasmosis: they probably go back to a time when our ancestors were still preyed upon by large felines.

Parasites such as those that cause toxoplasmosis take various pathways, some of them complex, in order to develop into their adult form and reproduce in a so-called definitive host. These pathways may include stages consisting in the infection of an intermediary host. In order to pass from one such host to another, some parasites are able to induce behavioral changes in their hosts. However, this process, known as parasite manipulation, is rarely observed in mammals.

The agent of toxoplasmosis, Toxoplasma gondii, is an exception. This protozoan, which infects a wide range of species including humans, can only reproduce in felines, which become infected by ingesting a parasitized prey. Studies on mice have shown that this parasite induces olfactory modifications in parasitized rodents: unlike healthy individuals, parasitized mice appear to be attracted by the odor of cat urine, thus making it more likely for the parasite that its intermediate hosts, mice, are eaten by cats, a definitive feline host. In humans, other studies have shown changes in behavior in parasitized individuals, such as personality changes, prolonged reaction times and reduced long-term concentration. However, no beneficial effects for the parasite have been observed, since modern humans are no longer hunted by felines.

In order to understand the origin of such behavioral change in humans, the researchers performed behavioral tests based on olfactory cues on chimpanzees, humans’ closest relatives, which are still preyed upon in their natural environment by a feline: the leopard. The tests showed that, whereas uninfected individuals avoided leopard urine, parasitized individuals lost this aversion. More surprisingly, this behavioral modification is not observed when parasitized chimpanzees are exposed to the urine of felines (lions and tigers) that are not their natural predators, thus suggesting that parasite manipulation induced by Toxoplasma gondii is highly specific.

These findings fuel an ongoing debate on the origin of behavioral and olfactory modifications observed in humans: rather than being simple secondary effects of toxoplasmosis, such modifications probably go back to a time when our ancestors were still preyed upon by large felines. In addition to chimpanzees, the researchers now hope to focus on a wider range of species undergoing different predation pressures, so as to shed light on the evolutionary history of Toxoplasma gondii and unravel the circumstances under which the parasite manipulates its hosts.

http://www.sciencedaily.com/ Science Daily

http://www.sciencedaily.com/releases/2016/02/160209090622.htm Original web page at Science Daily

Tags Parasitology, Primates

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You scratch my back and I might scratch yours: The grooming habits of wild chimpanzees

Post author By Vetscite
Post date March 8, 2016

Bystanders can influence the way adult male chimpanzees establish grooming interactions according to research by anthropologists at the University of Kent.

The results challenge existing theories and bring into question the long-held assumption that patterns of social interactions in chimpanzees and other primates reflect relationships that themselves indicate a level of trust between individuals.

The research was conducted by Dr Nicholas E. Newton-Fisher and colleague Dr Stefano Kaburu from Kent’s School of Anthropology and Conservation. Published by the journal Scientific Reports (Nature Publishing Group), it reveals the clear influence of bystanders on grooming decisions, and, intriguingly, that such decisions did not appear to be based on prior grooming interactions.

It also found that with more bystanders — a larger audience — male chimps offered less grooming at the start of a bout, were more likely to abandon attempts to start a grooming interaction, and that their grooming efforts were less likely to be reciprocated.

The results suggest that the chimps’ decisions on how much to invest in grooming interactions are based at least in part on whether there are other potential social partners close by.

While it is widely held that affiliative relationships, built up over a history of previous interactions, significantly shape future interactions, this was not supported by the research.

The findings therefore add to a growing body of evidence that grooming and other forms of social interaction in non-human primates are driven by considerations of direct benefits rather than relationships based on trust.

Wild chimpanzees were an ideal species with which to conduct the research because they live in large groups, associations between individuals are fluid, and social relationships variable.

For the study, entitled ‘Bystanders, parcelling, and an absence of trust in the grooming interactions of wild male chimpanzees’, Dr Kaburu and Dr Newton-Fisher studied the behaviour of chimpanzees in a 60-strong community from the Mahale Mountains National Park, Tanzania, which has been continuously studied for over 30 years. The chimpanzees were used to human observation and grooming interactions could be recorded in detail at close range.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/02/160210110625.htm Original web page at Science Daily

Tags Behaviour (Ethology), Primates

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Effectiveness of a herpesvirus CMV-based vaccine against Ebola

Post author By Vetscite
Post date March 8, 2016

This study represents a crucial step in the translation of herpesvirus-based Ebola virus vaccines into humans and other great apes. As the latest in a series of studies, researchers at Plymouth University, National Institutes of Health and University of California, Riverside, have shown the ability of a vaccine vector based on a common herpesvirus called cytomegalovirus (CMV) expressing Ebola virus glycoprotein (GP), to provide protection against Ebola virus in the experimental rhesus macaque, non-human primate (NHP) model. Demonstration of protection in the NHP model is regarded as a critical step before translation of Ebola virus vaccines into humans and other great apes.

The study is published Monday 15th February, in the online journal from Nature publishing, Scientific Reports.

In addition to establishing the potential for CMV-based vaccines against Ebola virus, these results are exciting from the potential insight they give into the mechanism of protection. Herpesvirus-based vaccines can theoretically be made to produce their targeted protein (in this case, Ebola virus GP) at different times following vaccination. The current CMV vaccine was designed to make the Ebola virus GP at later times. This resulted in the surprising production of high levels of antibodies against Ebola virus with no detectable Ebola-specific T cells. This immunological shift towards antibodies has never been seen before for such primate herpesvirus-based vaccines, where responses are always associated with large T cell responses and poor to no antibodies.

“This finding was complete serendipity,” says Dr Michael Jarvis who is leading the project at Plymouth University. “Although we will definitely need to explore this finding further, it suggests that we may be able to bias immunity towards either antibodies or T cells based on the time of target antigen production. This is exciting not just for Ebola, but for vaccination against other infectious as well as non-infectious diseases.”

A largely untold story is the devastating effect Ebola virus is having on wild great ape populations in Africa. Although the present study administered the vaccine by direct inoculation, a CMV-based vaccine that can spread from animal to animal may be one approach to protect such inaccessible wild animal populations that are not amenable to vaccination by conventional approaches. The current study is a step forward, not only for conventional Ebola virus vaccines for use in humans, but also in the development of such ‘self-disseminating vaccines’ to target Ebola in great apes, and other emerging infectious diseases in their wild animal host before they fully establish themselves in humans.

https://www.sciencedaily.com/ Science Daily

https://www.sciencedaily.com/releases/2016/02/160215090143.htm Original web page at Science Daily

Tags Primates, Vaccinology, Virology

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* New way to detect human-animal diseases tested in lemurs

Post author By Vetscite
Post date February 23, 2016

Advances in genetic sequencing are uncovering emerging diseases in wildlife that other diagnostic tests can’t detect.

In a study led by Duke University, researchers used a technique called whole-transcriptome sequencing to screen for blood-borne diseases in wild lemurs, distant primate cousins to humans.

The animals were found to carry several strains or species of parasites similar to those that cause Lyme disease and other infections in humans. This is the first time these parasites have been reported in lemurs or in Madagascar, the only place on Earth where lemurs live in the wild outside of zoos and sanctuaries, the researchers report in the Jan. 27, 2016 issue of Biology Letters.

The approach could pave the way for earlier, more accurate detection of future outbreaks of zoonotic diseases that move between animals and people. “We can detect pathogens we might not expect and be better prepared to deal with them,” said co-author Anne Yoder, director of the Duke Lemur Center.

In 2012, Duke Lemur Center veterinarian Cathy Williams and colleagues started performing physical exams on lemurs in the rainforests surrounding a mine site in eastern Madagascar to help monitor the impacts of such activities on lemur health.

“Lemur populations are becoming increasingly small and fragmented because of human activities like mining, logging and clearing forests to make way for cattle grazing and rice paddies,” Williams said. “If an infectious disease wipes out a lemur population it could be a huge blow to the species.”

Researchers took small amounts of blood and tested them for evidence of exposure to known viruses and pathogens, but nothing turned up.

The problem is that standard diagnostic tests tend to target known pathogens, Williams said. You can check for antibodies to certain viruses, or look for specific snippets of genetic material in an animal’s blood, “but you have to know what you’re looking for.”

The end result is that new or exotic diseases often go undetected. And with hundreds of thousands of viral and bacterial species that lemurs and other mammals harbor still awaiting discovery, “we could be looking for anything,” Williams said.

Lead author Peter Larsen, senior research scientist at Duke, analyzed blood samples from six lemurs in two species, the indri and the diademed sifaka, both of which are considered critically endangered by the International Union for Conservation of Nature (IUCN).

With advances in high-throughput sequencing, the ability to read genetic code rapidly, Larsen was able to look at all the gene readouts, or RNA transcripts, that were present in each animal — an alphabet soup containing billions of nucleotide bases.

The team found more than just lemur RNA in the animals’ blood. Using computer algorithms that compared the genetic material to sequences already catalogued in existing databases, they discovered several new types of parasites that had never been reported in lemurs.

These included a new form of the protozoa responsible for babesiosis, a disease spread by bites from infected ticks, and a new kind of Borrelia closely related to the bacterium that causes Lyme disease. They also found the first known case in Madagascar of a bacterium called Candidatus Neoehrlichia, which can be deadly in humans

Further analyses revealed that the new types of Babesia and Borrelia they found didn’t begin in lemurs, but were likely introduced to Madagascar in infected pets and livestock such as cattle and then spilled over to lemurs.

The researchers don’t yet know if the new parasites are actually dangerous to lemurs. But they caution that what is infecting lemurs could potentially infect people, too. Human health officials and veterinarians in Madagascar may want to consider screening their patients to see if any test positive for the same parasites, the researchers say.

The majority of emerging infectious diseases that affect humans, including recent outbreaks of SARS, Ebola and bird flu, are zoonotic — they can spread among wildlife, domestic animals and humans.

“Next-generation sequencing will be an important tool to identify emerging pathogens, particularly vector-borne diseases,” said Barbara Qurollo, a research assistant professor at the N.C. State College of Veterinary Medicine who was not affiliated with the study.

“A clinician cannot treat an infection that he or she does not know exists,” said veterinarian and infectious diseases researcher Edward Breitschwerdt, also of the N.C. State College of Veterinary Medicine. “The kindest form of therapy is an accurate diagnosis.”

http://www.sciencedaily.com/ Science Daily

http://www.sciencedaily.com/releases/2016/01/160127121205.htm Original web page at Science Daily

Tags Genetics, Parasitology, Primates

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To find energy-rich food, like tropical ripe fruit, is a challenge for chimpanzees

Post author By Vetscite
Post date February 23, 2016

In our supermarkets we buy raspberries in winter and chestnuts in summer. But how challenging would life become, if we needed to consume large amounts of fruit for our daily meal and had to collect them ourselves? With a largely plant-based diet, simple stomachs, and the additional cost of maintaining relatively large brains, chimpanzees face a serious challenge in their daily search for energy and nutrients. Using data on the monthly availability of young leaves, unripe and ripe fruits in three tropical rain forests in East, Central and West Africa, a consortium of researchers of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, Harvard University, McGill University, the University of St. Andrews and the Université Félix Houphouët Boigny, estimated how difficult it is for chimpanzees to find food and to predict its availability in individual trees. This study reports which cognitive strategies chimpanzees can use to gain privileged access to the most energy-rich but ephemeral food.

Tropical forest habitats and their distribution have a major impact on primate evolution, since the majority of primate species and all great apes forage on food produced by tropical forest trees. Given their lack of specialized morphological and physiological dietary adaptations, great apes are, in contrast to many old world monkeys, unable to digest chemically defended forest foods such as many mature leaves and certain seeds. This increases their reliance on the consumption of energy-rich food, such as young leaves or ripe fruit, when they are available. A low percentage of ripe fruit in the diet has negative effects on female reproductive physiology, including conception, and other life history traits.

Karline Janmaat of the Max Planck Institute for Evolutionary Anthropology and her colleagues merged three sets of long-term data collected from three tropical rain forests located in East, Central, and West Africa spanning from five to 20 years and investigated the temporal fruiting patterns of rain forest trees. The researchers quantified how difficult it is for chimpanzees to find energy-rich young leaves, unripe and ripe fruit and, in particular, large ripe fruit crops in individual trees. Their study revealed a chimpanzee’s challenge is not so much to find food plants, since they are surprisingly abundant, but to find those that actually produce food. Calculations revealed that chimpanzees were 17 times more challenged to find ripe fruit, the most energy-rich food source, than unripe fruit. Moreover, trees with large crops of ripe fruit were at least nine times scarcer than other trees: in pristine forests only one large ripe fruit crop was encountered every 10 kilometers of straight-line travel, on average. In fruit scarce months no such trees were encountered.

“When I saw chimpanzees outrun others to reach feeding trees and leave their nests before sunrise to reach high-energy fruit, I realized that the persistent idea of abundance created by giant fruit trees and lush foliage was an illusion,” says Janmaat. “This unique collaboration has finally enabled us to provide evidence that explains the chimpanzees’ intriguing monitoring behaviors and to develop well-grounded hypotheses that test how clever chimpanzees are compared to other primates with less complex or smaller brains.”

Furthermore, Janmaat and colleagues found that individual trees varied tremendously in their productive output; in some extreme cases individuals bore ripe fruit more than seven times as often as other trees of the same species. Moreover, the duration during which individual trees carried more than 50 percent of ripe fruit varied widely: In the case of Sarcocephalus pobeguinii in the Taï forest, one tree produced more than half of its maximal crop during four in 53 months, while another produced only small amounts of fruit (all scores less than 50 percent) during the same 53 months. Considering that some species showed much more variation than others, the researchers think it to be likely that chimpanzees have a species-specific knowledge of fruit production histories of some individual trees. This knowledge might help them to avoid travelling towards trees that are likely empty and to optimize monitoring times.

“The sounds of the field team calling out the data leaves an impression: ‘Young leaves: zero. Immature fruit: zero. Ripe fruit: zero.’ While a preponderance of zeros poses challenges to statistical ecologists, the challenges to those who must rely on obtaining large amounts of fruit for survival are much more consequential,” says co-author Leo Polansky.

To buffer periods of food scarcity some chimpanzees use tools to crack energy rich nuts or to extract honey from underground bee nests. The results of this study indicate that there may be another way to maximize their energy intake, namely by employing a suite of cognitive mechanisms that enable them to outcompete other animals in exploiting easily accessible energy-rich and ephemeral foods, such as ripe fruit. This suite can include abilities to generalize or classify food trees, remember the relative metrics of quantity and frequency of fruit production across years, and flexibly plan return times to feeding trees to optimize high-energy food consumption in individual trees, and efficient travel between them.

“Traditionally we have been thinking that the life in the savannah is hard and that therefore our ancestors needed to become intelligent when they left the forest. Now, this view did not concur with the intelligence we see in our closest living cousin, the chimpanzees. This new study shows convincingly that the challenge of finding ripe fruit can be more demanding in the forest then we have thought before,” says Christophe Boesch, director of the Department of Primatology at the Max Planck Institute for Evolutionary Anthropology.

http://www.sciencedaily.com/ Science Daily

http://www.sciencedaily.com/releases/2016/01/160128133350.htm Original web page at Science Daily

Tags Nutrition, Primates

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Monkeys’ reaction to those who have more? Spite

Post author By Vetscite
Post date February 9, 2016

Monkeys, like humans, will take the time and effort to punish others who get more than their fair share, according to a study conducted at Yale. In fact, they can act downright spiteful.

Capuchin monkeys will yank on a rope to collapse a table that is holding a partner monkey’s food. While chimpanzees collapse their partner’s table only after direct personal affronts like theft, capuchins punish more often, even in cases where the other monkey merely had more food, according to a study published online in the journal Evolution and Human Behavior.

“One hallmark of the human species is the fact that we’re willing to make a special effort to punish those who violate social norms” said Laurie Santos, Yale psychologist and senior author of the study. “We punish those who take resources unfairly and those who intend to do mean things to others. Many researchers have wondered whether this motivation is unique to our species.”

Santos and her colleagues Kristin Leimgruber and Alexandra Rosati, now both at Harvard University, wanted to know if a distantly related primate species would punish the beneficiaries of social inequalities. Like chimpanzees, capuchins did collapse tables to punish monkeys that stole food. But they also punished beneficiaries of windfalls as well.

“Our study provides the first evidence of a non-human primate choosing to punish others simply because they have more,” said Leimgruber, first author of the paper. “This sort of ‘if I can’t have it, no one can’ response is consistent with psychological spite, a behavior previously believed unique to humans.”

“Our findings suggest that the psychological roots of human-like punishment motivations may extend deeper into our evolutionary history than previously thought.” Santos said.

http://www.sciencedaily.com/ Science Daily

http://www.sciencedaily.com/releases/2016/01/160113173513.htm Original web page at Science Daily

Tags Behaviour (Ethology), Primates

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Gene controls stress hormone production in macaques

Post author By Vetscite
Post date January 26, 2016

Some people react more calmly in stressful situations than others. Certain genes, such as the so-called COMT gene, are thought to play a role in determining our stress response. Researchers from the Vetmeduni Vienna and the University of Vienna have now studied this gene in macaques, a genus of Old World monkeys, and for the first time have shown that a specific variant of the gene is associated with higher excretion of the stress hormone cortisol. The gene variant may also influence social rank among the animals. The results were published in the journal Hormones and Behavior.

Animals that live in groups face a variety of challenging social situations. The competition for food and mating partners as well as the establishment of the social hierarchy are potential stress factors. Ralf Steinborn, Head of the Genomics Unit of the VetCore Facility for Research at the Vetmeduni Vienna, and ethologist Lena Pflüger from the Department of Anthropology at the University of Vienna, studied Japanese macaques living at Affenberg Landskron in Carinthia, Austria, to investigate how their genetic make-up influences the excretion of the stress hormones and the behaviour of the animals.

“Japanese macaques live in strict hierarchy which entails a high level of aggressive interaction. This makes them ideally suited for a study on stress behaviour,” says Pflüger.

Pflüger, first author of the study and scientific director of the Affenberg facility, studied 26 sexually mature males during the mating season, a particularly stressful time for male animals as they must compete for females. She discovered that the amount of a metabolic product of the hormone cortisol in the animals’ faeces differed across individuals. “The macaques appear to handle stressful situations differently. Some are more courageous than others. We were interested to see whether there were genetic causes for this behaviour and how genetics affects the hormonal stress reaction and social rank,” says Pflüger.

The COMT gene is one of at least 18 genes in humans that control the dopamine system in the brain. Dopamine promotes skills such as planning, decision making and problem solving. Depending on its variant, more or less of the COMT enzyme is produced from the gene, resulting in a faster or slower dopamine metabolization in the brain. Higher amounts of dopamine in the brain increase various cognitive performances but are also associated with increased stress reactions.

Steinborn and Pflüger determined the different variants of the COMT gene in Japanese macaques. This revealed that macaques with high levels of the stress hormone also possess a certain COMT variant that presumably metabolizes dopamine in the brain more slowly. The functionality of this variant and the underlying mechanism resulting in higher stress hormone levels will be determined in further studies.

“Our results indicate that animals with stress-resilient COMT variants acquire higher rank positions in the group. But a direct correlation between COMT variant and social rank has to be investigated more closely in the future,” explains Steinborn.

“The dopamine level in the brain controls various behaviours in people. On the one hand, there are the so-called warrior types. In warriors, the dopamine in the brain is metabolized more quickly. Warriors possess lower cognitive skills and are less easily stressed. The second type are worriers, who score higher in cognitive performance tests but are more easily stressed. However, the dopamine system functions like an orchestra and is not dependent on just one factor,” says Steinborn.

In the future, Pflüger and Steinborn want to study other genes that play a role in the dopamine system of non-human primates. They aim to study a variety of primate species with different social styles. Another research focus will be the functionality of the newly discovered COMT gene variant at the RNA and protein levels.

http://www.sciencedaily.com/ Science Daily

http://www.sciencedaily.com/releases/2015/12/151218085455.htm Original web page at Science Daily

Tags Behaviour (Ethology), Endocrinology, Primates

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Humans probably not alone in how we perceive melodic pitch

Post author By Vetscite
Post date January 26, 2016

Marmosets shed light on our evolutionary history, become model for studying musical ability tone deafness. The specialized human ability to perceive the sound quality known as ‘pitch’ can no longer be listed as unique to humans. Researchers at Johns Hopkins report new behavioral evidence that marmosets, ancient monkeys, appear to use auditory cues similar to humans to distinguish between low and high notes. The discovery infers that aspects of pitch perception may have evolved more than 40 million years ago to enable vocal communication and songlike vocalizations. A summary of the research will be published online in the journal Proceedings of the National Academy of Sciences on Dec. 28, 2015.

“Pitch perception is essential to our ability to communicate and make music,” says Xiaoqin Wang, Ph.D., a professor of biomedical engineering at the Johns Hopkins University School of Medicine, “but until now, we didn’t think any animal species, including monkeys, perceived it the way we do. Now we know that marmosets, and likely other primate ancestors, do.”

Marmosets are small monkeys native to South America that are highly vocal and social. Wang, an auditory neuroscientist and biomedical engineer, has been studying their hearing and vocalizations for the past 20 years. A decade ago, he says, he and his team of researchers identified a region in the marmoset brain that appears to process pitch. Nerve cells in that region, on the edge of the primary auditory cortex, only ‘fired’ after marmosets were exposed to sounds with pitch, like the shifting in high and low notes associated with a melody, not those without, such as noise. Human brains show similar activity in that region, as other researchers have reported, he notes.

What was missing was behavioral evidence that the marmosets could perceive and respond to differences in pitch the way humans do, and Wang’s laboratory group spent years developing behavioral tests and electrophysiological devices designed to monitor subtle changes in the monkeys’ neural activity. Part of their work was to train a group of marmosets to lick a waterspout only after hearing a change in pitch.

Wang says that other animal species have been reported to show pitch perception, but none have shown the three specialized features of human pitch perception. First, people are better at distinguishing pitch differences at low frequencies than high. For example, people who hear tones of 100, 200, 300 and 400 hertz played simultaneously hear four separate sounds, but they hear only one sound when tones of 1,100, 1,200, 1,300 and 1,400 hertz are played together, even though the frequency intervals are the same in both cases.

Second, humans are able to pick up on subtle changes in the spread between pitches at low frequencies or hertz, so they notice if a series of tones is increasing by 100 hertz each time and then introduces a tone only 90 hertz higher.

And third, at high frequencies, peoples’ ability to perceive pitch differences among tones played simultaneously is related to how sensitive they are to the rhythm, or timed fluctuations, of sound waves.

Through a series of hearing tests, with waterspout licks as a readout, Wang’s team, led by graduate student Xindong Song, determined that marmosets share all three features with humans, suggesting that human components of pitch perception evolved much earlier than previously thought.

The American continent, with its marmosets in place, broke away from the African land mass approximately 40 million years ago, before humans appeared in Africa, so it’s possible that this humanlike pitch perception evolved before that break and was maintained throughout primate evolution in Africa until it was inherited by modern humans. Another possibility is that only certain aspects of pitch perception were in place before the split, with the rest of the mechanisms evolving in parallel in Old and New World monkeys. According to Wang, more stringent tests are needed to determine whether existing Old World monkeys perceive pitch like humans do.

“In addition to the evolutionary implications of this discovery, I’m looking forward to what we will be able to learn about human pitch perception now that we have a primate relative we can study behaviorally and physiologically,” says Wang. “Now we can explore questions about what goes wrong in people who are tone deaf and whether perfect pitch is an inherited or learned trait.”

http://www.sciencedaily.com/ Science Daily

http://www.sciencedaily.com/releases/2015/12/151228161251.htm Original web page at Science Daily

Tags Neurology, Primates

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Monkeys in Asia harbor virus from humans, other species

Post author By Vetscite
Post date January 26, 2016

When it comes to spreading viruses, bats are thought to be among the worst. Now a new study of nearly 900 nonhuman primates in Bangladesh and Cambodia shows that macaques harbor more diverse astroviruses, which can cause infectious gastroenteritis or diarrhea in humans.

“If you are a bat, you have bat astrovirus, but if you are a monkey, you could have everything,” said Lisa Jones-Engel, a research scientist at the University of Washington National Primate Research Primate Center and a co-author of the study, published in PLOS Pathogens.

This research, the scientists said, is the first to show evidence of human astroviruses in animals, and among the earliest to demonstrate that astroviruses can move between mammalian species.

Astroviruses from a number of species, including human, bovine, bird, cow and dog, were detected in monkeys, This “challenges the paradigm that AstV (astrovirus) infection is species-specific,” the authors wrote.

It is still unknown whether these viruses are two-way and can be transmitted to humans. They did find evidence that, in monkeys, two species of astrovirus recombined.

Knowing that nonhuman primates can harbor diverse astroviruses — including novel, recombinant viruses that may be pathogenic and/or more efficiently transmitted — highlights the importance of continued monitoring, the authors said.

This is particularly true in countries such as Bangladesh and Cambodia, where macaques and humans live side-by-side.

“This study is an example of the concept of One Health for new viruses,” noted author Stacey Schultz-Cherry at St. Jude Children’s Research Hospital in Memphis. “This is an indication that we really need to think about animal partners in One Health.”

Astroviruses are most commonly associated with diarrhea. They can also cause clinical diseases such as nephritis, hepatitis and encephalitis. Astroviruses also can be asymptomatic, depending on the species, the researchers reported. Currently, the only treatment is oral rehydration.

In this study of 879 samples of primate feces, 68 (7.7 percent) were positive for astroviruses. The majority of the positive samples (72 percent) were 79-100 percent similar to astroviruses associated with human infections; 23.5 percent of the samples were similar to mammalian astroviruses isolated from diverse animal hosts including dogs, pigs and sheep. Slightly more than 4 percent of the positive samples were associated with avian astroviruses.

The team also collected blood samples, which confirmed that more than 25 percent of the monkeys had been infected with human astroviruses.

Whether the monkeys were getting sick from these viruses is unknown. The researchers said more study is needed to determine if astrovirus infections in nonhuman primates are associated with clinical disease, or whether such infections are asymptomatic. They said none of monkeys sampled in the study appeared to have clinical disease (e.g., diarrhea) at the time of sampling.

The scientists said they are currently working on analyses to model the ecological role that nonhuman primates play in maintaining the diversity of astroviruses, particularly in places where they share the environment with humans and other animals.

http://www.sciencedaily.com/ Science Daily

http://www.sciencedaily.com/releases/2015/11/151105152107.htm Original web page at Science Daily

Tags Primates, Virology