Do ponies avoid salt in drinking water?

 Ponies accept drinking water containing low levels of salt and this could potentially be used to help rehydration, according to a recent study.

 Horses lose heat by sweating and in doing so lose sodium as well as water. Sodium plays an important role in numerous functions throughout the body. An increase in plasma sodium concentration is a trigger for thirst.

 

Horse sweat contains high levels of sodium (Na). Excessive sweating may result in the loss of so much sodium that the plasma sodium concentration does not increase enough to trigger drinking. So heavily sweating horses may not voluntarily drink enough water to replenish their body fluids.

 

Could dilute saline solutions be used as drinking water to help combat sodium loss and dehydration? 

 

A study in Germany by Nick Enke and colleagues assessed whether Shetland ponies would notice and tolerate different salt (NaCl) concentrations in their drinking water.

 

Six non-pregnant and non-lactating mares were enrolled in the study, which consisted of three phases. In the first phase only fresh water was provided, as a control. In the second phase, a pairwise-preference test, ponies were given a choice between fresh water and one of six different saline solutions. Finally, the ponies were offered a choice of fresh water and five different NaCl concentrations at the same time.

 

A full report of the work is published in the Animal Science Journal.

 

The researchers report that during the pairwise test, the ponies did not distinguish between fresh water and 0.25% NaCl-water, but demonstrated a clear preference for water containing 0.5%NaCl. Ponies consistently avoided NaCl concentrations above 0.75%. During the free-choice test, the ponies showed a pronounced preference of fresh over saline water. 

 

They noted that sodium intake from a salt lick was not reduced in response to higher sodium intakes in the water. 

 

They conclude: “The ponies exhibited a remarkable sensory discrimination capacity to detect different NaCl concentrations in their drinking water. The acceptance of solutions with low NaCl levels (0.25/0.5%) without adverse effects demonstrates potential as rehydration solution for voluntary intake.”

 

 

For more details, see:

 

Sensitivity of ponies to sodium in the drinking water

Nick Enke, Lea Brinkmann, Karl-Heinz Südekum, Ernst Tholen, Martina Gerken

Anim Sci J (2022);  93(1):e13697.

https://doi.org/10.1111/asj.13697

Effect of blue light on pregnancy outcomes

 It has been known for a long time that changing daylength influences equine reproduction. 

The natural breeding season for horses occurs during the brighter months of the year (April onwards in the northern hemisphere). This presents a challenge for breeders that require foals to be born early in the year, and has led to the search for ways to advance the onset of reproductive activity

 

Using stable lighting to artificially prolong the daylight to 16 hours from mid December onwards has been used to stimulate the onset of oestrus activity in mares. Research by Dr Barbara Murphy demonstrated that a similar effect could be produced by shining a low intensity blue light into one eye.

Professor Christine Aurich and her research team at the University of Veterinary Medicine in Vienna, Austria have been investigating the effect of blue light treatment on gestation length, and pregnancy outcome. A full report is published in Domestic Animal Endocrinology.

Twenty pregnant Warmblood mares, each carrying a single pregnancy completed the study, which covered two consecutive years. The mares were kept at the Brandenburg State Stud at Neustadt, Germany. During one pregnancy the mares wore a mask* which directed 50 lux blue LED light (468nm) into one eye from 08.00 to 23.00 daily from mid- December onwards. During the second pregnancy the same mares received no treatment, and so acted as controls.

 

The researchers found that pregnancy length was shorter in blue LED light-treated mares than in controls. Foals born to blue LED light-treated mares had lower wither heights, but were of similar weights and took less time to stand after birth than did control foals. 

 

They also noticed differences in hair growth. Foals born to light-treated mares had reduced hair length compared to controls and hair regrowth in treated mares was reduced.

 

They conclude: “foaling can be advanced with head-worn masks emitting blue LED light to a single eye without negative effects on foal maturity. Blue LED light resulted in the birth of slightly smaller foals compared to controls. Furthermore, foals born to blue LED light-treated mares had a shorter hair coat than control foals, demonstrating that artificial light directed at the mare does reach its fetus and accelerates fetal maturation.”

 

* Equilume Light Mask

 

For more details, see:

 

Effects of blue monochromatic light directed at one eye of pregnant horse mares on gestation, parturition and foal maturity

A Lutzer, C Nagel, B A Murphy, J Aurich, M Wulf, C Gautier, Christine Aurich 

Domest Anim Endocrinol (2022)78:106675.

https:doi.org/10.1016/j.domaniend.2021.106675

Effect of temperature on cyathostomin larval development

The cyathostomins (small strongyles) are the most important group of intestinal parasites of the horse - both numerically, and through their ability to cause disease. Furthermore, they are becoming increasingly difficult to control as they develop resistance to the drugs used against them. 

 Infected horses pass eggs in the manure, contaminating the pasture. These eggs are not infective straight away but need time to develop into the infective third stage larvae (L3).

 

In a laboratory study, researchers investigated the effect of different temperatures on the minimum time taken by cyathostomin eggs to develop into first/second stage larvae (L1/L2), and into infective third stage larvae (L3) in horse faeces.

 

Dr Aurélie Merlin and colleagues assessed the effect of three constant temperatures (10°C, 23°C, 30°C) under laboratory conditions and one fluctuating temperature (mean: 17 ± 4 °C) under outdoor conditions.

 

Their results, published in Veterinary Parasitology: Regional Studies and Reports, show that, depending on temperature, the minimum time taken by eggs to develop into L1/L2 was between 1 and 3 days. The minimum time to develop into L3 was between 4 and 22 days. Development of the eggs to infective L3 larvae was slowest at 10°C and fastest at 30°C.

 

The researchers suggest that their findings will help improve mathematical modelling of parasitic risks in grazing horses.

 

The results support the practice of removing droppings at least twice a week, which should prevent significant contamination of the pasture.

 

 

For more details, see:

 

Effect of temperature on the development of the free-living stages of horse cyathostomins

A Merlin, N Ravinet, C Sévin , M Bernez-Romand, S Petry, M Delerue, L Briot, A Chauvin, J Tapprest, L Hébert 

Vet Parasitol Reg Stud Reports (2022) 28:100687

https://doi.org/10.1016/j.vprsr.2022.100687

Prospect of easier remote monitoring

 Remote monitoring of heart, muscle and breathing conditions may become easier following the development of an e-textile slicker (or rug) at Purdue University. 

Biomedical engineers and veterinarians have collaborated to produce the system that can monitor a horse’s cardiac, respiratory and muscular systems using Bluetooth technology. The e-textile garment can be used for long-term management of chronic health conditions in large animals, with the goal to have a version for human use.

 

Another advantage of the e-textile is that veterinarians and their support staff won’t have to shave the horse’s hair or use adhesives to place electrodes on the horse’s skin, which should make it more comfortable for the horse.

 

Findings of how the e-textile works is featured in a study published in the journal Advanced Materials.

Chi Hwan Lee, the Leslie A. Geddes associate professor of biomedical engineering in Purdue’s Weldon School of Biomedical Engineering, said the Purdue team developed a dual regime spray and technique to directly embed a pre-programmed pattern of functional nanomaterials into the fabric to add the e-textile capabilities.

 

“These specially designed e-textiles can comfortably fit to the body of humans or large animals under ambulatory conditions to collect bio-signals from the skin such as heart activity from the chest, muscle activity from the limbs, respiration rate from the abdomen or other vital signs in an extremely slight manner,” Lee said. “Our technology will significantly extend the utility of e-textiles into many applications in clinical settings.”

 

The team’s next steps involve developing continuous 24-hour monitoring of horses with chronic disease or those receiving care in a veterinary ICU.

 

“We believe that our technology will be helpful in diagnosis or management of chronic diseases,” Lee said, especially as demand increases for remote health monitoring.

 

“Remote health monitoring under ambulatory conditions would be useful for farm and household animals, as it could potentially minimize clinic visits, especially in rural areas. It would also increase the efficiency in managing a large number of farm/household animals at once from a distance, even overnight,” he added.

 

A real-life example would be the ability to monitor severe equine asthma, which affects 14% of adult horses.

 

“Continuous monitoring would allow early detection of disease flair-up before it gets serious, offering an opportunity to nip it in the bud,” said Laurent Couëtil, a professor of large animal internal medicine in Purdue’s College of Veterinary Medicine and collaborator in the study. “Remote monitoring opens the possibility of sending vital information to the veterinarian to help make timely and informed treatment decisions.”

 

For more details, see:

 

A Programmable Dual-Regime Spray for Large-Scale and Custom-Designed Electronic Textiles

Taehoo Chang, Semih Akin, Min Ku Kim, Laura Murray, Bongjoong Kim, Seungse Cho, Sena Huh, Sengul Teke, Laurent Couetil, Martin Byung-Guk Jun, Chi Hwan Lee

Advanced materials (2022) Vol 34, 2108021

https://doi.org/10.1002/adma.202108021

Is your mare due to foal?

Researchers at the Western College of Veterinary Medicine in Saskatoon, Canada, would like your help.

They are investigating how umbilical cord variations relate to  foal health. In particular, they are interested in the length of the cord, and the number and type of twists present in it. 

In light horses, the umbilical cord is usually between 30 and 80 cm long and may be twisted a few times. Excessively long cords, or those with numerous twists, may limit blood flow and affect the foal’s health.

 

Dr. Madison Ricard, a veterinary anatomic pathology resident, who is leading the study, is looking for owners of pregnant mares to take part in the research. 

 

Participation in the study will involve measuring the length of the umbilical cord after foaling and taking a photo of the umbilical cord. 

 

Information will be recorded about the mare, the foaling process, and the foal’s health at birth. There will be follow up surveys regarding the foal’s health at 7 and 30 days after birth.

 

To participate in the study, or for more details, go to:

https://wcvm-equs.ca

Have you organized an equestrian event in Ontario?

 
The COVID-19 pandemic and recent Equine Herpes virus outbreaks have highlighted the need for enhanced biosecurity at equine events. 

An Ontario Veterinary College research study would like to interview equestrian competition organizers (within the past 5 years) about their experiences and perspectives towards biosecurity at equestrian events in Ontario, Canada.

 

If you are interested in participating in this study, they ask that you read the full details and complete the pre-interview questionnaire:

 

https://uoguelph.eu.qualtrics.com/jfe/form/SV_cZ2dgMpIFSy0Prg?jfefe=new