RESEARCH LINKS DIET AND BEHAVIOR

A University of Glasgow study confirms something that owners of feisty ponies have long observed---diets high in starch can contribute to “spookier” behavior.

To investigate possible correlations between behavior and the gut microbiome, the researchers used 10 untrained ponies. For two weeks, half of the ponies received a high-starch ration, and half were fed a high-fiber diet. The rations were then switched for an additional two-week period.

At the end of each 14day feeding period, the researchers collected fecal samples from each pony and extracted DNA data from the bacteria present. They also performed two tests to gauge how the ponies reacted to various stimuli.

In the first test, an unfamiliar person stood passively in a small area with each pony. For the second test, each pony was released into an area where a novel object (a road sign or a box wrapped in tinfoil) had been placed next to a bowl of feed. The researchers documented each pony’s behavior in detail.

They found that the ponies were more reactive when they were on the high-starch diet, demonstrating a heightened state of alert when confronted with the novel object, as well as what the researchers called “unsettled behaviors” in response to the passive human.

In addition, the DNA analysis indicated that the composition of gut bacterial populations was influenced by the different diets that the ponies received.

Comparing the behavior data to the genetic data, the researchers concluded that “correlative relationships exist between dietary induced alterations to fecal microbiota and behavior,” and that “dietary induced alterations to gut microbiota play a role in affecting the behavior of the host.”

Reference: “High-starch diets alter equine faecal microbiota and increase behavioural reactivity,” Scientific Reports, December 2019

muscle training (IMT) entails breathing through a device that imposes resistance to inhalation. “IMT trains both the upper airway muscles and the respiratory pump muscles, that is, the diaphragm,” explains Kate Allen, BVSc, PhD of the University of Bristol, who worked with Laura Fitzharris, BVSc, MRCVS, on the study. “The muscles are the same type as the leg and locomotor muscles, and therefore should respond to appropriate training.”

IMT has recently become popular among human athletes looking to improve respiratory performance, so the Bristol researchers decided to explore the feasibility of using the technology in horses.

Indeed, says Allen, the potential benefits of

IMT may be even greater in horses than in people. “Human performance is limited by cardiovascular capacity whereas the racehorse’s performance is primarily limited by respiratory function,” she says. “Conventionally, cardiovascular fitness involves training all components of the body in equal amounts whereas IMT involves training the respiratory system in isolation. By improving the fitness/function of the respiratory muscles, they work at a lower percentage of their maximum during global performance.”

For the Bristol study, 10 Thoroughbreds in training for steeplechase racing were gradually acclimated to wearing a mask fitted with valves to control the level of resistance to each inhalation. Over a nine-week period, the horses underwent IMT five days a week, breathing through the mask while standing still. During each session, the horses took 30 “loaded” breaths,

Inspiratory muscle training became popular among human athletes looking to improve performance, so researchers decided to investigate the feasibility of using the technology in horses.

rested for approximately two minutes, then took 30 more. The resistance was increased every four days, but the protocol allowed increases or decreases in the intensity of the effort to be adjusted depending on the horse’s response. The horses continued their normal race training and competition schedules during both study periods. Tests of respiratory strength were made before and after the IMT.

The resulting data showed that the horses tolerated IMT well and that it can be introduced to commercial training yard.

Based on these findings, the researchers conclude

IMT in horses is feasible.

The next step, Allen says, is to correlate IMT to physiologic or performance changes: “We are currently investigating the use of IMT for the treatment and prevention of upper airway collapse, and the effect on athletic performance. In humans there are widespread uses in a range of medical conditions, but it will take us a while to investigate all of these in the horse.”

Reference: “Inspiratory Muscle Training and Testing: Rationale, Development and Feasibility,” Equine Veterinary Journal, December 2019

Researchers confirm that some diets seem to contribute to “spooky” behavior in horses.

ALL HEART: Inspiratory muscle training may be especially beneficial for horses because their performance is primarily limited by their respiratory—rather than cardiovascular—capacity.