Ce. Dickinson et al., RATTLESNAKE VENOM POISONING IN HORSES - 32 CASES (1973-1993), Journal of the American Veterinary Medical Association, 208(11), 1996, pp. 1866-1871
Objective-To determine the clinical manifestations, morbidity, mortali
ty, and treatment methods for rattlesnake venom poisoning in horses. D
esign-Retrospective analysis of medical records. Animals-27 horses wit
h acute venom poisoning attributable to prairie rattlesnakes, and 5 wi
th chronic problems subsequent to a rattlesnake bite. Results-Most hor
ses were bitten on or near the muzzle while on pasture, resulting in h
ead swelling, dyspnea, and epistaxis. Additional manifestations of acu
te poisoning included fever, tachycardia, tachypnea, cardiac arrhythmi
a, hemolytic anemia, thrombocytopenia, hemorrhage, thrombosis of venip
uncture sites, colic, diarrhea, and prehensile and masticatory dysfunc
tion. Chronic problems included cardiac disease, pneumonia, laminitis,
pharyngeal paralysis, and wound complications. The most common chroni
c problem was cardiac disease. The most commonly used treatments were
antibiotics, nonsteroidal anti-inflammatory drugs, tetanus prophylaxis
, and airway support. Mortality in the 27 acutely affected horses was
18.5%; the overall mortality was 25%. Clinical Implications-Horses bit
ten by prairie rattlesnakes may develop multiple, often severe, acute
or chronic manifestations oi poisoning involving various organ systems
. Thorough clinical evaluation, effective treat ment, supportive care,
and close observation are indicated in horses with rattlesnake venom
poisoning.