Watch: Ensure sufficient bull power this breeding season

This year of all years, after the challenging spring we have had, the added work of continued heat detection when breeding is not appealing.

Sexed semen has reduced the demand for conventional dairy artificial insemination (AI) and the stock bull is being considered much earlier in the season to get the remainder of the herd in calf once the best cows have been chosen to breed replacements from AI.

The goal is to breed calves of value from every cow in the herd, whether they are replacement stock or dairy beef calves that are saleable next spring.

So, the stock bull chosen must have the genetic merit to produce the right calf.

More critical to the dairy enterprise is guaranteeing calving ease and short gestation so that the six-week calving rate is maintained, and cows get through calving safely and do not end up with production or breeding impacts due to calving difficulty.

Bull power for breeding

Choose your stock and AI bulls with high reliability for calving ease, particularly for maiden heifers.

Always check on any bull being offered for the number of records behind the calving proofs, as this dictates reliability.

There are ‘cheap’ bulls offered that look like good value on the day but have little or no records to support proven calving ease.

There are practical considerations when introducing bulls into a herd when only 50% of the herd may be in calf.

The first risk is overwork. A mature bull can serve three cows in two days and a young bull can serve three cows in four days.

The general rule of thumb is one young bull to 10 empty females and one mature bull to 20-30 empty females.

Remember that in large herds, bulls take time to adapt and find their way so there may be a lull in calving the following year after their introduction.

Also, the gestation length of these bulls may be longer than the top AI sires that are specifically selected for short gestation, and calving will slow down the following year.

So, when introducing a stock bull to the herd, inseminate for the first 10 to 14 days of the bull being released and each day where there are two or more cows on heat per bull.

This allows the bull to adapt and catch up, or use AI until you are certain that the number of potentially empty cows in the herd matches the capability of the number and age of the introduced bulls.

Have some spare capacity if one gets lame or injured. If a bull shows any sign of lameness or being off form, get them out of the system immediately and revert to AI or bring in a sub.

Short gestation, low calving difficulty, AI dairy beef bulls with high carcass weight breeding values, produce saleable calves at low cost and should be used either exclusively or as an adjunct to stock bulls to secure calving for 2025.

The Dairy Beef panels that you will find in the Munster Bovine catalogues are sires that have been proven in the dairy herd.

There is a considerable amount of data available on these highly reliable sires, and Munster Bovine can be sure how these sires will perform on their customer’s dairy herd.

Herdowners can be assured of the following when using beef sires for the dairy herd from Ireland’s largest dairy beef programme: