Do Hormones Heighten Mareish Behavior?

A common refrain from horse owners and caretakers is that mares become more moody and misbehave more when they are in estrus.

A study from the University of California, Davis, investigated whether elevated ovarian hormones were linked to a change in mare behavior, reports EQUUS magazine. A study team reviewed hormone profiles of 2,914 mares referred to the UC Davis Clinical Endocrinology Laboratory and the Equine Reproduction Service. The focuses on mares whose histories included the words “behave,” “behavior” or “behaving.”

The researchers then analyzed the data to see whether there was an association between reported abnormal behavior and testosterone concentration or concentrations of any other hormones produced by the ovaries. They found that abnormal behaviors were associated with elevated hormones in less than 10 percent of the sample cases.

Mares that exhibited stallion-like behaviors of biting, vocalizing or mounting other horses, however, did have elevated hormone levels.

Read more at EQUUS magazine.