[Two horses with neurological symptoms: could this be equine botulism?].

This research article discusses the symptoms, diagnosis, and treatment of botulism in horses, illustrated through case studies from the Netherlands between 2003 and 2008, and proposes silage quality control as a preventive measure given the absence of a vaccine.

Overview of Equine Botulism

• Equine botulism is a feed-related intoxication in horses primarily caused by the ingestion of botulinum neurotoxin B (BoNT/B), often produced following inadequate preservation of grass silage.
• While signs of botulism vary depending on the amount of BoNT ingested, common symptoms include tongue paralysis, salvation, difficulty in swallowing (dysphagia), partial (paresis) or complete paralysis of the skeletal muscles, and signs of colic.

Diagnosis and Treatment of Botulism in Horses

• The diagnosis of botulism relies heavily on clinical signs. However, a thorough investigation of the facial nerves, such as through the ‘Tongue Stress Test’, can aid in early diagnosis.
• One of the challenges in diagnosing botulism in horses is that laboratory results often remain negative. This could be attributed to the timing of the sample collection, the high sensitivity of horses to BoNT, or antitoxin treatment.
• Botulism treatment in horses involves the earliest possible administration of antiserum, complemented by symptomatic therapy.

Prevention of Botulism in Horses

• Since the main source of botulism in horses is the ingestion of poorly preserved grass silage, ensuring the grass silage quality control can significantly reduce the risk of the disease.
• In the absence of a botulism vaccine in the Netherlands, the researchers emphasize the importance of strict quality control of silage and haylage to minimize the risk of botulism in horses.