Rattlesnake venom poisoning in horses: 32 cases (1973-1993).
OBJECTIVE
To determine the clinical manifestations, morbidity, mortality, and treatment methods for rattlesnake venom poisoning in horses.


METHODS
Retrospective analysis of medical records.


METHODS
27 horses with acute venom poisoning attributable to prairie rattlesnakes, and 5 with chronic problems subsequent to a rattlesnake bite.


RESULTS
Most horses were bitten on or near the muzzle while on pasture, resulting in head swelling, dyspnea, and epistaxis. Additional manifestations of acute poisoning included fever, tachycardia, tachypnea, cardiac arrhythmia, hemolytic anemia, thrombocytopenia, hemorrhage, thrombosis of venipuncture sites, colic, diarrhea, and prehensile and masticatory dysfunction. Chronic problems included cardiac disease, pneumonia, laminitis, pharyngeal paralysis, and wound complications. The most common chronic 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%.


CONCLUSIONS
Horses bitten by prairie rattle-snakes may develop multiple, often severe, acute or chronic manifestations of poisoning involving various organ systems. Thorough clinical evaluation, effective treatment, supportive care, and close observation are indicated in horses with rattlesnake venom poisoning.
Dickinson
C E
CE
Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523, USA.
Traub-Dargatz
J L
JL
Dargatz
D A
DA
Bennett
D G
DG
Knight
A P
AP
D000818:Animals; D003120:Colorado / Q000453:epidemiology; D003435:Crotalid Venoms / Q000506:poisoning*; D017839:Crotalus; D003645:Death, Sudden / Q000209:etiology / Q000662:veterinary; D005260:Female; D005500:Follow-Up Studies; D006734:Horse Diseases / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy; D006736:Horses; D008297:Male; D009017:Morbidity; D012189:Retrospective Studies; D012909:Snake Bites / Q000453:epidemiology / Q000628:therapy / Q000662:veterinary*
D003435:Crotalid Venoms