Could stem cells be used to treat equine asthma?

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Equine asthma is a common respiratory disease of horses, brought on by repeated exposure to dust and moulds. Although the signs may be improved by medical treatment, this is unlikely to achieve a permanent cure.

 

Doctor Dorothee Bienzle of the Ontario Veterinary College, University of Guelph, has been investigating stem cells as a potential treatment option, working with a group of researchers at the University of Slovenia who have expertise in growing stem cells. The research is published in Stem Cell Research and Therapy.

 

She says, “This is not for the casual investigator because it takes some experience to have the right culture conditions to make sure those cells are clean.  They are not cultured for very long, and when the final preparation is administered to an animal, it must be free of cell culture components that could make inflammation worse.”

 

The study used stem cells derived from subcutaneous fat tissue (“adipose-derived mesenchymal stem cells”: AD-MSC), which were placed directly in the lower airway.

 

Twenty horses with severe equine asthma (SEA) were divided into two groups: ten horses receiving a single application of autologous AD-MSC; and ten given oral dexamethasone daily for three weeks.

 

Horses were assessed before treatment and three weeks later. The research team also monitored the horses for recurrence of SEA over the following year.

 

They found that AD-MSC administration improved the clinical score and decreased the expression of inflammatory markers (such a IL-4, IL-1b) in the broncho-alveolar lavage fluid. 

It took longer for signs of SEA to return in horses treated with stem cells. The researchers noted exacerbations of SEA in the dexamethasone-treated  group shortly after discontinuation of treatment, while most horses in the AD-MSC treated group remained stable for at least 300 days after treatment.

 

They conclude: “In this study, the intrabronchial application of autologous AD-MSC had a modest short-term therapeutic effect and a possible positive long-term effect on SEA.”

 

Speaking about the work in an Equine Guelph webcast* Dr Bienzle added: “Stem cell therapy is a proof of concept at this point. It is not widely available and we don’t want to mislead people ..that this is a commonly available therapy. We’re a long way from that, but horses may get there before humans do.”

 

For more details, see:

 

Effect of intrabronchial administration of autologous adipose-derived mesenchymal 

stem cells on severe equine asthma 

Neža Adamič, Sonja Prpar Mihevc, Rok Blagus, Petra Kramarič, Uroš Krapež, Gregor Majdič, Laurent Viel, Andrew M. Hoffman, Dorothee Bienzle and Modest Vengust

Stem Cell Res Ther. 2022; 13: 23. 

https://doi.org/10.1186/s13287-022-02704-7

 

* https://www.youtube.com/watch?time_continue=703&v=cgWk_VWuwdU&feature=emb_logo

Cloned Przewalski’s horse learning the language of wild horses

 

Kurt, the world's first cloned Przewalski's horse (L)
and Holly (R) at San Diego Zoo  Safari Park
(c) Ken Bohn, San Diego Zoo Wildlife Alliance

A rare Przewalski’s horse, named Kurt, produced by cloning in 2020 is thriving at his home at the San Diego Zoo Safari Park and learning the language of being a wild horse from Holly, a young female of his own species. 

Kurt was cloned from the DNA of a Przewalski's horse that was frozen 42 years ago. It's hoped that once he reaches maturity in a couple of years, he will be able to breed and return lost genetic diversity to his species.

 

By the end of the 1960s, the Przewalski horse, considered to be the last truly wild horse, was extinct in the wild. Some individuals survived in zoos, and an intensive breeding program managed to revive the species, allowing horses to be reintroduced to their natural habitat in the 1990s. 

 

Although there are now over 700 animals roaming the Mongolian steppes, almost all are related to just 12 individuals. This loss of genetic diversity is a cause for concern; maintaining genetic variation is likely to be an important part of ensuring the species’ survival in the future.

 

Kurt was born to a surrogate mother, a domestic quarter horse, which means he had no experience of other Przewalski’s horses. San Diego Zoo Safari Park wildlife care experts embarked on an effort to ensure the young male gained the behavioral language he will need to interact and thrive among his own species.  

 

“Przewalski’s horses normally live in groups where a youngster secures their place in the herd from their mother,” said Kristi Burtis, DM, director of wildlife care, San Diego Zoo Safari Park. “Because Kurt was not born into a herd, he didn’t know the behavioral language that is unique to Przewalski’s horses. Our first step to socialize him was introducing him to Holly.” 

 

Holly arrived at the San Diego Zoo Safari Park in May 2021. Just a few months older than Kurt, Holly was raised in a Przewalski’s horse herd and had the full repertoire of wild horse language to share. Wildlife care specialists at the Safari Park introduced the two, hoping that Holly could serve as a mentor and teacher to Kurt. 

 

After some behavioral sparring, the two have settled into an affectionate pairing. Kurt and Holly have been in a secluded, private habitat since their arrival at the Safari Park and were recently introduced to the Safari Park’s Central Asia field habitat, where they are now viewable by guests. This move will further prepare them to soon join the larger herd of Przewalski’s horses, and the plan is for Kurt to be the breeder stallion when he reaches maturity at 3 to 4 years of age. 

 

“Kurt is significant to his species because he offers the hope of bringing back lost genetic diversity to the population,” said Dr Nadine Lamberski, chief conservation and wildlife health officer, San Diego Zoo Wildlife Alliance. “It is imperative to do everything we can to save this genetic diversity before it disappears.” 

 

By reviving genetic diversity that was stored in San Diego Zoo Wildlife Alliance’s Biodiversity Bank, conservationists hope to expand the strength of the species’ population.

 

For more details, see:

 

https://sandiegozoowildlifealliance.org/pr/kurtandholly

Do younger parents breed faster racehorses?

 Recent research shows that increasing parental age at conception has a detrimental effect on race speed.

 When a split-second can separate the horses at the end of the race, the slightest advantage can give the winner the edge. Research from the university of Exeter found that the speed of thoroughbred horses declines as the age of their parents when they were conceived increases. 

 

Dr Patrick Sharman and colleagues at the Centre for Ecology and Conservation, University of Exeter, analysed 906,027 racing performances of 101,257 horses -   the offspring of 41,107 dams and 2887 sires. The study included data from almost 25 years of racing results, from 1996-2019, involving meetings across Great Britain. The work is published in Royal Society Open Science.

 

Dr Patrick Sharman said “The fact that parental age affects racehorse speed should be of interest to the horseracing industry.  More generally, it adds to an increasing body of evidence which points towards parental ‘state’ at the time of conception having an influence on offspring phenotype. This would have implications well beyond racehorses and the horseracing industry” 

 

They found a ‘significant effect’ of maternal age on speed, with each additional year of age at conception decreasing the offspring speed by 0.017 yards per second.  

 

This may not sound very much, but they suggest it could produce a one second difference in a race over a mile between horses born to a five-year old and a 15-year old mother.

 

Also, they found that the paternal age showed a decrease of 0.011 yards per second for every increasing year in stallion age.

 

Sharman added: “It is perhaps not surprising that offspring speed declines with increasing maternal age. It is the dams, after all, who care for the foal, first in utero, and then through to around 6 months of age. 

 

“What I find fascinating, though, is that increasing paternal age also causes a significant decline in racehorse speed. Thoroughbred stallions play no part whatsoever is raising a foal, so what is behind this decline in speed?” 

 

The authors conclude: “Our analysis identified significant negative within-parent effects of advancing maternal and paternal age on offspring speed. While we had expected to find some evidence of parental age effects, their magnitude is notable, particularly that of the previously undocumented influence of paternal age on offspring speed.” 

 

They hope that their findings will prompt research into the mechanisms by which these parental age influences are transmitted to the offspring.

 

For more details, see:

 

Evidence of maternal and paternal age effects on speed in thoroughbred racehorses

Patrick Sharman, Andrew J. Young, Alastair J. Wilson

Royal Society Open Science Vol 9, no 10 (2022)

https://doi.org/10.1098/rsos.220691

 

Can you help with a senior horse survey?

 If your horse or pony is 15 years or over, the team at the SPILLERS feed company is urging you to spare five minutes to participate in their senior horse survey. The results will help them learn more about the specific needs of older horses and every participant will have the chance to win free feed.

Traditionally, senior horses and ponies were classed as being 15 years or over, but perspectives are changing. Management and care continue to improve, and around 40% of horses and ponies in the UK now sit in this 15+ category. 

 

“If you own or care for a horse or pony who is 15 years or over, we would be very grateful if you could spare five minutes to participate in our survey,” said SPILLERS Product Manager Sarah Nelson. “The results will help us to help more senior horses nutritionally, in the very best ways we can.” 

 

If you would like access to the survey results, just add your email address at the end of the survey. If you submit your email address, you’ll also be added to a prize draw for your chance to win a £50 SPILLERS Feed voucher.

 

The survey is set up with one horse or pony in mind. If you own more than one horse or pony of 15 years or over, they ask you to complete a survey for each horse. Every completion will provide an additional entry into the prize draw.

 

Click here to complete the survey https://www.smartsurvey.co.uk/s/Seniorsurvey/

Free nutrition webinars

For a second year, MARS EQUESTRIAN™ are sponsoring a series of virtual educational webinars covering nutrition
research, nutritional advice, and the latest in laboratory diagnostics and medical imaging. All will be available free of charge. 

Published times, dates and topics are as follows: 

 

• 10AM EDT, October 22, 2022 – Keeping the performance horse healthy and active. “The focus of this first webinar is keeping the performance horse healthy and active. The updates on our core research, diagnostic tools and nutritional recommendations will focus on the specific needs of working horses.”

• 10AM EDT, October 29, 2022 – Keeping the gastrointestinal tract healthy. “The focus of this, the second webinar, is feeding specifically for the gastro-intestinal tract, as well as diagnosing problems and our research behind key nutritional recommendations.”

• 10AM EDT, November 5, 2022 – Keeping the performance horse mobile and active. “The focus of this, the third webinar, is keeping the performance horse mobile and fit. Techniques for measuring fitness, imaging and diagnosing lameness as well as relevant nutritional recommendations will be discussed.”

 

Each webinar session must be registered for individually. For those who are unable to attend the live event, recordings will be available afterwards, as are recordings of last year’s webinars, covering obesity, the senior horse and laminitis.

 

For more information, go to:

 

 https://web.antechdiagnostics.com/equinewebinarseries

Assessing welfare of horses owned by travellers and gypsies

The welfare of Traveller and Gypsy owned horses in UK and Ireland may be better than is sometimes thought, according to a recent study.

 

It has been suggested that horses owned by travellers and gypsies are particularly exposed to reduced welfare, with practices such as fly-grazing, tethering, abandonment of animals and indiscriminate breeding being seen as common. However, there has been little work to investigate the well-being of these animals.

 

Researchers at the Royal (Dick) School of Veterinary Studies, and the Roslin Institute, both at Easter Bush near Edinburgh, Scotland, conducted a study to identify the welfare status of Traveller- and Gypsy- owned horses and to determine the factors that are considered risks to horse welfare in this community. 

 

Marie Rowland and colleagues used a new approach, called ‘Qualitative Behaviour Assessment’ (QBA), to assess the horses’ behaviour and its affective state. A report of the work is published in Animals, as part of a special issue dedicated to equine welfare assessment.

 

They explain that Qualitative Behaviour Assessment is a “scientific approach used to measure the expressive quality of an animal’s behaviour and affective state. It is a ‘whole animal approach’ and is used to measure how the animal is expressing behaviour, often referred to as an animal’s ‘body language’. An animal’s mood or emotional state is communicated through its body language and is assessed using terms that describe their emotional repertoire. This is then applied to interpret an animal’s physical and psychological state.” 

 

The research team assessed horses at different locations throughout the UK and Ireland, including Appleby Horse Fair, (England), and Ballinasloe Horse Fair (Ireland). They also saw horses at British Horse Society (BHS) horse health clinics, and horse owners’ homes and yards.

 

To ensure a standardised procedure was used, all horses were assessed visually from 1.5 metres away.

 

The overall assessment indicated that horse health and welfare was of a good standard, with an optimal body condition score and the absence of skin conditions observed in most horses. Signs of poor hoof care were the most frequently reported welfare problem. Nearly a third of horses showed hoof changes such as hoof wall cracks and defects and long toes.

 

In conclusion, Rowland and colleagues write: ”This study is the first of its type to begin to quantify the welfare of Traveller and Gypsy owned horses. Although further research is required to ensure generalisability to all horses within this population, these results are a good starting point on which to engage with stakeholders who previously identified Traveller and Gypsy owned horses in the UK and Ireland to be particularly vulnerable to poor welfare.”

 

 

For more details, see:

 

The Welfare of Traveller and Gypsy Owned Horses in the UK and Ireland

Marie Rowland, Neil Hudson, Melanie Connor, Cathy Dwyer, and Tamsin Coombs. (2022)

Animals 12, no. 18: 2402. 

https://doi.org/10.3390/ani12182402

Identifying pain behaviours in ridden horses

(c) Anke Van Wake. Dreamstime.com

“Bad” horse behaviour, frequently labelled as “resistant”, “lazy”, or even “explosive”, can be an indicator of pain, according to equine orthopaedics expert Dr Sue Dyson.

Through studies spanning three years, and over 400 horses, Dr. Sue Dyson and colleagues developed The Ridden Horse Pain Ethogram (RHpE), a tool to reliably identify signs of pain before the condition progresses to obvious lameness. 

 A short documentary, featuring Dr Dyson, challenges the way we look at reactive horses, and promotes the notion that a head nod is not the first sign of lameness. 

 “The 24 Behaviors of the Ridden Horse in Pain” follows Dr Dyson and Dr Jim Myers of Gold Coast Equine, as they examine and diagnose show jumper Lauren McMahon’s beloved mare Galina, who was not obviously lame, yet seemed increasingly unhappy under saddle. 

 Lauren had “tried everything” to figure out what was wrong, including ulcer treatments, multiple joint injections and specialized shoeing but Galina only became more resistant under saddle. 

 Galina’s story is not uncommon for horses that do not present with an obvious head bobbing lameness. Oftentimes these are horses that get labelled as “resistant,” “lazy,” and for horses that buck or rear from pain, “explosive.” Trainers often tell riders to “push them through it.” 

 The film shows horse lovers how to spot the early signs of pain while taking viewers on an emotional “ride” through the eyes of a young girl who loves her horse and will stop at nothing to try to figure out how to make her comfortable. 

 The full documentary will be available to watch freely from 30th September 2022. 

 For more details, see: 

 https://youtu.be/nbn0b0W_isQ

Tracking donkey domestication

(c) Demidoff. Dreamstime.com

For thousands of years donkeys have played an important part in human progress. They have 
supplied power for farm work, and provided transport, proving particularly useful in semi-arid and otherwise inaccessible areas.

 To understand the history of the donkey’s domestication, teams at the Centre for Anthropobiology and Genomics of Toulouse (CNRS/ Université Toulouse 3 Paul Sabatier) and scientists from 37 laboratories around the world worked together to build and analyse the most complete panel of genomes ever studied for this animal. 

 

They constructed a comprehensive genome panel containing 207 modern and 31 ancient donkeys, as well as 15 wild equids. 

 

Reporting their findings in the journal Science, the researchers reveal that the donkey was first domesticated in Africa in 7,000 years ago, around the time when the Sahara became the desert region we know today. 

 

They state that it was only 2,500 years later that donkeys left their place of origin in Africa and reached Europe and Asia, where this species developed lineages that, in some cases, still exist today. 

 

“We found a strong phylogeographic structure in modern donkeys that supports a single domestication in Africa ~5000 BCE, followed by further expansions in this continent and Eurasia and ultimately returning to Africa.”

 

By analysing archaeological remains, scientists also uncovered evidence of a previously unknown genetic lineage of donkeys that lived in the Levant, around the eastern Mediterranean, 2,000 years ago. The influence of this lineage is thought to extend far beyond the region, and still today, fragments of its genetic heritage can be found throughout Europe. 

 

The researchers suggest that these discoveries call for new archaeological digs to find the initial source of domestication in Africa, as well as the sequencing of other early donkey genomes on both shores of the Mediterranean sea, to better understand the role of this animal in the history of trade between Europe and North Africa.

 

For more details, see:

 

The genomic history and global expansion of domestic donkeys.

 

Evelyn T. Todd, Laure Tonasso-Calvière, Lorelei Chauvey, Stéphanie Schiavinato, Antoine Fages, Andaine Seguin-Orlando, Pierre Clavel, Naveed Khan, Lucía Perez Pardal, Laura Patterson Rosa, Pablo Librado, Harald Ringbauer, Marta Verdugo, John Southon, Jean-Marc Aury, Aude Perdereau, Emmanuelle Vila, Matilde Marzullo, Ornella Prato, Umberto Tecchiati, Giovanna Bagnasco Gianni, Antonio Tagliacozzo, Vincenzo Tinè, Francesca Alhaique, João Luís Cardoso, Maria João Valente, Miguel Telles Antunes, Laurent Frantz, Beth Shapiro, Daniel G. Bradley, Nicolas Boulbes, Armelle Gardeisen, Liora Kolska Horwitz, Aliye Öztan, Benjamin S. Arbuckle, Vedat Onar, Benoît Clavel, Sébastien Lepetz, Ali Akbar Vahdati, Hossein Davoudi, Azadeh Mohaseb, Marjan Mashkour, Olivier Bouchez, Cécile Donnadieu, Patrick Wincker, Samantha A. Brooks, Albano Beja-Pereira,  Dong-Dong Wu, Ludovic Orlando.

 

Science, (2022). Vol 377, Issue 6611 pp. 1172-1180

 

https://www.science.org/doi/10.1126/science.abo3503

Does exercising foals reduce risk of later fracture?

(c) Rookie72 Dreamstime.com

 Can putting foals on a controlled exercise program reduce the risk of fractures later in life?
Researchers at the University of Illinois at Urbana-Champaign (UIUC) are investigating.

Limb fractures risk ending not only a horse’s career but its life as well.

 

Led by Dr. Annette McCoy and Dr. Mariana Kersh, the research team are looking at the benefits of a carefully controlled exercise program in foals. The study is funded by the Morris Animal Foundation.

 

“We know from another study that mild exercise early in life is associated with positive effects in horses, but exactly how it stimulates bone growth in areas susceptible to fractures is still unknown,” says Dr. Annette McCoy, Associate Professor of Equine Surgery. “Exercise interventions earlier in their lives might better prepare a horse’s bones to face the mechanical forces they will see in their late adolescence and adulthood.”

 

The research draws on information from human medicine, where studies show that children who exercise are less prone to injury as adolescents and adults, and that bone changes are sustained over time. 

 

In an earlier study, Dr. McCoy found that pasture-raised foals in their first year of life are relatively inactive about 85% of the time. The research group wondered whether this low level of voluntary exercise during the period of most rapid growth could contribute to bone injuries when horses are put into work as young adults.

 

The team also knew that too much exercise could have a detrimental effect on foals. Any exercise program should increase activity without over-stressing the foal.

 

The project, being conducted on the University of Illinois Horse Farm, is due to run over two years.  The first six Standardbred foals were enrolled in 2021. A further six foals joined the study this year.

 

When each foal was 8 weeks old, the group performed baseline computed tomography (CT) exams on each foal’s forelimbs to create a three-dimensional picture. The exams measured bone properties, including density and volume. 

 

Foals were then divided into two equal groups. Three foals participated in an 8-week exercise plan, consisting of 1,500 yards of fast trotting in a field once per day, five days per week. The other three foals served as non-exercised controls. 

 

When each foal reached 16 weeks of age, the team performed another CT scan of their limbs to compare differences in bone development. When the foals are about 1 year old, the team will take one final CT scan to see if any changes remain after the conclusion of the program.

 

All the data will be combined into a computer model to help predict the effects of a variety of exercise interventions on bone properties without having to test them in live horses. 

Although horses come in many shapes and sizes, Dr. McCoy hopes the results will help better manage foals of all breeds destined for activities where front leg fractures are common.

 

“Most foals, regardless of breed, spend the first year of their lives sleeping, standing and walking,” said Dr. McCoy. “Because we’re really focused on the pre-training period, I think that our findings should be applicable across breeds.”

 

“One of our goals with this project was to create a computer model that we could use in the future to virtually test exercise interventions in foals,” she said. “What one of our graduate students discovered is that the bones of foals react differently than adult horses to mechanical forces. This meant we couldn’t use the existing adult horse modelling systems for our study – we created something completely new. Nobody had demonstrated this before, and our student won the PhD competition at a recent meeting for this discovery!”

Dr. McCoy hopes to have all their data analyzed by the end of summer 2023.

 

For more details, see:

https://www.morrisanimalfoundation.org/article/horse-exercise-key-to-preventing-leg-fractures

 

Long term horse-owner relationship helps horses cope with change

(c) Photojogtom Dreamstime.com

A new study shows that horses can be more reluctant in new situations if they have multiple riders or have had several owners, or if the horse has been with its current owner for only a short time. 

 The international research team, including scientists from Turku and Helsinki Universities in Finland, and the INRAE of Nouzilly in France, studied interactions between horses and humans as well as how horses react in new situations. The findings are published in Applied Animal Behaviour Science. 

 

Over the millenia horses have been living with humans, they have developed impressive social skills: they are receptive to human emotions and are very good at understanding human demands.

 

"Domestic horses may spend several hours daily in close contact with humans, which can affect horse welfare, physiology, and behaviour” says the lead author of the study, Doctoral Researcher Océane Liehrmann from the Department of Biology at the University of Turku, Finland.

 

“Therefore, it is important to understand which factors can influence the horses' emotions during interactions with humans and what shapes their relationship -- particularly in novel situations that can be very stressful to the animals," 

 

The researchers recruited 76 privately owned leisure horses from the Turku area to perform two behavioural tests, in which they observed and analysed the horses' reactions to novel objects. 

 

In the first test, horses were led to walk on two surfaces that were new to them, a white tarpaulin sheet, and a fluffy blanket. They were led to one of the surfaces by their owner and to the other one by an unfamiliar researcher. 

 

Secondly, the researchers studied whether, when presented with a new object, the horse reacted differently depending on whether they were with a familiar owner or with a stranger. Horses were shown a fluffy stuffed toy by either their owner or an unfamiliar researcher. The horse had one minute in which to freely come and interact with the toy. Then the person approached the horse and tried to touch its neck with the toy.

 

"Interestingly, horses with an exclusive relationship with their owner were the calmest when approaching the novel surfaces and easily agreed to be touched with the toy. Horses that are regularly ridden or trained by different persons showed more stress behaviours in the test situations," Liehrmann says.

 

Similarly, Horses that had spent their whole life with their owner agreed more often to be touched with the new toy than horses that had had several owners during their life. These horses presented more stress behaviours and refused more often to be touched with the toy.

"Horses often have to change ownership, which restricts their ability to make a long-term bond with specific humans. We were particularly interested in studying how the length of the relationship between the horse and the owner affects the horse's behaviour in new, potentially stressful situations," Liehrmann says.

 

The results showed that horses with shorter relationships with their owner were more reluctant in novel situations and presented more stress behaviours when asked to interact with novel objects and surfaces. On the contrary, horses that had at least 6 to 8 years of relationship with their owner, were mostly very calm when introduced to the surfaces or the stuffed toy.

 

Horses older than 17 years old refused more often to step on the tarp or the blanket when they were led by a stranger, while they almost all agreed to do so when they were led by their owner.

 

"Geriatric horses often suffer from poorer eyesight, and it has been shown that they may feel more anxiety towards new situations than younger horses. Therefore, older horses may perceive someone familiar as a secure base, feeling safer to walk over an unknown material when led by a familiar person."

 

The study shows that having a shorter relationship with the owner, multiple handlers and numerous owner-changes can increase the horse's reluctance to novel objects and surfaces and therefore may negatively impact the horse-human interactions in new situations.

 

"Our findings suggest that a positive horse-human relationship may take time to develop as it is shaped by multiple factors, such as the horse's previous interactions with humans. Overall, the results show that animals' relationships with their human caretakers should be better considered in animal welfare and its research," Liehrmann concludes.

 

For more details, see:

 

Multiple handlers, several owner changes and short relationship lengths affect horses’ responses to novel object tests. 

Océane Liehrmann, Alisa Viitanen, Veera Riihonen, Emmi Alander, Sonja E. Koski, Virpi Lummaa, Léa Lansade. 

Applied Animal Behaviour Science, 2022; 254: 105709 

https://doi.org/10.1016/j.applanim.2022.105709

New test for Lyme disease in horses

© Turtleman | Dreamstime.com

A new DNA test developed at Rutgers New Jersey Medical School helped confirm a diagnosis of Lyme disease in a horse. A report is published in the Journal of Veterinary Diagnostic Investigation.

 

Lyme disease (LD) is caused by the corkscrew-shaped bacterium (spirochete) Borrelia burgdorferi. The organism infects white blood cells and cells lining synovial cells, resulting in an inflammatory response. 

 

It is transmitted by ixodes ticks – (typically I ricinus in UK, I scapularis (deer tick) in the north eastern US and Atlantic coast, and I pacificus on the US west coast.) 

 

Many horses in areas where the infection is present carry antibodies without showing signs of disease. Conversely, infected animals may take a long time to produce a detectable antibody response.

  

Signs are generally non-specific. Swollen joints and uveitis (inflammation within the eye) have been reported. Other possible signs include stiffness, lameness, lethargy and behaviour change.

Rare cases may develop neuroborreliosis, in which the bacteria reach the central nervous system, resulting in neurological signs, fever, muscle wasting and difficulty eating.  

 

Clinicians at the Cornell University School of Veterinary Medicine were struggling to diagnose a neurologic case of LD in a sick Swedish Warmblood mare. Although they suspected Lyme disease, standard PCR and antibody tests did not detect the organism. 

 

The new “genomic hybrid capture assay,” a highly sensitive test developed by Steven Schutzer and the team at Rutgers New Jersey Medical School, identified the pathogen in a sample of the horse’s spinal fluid, allowing it to be diagnosed and successfully treated. 

The test works by first selectively isolating DNA from the microorganism causing the disease.

 

“The method is like having a special, specific ‘fishhook’ that only grabs Borrelia DNA and not the DNA of other microbes, nor the DNA of the host (animal or human),” Schutzer said. “Detecting DNA of the disease is a direct test, meaning we know you have active disease if it’s circulating in the blood or spinal fluid.”

 

“The diagnosis of Lyme neuroborreliosis (neurologic Lyme disease) in horses is rarely confirmed antemortem and has frustrated veterinarians for years,” said Thomas Divers, the veterinarian who led the equine team on the paper and who is a professor of medicine and co-chief of the Section of Large Animal Medicine at Cornell University’s College of Veterinary Medicine in New York. “This is a very promising technique. Focused treatment against B. burgdorferi administered in this case resulted in the horse’s complete athletic recovery.”

 

For more details, see: 

 

Genomic hybrid capture assay to detect Borrelia burgdorferi: an application to diagnose neuroborreliosis in horses

Thomas J. Divers, Emmanuel F. Mongodin, Christopher B. Miller, 

Rodney L. Belgrave, Rachel B. Gardner, Claire M. Fraser, Steven E. Schutzer

Journal of Veterinary Diagnostic Investigation (2022). 

https://doi.org/10.1177/10406387221112617

North American horse owners sought for biosecurity study

Even with vaccination and modern medicines, biosecurity plays a crucial role in preventing the spread of infectious disease.

 The Equine Disease Communication Center, with the support of the United States Department of Agriculture, is conducting a study into the awareness and knowledge of biosecurity in the horse industry. Based at the American Association of Equine Practitioners (AAEP) headquarters in Lexington, Kentucky, the EDCC provides real-time and accurate information about diseases, vaccination and biosecurity.

 

They have devised an online survey, which they say will take about ten minutes to complete. The findings will be shared with all parts of the horse industry and used to create educational information and resources to help owners protect their horses. 

 

“Dealing with Covid-19 has highlighted the need for biosecurity procedures to reduce risk of infection; however, most horse owners are still not fully aware of the threat to their horses from both endemic and foreign animal diseases either at home or when traveling,” said Dr. Nathaniel White, EDCC director. “We need to understand the gaps in biosecurity knowledge. Armed with that information, we will create specific plans for facilities and events, enabling the industry to react to domestic and foreign disease threats.”

 

Owners or carers of horses in the USA and Canada are asked to participate in the survey

 

To take part in the survey, go to:

 

https://www.research.net/r/EDCCowner

 

For more about the EDCC, see:

 

https://www.equinediseasecc.org

How well do horses hear electric cars?

38426137(c) Virgonira Dreamstime.com

Electric cars are becoming more common. They make less noise than vehicles with petrol or diesel engines, raising a concern that people may not hear them coming. What about horses? Can they hear electric cars in time? 

A new study instigated by the British Horse Society (BHS) in conjunction with the Electric Vehicle Association (EVA) Scotland. and Robert Gordon University in Aberdeen, Scotland, investigated the reaction of horses to the noise of an electric car.

 

They research team monitored the response of three different horses to approaching cars (three electric and one petrol).

 

A horse, with rider, stood facing along the road with the car approaching from behind. The noise produced by the car was recorded using a high sensitivity microphone. The horse’s reaction to the car was recorded using a smartphone video camera. 

 

They conclude that: “the low-level noises produced by electrical vehicles are being detected by the horses quite early on and they are aware of the presence of the vehicle much before the humans are.”

 

Presenting the report at a launch in Eglington Country Park (Scotland), Alan Hiscox, Director of Safety at The British Horse Society said:

 

“With more and more electric cars on Britain’s roads, this report’s new data and analysis provides significant insight. Not only will it help to alleviate concerns from riders about how their horse reacts to electric vehicles due to limited sound levels, but it will also be a vital tool when it comes to encouraging drivers, regardless of whether they are driving an electronic or conventional vehicle, to be careful when passing horses on the road.” 

 

Professor James Njuguna, Research Strategic Lead at Robert Gordon University, added: “The number of horse and electrical vehicle accidents and incidents are on the rise with society's shift to electric vehicles, bicycles, and scooters. A better understanding of horse behaviour in the presence of an electric vehicle is a step forward for the shared road safety of all road users: drivers, riders, and horses alike. It is a pleasure to support this effort alongside the BHS and EVA Scotland in this campaign. The findings clearly indicate the horse is cautiously recognising EVs long before the rider does and forms a baseline for detailed studies in future.”

 

For more details, see:  

https://www.bhs.org.uk/media/j4vntucq/bhs-horseev-feild-study-report_final-1.pdf

Use of tools by horses

(c) Krueger et al

It used to be thought that using tools was one of the things that set us apart from the animal kingdom. 

However, it is now known that some species use tools. Reports include chimps using sticks to reach food, sea otters using stones to break open shellfish and even elephants deactivating an electric fence by dropping rocks on it.

What about horses? Konstanze Krueger and co-workers conducted an investigation into “unusual” behaviour in horses.

The topic did not lend itself to conventional methods. Instead, they collected reports and video records of unusual behaviour using a dedicated website*. They also searched online for videos showing equids using tools. 

Analysing 635 reports, including 1014 behaviours, they found 20 cases of tool use, 13 of which they termed “unambiguous,” in that it was clear that the behaviour was not trained, caused by reduced welfare, incidental or accidental.

Their findings are published in the journal Animals. 

They report that “the most frequent tool use, with seven examples, was for foraging, for example, equids using sticks to scrape hay into reach. There were four cases of tool use for social purposes, such as horses using brushes to groom others, just one case of tool use for escape, in which a horse threw a halter when it wished to be turned out, and one case of tool use for comfort, in which a horse scratched his abdomen with a stick.”

 

They then assessed the effect of management conditions on tool use and whether the animals used tools alone, or socially, involving other equids or humans. 

They report that management restrictions were associated with tool use in 12 of the 13 cases – such as the use of sticks to scrape hay within reach when feed was restricted. 

“Furthermore, 8 of the 13 cases involved other equids or humans, such as horses using brushes to groom others. The most frequent tool use was for foraging, with seven examples, tool use for social purposes was seen in four cases, and there was just one case of tool use for escape. There was just one case of tool use for comfort, and in this instance, there were no management restrictions.”  

They conclude: “Equids therefore can develop tool use, especially when management conditions are restricted, but it is a rare occurrence.”

For more details, see

Tool Use in Horses. 

K Krueger; L Trager; K Farmer; R Byrne. 

Animals 2022, 12, 1876. 

Possible blood marker for lymphoma?

 Thymidine kinase 1 (TK1) could prove to be a useful biomarker to identify horses with lymphoma, according to recent research.

 Lymphoma is the most common hematopoietic neoplasm (tumour affecting the blood-producing cells) in horses. Lymphomas are less common than sarcoids, squamous cell carcinoma and melanoma, and account for about 2% of all equine neoplasia.

 

Lymphomas can appear in different forms depending on which tissues are involved. Those involving the skin are easier to identify and treat. Tumours involving lymphoid tissue in the chest or abdominal organs are more of a challenge. They tend to produce non-specific signs such as fever, weight loss, colic, ventral oedema, and diarrhoea.

 

Confirmation of a diagnosis relies on identification of malignant lymphoid cells in blood or bone marrow, or in pleural or peritoneal fluid. An accurate serum biomarker would make the task much easier.

 

Thymidine kinase 1 (TK1) plays an important role in DNA replication and cell division. It is only present in cells when they are dividing and is quickly broken down afterwards. Cells dividing normally do not release significant amounts of TK1 into the extracellular body fluids, but cancer cells do.

 

Serum TK1 activity has been used as a biomarker for health screening for malignant diseases and to monitor response to treatment in humans and in dogs.

 

Liya Wang and colleagues at the Swedish University of Agricultural Sciences, Uppsala, Sweden and the University of Bern, and Agroscope, Bern, Switzerland, conducted a study to evaluate the serum level of TK1 as a biomarker for equine lymphoma. 

 

They collected serum samples from healthy and diseased horses, and measured the levels of TK1.

 

They took blood from seven horses with confirmed lymphoma, five horses with suspected lymphoma, 107 control horses with concurrent diseases and 42 healthy horses.

 

They found that “serum TK1 activity was significantly higher in the lymphoma (p <  0.0005), suspected lymphoma (p <  0.02) and tumour-free with concurrent diseases (p <  0.03) groups than in the controls without concurrent diseases, and there was a significant difference between the lymphoma group and the tumour-free group with concurrent diseases (p <  0.0006).” 

 

They conclude: “These results demonstrated that serum TK1 could serve as a useful biomarker to distinguish individuals with lymphoma from control horses with and without concurrent diseases.”

 

For more details, see: 

 

Molecular characterization of equine thymidine kinase 1 and preliminary evaluation of its suitability as a serum biomarker for equine lymphoma. 

Wang, L., Unger, L., Sharif, H. et al.

BMC Mol and Cell Biol (2021). 22, 59. 

https://doi.org/10.1186/s12860-021-00399-x