Impact of turnout rugs on horse behaviour: a study under mild weather conditions

(c) Mike Taylor | Dreamstime.com

Rugging horses is a widespread practice, commonly used to keep them warm and dry in cold, wet weather or to protect them from insects and sunlight in warmer conditions. However, rugs may also pose drawbacks — potentially causing thermal discomfort or restricting natural behaviours such as grooming and movement.

Despite the routine use of rugs, especially in the UK where spring and autumn bring relatively moderate weather, few studies have examined how horses behave with and without rugs in such conditions. A recent study by Frederick Daw and colleagues at the Royal Veterinary College, London, aimed to address this gap. The research, published in Applied Animal Behaviour Science, provides evidence that can help owners make more informed decisions about rug use to support equine welfare.

The study involved ten healthy horses, all accustomed to wearing rugs, from two different yards in southern England. Each horse was observed during 30-minute sessions, with and without a turnout rug, across several weeks. A total of 172 observation sessions were carried out, ensuring that each horse experienced both conditions in roughly equal measure.

Weather conditions during the study ranged from 1°C to 15°C, with wind speeds of 6 to 15 mph. Importantly, no signs of heat or cold stress were noted in any horse throughout the study period. The researchers analysed behavioural data using Generalised Estimating Equations (GEE), a statistical method that accounts for repeated measures on the same individuals.

The results showed a mix of both positive and negative effects associated with rugging:

·       Reduced insect-related behaviour: Horses wearing rugs exhibited significantly less tail swishing and head shaking, behaviours commonly linked to fly or midge irritation. Midges (Culicoides spp.) were observed at both sites, particularly when temperatures were higher and winds lower - conditions known to favour insect activity. These findings suggest that turnout rugs may offer effective protection against insect harassment under mild weather conditions.

·       Increased grazing at one site: At one of the two study locations, rugged horses spent more time grazing. This may reflect reduced fly irritation or increased comfort when wearing rugs.

However, the study also highlighted potential concerns:

·       Reduced movement and grooming: Horses wearing rugs were observed to walk less and perform fewer self-grooming behaviours. Both activities are considered important for physical health and psychological well-being. Their reduction may indicate that the rugs, though protective, imposed some physical restriction or discomfort  - possibly due to their weight or design.

·       Site-specific differences: The effects of rugging varied significantly between the two locations, suggesting that environmental factors and management practices also influence how horses respond to being rugged. Therefore, caution is needed when generalising these findings to other settings.

Tail swishing was found to increase with temperature (by 1.33 swishes per 1°C) and decrease with windspeed (by 0.84 swishes per 1 mph). These results further support the conclusion that environmental conditions - particularly warmth and still air - are key drivers of insect-related behaviours in horses.

This study indicates that during mild weather conditions (above 5°C), lightweight turnout rugs may help reduce insect-related discomfort in horses. However, rug choice matters: heavier or poorly fitting rugs may inhibit natural behaviour, outweighing any protective benefits.

The researchers conclude:

“When weather conditions are relatively mild (above 5 °C), horse welfare may be improved more by the use of lightweight turnout rugs for fly protection rather than heavyweight rugs designed primarily for warmth.”

They also call for further studies to test this idea more directly — in particular, by assessing the impact of purpose-designed fly rugs under mild autumn conditions, as opposed to standard waterproof turnout rugs.

For more details, see:

 

Frederick Daw, Charlotte Burn, Yu-Mei Chang, Christine Nicol,

Effect of turnout rugs on the behaviour of horses under mild autumn conditions in the United Kingdom,

Applied Animal Behaviour Science, (2025) vol 288,106661

 

https://doi.org/10.1016/j.applanim.2025.106661

Vets with Horsepower hit the road again – This time for "The Italian Job"

The motorbiking team of equine vets known as Vets with Horsepower are revving up once more
for another epic charity mission—this time through Italy and Switzerland on their latest tour, aptly named "The Italian Job."

This dedicated group of experienced equine veterinarians and lecturers combine their passion for motorcycles with their commitment to continuing professional development (CPD) and charitable giving. Since their first tour in 2010, which covered all the UK veterinary schools at the time, they’ve been delivering affordable, high-quality CPD lectures while raising money for great causes - often covering hundreds of miles a day by bike to do so!

This year’s journey kicks off on 8th July in Lodi, Italy. From there, the team will visit:

·       Perugia

·       Sassari

·       Pisa

·       Zurich, Switzerland
...before wrapping up the adventure in Saarlouis, Germany on 17th July.

Even if you're not in Italy, you can still take part. On 8th July 2025, the team will be delivering a full day of top-tier equine CPD lectures in Lodi – and the event will also be live-streamed globally for online attendees.

Your registration fee (just £10 minimum) gives you access to:

·       Live streaming of the lectures on 8th July

·       On-demand access to the recorded sessions from 10th July until 31st August 2025

All proceeds go directly to support these five outstanding charity projects:

·       Saving the Survivors – providing veterinary care to animals affected by poaching in Africa

·       The Gambia Horse and Donkey Trust – supporting working equids and their owners through vet care and education

·       Mozambique Veterinary School – training the next generation of vets in Southern Africa

·       Changing Lives Malawi – improving education and opportunities for children

·       Shy Lowen Horse and Pony Sanctuary – offering rescue and rehabilitation for horses and therapeutic services for people

Please consider donating more if you’re able—every extra pound (or dollar) makes a real difference.

https://www.vetswithhorsepower.com/2025.html

Strangles survey participants sought

Pharmaceutical company Dechra has launched a UK-wide survey aimed at increasing awareness of strangles, one of the most contagious equine diseases, and encouraging best practices in its prevention and control.

 

The short survey—designed to take just a few minutes—seeks to gather insights from horse owners about their experiences with strangles. It includes questions about disease prevention measures, biosecurity practices, and vaccination awareness.

 

Participants are also encouraged to share their opinions and personal views on strangles, helping to shape future strategies for disease control and support across the equestrian community.

 

To take part in the survey, visit: https://bit.ly/3H1o6bj

Managing insulin dysregulation in horses: a role for nutraceuticals

(c) Brian Sedgbeer Dreamstime.com

Insulin resistance (IR) and insulin dysregulation (ID) in horses are major risk factors for developing laminitis; a painful and potentially debilitating condition. While some horses are genetically predisposed to IR, diet also plays a critical role in its development. Because of this, there's growing interest in whether specific dietary strategies, including the use of nutraceuticals, can help reduce the risk.

A recent study led by Caroline Loos and her colleagues at the University of Kentucky's Gluck Equine Research Center, and published in the journal Animals,  explored whether supplementing the diet with a specific combination of nutrients could help improve insulin regulation in horses that are prone to IR. 

The trial involved 16 mature horses with a known history of insulin dysregulation. The horses were split into two groups:

• One group received a nutraceutical supplement containing omega-3 fatty acids, glutamine, vitamin E, and active yeast.
• The other group received a placebo.

Both supplements were given once daily for four weeks. During the study, horses were kept on dry lots, had free access to grass hay, and were also fed a grain concentrate twice daily (providing 0.5 g of starch per kg of body weight per meal).

To assess the horses’ insulin regulation, each underwent a Combined Glucose–Insulin Tolerance Test (CGIT) at the start and end of the trial. The CGIT is a diagnostic test commonly used in equine medicine to evaluate how effectively a horse’s body clears glucose from the bloodstream in response to insulin. During the test, horses receive a bolus (injection) of glucose and insulin, and blood samples are collected over a 150-minute period to track how quickly glucose and insulin levels return to baseline. The faster the return to normal, the better the horse’s insulin sensitivity.

After four weeks of supplementation, horses receiving the nutraceutical showed notable improvements:

• 61% faster glucose clearance compared to the placebo group.
• Shorter time for blood glucose levels to return to normal.
• Lower insulin levels at 75 minutes post-test, indicating reduced hyperinsulinemia.
• Glucose concentrations were also lower at 45 minutes post-test in the supplemented group.

In contrast, horses in the placebo group still had elevated insulin levels 150 minutes after the test, suggesting poorer insulin regulation.

These findings suggest that prophylactic use of specific nutraceuticals may help improve insulin sensitivity and reduce the risk of insulin-associated laminitis, particularly in horses consuming high-starch diets. By supporting faster glucose clearance and lowering insulin levels, this approach may offer a valuable management tool for horses at risk of ID or IR.

While more research is needed to confirm long-term benefits, this study highlights the potential of targeted dietary supplementation in supporting metabolic health in horses.

 

For more details, see:

 

Loos, Caroline, Annette Castelein, Eric Vanzant, Emma Adam, and Kyle R. McLeod. 

Nutraceutical Supplement Mitigates Insulin Resistance in Horses with a History of Insulin Dysregulation During a Challenge with a High-Starch Diet

Animals (2024) 14, no. 23: 3385. 

https://doi.org/10.3390/ani14233385