Brucellosis (Contagious Abortion)

  • An important bacterial disease of cattle and buffalo.
  • Leads to loss in milk production, loss of calf, birth of weak or diseased calf ,repeat breeding and even mastitis.
  • Humans may also get the disease from consumption of raw milk of infected animal or contact with uterine discharges.
  • The disease is very much prevalent in India, both in humans and animals.



  • Abortion occurs typically after 5th month of pregnancy.
  • In an infected animal, chances of abortion reduces with number of calvings.
  • No abortions may be observed after 4th calving, but dam and calf remain infected.
  • Placental retention may lead to infection and even death of the animal.


  • Vaccinate female calves (not male calves) between 4-8 months of age.
  • Only one vaccination is required in its lifetime to protect it from brucellosis.
  • Any abortion from 5th month onwards should be suspected for brucellosis.
  • Ideally infected animals should be culled. If culling is not possible, isolate the animal immediately for a minimum of 20 days after calving/abortion.
  • The aborted foetus, placenta, contaminated bedding, feed etc, should be buried (at least 4 feet deep) after a liberal sprinkling of lime. These materials contain very high bacterial loads and if disposed improperly cause the spread of disease by contami­nating food sources (pasture, feed, water etc).
  • Disinfect the shed after isolating the aborted animal.
  • When the animal is in isolation, disinfect the lochial discharges (which also contain high bacterial loads) daily with 1-2% NaOH or 5% sodium hypochlorite (bleach) so­lution till the discharges cease (usually by 10 –15 days).
  • Do not handle infected material with bare hands since the disease is zoonotic.



  • There is no effective treatment once the animal is infected since the bacteria re­mains in the body of the animal. Consult a veterinarian in case of suspicion.
  • Disease in humans is curable provided proper regimen is followed.


                           Vaccinate 4-8 month old female calves once -protect them for life.