Dairy farmers should be making plans to ensure they have sufficient bull power on hand this season. Last year at pregnancy testing we identified properties where high empty rates were related to insufficient bull power. (Either from a simple lack of bulls or a high rate of bull failure).
As a very minimum you require 1 sound, mature bull for every 30 empty cows you expect to have at the end of AI. You can obviously reduce bull requirements by extending AI programmes. It is also necessary to be confident about the conception rates you are likely to achieve.
We would urge caution whenever yearling bulls are considered. They must be well grown and we would advise
checking semen quality to ensure they are sufficiently mature. On occasions when testing yearlings we find high numbers that have poor fertility, generally due to being under grown or too young.
Remember when purchasing bulls they should be:
BVD blood tested clear
EBL blood tested clear
Fully BVD vaccinated (ie 2 vaccinations 4 weeks apart)
Fully lepto vaccinated (ie 2 vaccinations 4 weeks apart)
And remember to BVD and lepto older bulls you may have on hand.