Waikato DairyNZ Farmwatch for week ending October 13

Bull numbers and management are critical for good mating results. Photo / DairyNZ

Waikato farm data for the week ending Friday, October 13.

COMMENT

By DairyNZ

Most farms will have bulls sorted to tail off the herd in the next few weeks.

Bull numbers and management are critical for good mating results.

Bulls can introduce several diseases to the herd such as TB, lepto, BVD, pink eye, M. bovis or a venereal disease.

Check the health status of the bulls and keep NAIT records up to date.

Sexual athlete or three-hit wonder? If bulls are overworked (not enough bulls or not rested) fertility will drop.

Aim for one working bull per 30 not-in-calf cows, plus at least the same number of bulls resting.

Swap the bulls every 1-2 days.

A rested bull will use up about 90 per cent of his sperm in the first three ejaculates and the likelihood of fertilisation drops 5 per cent for every subsequent ejaculate.

Farmwatch graphic / DairyNZ

Ensure staff are trained and confident with working with bulls.

Regularly observe bulls serving to ensure they are serving correctly.

Immediately remove and replace bulls that are unable to serve properly or are sick or injured.

A bull with an elevated temperature can have his fertility reduced for 60 days after it is treated.

For more information on mating season and bull management visit - Bull Management - DairyNZ.