A NEW WAY TO SEE STRESS

Determining whether your horse is stressed can be as simple as looking into his eyes.

According to a recent Canadian study, horses in challenging situations blink less often than do those who are calm.

Researchers at the University of Guelph videotaped 33 horses in four different situations: standing in a familiar paddock with a herdmate; having feed withheld at the normal mealtime; being visually separated from their herdmate; having a ball suddenly thrown onto the ground in front of them. All the horses were also fitted with heart rate monitors that collected data every five seconds during the three-minute study periods.

When researchers analyzed the videotapes for eyelid activity, they found the horses blinked an average of eight to nine times per minute during calm periods, when standing in a familiar paddock. However, when their feed was restricted, they were separated from their peers or they were startled, the horses blinked less often. During periods of feed restriction and separation, the horses blinked about five times per minute, and when the ball was thrown to startle them, they blinked about four times per minute.

In addition, the data showed that the horses’ heart rates increased and the muscles around their eyes twitched more frequently during the feeddeprivation periods.

The researchers say all of this information can be used as a noninvasive method of determining whether a horse is stressed.

Reference: “Eye blink rates and eyelid twitches as a noninvasive measure of stress in the domestic horse,” Animals, August 2019 their hay---had larger sand accumulations than did horses who often left some uneaten. “I am not always sure if [the problem of sand accumulation is related to] the soil, or the habit of keeping horses out most of the time during a long season without proper grass,” says Niinistö. “We have some horses who have the habit to try to find food anywhere.”

Regardless of whether sand ingestion is intentional, prevention is the best course of action, says Niinistö, who notes that sensible feeding practices can reduce the inadvertent ingestion of soil.

“I would avoid giving food from the ground, and try to give horses something to chew on---spruce or willow branches or whatever wood they like that is not toxic---if they are too fat to eat all the time,” she says. “Some horses just need to be muzzled. I would treat the susceptible horses with psyllium a few times a year, and if there is any doubt, take x-rays to confirm or rule out the sand.”

Reference: “Ownerreported clinical signs and management- related factors in horses radiographed for intestinal sand accumulation,” Journal of Equine Veterinary Science, May 2019