Beef cattle production and management
Practical Action
Contagious abortion (CA) is an infectious disease of cattle that affects the reproductive organs.
CA is caused by a bacterium. Discharges from animals that have aborted contaminate drinking
water, pastures and bedding which on ingestion by health animals results in infection.
Occurrence
The disease in not seasonal and can occur at any time of the year. It is common in intensively
reared cattle particularly dairy cattle. Farmers and veterinary personnel attending to infected
cattle or people drinking untreated milk can get the infection.
Clinical Signs
Cattle that are not pregnant do not show signs at all. Pregnant animals exhibit the following
signs:
They abort in late pregnancy
Stillbirths at full term
Cattle can give birth to weak calves
Retained afterbirth
Increased incidence of metritis (inflammation of the uterus) and prolonged calving to
conception intervals.
Swollen testicles in bulls is a sign of infection. In other animals the infection can present as
a localized swelling of the knee or hock.
Diagnosis
Diagnosis is based on history (abortion storms) and clinical signs. The bacteria can also be
isolated from aborted calves, vaginal discharges and milk. Antibodies against the disease can be
demonstrated in blood collected from the dam.
Treatment
The disease cannot be treated.
Control
Control is based on culling all infected animals and vaccination of all female cattle between the
ages of 3 and 8 months old. The vaccination is done once and offers life-long protection.
Lumpy skin disease (Chirwere Chemapundu)
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