Special Veterinary Pathology

BOTULISM

Definition

• Botulism is a rapidly and fatal motor paralytic condition caused by ingestion of CIostridium botulinum exotoxin. Botulism is a food poisoning, the toxin being elaborated as an exotoxin by CIostridium botulinum .
• For the poisoning to occur, the toxin should be present in the food before ingestion, since the organism cannot generate the toxin in the alimentary tract

A, B, C, D, E, types

• A – Limber neck – Poultry
• D – Lamsiekte
• C – Forage poisoning in horses
• E – Fish and fish products

Incidence

• Man and chicken are usually affected
• Cattle and horse to a lesser extent
• Swine, sheep and dogs – Resistant

Transmission

• Ingestion of preformed toxin in a food source
• The source of infection for animals is almost always carrion(i.e.dead and putrefying flesh), which includes domestic, wild animals and birds

Pathogenesis

• Toxin after absorption into the blood stream enters peripheral nerves and prevents the release of acetyl choline. However toxin do not enter the central nervous system

Clinical signs

• Cattle -Pica-Chew bones (due to deficiency of phosphorus) which may contain toxin in the decaying meat and get poisoning.
• Cattle and Horse: Forage Poisoning (Ingestion of hay contaminated with dead animals or poultry litter)
• Wound botulism – Horses
• Salivation, paralysis with difficulty of movement and impaired vision.
• Tongue paralysed leads to swallowing is impossible.
• Swine are resistant since the toxin is poorly absorbed.
• Botulism in birds is exhibited by torticollis – ‘Limber neck’ caused by eating infected blow fly maggots and vegetable matter
• Head and neck droop
• Death – Respiratory failure and asphyxia
• No characteristic lesions

Diagnosis

• Symptoms
• Neutralization test using antitoxin.
• FAT
• Filtrates of suspected feed was given to mice leads to paralysis and death with “ Wasp waist appearance "