Although it is only February and the breeding season seems a long way away, many farmers will already have selected some sires for use on their herds this year.

Many farmers use the economic breeding index (EBI) as a tool to monitor improvements in their herds. Other farmers will use breeding tools such as aAa.

The introduction and use of EBI within the Irish dairy sector has been extremely successful, with the breeding of more profitable, environmentally friendly and healthy cows.

Since its introduction, year-on-year there have been improvements made within the national herd and on many farms.

Breeding season

The breeding season is where the future generations of your dairy herd comes from and matching the correct sires to dams is important.

The selection of the correct sires allows for continued progression of your herd, including improved fertility, production and health.

The dam also plays a major role in the offspring that will be produced.

A heifer, from a heifer

As the national herd stabilises the need for replacement heifers will reduce, so breeding the best heifer you can should be the aim.

When selecting sires this year you should aim to generate the majority of your replacements from your bulling heifers.

Your bulling heifers should be the best genetics on your farm that are suitable for breeding. Obtaining a heifer, from a heifer, will accelerate the genetic gains quicker within your herd.

Of course, there will be excellent cows within the herd that you want to get a heifer from, but they should not be the first port of call. Instead you should target that heifer for breeding.

On many farms an easy-calving Angus bull is used just to get heifers milking, but if you select your sires correctly, using a dairy sire should not lead to increased calving difficultly.

If you have 20 heifers and use conventional semen you should obtain ten heifer calves. These heifer calves are more than likely the highest EBI animals on the farm.

Waiting until a heifer is almost two-and-a-half years old before breeding her to dairy artificial insemination (AI), has no major benefit and just delays the progression of your herd.

That is not to say there isn’t a risk associated with generating the majority of your replacements from your heifers, but the rewards should outweigh the risks.


The future use of sexed semen on farms will also help to accelerate this further as less dairy straws will be required to generate the same number of heifers.

Some farms have already begun using sexed semen and have been quite successful, so long as it has been used correctly.

But for now, when you are selecting bulls and discussing your decision with your AI company’s breeding advisor, target your heifers.

This will help you to produce the most profitable and environmentally friendly animals possible.