Brucellosis in Pigs

Causal agent	Brucella suis biovars 1,2 and 3. Biovar 4 occurs in Reindeer and Caribou, whereas Biovar 5 is in mice. Brucella is a bacteria
Age group	All ages can be infected
Clinical signs
	Generally no clinical signs exhibited by infected animals	Brucellosis suis in a testes
Sows	Can cause abortion, infertility and severe metritis
Boars	Can cause orchitis (infection of testes) and infertility
Piglets, Weaners	Posterior paralysis and lameness
Infectivity
	The major route of infectivity is through contact with another pig. Venereal transmission is possible. Note many other mammals (wild and domestic) can carry and potentially transmit Brucella suis to pigs. In Europe B. suis biovar 2 occurs in the Hare
Post-mortem Lesions
	Generally none. Many be abscessation sometime with necrosic foci in the liver. Metritis and orchitis
Diagnosis
	Serological examination. This has been a requirement for exporting pigs around Europe, but is now not required. The UK is free of Brucella suis but it is endemic in the wild boars of Europe.
	Note the relatively common organism Yersinia enterocolitica O:9 share a common antigen and this will cause false positive results.
Treatment
Individual	None
	This is a reportable disease. Depopulation is the only viable option
Control	Through good national and herd biosecurity measures
Zoonotic implications
	Brucella is a serious zoonotic disease and causes ‘undulating fever’ in man. This however, is primarily an occupational hazard. Note Yersinia enterocolitica is also a zoonotic disease causing diarrhoea