Multiple bacteria may be behind elk hoof disease

New research from WSU's College of Veterinary Medicine found that multiple bacteria, rather than a single pathogen, is driving elk hoof disease among Northwestern herds
Photo Credit: Byron Johnson

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Treponeme-associated hoof disease (TAHD) in elk is driven by a polymicrobial community rather than a single pathogen, with Mycoplasma species identified as a critical coinfector alongside the previously known Treponema spirochetes.
• Methodology: Researchers performed a comparative analysis of hoof tissue samples from 129 free-ranging elk across regions with varying disease prevalence, screening for bacterial presence in both lesioned and healthy tissues.
• Key Data: Treponema and Mycoplasma were consistently detected in all diseased samples but were entirely absent in healthy hooves, with no significant statistical difference in bacterial community composition between areas of high versus sporadic disease rates.
• Significance: The confirmation of a complex, multi-bacterial etiology explains the difficulty in managing the disease and suggests that bacterial synergy, rather than a single agent, drives tissue destruction and disease progression.
• Future Application: These findings will facilitate the development of new diagnostic assays capable of detecting TAHD in live animals, moving away from the current reliance on post-mortem tissue analysis.
• Branch of Science: Veterinary Microbiology and Wildlife Epidemiology.
• Additional Detail: Associated bacteria, including Fusobacterium and Corynebacterium, were also linked to lesions, further supporting the conclusion that the disease manifests through a consistent, stable community of microbes regardless of geographic location.

A debilitating hoof disease affecting elk herds across the Pacific Northwest appears to be driven not by a single pathogen but by multiple bacterial species working together, according to a study led by researchers in Washington State University’s College of Veterinary Medicine.

Scientists unlock the genetic key to tackling disease in koalas

Photo Credit: David Clode

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Researchers successfully predicted cancer susceptibility in koalas by analyzing specific inheritance patterns of the Koala Retrovirus (KoRV) within their genomes.
• Methodology: The study integrated whole genome sequencing with detailed life history and health records of over 100 koalas, spanning 46 family groups and four generations, to track viral transmission.
• Specific Mechanism: Bioinformatic analysis distinguished between lethal viral integrations in oncogenes, which caused lineage extinction, and beneficial integrations associated with increased longevity and offspring count.
• Key Statistic: KoRV-associated leukemia remains a critical threat to species survival, accounting for mortality in up to 60% of captive populations and 3% of wild koalas.
• Significance/Application: The derivation of Genetic Risk Scores (GRS) from this data allows conservationists to optimize breeding programs by selecting individuals with low disease risk, thereby improving long-term population health.

Cat Disease Challenges What Scientists Thought About Coronaviruses

Lychee had feline infectious peritonitis, a feline coronavirus. He was part of a clinical trial at the UC Davis School of Veterinary Medicine that cured him of the disease.
Photo Credit: Courtesy of University of California, Davis

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Researchers at UC Davis discovered that the feline coronavirus responsible for Feline Infectious Peritonitis (FIP) infects a much broader range of immune cells than previously believed, including B and T lymphocytes, rather than being limited to a single cell type.
• Methodology: The team examined lymph node samples from cats with naturally occurring FIP, analyzing the presence of viral material and evidence of active viral replication within specific immune cell populations.
• Mechanism: The study confirmed that the virus actively replicates inside these critical immune cells—B lymphocytes (antibody producers) and T lymphocytes (infection fighters)—instead of merely leaving behind inert fragments.
• Key Finding: Traces of the virus were found to persist in immune cells even after antiviral treatment was concluded and the cats appeared clinically healthy, suggesting a mechanism for disease relapse or long-term immune disruption.
• Implication: Because some immune cells have multi-year lifespans, this persistence offers a valuable model for understanding human long COVID and chronic post-viral syndromes, providing a rare opportunity to study viral reservoirs in immune tissues inaccessible in human patients.

Researchers Develop Guidelines for Diagnosing, Monitoring Canine Cognitive Decline

Chimmi (04/09/2010 - 02/23/2025)
Photo Credit: Heidi-Ann Fourkiller

An international working group of canine cognition experts has released a set of guidelines for veterinarians to use in diagnosing and monitoring canine cognitive dysfunction syndrome (CCDS), or canine dementia. The guidelines offer a standard definition of the condition as well as practical diagnostic criteria and are meant to aid both clinicians and researchers in helping senior dogs with cognitive issues.

“We are seeing CCDS diagnoses with increasing frequency, but there isn’t a standardized method for the diagnosis,” says Natasha Olby, Dr. Kady M. Gjessing and Rahna M. Davidson Distinguished Chair in Gerontology at North Carolina State University. “We wanted to propose that standardized method as a starting point that can be built upon over time.” Olby is the leader of the working group and corresponding author of the work.

Canine Ocular Melanosis

Pathophysiology, genomic architecture, clinical progression, and therapeutic management of canine ocular melanosis
Image Credit: Scientific Frontline

In the discipline of veterinary ophthalmology, few conditions present as complex a challenge as Canine Ocular Melanosis (OM). Predominantly affecting the Cairn Terrier, yet not exclusive to this breed. This hereditary disorder is characterized by a relentless, progressive infiltration of pigmented cells within the ocular tissues, leading to severe morbidity through the development of intractable secondary glaucoma. Historically and colloquially referred to as "pigmentary glaucoma," this terminology has largely been abandoned in the academic literature in favor of "ocular melanosis" to more accurately reflect the underlying pathological process: a primary proliferation and migration of melanocytes, rather than a passive dispersion of pigment granules as seen in human pigmentary glaucoma. The disease represents a significant welfare concern due to the chronic pain associated with ocular hypertension and the eventual, often bilateral, loss of vision. Furthermore, its entrenched status within the Cairn Terrier gene pool, driven by an autosomal dominant mode of inheritance and a late age of onset, poses a profound dilemma for breeders and geneticists alike.  

Veterinary Science: In-Depth Description

Image Credit: Scientific Frontline / stock image

Veterinary Science is the branch of medicine and science concerned with the prevention, control, diagnosis, and treatment of diseases, disorders, and injuries in animals. Beyond clinical care, the field encompasses animal rearing, husbandry, breeding, research on nutrition, and product development. Its primary goals are to safeguard animal health, relieve animal suffering, conserve animal resources, promote public health through the control of zoonotic diseases, and advance medical knowledge through comparative medicine.

Escherichia albertii: The still unfolding journey of a misdiagnosed pathogen

Animal to human bacteria pathways
Escherichia albertii is primarily found in mammals and birds, suggesting it is a novel zoonotic pathogen.
Image Credit: Osaka Metropolitan University

Escherichia albertii, initially identified as Hafnia alvei, by the commercial identification biochemical strip, API 20E, was isolated from an infant with diarrhea in Bangladesh in 1989. However, this bacterium was later renamed as a novel species, E. albertii because of its similarities in biochemical and genetic properties to the genus Escherichia, but different from those of any known species in the genus. E. albertii possesses many pathogenic attributes including a key one, which is the ability to produce attaching and effacing (A/E) lesions in the intestinal mucosa mediated by genes on a 35-kb pathogenicity island called the locus of enterocyte effacement. Therefore, it is a member of the family of A/E pathogens.

Novel Kirkovirus May Be Associated with Colitis in Horses

Photo Credit: Nick Page

In a pilot study, researchers from North Carolina State University have found a novel kirkovirus that may be associated with colitis – and potentially small colon impactions – in horses. The study could offer a route to new therapies for horses with colitis symptoms from unknown causes.

“Horses are uniquely susceptible to colitis, and the structure of their gastrointestinal tracts amplify the negative effects,” says Lilly Haywood, Ph.D. student in NC State’s College of Veterinary Medicine. “Horses have very large colons and cecums to facilitate water absorption, so when these structures become inflamed the horses dehydrate quickly. And their large intestines contain a lot of bacteria, so inflammation can lead to those bacteria entering the bloodstream and causing sepsis.” Haywood is first author of the study.

“The other issue when dealing with colitis in horses is that in more than 50% of cases we are unable to find the cause,” says Breanna Sheahan, assistant professor of equine medicine at NC State and corresponding author of the study. “We suspected there might be another viral cause for some of these cases, so we started looking for one.”

Receptors in mammary glands make livestock and humans inviting hosts for avian flu

Microscope-captured images of a mammary gland of a pig show the presence of influenza receptors. In the image on the left, receptors for avian influenza A are colored orange. In the image on the right, receptors for the type of influenza A that typically infects mammals are purple.
Image Credit: Dr. Tyler Harm/Iowa State University

An ongoing outbreak of highly pathogenic avian influenza has affected more than 184 million domestic poultry since 2022 and, since making the leap to dairy cattle in spring 2024, more than 1,000 milking cow herds. 

A new study led by Iowa State University researchers shows that the mammary glands of several other production animals – including pigs, sheep, goats, beef cattle and alpacas – are biologically suitable to harbor avian influenza, due to high levels of sialic acids.

“The main thing we wanted to understand in this study is whether there is potential for transmission among these other domestic mammals and humans, and it looks like there is,” said Rahul Nelli, the study’s lead author and a research assistant professor of veterinary diagnostic and production animal medicine.

Probiotics and Prebiotics Offer Safer Alternatives to Antibiotics in Animal Agriculture

Livestock producers face multiple challenges when adopting probiotics and prebiotics, from selecting effective microbial strains to ensuring product safety, viability, and cost efficiency.
Photo Credit: Joachim Süß

Probiotics, prebiotics, and synbiotics enhance livestock gut health, immunity, and growth while reducing dependence on antibiotics 

A new study by researchers at Shinshu University highlights the essential role of gut microbiota in livestock health and productivity. The researchers show how probiotics, prebiotics, and synbiotics can safely enhance growth and immunity, and balance the growth of intestinal microbes, offering practical alternatives to antibiotics. As global restrictions on antibiotic use intensify, the findings support sustainable livestock management and contribute to reducing antimicrobial resistance risks. 

New stem cell medium creates contracting canine heart muscle cells

Canine iPS cells cultured in a newly developed medium successfully differentiated into functional cardiomyocytes
Image Credit: Osaka Metropolitan University

Scientists obtained stem cells expressing cardiac muscle-specific genes and proteins. The cells displayed regular rhythmic contractions similar to a heart, confirming that they were functional cardiomyocyte cells.

In research, induced pluripotent stem (iPS) cells are derived from skin, urine, or blood samples and developed into other cells, like heart tissue, that researchers want to study. Because of the similarities between certain dog and human diseases, canine iPS cells have potential uses in regenerative medicine and drug discovery. 

New test can flag drugs that could be harmful to cats

Shelby
Photo Credit: Heidi-Ann Fourkiller

A new test developed at Washington State University will help pharmaceutical companies, veterinarians and regulatory agencies identify drugs that may trigger severe — but preventable — neurological side effects in some cats.

Even in healthy cats, many commonly prescribed drugs can cause dangerous reactions when administered in specific combinations or when given to felines born with a mutation in their MDR1 gene. This mutation disrupts a protein called P-glycoprotein, which normally helps remove harmful substances from the brain and body, putting affected cats at risk for serious reactions from drugs that are perfectly safe for most cats.

Developed by WSU veterinary pharmacologist Dr. Katrina Mealey and laboratory supervisor Neal Burke, the test can determine if a drug relies on P-glycoprotein to be safely processed. Using the test, Mealey and Burke identified 10 new drugs that pose a risk to affected cats. The findings were detailed in the journal Frontiers in Veterinary Science. The method is available as a fee-for-service through WSU, or companies and governing agencies can use the published procedure to run their own screenings.

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

Scientific Frontline: Extended "At a Glance" Summary: Elephant Deaths Linked to Bisgaard Taxon 45

The Core Concept: Scientists have discovered that a little-known bacterium, provisionally named Bisgaard taxon 45, caused the fatal septicemic infections responsible for the mysterious deaths of endangered African savanna elephants.

Key Distinction/Mechanism: Unlike initially suspected causes such as anthrax, cyanide poisoning, or poaching, the mortalities were definitively traced to an unclassified member of the Pasteurella bacterial family. This marks the first time this specific pathogen has been associated with elephant deaths, and researchers believe the infection is exacerbated by physiological stress from extreme weather events (like severe drought) and transmitted through the highly sociable behavior of the herds.

Origin/History: The investigation focused on the sudden deaths of thirty-five elephants in a 40-by-25-kilometer radius of northwestern Zimbabwe between August and September 2020. This incident closely followed a massive die-off of approximately 350 elephants in neighboring Botswana from May to June 2020.

Major Frameworks/Components:

• Postmortem examinations and field sampling of wildlife carcasses.
• Toxicological analyses to effectively rule out anthropogenic poisons, including cyanide.
• Bacterial isolation and genetic analysis to classify the unknown pathogen.
• Epidemiological assessment of the link between environmental stress factors, animal sociability, and disease transmission.

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.”