Ask the Vet

Reintroduce Bulls Slowly After Breeding Season

Bulls develop a social order that is always being challenged. (DTN/Progressive Farmer file photo by Victoria G. Myers)


We run 200 to 250 head of cows, sorted into groups of 50 head. We run two bulls per herd. When breeding season is over, we pull out the bulls. We always have lots of fighting between bulls. This year, we lost a bull after he tore up a knee fighting. Do you have suggestions on how to minimize fighting and injury?


Even if the same bulls were together before breeding season, there will be fighting when they are reintroduced. Bulls develop a social order that is always being challenged. When reintroducing bulls, never mix them in a small area, especially not on concrete. This can be extremely dangerous to bulls and to humans.

A pasture should be large enough for bulls to fight without getting into fences, buildings, equipment or other dangerous objects. The loser should have a place to escape. One report suggests at least 2 acres per bull to reduce fighting and injuries.

Spread out feeding areas, water and shade. Keeping bulls in adjacent pens separated by an electric fence with at least 4,000 volts for several days may help acclimate bulls before mixing them. Feeding them during introduction may distract some bulls from fighting.

Mixing mature and small bulls together first, then blending groups may also help. Putting just one new bull into a group should be avoided. Instead, pair a new bull with another first, then gradually add both to a small, and then a bigger, group. I would appreciate hearing from others on how they handle this issue.


Editor's Note:

Please contact your veterinarian with questions pertaining to the health of your herd or other animals. Every operation is unique, and the information in this column does not pertain to all situations. This is not intended as medical advice but is purely for informational purposes.

Write Dr. Ken McMillan at Ask the Vet, 2204 Lakeshore Dr., Suite 415, Birmingham, AL 35209, or email