Brucellosis is a zoonotic reproductive disease caused by different species of Brucella bacteria in different species of farm animals. It is also known as Undulant Fever, Bang's Disease or Contagious Abortion of Cattle.
Great Britain is Officially Brucellosis Free (OBF), and has been since 1985. Sporadic cases are still seen. Animals imported from non-officially free countries pose a risk and are tested after import or after their first calving post import. Northern Ireland was the most recent part of the UK to achieve OBF status, in September 2015. Brucellosis is a Notifiable Disease, so suspicion of disease must be reported to the APHA on 03000 200 301. Because the clinical signs associated with the disease are non-specific (see below), any bovine abortion must be reported to that number. Bovine abortion in this instance is defined as 'an abortion or calving which takes place less than 271 days after service, or 265 days after implantation or transfer of an embryo, whether the calf is born dead or alive'. Following reporting of an abortion, the APHA will make a decision as to whether Brucellosis investigation is required. In most instances, investigation is not required in dairy herds, as quarterly bulk tank testing is completed as routine monitoring. Details can currently be found here: http://apha.defra.gov.uk/External_OV_Instructions/Brucellosis/Surveillan...
The Brucella species which affect different farm animals are:
|Farm animal species||Brucella species|
|Sheep and goats||Brucella mellitensis|
Clinical signs of brucella infection:
- abortion or premature calving
- retention of fetal membranes
- placentitis (brown slimy cotyledons, thickened inter-cotyledonary regions)
- swollen testicle(s) in entire male animals
Brucellosis is very contagious, with the aborted calf, the fetal membranes and the uterine fluids all containing large quantities of bacteria.
Diagnosis is by serological testing of blood or individual milk samples. Or by culture of aborted foetus, foetal membranes, swab of vaginal mucous or milk.
Since the country is free of this disease, treatment of positive animals is not allowed - all infected and in-contact animals must be slaughtered. For this reason, the quarantine of animals imported from non-OBF countries is absolutely vital until they have tested negative following first calving in UK.
Evolution Farm Vets are part of a pilot scheme in the Wessex region whereby cattle abortions can be reported to the vets, rather than direct to APHA. The hope is that this will increase the reporting of abortions and allow a more complete surveillance for Brucellosis.