- Bovine brucellosis:
- Caused by Brucella abortus
- Eradicated in many countries including UK
- Infection usually by ingestions but also venereal, skin abrasions, inhalation, transplacental
- Abortion storms in susceptible herds
- Abortion after fifth month of gestation due to placentitis
- Brucellae excreted in foetal fluids for 2-4 weeks following abortion and at subsequent parturitions without abortion
- Infection of mammary glands and lymph nodes persists for years
- Excreted intermittently in milk for years
- Seminal vesicles, ampullae, testicles and epididymus infected in bulls; necrotising orchitis
- Decreased fertility in cows and bulls; decreased milk production
- Localisation in spleen and lymphatic tissue of non-pregnant animals
- Occasionally causes arthritis
- Isolated from closed cases of poll evil and fistulous withers in horses
- Brucella abortus
- Uncommonly localises in joints
- Usually in carpal bursitis (hygroma) in cattle and bursitis in horses
- Brucella abortus
Affects cattle, transmission is by ingestion and abortion occurs in last half of pregnancy. Placenta is covered by fibrinonecrotic tissue. Foetus often shows bronchopneumonia.