Aetiology
The infection is caused by staphylococcus bacteria mainly Staphylococcus aureus but frequently the mycoplasmas, pasteurella and Mycobacterium avium may occur following septicaemia.
Age/host range
The disease is seen in chickens and turkeys. It is most common in adult birds generally initiated by injury to the foot pad or ball of the feet.
Morbidity and mortality
Morbidity is usually low and mortality is 0-15% though affected birds will often be culled on humane grounds.
Transmission
Infection results from wounds either accidental or induced by interventions such as beak trimming and toe trimming. They are the means of transmission of the organism.
Damaged skin due to nutritional deficiencies such as biotin deficiency can be a point of entry of the organism.
Clinical signs
Ruffled feathers
Lameness
Low morbidity
Swollen hock joint and feet
Some sudden deaths from acute septicaemia.
Post-mortem lesions
Tenosynovitis, most frequently in the plantar surface of the foot or above the hock joint. This may progress to abscess formation in these areas.
Infected joints may have clear exudates with fibrin clots.
Diagnosis
Tentative diagnosis is based on clinical signs and post-mortem lesions. Confirmation is based on isolation and recognition of pathogen.
Differential diagnosis
Septicaemia due to colibacillosis, salmonella species and tenosynovitis due to Mycoplasma species especially Mycoplasma synoviae.
Treatment
Antibiotics in conformity with sensitivity.
Prevention
Proper sanitation.
Good hygiene in the nest, the hatchery and in any intervention or surgery processing such as toe clipping.