The Otherwise Apparently Healthy Collapsing Horse

Causes of collapse in apparently healthy horses range from sleep deprivation and pain to muscle disorders and pregnancy.

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The Otherwise Apparently Healthy Collapsing Horse
Horses need paradoxical, or deep, sleep (aka rapid eye movement, or REM sleep) just like we do, said Bertone. | Photo: iStock
Stray voltage. Sleep terrors. Melatonin. Medical marijuana. These ingredients made up a lively lunchtime table topic veterinary discussion about horse collapse—a condition with primary causes ranging from sleep deprivation and pain to muscle disorders and pregnancy.

Key to treating a collapsing horse successfully is pinpointing the cause, which can take some sleuthing.

Joe Bertone, DVM, MS, Dipl. ACVS, and Stephen Reed, DVM, Dipl. ACVIM, described their approaches to these cases while moderating the discussion at the 2016 American Association of Equine Practitioners Convention, held in December in Orlando, Florida. Bertone is a professor of equine medicine at Western University of Health Science’s College of Veterinary Medicine, in Pomona, California, and has a special interest in sleep deprivation. Reed is an internist and shareholder at Rood & Riddle Equine Hospital, and his bailiwick is equine neurology; this means he sees a steady caseload of what he sometimes calls “clumsy horses,” or uncoordinated animals because of neurologic disorders. Both veterinarians possess an infectious enthusiasm for difficult-to-diagnose cases.

When Bertone gets a call about a collapsing horse, 90% of the time the horse is sleep-deprived. The other 10% of the time the horse is suffering solely from a neurologic, musculoskeletal, or other type of condition. Common reasons Bertone sees for horses collapsing that could fit in the sleep-deprivation category include boredom (think of a show horse collapsing in the crossties at 4 a.m. while being braided), dominance displacement (when an aggressive gelding keeps vigil and, thus, never sleeps), and the pain and pregnancy mentioned earlier

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Written by:

Stephanie L. Church, Editorial Director, grew up riding and caring for her family’s horses in Central Virginia and received a B.A. in journalism and equestrian studies from Averett University. She joined The Horse in 1999 and has led the editorial team since 2010. A 4-H and Pony Club graduate, she enjoys dressage, eventing, and trail riding with her former graded-stakes-winning Thoroughbred gelding, It Happened Again (“Happy”). Stephanie and Happy are based in Lexington, Kentucky.

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