AI camera system could give breeders early warning of foaling

  

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For most mares, foaling is a straightforward process that ends with the arrival of a healthy foal. However, when
complications occur, they can escalate rapidly. Problems such as an abnormal foetal presentation can quickly become life-threatening for both mare and foal, making rapid veterinary intervention essential. Having experienced staff on hand at the right moment can mean the difference between a successful birth and a tragic outcome.

 

The challenge is knowing exactly when that moment will arrive. Mares often show remarkably few obvious signs that foaling is imminent, forcing stud farms to maintain overnight watches throughout the breeding season. On large commercial studs, this means dedicated staff monitoring mares around the clock, while owners with just one or two mares frequently endure several sleepless nights waiting for labour to begin.

 

A reliable system capable of predicting foaling before labour starts would therefore be invaluable, improving welfare while reducing both labour demands and the risk of missing a difficult birth.

 

Researchers from the School of Veterinary Medicine at Kitasato University in Japan, working with engineers from Noritsu Precision Co., Ltd., have now tested a fully non-contact monitoring system that combines thermal imaging with artificial intelligence to predict the onset of foaling under commercial breeding conditions.

 

The study involved 115 pregnant Thoroughbred mares on 13 breeding farms in Hokkaido during the 2024 foaling season. Each mare was housed individually in a foaling box overnight between 3 p.m. and 7 a.m. and turned out during the day. A camera unit, combining a thermal infrared camera with a conventional visible-light camera, was mounted on the stall wall so the mare always remained within view.

 

Unlike wearable sensors or invasive monitoring systems, the camera required no contact with the mare. Instead, artificial intelligence analysed images every five minutes, measuring locomotor activity and body surface temperature from the thermal images while simultaneously identifying posture changes and tail-raising behaviour from the visible-light footage.

 

The researchers discovered that mares exhibit two distinct phases before giving birth. The earliest indicators appeared around 70 to 90 minutes before foaling, when both movement and body surface temperature relative to the surrounding environment increased significantly. More obvious behavioural changes, including frequent posture adjustments and repeated tail raising, occurred much closer to delivery, typically within the final 25 to 45 minutes 

These sequential changes allowed the researchers to develop a prediction model that reflected the natural progression towards labour. Using only the early indicators of movement and temperature, the system correctly detected impending foaling in 80% of mares, providing an average warning time of just over three hours 

 

When the later behavioural signs were incorporated into the model, predictive accuracy increased dramatically. The complete system correctly predicted foaling in 94.8% of mares, with an average alert approximately 89 minutes before delivery, providing staff with sufficient time to prepare for the birth or summon veterinary assistance if necessary.

 

The findings suggest that combining thermal imaging with AI-based behavioural analysis could offer breeders a practical, reliable and welfare-friendly method of monitoring mares during the foaling season. Because the system operates entirely without physical contact, it avoids the limitations of wearable devices while remaining suitable for routine use on commercial breeding farms.

 

While further studies will be needed to evaluate its performance in different breeds and management systems, the technology represents a promising step towards smarter foaling surveillance. For breeders, earlier warning of impending birth could reduce overnight monitoring, improve staff efficiency and, most importantly, increase the chances of providing timely assistance when mare and foal need it most.

  

For more details, see:

 

Nabenishi, Hisashi, Nagisa Taki, Shoji Nishibayashi, and Tomoyuki Ishii.

Noninvasive Two-Phase Foaling Prediction in Thoroughbred Mares Using Thermal Imaging and AI-Based Behavioral Analysis

Animals (2026) 16, no. 14: 2221.

https://doi.org/10.3390/ani16142221

Shire Horse Society launches genetic study to safeguard the breed’s future

  

The Shire Horse Society is set to embark on a major scientific project in 2026 aimed at helping
secure the future of one of Britain’s most iconic native horse breeds.

Originating in England, particularly across the Midlands and Fenland regions, the Shire horse is renowned as a powerful draught breed with a history stretching back to the great horses of medieval England. Following the decline of heavy cavalry, Shires became indispensable to British agriculture and industry, ploughing heavy clay soils and hauling wagons, barges and brewery drays. The breed became a cornerstone of the Industrial Revolution, serving farms, mills and breweries throughout the country.

Today, however, the breed faces significant challenges. The Shire horse is currently classified as “At Risk” by the Rare Breeds Survival Trust, with official UK figures indicating a breeding population of fewer than 1,000 mares.

To help protect the breed’s future, the Shire Horse Society will work with genetics specialists at Nottingham Trent University’s Medical Technologies Innovation Facility (MTIF) to undertake a comprehensive genomic analysis of the UK Shire horse population. The project will be led by Dr Adam Varney, Senior Research Fellow at MTIF, alongside Dr Andy Dell, who has already worked closely with the Society on genetic management initiatives.

The study aims to provide a detailed understanding of the breed’s genetic makeup and evaluate the effectiveness of current pedigree-based breeding programmes. By examining the breed at a genomic level, researchers hope to identify both current and potential future genetic issues, enabling breeders to make more informed decisions and helping to ensure that future generations of Shires remain healthy, diverse and fit for purpose.

The Society has already adopted the SPARKS (Single Population and Records Keeping System) breeding support programme, which helps manage genetic diversity and reduce the risk of inbreeding. SPARKS calculates the relatedness of horses within the stud book and provides guidance on suitable mare and stallion pairings. While the system has proven valuable, genomic analysis offers a far more detailed picture of genetic diversity and health.

Managing inbreeding is particularly important in rare breeds, as loss of genetic diversity can lead to increased infertility, higher foal mortality, a greater risk of inherited disorders and reduced disease resistance. By combining pedigree information with modern genomic science, the Society hopes to strengthen long-term breeding strategies.

Similar genomic projects have already been successfully completed by the Eriskay Pony Society and the Cleveland Bay Horse Society, while the Suffolk Horse Society has recently begun its own programme.

Funded entirely through a generous legacy donation, the project is open to all owners of pure-bred Shire horses registered in the UK Shire Horse Society Stud Book. Mares, stallions and geldings of all ages are eligible to participate.

Collecting samples will be straightforward, requiring only a small hair sample. Testing kits, together with instructions, will be distributed directly to owners, who can either collect the samples themselves or ask their veterinarian to assist. Samples must be returned to the Society by 30 August 2026.

Once received, the DNA will be extracted and analysed by the NTU research team. Importantly, while samples identify individual horses during collection, all data will be anonymised before analysis. The project is designed to assess the breed as a whole, rather than individual animals.

The Shire Horse Society hopes that widespread participation will provide the most complete genetic picture possible. The findings are expected to play a vital role in shaping future breeding plans and ensuring that this historic British breed can thrive for generations to come.

IVF progress

  

Researchers from the University of Florida Department of Animal Sciences have reported
progress in equine reproduction, demonstrating that frozen-thawed stallion sperm may be more effective for in vitro fertilisation (IVF) than fresh or chilled semen. The findings, published in the journal Reproductive Biology, could have significant implications for the performance horse industry.

In horse breeding, IVF has historically lagged behind its success in other species such as cattle. One major challenge has been the difficulty of achieving proper sperm function outside the body. In particular, stallion sperm require a process known as capacitation before they can penetrate and fertilise an egg. This involves a series of physical and biochemical changes that are highly sensitive to environmental conditions such as temperature and time.

The need for improved IVF techniques is especially relevant in the performance horse sector. Highly valuable mares are often selected for breeding, but not all are able to safely conceive or carry a pregnancy. Certain conditions, including uterine disease, prior foaling injuries, or lameness, may increase the risk associated with pregnancy. Additionally, some mares may be performing at their optimal level and cannot be withdrawn from competition for breeding purposes.

In such cases, producing an embryo via IVF and transferring it into a surrogate mare offers a safer alternative, protecting both the donor mare and the developing foal.

To better understand how to achieve successful fertilisation, the research team investigated how different types of semen - fresh, chilled, and frozen-thawed - respond under capacitating conditions. They also compared various sperm selection methods, including Percoll gradients, Swim-Up techniques, and microfluidic systems*. These approaches were assessed based on key indicators such as sperm motility, acrosome integrity, and biochemical markers like tyrosine phosphorylation.

The results revealed that temperature played a critical role. Incubating sperm at body temperature (38°C) reduced motility, whereas maintaining sperm at ambient temperature allowed optimal capacitation within approximately four hours. At this time point, sperm also showed the highest level of acrosome integrity, an important factor for successful fertilisation.

The research team found that frozen-thawed sperm performed better than fresh or chilled samples in the IVF setting. Although freezing and thawing can place mild stress on sperm cells, this stress appears to trigger changes that promote capacitation. As a result, frozen sperm were able to function effectively with fewer preparatory steps.

Further experiments confirmed fertilisation success through the observation of pro-nuclear formation and early embryo development. Notably, microfluidic sperm selection produced superior results compared to traditional Swim-Up methods, improving sperm quality and fertilisation potential.

Beyond the biological findings, the use of frozen sperm offers practical advantages. Unlike chilled semen, which must be used within a short timeframe, frozen semen can be stored indefinitely and thawed when needed. This flexibility allows veterinarians and breeders to better coordinate the timing of egg collection and fertilisation, making the IVF process more efficient and accessible.

This research represents a significant step forward after more than three decades of limited progress in equine IVF. By identifying conditions that support effective capacitation and demonstrating the advantages of frozen sperm, the study provides a foundation for improving embryo production in horses. For the equine industry, these advances could expand breeding options while prioritising the health and welfare of valuable mares.

 

For more details, see:

Joao D. de Agostini Losano, Jillian E. Guertin, Maura S. McGraw, Lana Katz, Vilceu Bordignon, Justin W. Callaham, Jose H.F. Pontes, Perla Fleury, Marc Maserati, Carly Turner, Bradford W. Daigneault,

Temporal characterization of conditions that promote functional capacitation of stallion sperm,

Reproductive Biology (2026) Vol 26, 2,101201,

https://doi.org/10.1016/j.repbio.2026.101201

 

 

*Percoll gradient centrifugation is a method that separates sperm based on their density. A liquid medium is layered in tubes at different concentrations, and the semen sample is placed on top. When the tube is spun in a centrifuge, sperm cells move through the layers depending on their density and quality. The most viable sperm - those that are motile and structurally normal - tend to settle into a specific layer, while debris, dead sperm, and less functional cells remain elsewhere. This method is widely used because it produces a relatively clean and concentrated sample of high-quality sperm.

Swim-Up technique relies on sperm motility rather than density. In this approach, a semen sample is placed at the bottom of a tube with a layer of culture medium above it. Over time, the most motile sperm actively swim upward into the medium. These sperm are then collected from the top layer. This technique mimics a natural selection process, as only the strongest swimmers are chosen. However, it can result in lower sperm numbers and may not always select for the best overall sperm quality, especially if motility is reduced.

Microfluidic sperm selection systems represent a more modern and precise approach. These systems, such as microfluidic sperm selection, use tiny channels that mimic aspects of the female reproductive tract. Sperm are introduced into a device where they must navigate through narrow pathways and fluid flows. Only sperm with good motility, proper morphology, and functional membranes can successfully pass through the system. This method reduces mechanical stress on the sperm compared to centrifugation and may better preserve their physiological state.

Study shows “Bute” can temporarily disrupt assisted breeding in horses

(c) Zuzana Tillerová Dreamstime.com

 Research from Texas A&M University has found that phenylbutazone (“bute”), one of the most
commonly used pain-relief medications in horses, can interfere with artificial breeding techniques, especially at the crucial stages of egg maturation, fertilisation, and early embryo development.

This finding is particularly important for mares involved in assisted reproductive technologies (ART), such as intracytoplasmic sperm injection (ICSI) or embryo transfer. Many donor mares, especially older mares retired from competition or horses working through chronic lameness, may be receiving long-term bute to manage pain. 

Phenylbutazone is a non-steroidal anti-inflammatory drug (NSAID) widely used to manage lameness. While highly effective for pain, the Texas A&M team discovered that it can temporarily reduce the ability of a mare’s egg cells (oocytes) to develop properly in laboratory conditions.

In horses, assisted reproduction is more difficult than in humans. Mature oocytes must be collected, cultured for around 30 hours, and then fertilised by injecting an individual sperm directly into the egg, a process known as ICSI. If the egg fails to mature or the early embryo fails to grow, it cannot be used.

The research team tested the effect of a 10-day course of oral bute on oocyte quality. Oocytes were collected using transvaginal ultrasound-guided aspiration and evaluated shortly after treatment, then again one month and two-and-a-half months later. Cumulus–oocyte complexes (COCs), the small clusters of egg cells and surrounding support cells, were matured in vitro and fertilised using ICSI.

Key findings included:

Immediately after treatment (3 days post-bute):

• Oocytes from treated mares were less likely to be recovered and mature normally.
• Cleavage (early embryo division) rates were significantly lower.
• No fertilised oocytes from bute-treated mares developed into blastocysts, whereas 28% of those from untreated mares did.

Later in recovery (33 and 77 days post-treatment):

• Differences between groups disappeared.
• Oocytes collected after these intervals matured and developed at normal rates.

This means that bute’s negative effect on reproduction is real but temporary. A waiting period of at least one month after stopping bute appears to allow oocyte quality to return to normal.

This study suggests that:

• Egg collections performed shortly after a course of bute may fail, wasting both time and significant financial investment.
• Planning ART procedures around medication withdrawal could improve success rates.
• A minimum 30-day washout period may be advisable before oocyte aspiration.

Future research will explore whether other NSAIDs offer safer alternatives that do not interfere with reproduction.

For more details, see:

Luisa Ramírez-Agámez, Camilo Hernández-Avilés, Canaan M. Whitfield-Cargile, Michelle C. Coleman, Charles C. Love,

Treatment of mares with the non-steroidal anti-inflammatory drug (NSAID) phenylbutazone transiently affects in vitro maturation of equine oocytes and blastocyst development after Intracytoplasmic Sperm Injection (ICSI),

Theriogenology (2024), Vol 223, Pp 53-58

https://doi.org/10.1016/j.theriogenology.2024.04.017

Early-life management linked to racing success in Thoroughbreds, RVC study finds

(c) Tania Penderakis Dreamstime.com

Recent research conducted by the Royal Veterinary College (RVC) has shown that
Thoroughbred foals given extensive turnout in larger pastures during their first six months of life, and those weaned at an older age, are more likely to enter training, race more frequently, and earn greater prize money later in life.

The study provides new insight into how gestational and early-life management can influence the growth, development, and long-term athletic performance of racehorses. It aimed to enhance understanding of how early-life health and husbandry practices affect both racing outcomes and the financial sustainability of Thoroughbred breeding enterprises.

According to the research team, this is the first UK-based field study to comprehensively evaluate the effects of early-life exposures, particularly exercise and turnout, on later-life milestones and race performance in Thoroughbreds. The findings offer direct practical applications for stud farms, supporting both horse welfare and industry retention, in line with the Horse Welfare Board’s strategy for improving the welfare of racehorses.

The research, led by Dr Rebecca Mouncey, Post-Doctoral Research Fellow at the RVC, was conducted as a prospective cohort study. The team followed 129 flat-race bred Thoroughbred foals, born in 2019 and 2020 on six stud farms across the UK, from birth through to training and early racing careers.

Detailed data were collected on each dam’s reproductive history and health during pregnancy, alongside daily records of foal management, health status, turnout duration and area, and any veterinary-attended illnesses or injuries. These records were maintained until the foals left their stud farms or exited the study. Racing performance data were subsequently collated from industry databases up to the horses’ fourth year of life.

Statistical analyses, including mixed-effects logistic and linear regression models (with farm, mare, and stallion as random effects), were used to examine associations between gestational and early-life exposures and later racing performance.

Of the 129 horses studied, 76% (98/129) went on to race by the age of four, with a median of seven starts (interquartile range [IQR] 4–11) and median prize earnings of £6,898 (IQR £1,712–£17,987).

Significant associations were identified between early-life management factors and later performance:

• Turnout: Foals that spent more time turned out at pasture during their first six months of life were more likely to race and earned more prize money.
• Increasing average daily turnout time and pasture size were associated with higher odds of racing (Odds Ratio 1.31, 95% CI: 1.09–1.58, p = 0.004) and increased total prize earnings (β = 0.32 lnGBP, 95% CI: 0.03–0.61, p = 0.03).

• Weaning Age: Foals weaned later were more likely to race and made a greater number of race starts.
• Each additional day of age at weaning increased both the odds of racing (OR 1.03, 95% CI: 1.01–1.05, p < 0.05) and total number of runs (β = 0.09, 95% CI: 0.04–0.14, p < 0.05).

These results indicate that management during the first six months of life plays a critical role in preparing Thoroughbreds for future athletic success.

The findings demonstrate that early-life turnout and weaning practices significantly affect race participation, performance, and financial outcomes. Providing foals with ample turnout opportunities and delaying weaning until after this key developmental window may support positive musculoskeletal adaptation and improved future performance.

Dr Mouncey noted that: “This study is the first of its kind to evaluate the impact of early-life experiences on later racing performance in Thoroughbreds. Our findings highlight that the first six months of life represent a crucial developmental period in which management practices must promote optimal tissue development and welfare.”

The study was funded by the Horserace Betting Levy Board, the Racing Foundation, and the RVC’s Mellon Fund for Equine Research, and is published in the Equine Veterinary Journal.

For more details, see:

Mouncey R,  de Mestre AM,  Arango-Sabogal JC,  Verheyen KL.  

Born to run? Associations between gestational and early-life exposures and later-life performance outcomes in Thoroughbreds. 

Equine Vet J. (2025).

 https://doi.org/10.1111/evj.70084

Help Advance Neonatal Foal Care – Share Your Experience with the Madigan Squeeze Technique

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 Have you used the Madigan Squeeze Technique on neonatal foals? Dr. Monica Aleman and Dr John Madigan of UC Davis are inviting veterinarians, breeders, farm managers, and horse owners to share their experiences as part of a vital study aimed at improving outcomes for foals with Neonatal Maladjustment Syndrome (“dummy foal”).

Neonatal Maladjustment Syndrome (NMS) is a condition seen in newborn foals that affects their behaviour and awareness. Foals with NMS may not recognise or bond with their mother, may not suckle normally, and can seem disoriented. More seriously affected foals may develop seizures. NMS was once thought to be caused by lack of oxygen during birth, but recent research suggests it may also be linked to high levels of calming hormones (neurosteroids) that usually decrease after birth but sometimes remain too high.

 

The Madigan Squeeze Technique, developed by Dr. Madigan, involves applying steady pressure using soft ropes wrapped in 3–4 loops around the foal’s chest and rib cage for approximately 20 minutes. This mimics the natural birth process and is believed to reduce neurosteroid levels that keep foals in a subdued, sleep-like state in utero. The foal typically lies down and enters a calm, trance-like state, then awakens more alert—often with improved responsiveness.

 

Drs. Aleman and Madigan are collecting real-world data on the technique’s effectiveness and application. Whether you’ve experienced remarkable recoveries, faced challenges, or simply observed how the technique worked, your insights are essential.

 

“Your experiences - whether as a veterinarian, breeder, farm manager, or horse owner - are invaluable in helping us assess how widely the technique is used and how effective it has been,” they note.

 

By contributing, you'll help shape a forthcoming report on neonatal foal care that will be shared with the broader equine community - advancing research and potentially improving foal survival rates worldwide.

 

 

Take the survey here:

 

 https://www.surveymonkey.com/r/M3J2P32 

Updated HBLB Codes of practice now available

The Horserace Betting Levy Board (HBLB) Codes of Practice, first introduced in 1977, were developed in response to the growing threat of Contagious Equine Metritis (CEM) and the lack of standardised biosecurity measures in the equine industry. CEM outbreaks were causing significant reproductive issues in mares and financial losses for breeders. The introduction of the Codes aimed to establish uniform disease prevention and control protocols, helping to safeguard equine health and protect the breeding industry.

The HBLB Codes of Practice outline voluntary, yet highly recommended, guidelines designed to assist breeders and their veterinary surgeons in the prevention, management, and control of specific infectious diseases in all breeds of horses and ponies.

While the Codes were originally intended for breeding enterprises and stud farms, their value extends beyond this sector. They have become a comprehensive resource on infectious disease control, biosecurity, and equine health management, making them relevant to:

• Horse owners aiming to prevent disease outbreaks in their yards.
• Riders and trainers seeking to maintain healthy horses and implement sound biosecurity practices.
• Veterinarians using the Codes as a reference for best practices in disease diagnosis, treatment, and prevention.

Since their introduction, the HBLB Codes of Practice have been regularly updated and expanded to include recommendations for controlling other significant equine diseases, such as:

• Equine Herpesvirus (EHV) – which can cause respiratory disease, abortion, and neurological symptoms.
• Equine Influenza (EI) – a highly contagious respiratory infection that can spread rapidly.
• Strangles – a bacterial infection caused by Streptococcus equi, known for its painful abscesses and potential complications.
• Equine Viral Arteritis (EVA) and Equine Infectious Anaemia (EIA) – both serious infectious diseases that threaten equine health.

As a result, the Codes have evolved into an essential reference not only for breeding establishments but also for all equine professionals, owners, and riders, offering a wealth of practical information on biosecurity, vaccination, and disease management. They are an invaluable resource for anyone involved in equine care and management, providing evidence-based guidance on reducing the risk of infectious disease outbreaks and promoting the overall health and welfare of horses.

 

The HBLB Codes of Practice are freely available online and can be accessed at:

https://codes.hblb.org.uk

 

Discovery links genes to performance-limiting disease in Thoroughbred racehorses

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 New research has identified specific genetic markers linked to Recurrent Laryngeal Neuropathy (RLN), a disease that significantly impacts the performance of Thoroughbred racehorses. This discovery, hailed as a major step forward in combating this debilitating condition, paves the way for the development of a genetic test to identify horses with a threefold increased risk of developing RLN. 

Often referred to as laryngeal hemiplegia or "roaring," RLN is an upper respiratory tract (URT) disorder that affects up to 18% of Thoroughbred horses. The condition is characterised by the progressive degeneration of the recurrent laryngeal nerve, which controls the muscles that open the horse’s airway. As the disease progresses, airflow during exercise becomes restricted, leading to laboured breathing, reduced oxygen intake, and impaired athletic performance.

 

RLN represents a significant challenge for the Thoroughbred racing industry due to its economic and competitive implications. While pre-purchase examinations, including upper respiratory endoscopy ("scoping"), can detect RLN, resting evaluations in young horses often fail to identify the disease or predict its future onset.

 

To tackle these challenges, researchers at University College Dublin, in collaboration with Equinome and a world-class Thoroughbred training facility, conducted an extensive study funded by Research Ireland. The research team employed state-of-the-art diagnostic methods, including resting and overground exercising endoscopy of the upper airway, as well as laryngeal ultrasonography. This rigorous approach ensured accurate phenotyping of horses as either RLN cases or controls.

 

The study analysed over 200 Thoroughbred horses in training, utilizing both clinical evaluations and genetic testing. The case-cohort group was supplemented with detailed questionnaires to capture additional phenotypic data. A full report of the research is published in the Equine Veterinary Journal.

 

Using advanced DNA technologies, researchers conducted a genome-wide association study (GWAS) to identify genetic variants associated with RLN. They genotyped 43,831 single-nucleotide polymorphisms (SNPs) from 235 horses (110 RLN cases and 125 controls) and estimated the heritability of the trait. The findings revealed a set of genetic markers that significantly contribute to RLN risk, independent of other factors such as height.

 

This discovery is particularly important because it confirms a genetic predisposition to RLN and identifies specific markers that could be used to predict the disease in Thoroughbreds.

This research marks a significant advance in equine genetics and respiratory health, offering new hope for addressing RLN, a disease that has long plagued the Thoroughbred racing industry. The ability to identify horses with a higher genetic risk for RLN has far-reaching implications for the Thoroughbred racing industry. 

 

The next step will involve translating these findings into a practical genetic test that can be readily adopted by breeders, trainers, and veterinarians.

 

UCD Professor in Equine Genomics and Chief Science Officer at Equinome, Emmeline Hill said the new findings would “lay the groundwork for the development of a genetic test to improve the welfare of horses that have a genetic predisposition to the disease. 

“As well as identifying horses with an increased risk of disease, this new information could also inform breeding guidance to reduce the incidence of the disease and provide targets for new therapies.”

Project lead Lisa Katz, UCD Professor in Equine Internal Medicine, added: “Understanding the genetic risk of your horse for roaring can help with early intervention and management. This might include monitoring highly predisposed horses more closely and considering surgical interventions at an earlier stage to improve treatment success.”

 

For more details, see: 

 

A genome-wide association study for recurrent laryngeal neuropathy in the Thoroughbred horse identifies a candidate gene that regulates myelin structure

Charlotte L. McGivney, Beatrice A. McGivney, Gabriella Farries, Katie F. Gough, Haige Han, Amy R. Holtby, David E. MacHugh, Lisa Michelle Katz, Emmeline W. Hill

Equine Vet J (2025)

https://doi.org/10.1111/evj.14461

Navigating the Equine Breeding Season: Mares Webinar

Are you new to horse breeding or looking to expand your knowledge? Join the American Association of Equine Practitioners (AAEP) for a free, informative webinar on the equine breeding season.

The webinar is directed toward horse owners/managers either new to breeding horses or those with limited experience. It will cover the basics of reproductive biology of the horse, logistics of the breeding season and what to expect when breeding your mare. 

The presenter is Dr. Dale Kelley, board-certified reproduction specialist at Oklahoma State University, College of Veterinary Medicine.

 

Access is free, but registration is required.

 

Details:

• Date and time : 

 

(USA) Wednesday, Oct. 30, 8:00 p.m. ET

(UK) Thursday, Oct. 31, midnight (00:00) GMT

 

• To register go to:

https://aaep-org.zoom.us/webinar/register/WN_CHkvKjmpTlGOiPMbwhEtBA#/registration

 

• Submit questions in advance through the registration form.

 

If you miss the live event, a recording will be available.

Adverse effect of bute on assisted reproduction in mares

(c) Zuzana Tillerova Dreamstime.com

 Phenylbutazone (“bute”) may not be as harmless for breeding animals as previously thought.

 Recent research from the USA indicates that bute can interfere with oocyte maturation and development after fertilization when assisted reproduction techniques are used.

 

While Thoroughbred mares often start breeding young, many other mares only begin breeding after a long working life. Many of these mares retire from work or start breeding due to orthopaedic problems that limit their performance and require regular NSAID treatment.

 

Researchers at the Texas A&M School of Veterinary Medicine & Biomedical Sciences (VMBS) have found that phenylbutazone, a non-steroidal anti-inflammatory drug (NSAID) commonly prescribed in horses, can affect a mare’s egg cells (oocytes), hindering their ability to mature into viable embryos, which is crucial for assisted reproduction.

 

The study, led by Dr Luisa Ramírez-Agámez and colleagues, looked at the effect of bute on the developmental competence of in vitro-matured equine oocytes subjected to Intracytoplasmic Sperm Injection (ICSI). Their findings are published in the journal Theriogenology.

 

In a press release, Ramírez-Agámez explained: “Mare’s oocytes need approximately 30 hours to mature in the laboratory once they have been collected before they can be fertilized. Then, we have to inject the eggs with sperm to induce fertilization, a process known as Intracytoplasmic Sperm Injection (ICSI).

 

“We discovered that phenylbutazone, commonly known as bute, can affect both the ability of a mare’s eggs to mature correctly when cultured and whether the fertilized eggs will develop into a viable embryo. In either of those cases, the eggs affected by bute cannot be used in assisted reproduction.”

 

In a preliminary study, the research team compared cumulus-oocyte-complexes (COCs) harvested from two mares treated with bute for 10 days before collection with those from four untreated mares. (The term "cumulus-oocyte complex" (COC) refers to an oocyte and the surrounding cumulus cells within the follicle. The cumulus cells are essential for the oocyte's development and maturation, providing nutrients and signals, and aiding in fertilization and embryo development.)

 

They found that oocyte in vitro maturation and blastocyst rates were lower in bute-treated mares compared to the control mares.

 

In the main experiment, nine healthy mares received a daily dose of bute (4.4 mg/kg, orally, once a day) for 10 days, while ten control mares received a placebo.

 

The researchers performed ultrasound-guided transvaginal oocyte aspiration (TVA) on days 3, 33, and 77 following the last dose of bute. The COCs recovered from both groups were matured in vitro and subjected to ICSI.

 

They observed that while the in vitro oocyte maturation rate was similar between the bute and control groups, oocyte recovery, cleavage, and blastocyst rates were significantly lower in the bute-treated group. However, these effects were short-lived, as by 33 and 77 days post-treatment, in vitro maturation, cleavage, and blastocyst rates were similar between the two groups.

 

“In a future study, we hope to determine an alternative to bute that supplies the same level of pain management but does not interfere with reproduction,” she added. “The good news is that bute’s effect on equine oocytes appears to wear off within a few weeks.

 

“We found that eggs collected three days after administration of bute were not able to produce embryos, but those collected at 33 days were successful. We hope to find a more exact answer in terms of how bute affects egg cell quality in a future study.”

 

 

For more details, see:

 

Ramírez-Agámez L, Hernández-Avilés C, Whitfield-Cargile CM, Coleman MC, Love CC. 

Treatment of mares with the non-steroidal anti-inflammatory drug (NSAID) phenylbutazone transiently affects in vitro maturation of equine oocytes and blastocyst development after Intracytoplasmic Sperm Injection (ICSI). 

Theriogenology (2024) 223:53-58.

https://doi.org/10.1016/j.theriogenology.2024.04.017

Optimising Youngstock Growth and Development

 An international panel focused on "Optimising Youngstock Growth and Development" at the Gerald Leigh Lectures on June 12, 2024. 

Organized by the Beaufort Cottage Educational Trust on behalf of the Gerald Leigh Charitable Trust, the event honours Mr. Leigh’s accomplishments as a racehorse owner and breeder and his dedication to scientific knowledge and horse welfare. The speakers included experts from the UK, USA, and Europe.

 

Key topics included:

·      Influence of prenatal maternal and environmental factors on foal athletic potential (Pascale Chavatte-Palmer, France)

·      Seasonal effects on mare and foal nutrition (Joe Pagan, USA)

·      Overview of foal purchase at public auctions (Jamie Railton)

·      Parasite resistance on UK stud farms and parasite control strategies (Professor Jacqui Matthews and Paul Overton)

·      Sustainable equine helminth control (Professor Jacqui Matthews)

·      Surgical solutions for limb deformities (Abigail Kent)

·      Raising foals for optimal performance (Dr. Rebecca Mouncey)

·      A stud manager's approach to soundness (Julian Dollar)

·      Balancing youngstock growth and development (Joe Pagan).

 

To watch recordings of the lectures (and those from previous years) go to:

 

https://www.beaufortcottage.com/news-events/category/gerald-leigh-memorial-lectures/