Livestock production: What to do if your herd tests positive for brucellosis (contagious abortion)


By Digital team | 9 January 2018
abortion, creep; placenta

Question: What should one do if your herd tests positive for contagious abortion (brucellosis)?

If a farmer is doubtful about, or not satisfied with, the test results, he or she should discuss them with a State Veterinarian (in South Africa) or equivalent official in other countries.

It is also important that farmers act on scientific facts rather than believing every farmer who has a grudge or a theory.

  • Do not overreact if your cows test positive, and impulsively slaughter them.
  • If they calve and do no abort, keep them apart, away from the bull.
  • Test them again, at least 3 times, over a 12-month period rather than indiscriminately slaughtering them.
  • If heifers test positive, keep them separate from the herd for at least 12 months before having them tested again.
  • I know of people who have sold so-called positive heifers for slaughter and then afterwards saw the cows with claves at foot in someone else’s kraal.
  • If the original owner then says the cows had brucellosis, the current owner could say he has had them tested for 2 years and that they tested negative.
  • Cows really suffering from contagious abortion excrete thousands of brucellosis organisms.
  • When they calve, the grazing is also infected.
  • The organisms can survive for many months in a cool, moist environment.
  • Although an infected cow usually only aborts once and then calves normally, she still infects the environment every time she calves – they really are wandering time bombs.
  • Such cows should, preferably, be slaughtered.

Also read: Livestock production: Testing your herd for brucellosis (contagious abortion)

  • This article was written by Dr. Matt Ekron and appears in Ask the vet: What cattle farmers should know (1), compiled by Dr. Faffa Malan.