Effect of stomach acid on probiotics

Probiotics are live microorganisms taken orally that are said to deliver health benefits. Clearly, to have an effect they need to reach the relevant portion of the gut. In horses, this is thought to be the large intestine – the caecum and colon. 

 It is recognised that probiotics may be adversely affected by the acid conditions in the stomach. Some products for human use are presented with enteric protection to help them survive the proximal gastrointestinal tract.

 

A study by Ana Berreta and colleagues at Washington State University, looked at the effect of the equine gastrointestinal tract on equine probiotics. The work is reported in the Journal of Equine Veterinary Science.

 

(c) Sharon Kingston Dreamstime.com

In the laboratory study, they assessed the viability of eleven commercially available equine probiotic products in
conditions of acidity designed to mimic those in the stomach and the small intestine.

 

The research team mixed each of 11 of the probiotics with hydrochloric acid at pH2 (to mimic conditions in the stomach). After 30 minutes the pH was raised to 6.9 and enzymes and electrolytes were added to mimic conditions in the small intestine. Then two hours later they cultured each mixture and used mass spectrometry to identify and quantify the microorganisms present. 

 

The experiment was repeated using an initial pH 4 (to represent the conditions in the stomach when proton pump inhibitors such as omeprazole were being used). 

 

They compared these results with those obtained using probiotics straight from the packet.

 

They found that the gastric pH of 2 adversely affected micro-organisms in six of 11 probiotics. Four of the probiotics had at least one micro-organism that was adversely affected when the pH was increased to 4.0.

 

The microorganism that was most commonly adversely affected by conditions in the virtual gastro-intestinal tract was Enterococcus faecium. In contrast, Saccharomyces cerevisiae (present in one product tested) actually increased significantly in number after exposure to both pH2 and pH4.

 

None of the probiotics tested matched their label claim - all of them contained micro-organisms not listed on the label.

 

The authors conclude that passage through the proximal gastro-intestinal tract may negatively impact the survival of some microorganisms. They suggest that enteric protection should be considered to improve microorganism viability in equine probiotics.

 

For more details, see:

 

Effect of the equine proximal gastrointestinal tract on probiotic viability

A Berreta, JJ Kopper, TL Alexander, CJ Kogan, CR Burbick

Journal of Equine Veterinary Science (2021) 104

https://doi.org/10.1016/j.jevs.2021.103671

New colic researched planned

(c) Maria Itina Dreamstime.com

 Colic features heavily in research projects being supported by the Morris Animal
Foundation in 2022.

New equine health studies to receive funding this year include:

• Studying Intestinal Inflammation

Two research teams will take different approaches to investigate the interaction between inflammation and gut motility, to assist in developing methods of preventing ileus (reduced gut motility) after colic surgery. These approaches could dramatically assist recovery and shorten hospitalization times.

• Understanding Risk Factors for Colic Secondary to Transportation

Researchers will look for colic risk factors associated with transportation, to develop better management recommendations for horses requiring transport.

• Helping Underserved Communities Recognize Early Signs of Colic

Researchers will develop an educational program for horse owners and enthusiasts in underserved communities in Colombia to improve early recognition of colic, a key component of successful treatment.

• New Prognostic Test for Postoperative Complications

Researchers will search for biomarkers to identify horses at higher risk for postoperative surgical complications as a first step toward a new prognostic test.

“Colic consistently ranks among the top health concerns of horse owners and veterinarians,” said Dr. Janet Patterson-Kane, Chief Scientific Officer. “We decided to focus on this topic in this year’s equine call for proposals to advance our understanding of intestinal disease associated with colic and ultimately assist in improving outcomes for horses around the world.”

For more details, see:

https://www.morrisanimalfoundation.org/article/new-equine-colic-studies-2022

Risk of inhaled particles during powered equine dentistry

(c) Chelle 129 Dreamstime.com

Powered equine dentistry places operators at risk of inhaling unsafe levels of inorganic particulate
matter, according to a recent study.

Motorised equipment is regularly used by equine veterinarians and dental technicians when carrying out routine equine dental procedures. Research suggests that particulate matter produced during the process poses possible health risks to the operators through inhalation of aerosolised particles.

 

The study, conducted at Bristol University, investigated the dust particles produced during the motorised rasping of horses’ teeth. Sam Bescoby, in the Langford Vets Equine Department at the University, was lead author in the study, which used cadaver heads that were rasped under standardised conditions.

 

A full report on the work is published in the Equine Veterinary Journal.

 

The authors found that both water-cooled and non-cooled motorised equipment produced particle levels (4.48mg/m³and 7.94 mg/m³ respectively) that were higher than the workplace exposure limit (WEL). (The time-weighted average (TWA) limit set by the Health and Safety Executive in the UK is 4mg/m³)

 

The particles produced were of a range of sizes that could reach all levels of the human respiratory tract. Analysis of the dust found not only calcium and phosphorus from the teeth but also tungsten, aluminium and iron.

 

The researchers found that surgical masks reduced the exposure levels to some extent. However, the FFP3 mask was recommended as more effective than the standard surgical face mask.

 

They advise that a suitable face mask should be worn to reduce exposure to dust particles to within acceptable limits.

 

This study looked at only the inorganic particulate matter. The authors suggest that further work on the biological component of the particulate matter is needed.

 

 

For more details, see: 

 

Quantitative and qualitative analysis of operator inhaled aerosols during routine motorised equine dental treatment.

S.R Bescoby, SA Davis, M Sherriff, AJ Ireland

Equine Vet J (2021) 53, 1036 – 1046

https://doi.org/10.1111/evj.13379

Antibacterial actions of mesenchymal stromal cells

Infected wound healing could be helped by factors secreted by mesenchymal stromal cells. 

Mention “bacteria” and we tend to think of the individual microorganisms that we see growing in laboratory cultures (the so-called “planktonic” forms.) However, in nature it is more common for bacteria to form biofilms – communities of different microbes that become embedded in a slimy extracellular matrix. Biofilms protect the microbes from both antibacterial substances and the immune response of the host.

Biofilms contribute to chronic inflammation and delayed healing of wounds, and are not readily detectable using current routine diagnostic methods. However, biofilm infections should be suspected in equine limb wounds that are not healing as expected. Treatment is based on repeated debridement and application of topical antimicrobial therapy.

 

Mesenchymal stromal cells (MSCs) are cells, isolated from different sites, that can differentiate into other types of cells. They take part in the inflammatory, proliferative, and remodelling phases of tissue repair.

 

Previous work has shown that secretions from MSCs promote wound repair by stimulating fibroblast migration in the skin and promoting development of new blood vessels. They also have antibacterial properties. 

 

A recent study looked at the effect of mesenchymal stromal cells on biofilms.

 

Research by Charlotte Marx and colleagues at the Cornell University College of Veterinary Medicine looked at the effect of mesenchymal stromal cells on biofilms, using an equine skin explant model.

 

They found that secreted factors from equine MSC (collectively referred to as the MSC secretome) significantly decreased the viability of methicillin-resistant Staphylococcus aureus (MRSA) in mature biofilms.

 

They also showed that equine MSCs secrete the cytokine CCL2 that boosts the antimicrobial activity of equine keratinocytes by stimulating the production of cathelicidin and ß-defensin.

 

Reporting their work in the journal Tissue Engineering and Regenerative Medicine, they conclude: “Collectively, these data contribute to our understanding of the MSC secretome's anti-microbial properties, both directly by killing bacteria and indirectly by stimulating immune responses of surrounding resident skin cells, thus further supporting the value of MSC secretome-based treatments for infected wounds.”

 

 

For more details, see:

 

Mesenchymal stromal cell-secreted CCL2 promotes antibacterial defense mechanisms through increased antimicrobial peptide expression in keratinocytes 

Charlotte Marx, Sophia Gardner, Rebecca M. Harman, Bettina Wagner, Gerlinde R. Van de Walle.

Tissue Engineering and Regenerative Medicine (2021) Vol 10 (12) pp1666-1679

https://dx.doi.org/10.1002/sctm.21-0058

What are omics?

Photo: Rossdales Laboratories

 You may have noticed that “-omics” are cropping up with increasing regularity. What are they, and why are they important?

Omics refers to a field of biological sciences including genomics (studying the complete genetic makeup, the DNA, of an organism), transcriptomics (studying RNA), proteomics (proteins) and metabolomics (metabolites). Omics encompasses powerful tools that are rapidly transforming our understanding of disease. 

 

To celebrate how the omics disciplines are making a significant impact on equine veterinary medicine, the Equine Veterinary Journal (EVJ) is giving free access to a Virtual Issue of recent articles covering genomics, transcriptomics, proteomics and metabolomics .

 

The virtual issue has been co-ordinated by EVJ’s Associate Editors Mandy Peffers and Pablo Murcia, with guest editors Carrie Finno, James Anderson and Macarena Sanz.

 

“The relationship between microbiota, health and disease in humans has been investigated for years but similar studies in horses have only been recently published,” says Macarena Sanz, whose editorial navigates five articles on this topic.

 

She concludes: “Although equine microbiomics is in its infancy, new studies will provide an exciting insight into the nature of the equine microbiome and its potential role in the development of disease. Knowledge of the microbiome is key to advancing prophylactic, diagnostic and therapeutic options and to better understanding the pathophysiology of equine conditions.”

 

James Anderson prefaces five papers on advances made in equine medicine within the disciplines of proteomics, metabolomics and lipidomics (a subset of metabolomics). He concludes: “Omics technologies have enhanced our knowledge of the molecular world and provided fascinating insight into the composition and functions of these components across a range of different animal species. Particularly for equine science and medicine they have increased our understanding of molecular changes in disease and informed the development of diagnostic tests. Although still in its infancy within equine veterinary science, this field looks likely to have a significant impact in the coming years.”

 

Mandy Peffers, Associate Editor of the EVJ said: “It is exciting to see how the equine veterinary sector is now keeping pace with human medicine in the omics revolution. As we continue to advance, there will be more tools at our disposal for the diagnosis and treatment of equine disease.”

 

The Virtual Issue is available to all at 

 

https://beva.onlinelibrary.wiley.com/doi/toc/10.1001/(ISSN)2042-3306.OmicsEVJ

Photo competition to promote equine research

 

Keen photographers in North America are invited to enter an online photo contest hosted by Grayson-Jockey Club Research Foundation.

The contest opens February 1, and entries will be accepted until February 28. Entrants are encouraged to submit original photos of horses representing all breeds, backgrounds, and disciplines on Grayson's website.

 

"Our photo contest has proved to be a popular way for horse lovers to spread awareness of the importance of equine veterinary research," said Jamie Haydon, president of Grayson-Jockey Club Research Foundation.

Grayson-Jockey Club Research Foundation has provided more than $30.6 million to fund 397 projects at 45 universities in North America and overseas.

For more details, and to enter the competition, go to:

http://grayson-jockeyclub.org/default.asp?section=2&area=PHOTOINFO

Impact of research on horses' lives

 The next offering in the equine health seminar series from the University of Saskatchewan’s
Western College of Veterinary Medicine on February 8^th is a virtual panel discussion that will explore the benefits of research on horses’ health. 

Topics to be covered include: What's new in horse health research at the WCVM and across Western Canada? What are key horse health problems that researchers are working to solve? If you could choose a health issue that needs further research, what would it be? 

 

The equine health seminar series is open to everyone in the horse community. While there is no cost to attend, you must register in advance.

 

Further details of this, and future seminars, together with recordings of previous talks, are available at:

 

https://wcvm.usask.ca/education/equine-seminars.php#Overview

Monitoring recumbency as equine welfare indicator

 Although horses can doze standing up, they have to lie down to experience deep (rapid eye
movement - REM) sleep, because of the profound muscle relaxation that occurs in REM sleep.   

Normally, horses will spend about 30 minutes a day in REM sleep. They may become sleep deprived if they are unable or unwilling to lie down – for example because of insecurity, or orthopaedic problems. Such horses may lapse into REM sleep while standing and then collapse. 

 

Zsofia Kelemen and co-workers at the University of Veterinary Medicine Vienna conducted a study to investigate the effect of age and orthopaedic problems on the time spent lying down.  A report of the work is published in the journal Animals.

 

A total of eighty-three horses, ages ranging from two to 32 years old, with or without orthopaedic problems, were involved in the study.

 

The research team used wearable automated motion sensors to monitor the time the horses spent lying, moving, and standing. Horses were tracked continuously for 60-hour sessions. Horses with abnormal recumbency patterns were monitored more often and for longer.

 

Eight horses, all with chronic orthopaedic disease, showed signs of REM sleep deficit. They were either seen to collapse, or had abrasions over their knees presumed to be due to falling onto the knees. These horses spent significantly less time lying down.

 

However, in this study, neither age nor lameness due to chronic orthopaedic disease significantly influenced the time spent lying down.

 

The authors conclude that wearable sensor technology can be used to identify horses with low recumbency times at risk for REM sleep deficiency and to assess and monitor equine welfare objectively. 

 

 

For more details, see: 

 

Recumbency as an Equine Welfare Indicator in Geriatric Horses and Horses with Chronic Orthopaedic Disease. 

Kelemen Z, Grimm H, Long M, Auer U, Jenner F. 

Animals. 2021; 11(11):3189. 

https://doi.org/10.3390/ani11113189

Study highlights factors influencing risk of eventing falls

A recent study has identified factors associated with an increased risk of falls during the cross-country phase of eventing, and has suggested modifications that could reduce the risk of injury – making it safer for horse and rider.

Higher-level events, longer courses, more starters in the cross-country phase and less experienced horses and athletes all showed an increased risk.Identifying these risk factors allows riders and event organisers to assess the level of risk for individual horse, rider and event combinations. 

 

The research, published in the Equine Veterinary Journal, recommends simple improvements such as adjusting minimum eligibility requirements (MERs) to ensure horses and riders always compete at a level appropriate to their ability.

 

The study, led by Bristol Veterinary School’s Dr Euan Bennet and Professor Tim Parkin, with Dr Heather Cameron-Whytock of Nottingham Trent University, was funded by Federation Equestre Internationale (FEI).

 

It included data from every horse start worldwide in all International, Championship, Olympics and World Equestrian Games competitions between January 2008 and December 2018. Information from National Federation events was not included. 

 

Of 202,771 horse starts during this period, 187,602 started the cross-country phase. Of these, 1.5 per cent recorded a fallen horse and 3.5 per cent had an unseated rider.

 

At least 50 riders and 109 horses have died since 2000 across all levels of competition worldwide.

 

Bristol Veterinary School’s Dr Euan Bennet said: “Eventing is an exciting equestrian sport, but horses and riders sometimes get injured during competitions. Occasionally they are very seriously injured, even fatally. We have gained a detailed understanding of the risk factors that make horses more likely to fall, so that we can provide actionable advice to governing bodies on how to reduce the number of horse falls, and therefore injuries and fatalities among horses and riders.

 

“This data is about probabilities and we would never say don’t ride because you’re going to have a fall, but we might say what we can see is according to your risk profile you’re in the top 5% at risk of a fall.”

 

The study identified the following factors as contributing to a fall:

 

• Horses competing at higher levels.
• Horses competing over longer cross-country course distances.
• A higher number of starters at the cross-country phase.
• Mares were at increased odds compared with geldings.
• Horses whose previous start was longer than 60 days ago.
• Horses who had previously made fewer starts at the level of their current event.
• At the human athlete level, male athletes were at increased odds of experiencing a fall, compared with female athletes.
• Younger athletes were at increased odds compared with older athletes.
• Less experienced athletes were more likely to fall than their more experienced counterparts.
• Athletes whose previous start was more than 30 days ago were at increased odds compared with athletes who last started within 30 days.
• Athletes who did not finish their previous event, for any reason, were at increased odds compared with those who successfully finished their previous event.
• Horse-athlete combinations who recorded a score in the dressage phase that was higher than 50 (i.e. poor performance) were at increased odds of falling during the cross-country phase compared with combinations who recorded a dressage score of 50 or less.

 

The researchers now hope the FEI will use this new evidence to implement evidence-based rules for eventing which protect the safety of athletes and horses without compromising on competitiveness.

 

 

For more details, see:

 

Fédération Equestre Internationale eventing: Risk factors for horse falls and unseated riders during the cross-country phase (2008-2018)

Euan D. Bennet, Heather Cameron-Whytock, Tim D. H. Parkin

Equine Veterinary Journal (2021) 13522

 

https://doi.org/10.1111/evj.13522

Sustainability in British racing

Concerned about the impact of climate change on equine welfare in the racing industry? Here’s your chance to have a say. 

An online questionnaire, open to anyone involved in racing, has opened to help identify environmental activity, expertise and interest across British racing and breeding.

 

The questionnaire forms part of a wider assessment of progress on environmental sustainability, commissioned last year by industry leaders and initiated and funded by the Racing Foundation.

 

The work aims to build a clearer overall picture of current environmental activities and expertise across racing and breeding. It is hoped that this will identify some of the key issues, risks, and opportunities for British racing, and make recommendations about what steps the industry could take to start embedding environmental sustainability in its long-term planning.

 

In a statement, Brant Dunshea, British Horseracing Authority Chief Regulatory Officer, said: “Climate change and sustainability are major challenges for our sport, given how dependent we are on the environment, transportation, and the use of essential resources.

“There is a real opportunity here for British racing to lead progress in this area, taking positive action to find effective solutions to the challenges we face – and crucially grasp some of the opportunities.

 

Rob Hezel, Chief Executive of the Racing Foundation, said: “A large amount of work has already been carried out across the industry, ranging from decarbonisation efforts to grassland management and waste reduction, so this work will help build an overall picture of where we are and where we want to be.

 

To complete the questionnaire, which runs until 14^th February, go to:

 

https://form.jotform.com/220072452759355

Free online Horse Management Seminar from Rutgers Equine Science Center

Rutgers University Equine Science Center’s annual Horse Management Seminar will be held in a virtual format this year over three Tuesday evenings: February 8th, 15th, and 22nd. Each evening the event will start at 6:30PM (EST) and conclude at 8:30PM (EST) and is free to attend.

 

The first, on February 8th, will cover recent advances in veterinary medicine with an emphasis on equine diseases and rehabilitation and conditioning with Drs. Mark Crisman and Sarah Gold.

 

On February 15th, Drs. Samantha Brooks and Amanda Adams will cover genomics and equine metabolic syndrome.

 

The final evening will feature topics in equine nutrition with Dr. Weinert-Nelson, a recent Rutgers graduate, and Anna Draeger. 

 

For more details, and to reserve your virtual seat, go to :

 

https://go.rutgers.edu/2022HMS.

Behaviour of retrained Thoroughbred racehorses

 

Thoroughbred racehorses have been bred with one purpose in mind – racing. It is often thought that their temperament may result in erratic or dangerous behaviour making them unsuited to other disciplines. 

 

Lillian Hellmann, based at the Equine Genetics and Genomics Group at the University of Sydney, Australia, and colleagues conducted a study to see if such perceptions are justified.

 

The study assessed the behavioural differences, as noted by the owners, between thoroughbred horses bred for racing that entered an alternate discipline after retiring from racing and horses of other breeds. A full report is published in Applied Animal Behaviour Science.

 

The authors analysed data from 313 horses compiled using an online questionnaire. 

Responses were received from a total of 25 countries, with the majority coming from Australia, the United States and the United Kingdom.

 

Horses included in the study were used in four main disciplines: dressage, eventing, show jumping and recreational riding.

 

The analysis revealed few significant differences in behaviour reported by the owners between horses bred for racing and those bred for other pursuits. 

 

Interestingly, and perhaps surprisingly, the researchers reported that where differences did occur, it was generally the thoroughbreds that were thought to behave more favourably. 

 

They report that owners considered Thoroughbreds showed more “dominance / aggression” than horses bred for other disciplines. Despite that, Thoroughbreds were seen as more social and were reported to show higher levels of “self-control.”

 

They suggest that as the average age of a racing thoroughbred is well below that of horses competing in other disciplines, perhaps the dangerous reputation of thoroughbreds is more a reflection of their youth and relative inexperience rather than purely breed predisposition.

 

They conclude: “Although this study does suggest some potential distinctions between the behaviors of thoroughbreds and horses bred for other disciplines, the notion that thoroughbreds may be unsuitable for certain disciplines based solely on their behavior and associated temperament is not supported.”

 

For more detail, see:

 

Owner-perceived behaviour in thoroughbred horses in secondary careers – A pilot study

Lillian Hellmann, Natasha A.Hamilton, Elizabeth A.Staiger, Marina Solé, Brandon D.Velie

Applied Animal Behaviour Science (2021) Vol 244, 105480

 

https://doi.org/10.1016/j.applanim.2021.105480

Brush up on your nutrition and laminitis knowledge with free webinar

Horse owners can take advantage of a series of free nutrition-themed webinars, thanks to SPILLERS™.

The first webinar, to be held on 20th January 2022 at 8pm (GMT), will be hosted by SPILLERS™ nutritionist Gina Burgoyne, and is entitiled “Tips for winter weight gain.” It will cover forage, calories, fibre and oil diets and practical advice.

 

On Thursday 10th February, 8pm, Gina Burgoyne will present a webinar on “Tips for horses prone to gastric ulcers.” The discussion will cover: who is at risk; what to look out for; how nutrition plays a role; and forage.

 

The third webinar, on Thursday 3rd March, 8pm, “Managing your laminitic horse” will be hosted by Isabel Harker and Sarah Nelson. Topics will include: who is at risk; symptoms; how nutrition plays a role; body condition; and grazing tips.

“Whether you have a horse or a pony, and whether you are looking for safe weight gain, weight loss or a maintenance diet these webinars are for you,” said Clare Barfoot RNutr, Marketing and Research and Development Director at Mars Horsecare UK, home of the SPILLERS brand. 

“The webinars incorporate answers to many of the questions we receive via our Care-Line, together with the latest in equine nutrition science, making them highly relevant for every level of horse owner. And the best news is they are free and accessible to all.”

The webinars will be hosted on Microsoft Teams. Each session is free of charge and will last for approximately one hour. 

 

If you would like to join, sign up at:

 

https://www.spillers-feeds.com/webinars

 

 A link to join the webinar will then be emailed to you the day before the session.

Pilot study suggests role for IL-2 in sarcoid treatment.

 Sarcoids are the most common skin tumour in horses. It is estimated that 6-7% of horses in the United Kingdom are affected. 

Currently there is no universally effective treatment for sarcoids and if treatment fails, the sarcoids will often come back worse than they were in the first place. Although the disease is rarely life threatening, many horses with sarcoids are euthanased because the condition is untreatable or because the horse is unsellable. 

 

A study by Johanna Loschelder-Ostrowski and colleagues assessed the use of canarypox expressing feline Interleukin-2 (IL-2) in the treatment of equine sarcoids.

 

Interleukin (IL)-2 is one of the key cytokines (proteins involved in cell signalling). It stimulates cell mediated immunity, activating a range of T-cells. IL-2 is used in human medicine, including for treating cancerous conditions such as metastatic renal cell carcinomas and metastatic melanoma.

 

A canarypox virus vector, which has been genetically modified to contain a gene to make it produce IL-2, was used in the study. (A licenced product is available for use in the treatment of fibrosarcoma in cats.) The canarypox virus does not spread or multiply in cats or other mammals.

 

The technology is widely used in the production of vaccines for horses and other species (such as some equine influenza and West Nile virus vaccines).

 

Firstly, the research team carried out a safety trial in four healthy horses. None of the horses showed significant adverse effects after two treatments.

 

They then assessed its use to treat 20 horses with sarcoids. The sarcoids were injected twice seven days apart, using the recombinant canarypox virus expressing feline IL-2.

 

None of the horses with equine sarcoids showed significant adverse effects after intratumoural treatment.

 

The researchers report that “complete regression was achieved in eight horses (40%) and partial regression in two horses (10%). No change in sarcoid size was observed in two horses (10%) and the disease progressed in five horses (25%). Sarcoids of three horses (15%) showed initial response followed by tumour growth.”

 

However, they noticed a long delay between the first injection and the beginning of tumour remission. “Of the 68% of sarcoids that did show remission after 23 months, remission started after a median time of 30.4 ± 5.4 weeks.” 

 

Reporting their work in the journal Veterinary Dermatology, the authors conclude: “In summary, in this clinical pilot study, the treatment of equine sarcoids with canarypox virus locally expressing IL-2 was easy and safe for both user and horse. Equine sarcoids injected with canarypox virus expressing feline IL-2 showed a reduction in tumour size or a complete remission of the tumour in 50% of cases.”

 

They add: “Further studies are necessary to research vector and feline IL-2 effects in horses, establish an optimal treatment regime for equines and verify the results in a larger population of patients.”

 

For more details, see:

 

Treatment of equine sarcoids using recombinant poxviruses expressing feline interleukin-2

Johanna Loschelder-Ostrowski, Judith Christine Winter, Roswitha Merle, Robert Klopfleisch, Heidrun Gehlen

Veterinary Dermatology (2021)

 

https://doi.org/10.1111/vde.12941

 

Fragile Foal Syndrome not confined to Warmbloods

 Fragile Foal Syndrome (FFS) is a lethal genetic disease of connective tissue which has been reported most frequently
in Warmbloods. However, a recent study has found that the genetic defect responsible is present across a range of other breeds. 

Affected foals are typically aborted during late gestation or born as non-viable foals. If alive at birth, they tend to have problems such as fragile skin, skin defects, hyperextension of the joints and difficulty breathing, and generally require euthanasia within days.

 

FFS has been shown to be an autosomal recessive genetic condition. Carrier animals with one copy of the defective gene (PLOD 1 c.2032 G>A) will be normal, but if mated with another carrier may produce an affected foal.

 

It is now known that the condition is not confined to Warmblood horses.  

 

Research by Katie Martin and colleagues at Etalon diagnostics (a company that offers genetic testing), together with Dr Samantha Brooks at the University of Florida Gainesville and Dr Scott Mclure, of Midwest Equine, Iowa, found that the genetic defect occurs across other horse populations.

 

The team examined samples from 7343 horses from various breeds or type of horse.

The defective gene occurred in 5.32% of Warmblood type horses.  In other affected breeds it was less than 1%. They found no sign of the defect in Arabians, Iberian or Thoroughbreds.

 

Studies of the frequency of the defect in aborted or stillborn foals are lacking, so

the potential economic effect of FFS on the horse breeding industry is not known.

 

The researchers suggest that pre-breeding testing should be used to inform the breeding program – avoiding breeding two carriers, together to reduce the frequency of the FFS gene in the population, and reduce the number of lost pregnancies.

 

 

For more details, see:

 

Fragile Foal Syndrome (PLOD1 c.2032G>A) occurs across diverse horse populations

Katie Martin, Samantha Brooks, Micaela Vierra, W. Tyler Lafayette, Scott McClure, Meredith Carpenter and Christa Lafayette

Animal Genetics (2021) vol 52, p137.

https://doi.org/10.1111/age.13020

Reconstructing prehistory from a teaspoonful of soil

Yukon Photo credit Tyler Murchie

Prehistoric horses survived longer in North America than previously thought, according to a new study.

Researchers at McMaster University, Hamilton, Canada, used DNA capture-enrichment techniques, that they had developed previously, to find ancient DNA from plants and animals in as little as a teaspoonful of soil. The soil for the study was taken from core samples collected from the permafrost at four sites in the Klondike region of central Yukon, in northwest Canada. 

 

The work is published in the journal Nature Communications.

 

Tyler J. Murchie  and co-authors explain that environmental samples, such as soil, contain fragments of genetic material. Most ancient environmental DNA (eDNA) is broken down by bacteria or by physical or chemical processes. However, some of this eDNA becomes bound to sedimentary minerals, which protects it, especially when it is frozen. 

 

By extracting and analysing this sedimentary ancient DNA (sedaDNA), the research team was able to build up a picture of the plant and animal ecosystems from 30,000 to 4000 years ago. 

 

By analysing the DNA, the research team could rebuild the fluctuating animal and plant communities at different time points. Of particular interest was the Pleistocene-Holocene transition, an unstable climatic period 11,000-14,000 years ago when a number of large species such as mammoths, mastodons and sabre-toothed cats disappeared.

The analysis reveals that mammoths and horses were already in steep decline prior to the climatic instability, but they did not immediately disappear due to human overhunting as previously thought. In fact, the DNA evidence shows that both the woolly mammoth and North American horse persisted until as recently as 5,000 years ago.

The authors explain that through the early Holocene (starting about 11,000 years ago), the Yukon environment continued to experience massive change. Formerly rich grasslands - the “Mammoth Steppe”- were overrun with shrubs and mosses, species no longer held in check by large grazing herds of mammoths, horses and bison. Today, grasslands do not prosper in northern North America, in part because there are no megafaunal “ecological engineers” to manage them. 

“The rich data provides a unique window into the population dynamics of megafauna and nuances the discussion around their extinction through more subtle reconstructions of past ecosystems” says evolutionary geneticist Hendrik Poinar, a lead author on the paper and director of the McMaster Ancient DNA Centre.

This work builds on previous research by McMaster scientists who had determined woolly mammoths and the North American horse were likely present in the Yukon approximately 9,700 years ago. Better techniques and further investigation have since refined the earlier analysis and pushed forward the date even closer to contemporary time. 

“Now that we have these technologies, we realize how much life-history information is stored in permafrost,” explains Tyler Murchie, a postdoctoral researcher in McMaster’s Department of Anthropology and a lead author of the study.

“The amount of genetic data in permafrost is quite enormous and really allows for a scale of ecosystem and evolutionary reconstruction that is unparalleled with other methods to date” he says.

“Although mammoths are gone forever, horses are not” says Ross MacPhee of the American Museum of Natural History, another co-author. “The horse that lived in the Yukon 5,000 years ago is directly related to the horse species we have today, Equus caballus. Biologically, this makes the horse a native North American mammal, and it should be treated as such.” 

Scientists also stress the need to gather and archive more permafrost samples, which are at risk of being lost forever as the Arctic warms.

 

For more details, see:

 

Collapse of the mammoth-steppe in central Yukon as revealed by ancient environmental DNA

Tyler J. Murchie, Alistair J. Monteath, Matthew E. Mahony, George S. Long, Scott Cocker, Tara Sadoway, Emil Karpinski, Grant Zazula, Ross D. E. MacPhee, Duane Froese & Hendrik N. Poinar 

Nature Communications (2021) vol 12, Article number: 7120 

 

https://doi.org/10.1038/s41467-021-27439-6

 

For a video presentation, see:

https://player.vimeo.com/video/654303546