Koala stress linked to disease threat

Many koalas in the study were successfully treated for Chlamydia before being released back into the wild.
Photo Credit: Currumbin Wildlife Hospital

Researchers have revealed a clear relationship between stress and increased disease risk in koalas in South East Queensland and on the New South Wales North Coast.

A study led by Dr Michaela Blyton at The University of Queensland measured and tracked the level of koala retrovirus (KoRV) in groups of captive and wild koalas.

“We wanted to see what happened to their KoRV loads over time and how it related to chlamydial infection and levels of the stress hormones cortisol and corticosterone in their feces,” Dr Blyton said.

“Virus load likely weakens the immune system, so those with a higher KoRV load are more at risk of diseases such as Chlamydia which can cause blindness, infertility and death.

“Poor quality or disappearing habitat may increase stress and the koalas with higher average cortisol levels had higher average KoRV loads.

Research Finds Dairy Farmers Receptive to Methane-Reducing Seaweed Feed

New research led by the University of New Hampshire examines the receptiveness of organic dairy farmers across Maine to pay an average of 64 cents more per cow per day to use methane-reducing seaweed-based feed to their cows, similar to those shown here.
Photo Credit: University of New Hampshire

New England’s dairy industry continues to evolve in response to significant market challenges that include a decreased demand for milk and higher production and land costs. However, there is also ongoing evidence that organic dairy farming can provide environmental benefits — such as reducing methane emissions — which could further differentiate their products as well as help qualify farms for new government initiatives to reduce methane through innovative management practices. Researchers from the University of New Hampshire collaborated with researchers in Maine to find evidence that nearly half of organic dairy farmers would be willing to pay a little extra for methane-reducing seaweed feed but would only consider if it was cost effective, aligned with existing feeding practices and would qualify them for government policies and subsidies.     

“Dairy farmers aim to run their farms as lucrative enterprises,” said Andre Brito, associate professor of dairy cattle nutrition and management and a scientist at UNH’s New Hampshire Agricultural Experiment Station. “The additional cost would require serious considerations, as well as more data and an effective implementation of carbon markets in the future.” 

Cats with MDR1 mutation at risk of severe reactions to popular medication

Photo Credit: Zhang Kaiyv

More than half a million cats in the United States could be at risk of a severe or even fatal neurological reaction to the active ingredient in some top-selling parasite preventatives for felines.

While the ingredient, eprinomectin, which is found in products like NexGard COMBO and Centragard, appears safe and effective for the significant majority of cats when used at label doses, a study conducted by Washington State University’s Program for Individualized Medicine identified a risk of severe adverse effects in cats with the MDR1 genetic mutation. Genetically affected cats lack a protective mechanism that prevents certain drugs, including eprinomectin, from entering the brain and causing serious neurological toxicity.

“Almost every week we receive reports about someone’s pet cat having serious reactions to eprinomectin. This is not an issue with the drug itself — the problem lies in the genes of 1% of cats. That is a sizable number considering there are over 60 million pet cats in the U.S., and we’re trying to increase general awareness of these risks,” said Dr. Katrina Mealey, a WSU veterinarian and pharmacologist who led the research.

The future of canine stem cell therapy: unprecedented, painless, and feeder-free

Generating canine induced pluripotent stem cells (iPSCs) without using feeder cells   Scientists created canine iPSCs from urine-derived cells with great efficiency     
Illustration Credit: Shingo Hatoya, Osaka Metropolitan University

Dog owners may need to learn to appreciate their best friend’s urine. Scientists at Osaka Metropolitan University have devised an efficient, non-invasive, and pain-free method to reprogram canine stem cells from urine samples, bringing furry companions one step closer to veterinary regenerative treatment.

Induced pluripotent stem cells (iPSCs) have been widely employed in studies on human generative medicine. With the growing importance of advanced medical care for dogs and cats, there is an expectation that new therapies utilizing iPSCs will be developed for these companion animals, just as they have been for humans. Unfortunately, canine somatic cells exhibit lower reprogramming efficiency compared to those of humans, limiting the types of canine cells available for generating iPSCs. IPSC induction often involves using feeder cells from a different species. However, considering the associated risks, minimizing xenogeneic components is often advisable, signifying the need to improve the efficiency of reprogramming various types of canine cells in dogs without using feeder cells.

Zika Infection in Pregnant Macaques Slows Fetal Growth

Female rhesus macaque monkeys and infants at the California National Primate Research Center at UC Davis.
Photo Credit: Courtesy of University of California, Davis

Zika virus infection in pregnant rhesus macaques slows fetal growth and affects how infants and mothers interact in the first month of life, according to a new study from researchers at the California National Primate Research Center at the University of California, Davis. The work, published Oct. 25 in Science Translational Medicine, has implications for both humans exposed to Zika virus and for other viruses that can cross the placenta, including SARS-CoV2, responsible for the COVID-19 pandemic.

“Initially I thought this was a story about Zika, but as I looked at the results, I think this is also a story about how fetal infections in general affect developmental trajectories,” said Eliza Bliss-Moreau, professor of psychology at UC Davis and senior author on the paper.

In most people, Zika virus infection causes mild or no symptoms and leaves long-lasting immunity. But during pregnancy, the virus can cross the placenta and cause damage to the nervous system of the fetus. In extreme cases, it can cause microcephaly in humans.

Scientists uncover cause of mysterious deaths of elephants in Zimbabwe

Photo Credit: Charl Durand

During this unique study, scientists from the Victoria Falls Wildlife Trust, the Animal and Plant Health Agency UK, the University of Surrey and laboratories in South Africa investigated the mysterious deaths of 35 elephants mostly between August and September 2020, in a 40 x 25 km radius of North-Western Zimbabwe. This incident followed the death of approximately 350 elephants in neighboring northern Botswana from May to June 2020, which triggered much international concern. 

African savanna elephants are an endangered species with only 350,000 remaining in the wild and ongoing losses estimated at eight percent annually. This finding is very worrying since elephants are on the International Union for Conservation of Nature red list already. Investigating the deaths of these elephants is crucial to sustaining the future of this majestic species. 

Identifying biosecurity to prevent CWD transmission

Photo Credit: Minnesota Board of Animal Health

As chronic wasting disease (CWD) ravaged deer populations across the country in recent years, studies have primarily focused on how CWD can jump from farmed herds to wild deer, with little attention given to how transmission may occur from wild deer to those living on farms. University of Minnesota researchers recently assessed the risks associated with the introduction of CWD to farmed deer herds in Minnesota, Pennsylvania and Wisconsin. Because CWD is highly infectious and sometimes fatal disease for deer with no treatment or vaccination available, strategies to prevent its spread are primary tools available to keep these animals healthy.

The study, published in Preventive Veterinary Medicine, examined various transmission pathways and their associated risk factors for farmed deer herds. The researchers collected data from 71 herds in three states, including both CWD-infected and disease-free herds. The data included deer movements, regulatory violations, CWD test results and distances to infected wild deer. They also interviewed deer farmers about their management practices.

Gut bacteria found in wild wolves may be key to improving domestic dogs’ health

Photo Credit: Nicky Pe

Gut microbes found in wild wolves may be the key to alleviating a debilitating gastrointestinal condition common to domestic dogs, according to a study led by researchers at Oregon State University – Cascades.

In a paper published in Applied Microbiology, the authors report a novel strain of Paenibacillus bacteria with characteristics of a probiotic – an organism that conveys a health benefit to the host.

In this case, the benefit would be to head off canine inflammatory bowel disease, a chronic illness characterized by vomiting, reduced appetite, weight loss, flatulence, a rumbling stomach and/or abdominal discomfort, said Bruce Seal of OSU-Cascades’ biology program.

“At present there is no known cure for this ongoing dysbiosis of the gastrointestinal tract, and there are limited options for treatment,” Seal said. “Underlying causes of the condition include an animal’s genetics, environmental factors, the immunological state of the GI tract and, maybe most importantly, an altered gut microbiome.”

Researchers Identify Genetic Makeup of New Strains of West Nile

This study shows the variety of strains in circulation and what mosquitoes may be carrying as we head into summer
Photo Credit: Jimmy Chan

Researchers at Connecticut Veterinary Medical Diagnostic Laboratory (CVMDL) located in UConn’s College of Agriculture, Health and Natural Resources identified the genetic makeup of strains of West Nile virus found in an alpaca and a crow.

These findings were published in Frontiers in Veterinary Science.

In 2021, eight cases of West Nile virus were brought to the CVMDL for diagnosis – seven birds, both domestic and wild – and one alpaca.

“We decided to pursue some research avenues through these diagnostic cases because we had an interesting cohort of West Nile cases that had come through that fall,” says Natalie Tocco ’23 (CAHNR), a resident in anatomic pathology the Department of Pathobiology and Veterinary Science.

Of the eight cases, the alpaca from Massachusetts and a crow from Connecticut had the highest amount of virus in their systems at the time of diagnosis.

Focusing on these two cases, the researchers were interested in seeing if there were genetic differences between the viruses because they occurred in different species in different states.

Gene-edited calf may reduce reliance on antimicrobials against cattle disease

 Brian Vander Ley, associate professor in the University of Nebraska–Lincoln’s School of Veterinary Medicine and Biomedical Sciences, works with Ginger, a Gir cow gene-edited with resistance to bovine viral diarrhea virus.
Photo Credit: Craig Chandler | University Communication and Marketing

Cattle worldwide face major health threats from a highly infectious viral disease that decades of vaccinations and other precautions have failed to contain. Federal, private-sector and Husker scientists are collaborating on a new line of defense, by producing a gene-edited calf resistant to the virus.

If follow-up research confirms its efficacy, the gene-editing approach offers long-term potential to reduce antimicrobial and antibiotic use in the cattle industry.

The bovine viral diarrhea virus devastates the bovine immune system and can cause severe respiratory and intestinal harm to infected beef and dairy cattle, said veterinary epidemiologist Brian Vander Ley, an associate professor in the University of Nebraska–Lincoln’s School of Veterinary Medicine and Biomedical Sciences.

In utero calves are especially vulnerable to infection. If they survive, they can remain infected for life, repeatedly spreading the virus to other cattle.

“They show up as normal cattle but really, they’re shedding a tremendous amount of virus. They’re the ‘Typhoid Marys’ of BVDV spread,” said Vander Ley, assistant director of UNL’s Great Plains Veterinary Educational Center in Clay Center.

Researchers map the genome of the world’s grumpiest cat

The mighty roar of a grumpy and angry Pallas' cat (Otocolobus manul)
Photo Credit: Johannes Heel

University of Minnesota researchers recently led successful efforts to build the first genome for Pallas’s cat (Otocolobus manul), a small wild cat native to central Asia known for its grumpy facial expression. The cat, which faces growing challenges from climate change, habitat fragmentation, and poaching, had no available genetic resources to help with conservation prior to this study. 

The study, published in NAR Genomics and Bioinformatics, was led by Nicole Flack, a doctoral candidate in the College of Veterinary Medicine, along with Christopher Faulk, a professor in the College of Food, Agricultural, and Natural Resource Sciences. 

The researchers used blood samples from Tater, a 6-year-old Pallas’s cat who lives at the Utica Zoo in New York, to construct a high-quality diploid nuclear genome assembly, a representative map of genes for the species.

The study results include confirmation that the Pallas’s cat is more closely related to certain wild cat species and less related to house cat species than some previous studies have suggested. 

Researchers Identify a New Genetic Culprit in Canine Bladder Cancers

Photo Credit: Lucie Helešicová

Researchers have identified new genetic mutations linked to a subset of canine bladder cancers. Their findings have implications both for early cancer detection and for targeted treatments in dogs and humans.

Previous research showed that 85% of canine urothelial carcinomas (a type of bladder cancer) share a specific mutation in a gene named BRAF. This mutation (known as V595E) is caused by an error in BRAF’s genetic code, where a normal ‘T’ nucleotide in the DNA sequence is substituted by an ‘A’. The BRAF V595E mutation results in abnormal activation of a genetic signaling pathway called MAPK, leading to uncontrolled cellular growth, or proliferation.

“Essentially, BRAF V595E generates an abnormal protein that instructs the cells to keep dividing, forming a tumor. So, if this single nucleotide substitution in the BRAF gene is detected in 85% of all canine urothelial carcinomas, why is it not in all of them?” asks Matthew Breen, Oscar J. Fletcher Distinguished Professor of Comparative Oncology Genetics at North Carolina State University and corresponding author of the research. “Pathologists see no difference between those cancers with this mutation and those without, so what’s going on with that other 15%?”

Lack of canine COVID-19 data fuels persisting concerns over dog-human interactions

A research literature review by Purdue University researchers published in the journal Animals highlights unanswered questions about the COVID-19 virus dynamics between dogs and humans.
 Photo Credit: Purdue Agricultural Communications photo/Tom Campbell

Early COVID-19 pandemic suspicions about dogs’ resistance to the disease have given way to a long-haul clinical data gap as new variants of the virus have emerged.

“It is not confirmed that the virus can be transmitted from one dog to another dog or from dogs to humans,” said veterinarian Mohamed Kamel, a postdoctoral fellow at Purdue University.

During the pandemic’s early days, dogs seemed resistant to the coronavirus, showing little evidence of infection or transmission, said Mohit Verma, assistant professor of agricultural and biological engineering and Purdue’s Weldon School of Biomedical Engineering. “As the virus evolved, or maybe the surveillance technology advanced, there seem to be more instances of potentially asymptomatic dogs.”

These are among the findings that Kamel, Verma and two co-authors summarized in a research literature review “Interactions Between Humans and Dogs in the COVID-19 Pandemic.” The summary, with recent updates and future perspectives, recently appeared in a special issue of the journal Animals on Susceptibility of Animals to SARS-CoV-2.

Canine distemper now threatens big cats in Nepal

 A Bengal tiger in the jungle. Although researchers have suspected distemper was infecting tigers and leopards, a new study is the first definitive proof of infection in Nepal’s big cats.
Photo Credit: R. Gilbert

Researchers with the College of Veterinary Medicine have confirmed the first cases of canine distemper virus (CDV), which can cause fatal neurological disease, in tigers and leopards in Nepal.

“Canine distemper virus has been repeatedly identified as a threat to wild carnivores and their conservation,” said Martin Gilbert, Cornell Wildlife Health Center wild carnivore health specialist and associate professor of practice in the Department of Population Medicine and Diagnostic Sciences. “This study is a first step to understanding the potential impact for Nepalese tiger and leopard populations.”

Although researchers have suspected distemper was infecting these species, the study, published Jan 28 in the journal Pathogens, is the first definitive proof of infection in Nepal’s big cats. The survey found 11% of tigers (three out of 28) and 30% of the leopards (six out of 20) had antibodies to CDV, indicating prior infection with the virus.

Relatively little is known about the status of Nepal’s leopards, but scientists believe the population is in decline due to a combination of poaching, habitat loss and human-wildlife conflict. Leopards also face increasing competition for space due to the expansion of the country’s tiger population. Could CDV push them even further into decline?

Genetic test can detect deadly bleeding disorder in dogs

Jenna, a Scottish deerhound owned by Laura Studer, has a DNA sample taken from her in Gig Harbor.
 Photos Credit: WSU College of Veterinary Medicine/Ted S. Warren.

A new genetic test can identify dogs at risk of a potentially deadly disorder resulting in excessive bleeding and bruising in the hours and days following surgical procedures.

A team led by Washington State University researchers developed the DEPOHGEN (TM) test following a study in which they examined Scottish deerhounds and identified a gene associated with the condition known as delayed postoperative hemorrhage or DEPOH. Animals with a mutation in the DEPOH gene are significantly more likely to experience the condition. The study was published in the Journal of Veterinary Internal Medicine.

“Dogs with the DEPOH mutation have a much higher risk than other dogs of developing this after undergoing surgery,” said Dr. Michael Court, the study’s corresponding author. “The DEPOHGEN test will allow us to prevent delayed postoperative hemorrhage by administering antifibrinolytic drugs to dogs that test positive for the gene before any surgery.”

Delayed postoperative hemorrhage was first recorded in greyhounds, but it has also been noted in other sighthound breeds, like Scottish deerhounds and Irish wolfhounds. Following the identification of the DEPOH gene, the team examined samples from WSU’s pet DNA bank and discovered the mutation in additional sighthounds, like Italian greyhounds and salukis, as well as in some other popular breeds, such as golden retrievers and border collies.

Rates of hatching failure in birds almost twice as high as previously estimated

Hatching failure rates in birds are almost twice as high as experts previously estimated, according to the largest ever study of its kind.
Photo Credit: Michaela Wenzler

New study from the University of Sheffield, IoZ, and UCL found more than one in six bird eggs fail to hatch. Hatching failure increases as species decline, so the new research could be used to predict what species are most at risk of extinction.

The work provides evidence that conservation managers can use to support their decision making, creating the best possible outcomes for threatened bird species recovery.

The new report highlights how conservationists can best support the recovery of threatened bird species, as it outlines how different conservation practices may affect hatching rates.

Researchers from the University of Sheffield, Institute of Zoology, and University College London (UCL) looked at 241 bird species across 231 previous studies to examine hatching failure. They found that nearly 17 per cent of bird eggs fail to hatch - almost double the figure reported 40 years ago of just over nine per cent.

Deer carry SARS-CoV-2 variants that are extinct in humans

White-tailed deer
Photo Credit: Heidi-Ann Fourkiller | SFLORG

White-tailed deer ­– the most abundant large mammal in North America – are harboring SARS-CoV-2 variants that once widely circulated but are no longer found in humans.

Whether or not deer could act as long-term reservoirs for these variants that have become obsolete in people is unknown, as scientists need more time and study to verify if it’s true.

The study, “White-tailed Deer (Odocoileus virginianus) May Serve as a Wildlife Reservoir for Nearly Extinct SARS-CoV-2 Variants of Concern,” which published Jan. 31 in the journal Proceedings of the National Academy of Sciences, represents one of the most comprehensive studies to date to assess the prevalence, genetic diversity and evolution of SARS-CoV-2 in white-tailed deer. The study focused on the white-tailed deer population in New York.

“One of the most striking findings of this study was the detection of co-circulation of three variants of concern – alpha, gamma and delta – in this wild animal population,” said Dr. Diego Diel, associate professor in the Department of Population Medicine and Diagnostic Sciences and director of the Virology Laboratory at the College of Veterinary Medicine’s (CVM) Animal Health Diagnostic Center. 

Over the course of the pandemic, deer have become infected with SARS-CoV-2 through ongoing contact with humans, possibly from hunting, wildlife rehabilitations, feeding of wild animals or through wastewater or water sources, though no one knows for sure.

Parasite common in cats causes abortion in bighorn sheep

Bighorn sheep
Photo Credit: David Mark

A parasite believed to be present in more than 40 million people in the United States and often spread by domestic and wild cats could hamper ongoing conservation efforts in bighorn sheep.

A recent study led by Washington State University researchers at the Washington Animal Disease Diagnostic Laboratory found that Toxoplasma gondii, a parasite that infects most species of warm-blooded animals and causes the disease toxoplasmosis, is a cause of abortions, or pregnancy loss, as well as neonatal deaths in the sheep. Researchers documented five cases in bighorn sheep in a study published in the Journal of Wildlife Diseases, but additional studies are needed to determine the full scope of its impact, the authors said.

“We have seen Toxoplasma as a cause of fetal and neonate loss pretty commonly in domestic sheep, but we hadn’t seen pregnancy loss due to toxoplasmosis yet in bighorn sheep,” said Elis Fisk, the lead author of the study. “Unfortunately, it does appear to be causing abortions and some level of death in young bighorn lambs.”

Major Breakthrough as Scientists Sequence the Genomes of Endangered Sharks

Hammerhead Shark
Photo Credit: David Clode

The first-ever chromosome-level genome sequences completed for great hammerhead and shortfin mako sharks have shown that both species have experienced major population declines over a 250,000-year history. Low genetic diversity and signs of inbreeding add a layer of concern to the management of Critically Endangered great hammerhead sharks, whose populations have been in freefall recently due to overfishing for their highly valued fins. In contrast, with a larger effective population size (the ideal breeding population size) in the past and higher genetic diversity, shortfin mako sharks appear equipped to be more resilient to rapid environmental change: that is, if the current fishing pressure on them is substantially reduced.

“With their whole genomes deciphered at high resolution we have a much better window into the evolutionary history of these endangered species,” said Mahmood Shivji, Ph.D., professor at Nova Southeastern University’s (NSU) Halmos College of Arts and Sciences and director of the Save Our Seas Foundation Shark Research Center and NSU’s Guy Harvey Research Institute.

It’s a startling image that describes a milestone in conservation science for sharks. Shivji, Michael Stanhope, Ph.D., from Cornell University’s College of Veterinary Medicine and their collaborators have glanced back in history by sequencing to chromosome level the genomes (entire genetic blueprint) of great hammerhead and shortfin mako sharks. Their DNA timeline shows that their populations have declined substantially over 250,000 years. What the scientists have also found is worrying: great hammerhead sharks have low genetic variation, which makes them less resilient to adapting to our rapidly changing world. The species also shows signs of inbreeding, an issue that can lower the ability of its populations to survive.

Artificial Intelligence in Veterinary Medicine Raises Ethical Challenges

Chimmi (Chimichanga) a few hours before having his spleen removed due to a mass. Detected by Hi-Def Ultrasound by a radiologist. 7/2021
Photo Credit: Heidi-Ann Fourkiller

Use of artificial intelligence (AI) is increasing in the field of veterinary medicine, but veterinary experts caution that the rush to embrace the technology raises some ethical considerations.

“A major difference between veterinary and human medicine is that veterinarians have the ability to euthanize patients – which could be for a variety of medical and financial reasons – so the stakes of diagnoses provided by AI algorithms are very high,” says Eli Cohen, associate clinical professor of radiology at NC State’s College of Veterinary Medicine. “Human AI products have to be validated prior to coming to market, but currently there is no regulatory oversight for veterinary AI products.”

In a review for Veterinary Radiology and Ultrasound, Cohen discusses the ethical and legal questions raised by veterinary AI products currently in use. He also highlights key differences between veterinary AI and AI used by human medical doctors.