Starved Horses: Each Body Score Improves Survival by 1,500%

When it comes to saving starved horses, body condition has a major impact. For every point higher they score on the nine-point Henneke body condition scale, they’re nearly 15 times more likely to survive, new study results show.

While body weight, rectal temperature, and white blood cell counts can give critical clues about a horse’s prognosis, body condition score is the only factor that reliably helps predict whether the animal will live past the first 100 days post-rescue, said Jennie Ivey, PhD, assistant professor and extension equine specialist in the University of Tennessee Institute of Agriculture’s animal science department, in Knoxville.

“As a reflector of the animal’s overall nutritional status, body condition can indicate that other things are happening under the surface when the horse has been without quality nutrients for so long,” Ivey said. “So body condition score really seems to let us look at these (welfare) cases with a bit of a more objective lens.”

After six years watching welfare cases arrive in the university’s veterinary hospital, Ivey decided to work with her colleagues to find indicators that could predict which mistreated equids would have a reasonable chance of survival—including the recovery process. Starved horses, donkeys, and mules usually have difficulty recovering from starvation because they can no longer handle certain amounts of the nonstructural carbohydrates they require to gain weight. As a result, they can develop potentially fatal refeeding syndrome.

“There are just such challenges and difficulties in refeeding these populations,” she said. “So it’s really important to consider whether going that route (of extended therapeutic efforts to save a malnourished horse) and taking the risk to help the welfare of that animal really make the best choice, for a number of reasons.”

To look for early signs that might flag horses as more or less likely to recover from starvation, the researchers analyzed the hospital records of 82 starved equids collected over 11 years at their university. Checking statistics regarding body condition, bloodwork, vital signs—heart rate, respiratory rate, rectal temperature, body weight—and parasite loads at the time each horse was admitted, they found a few factors that could help predict their chances of survival.

White blood cell counts were higher and body temperature was slightly lower in horses that didn’t survive, Ivey said. Even so, these differences weren’t significant enough to suggest whether horses would survive the first 100 days of treatment.

One factor that stood out, however, was the horse’s body condition score at the time of arrival at the hospital. Survival likelihood increased 14.6 times for each full point increase in condition on the nine-point scale, she said.

“I wish that we had found something else that could have been the linchpin that everybody hopes for,” Ivey said. “But in the end, given its quality as a reflector of the animal’s overall nutrition status, I’m not surprised that we only found body condition.”

The Study “Clinical Factors Associated With Survival Outcomes in Starved Equids: A Retrospective Case Series,” was published in the Journal of Equine Veterinary Science.