Systematic Veterinary Bacteriology and Mycology

PATHOGENICITY

Symptoms

• In cattle, the incubation period varies between 2-10 days depending upon the dose of toxin ingested.
• Initially there will be excitation, followed by incoordination and paralysis of the hind limbs.
• There will be paralysis of muscles in the mouth, pharynx and neck, resulting in the animal being unable to swallow and the tongue protruding from the mouth. This is followed by death.
• In South Africa this condition is termed as lamsiekte in cattle caused by type D, especially in the phosphorus deficient animals.
• In poultry it results with the ingestion of type C toxin and the disease is known as duck sickness or western duck disease and Limberneck in chicken.
• The symptoms include paralysis of the wings, legs and neck, protrusion of nictitating membrane, diarrhoea and comatase before recovering in 5-6 days time.

Lesions

• Pathological changes are noticed in the CNS, especially the brain stem and 3^rd ventricle, catarrhal gastroenteritis, hepatitis and nephrosis