Elapid snake envenomation in horses: 52 cases (2006-2016)

Area of Science:

• Veterinary Neurology
• Toxicology
• Animal Health

Background:

• Snake envenomation is a significant global threat to animal health, causing considerable morbidity and mortality.
• While crotalid (pit viper) envenomation in horses is well-documented, elapid snake envenomation remains poorly characterized.
• This study addresses the knowledge gap regarding elapid snake envenomation in Australian horses.

Purpose of the Study:

• To delineate the clinical presentation, diagnostic findings, treatment strategies, and outcomes for horses diagnosed with elapid snake envenomation in Australia.
• To enhance understanding of this specific type of snakebite in equine populations.

Main Methods:

• A retrospective case series design was employed, analyzing medical records from 2006 to 2016.
• Inclusion criteria included observed snakebite, positive snake venom detection kit (SVDK) results, clinical response to antivenom, or supportive post-mortem findings.
• Data were collected from multiple university and private veterinary practices.

Main Results:

• Fifty-two cases of elapid snake envenomation were identified.
• Ninety-four percent of cases exhibited neurotoxicity, primarily generalized neuromuscular weakness, with associated signs like staggering gait and muscle fasciculations.
• Concurrent conditions included rhabdomyolysis (50%) and hemolysis (19%).
• The overall survival rate was 86% for horses receiving antivenom, with 43% requiring more than one vial.

Conclusions:

• Elapid snake envenomation in horses is predominantly a neuromuscular syndrome, often lacking clear bite sites or history.
• In endemic regions, consider elapid envenomation in horses presenting with generalized neuromuscular weakness, altered mentation, rhabdomyolysis, or hemolysis, particularly during warmer months.
• Response to antivenom is the most reliable method for confirming the diagnosis.