Finding a horse recumbent (unable to rise after lying down) is a nightmare no horse owner wants to experience. Once a horse is recumbent, veterinarians often offer a poor prognosis. But according to Laramie Winfield, DVM, of the University of California (UC), Davis, College of Veterinary Medicine, owners and their veterinarians should evaluate several factors before giving up hope on a recumbent horse.

At the 2011 American College of Veterinary Internal Medicine Forum, held June 15-18 in Denver, Colo., Winfield discussed a retrospective study that reviewed medical records of 101 horses with a history of recumbency admitted to the UC Davis Veterinary Teaching Hospital from 1995-2010 to determine which factors were associated with their survival. Many different diseases and ailments can spur recumbency, including equine protozoal myeloencephalitis, central nervous system disorders that cause brain diseases, spinal cord problems (such as wobbler syndrome), botulism (a neurologic disease caused by a neurotoxin produced by the bacterium Clostridium botulinum), adverse reactions following general anesthesia, musculoskeletal disease, parasite infestations, tetanus, and pneumonia.

The average age of case horses was 10 years. Three-quarters of hospitalized horses received veterinary treatment in the field prior to transfer to the referral clinic, and the overall survival rate for the recumbent horses was 30% with an average hospitalization cost of $3,200.

Winfield discussed several factors consistent with a poor outcome including spinal cord disease, botulism, and ataxia (incoordination) in horses that were not yet recumbent, or increased BUN (kidney enzyme) on laboratory blood tests. An elevated BUN could be indicative of kidney disease, which is a problem in recumbent horses due to a risk of dehydration, muscle damage, and poor bladder function