Dairy focus: Doubling cow numbers and gearing up for breeding in Co. Cork

Pat and Geraldine Ahern run a dairy enterprise on 28ha in Bridepark, Conna, Co. Cork. Over the past four years, they’ve doubled cow numbers on their farm and have moved from just under 40 to 77 cows.

A herd of predominately Holstein Friesian cows takes pride of place on the holding; however, four crossbred heifers are scattered among the milking herd.


Pat’s ‘black and white’ herd is delivering the goods in the bulk tank. Last year, the herd average stood at 9,000L/cow and 700kg/cow of milk solids. This level of output was achieved from a meal input of approximately 1t/cow and a spring-calving herd.

Along with managing the herd, Pat worked as an AI technician with Eurogene and, as a result, calving commenced relatively early in the year to allow Pat to balance his off-farm commitments.

Speaking at a recent LIC/Eurogene event on his farm, Pat explained: “We calve the cows relatively early in the year to have it completed before I get busy with AI.”

However, Pat intends to delay breeding by three weeks on the farm this spring to allow the herd to calve closer to grass. This will also open up an opportunity to reduce the concentrate input required. A new target of 750kg/cow has been set.

As it stands, the cows in the herd are currently producing 29L/day; but there’s six carryover cows from last year present and they’re bringing down the daily average.

When asked why he carried over cows, Pat said: “We’ve gone from 40 cows to nearly 80 cows over the last three-to-four years.

“Now we are more or less where we want to be and that’s why we had been recycling cows over the last while. It will finish this year.”


Calving commenced on January 6 and there’s just one cow left to calve. Pat’s stance on breeding is simple; he wants to breed the best cows to the best bulls. When it comes to identifying the best cows, milk recording is utilised.

With a herd EBI (Economic Breeding Index) of €151, a number of Holstein Friesian bull calves from Pat’s herd have been sold into AI. One cow family has proved particularly popular, as three generations have all held to the first service.

Prior to the commencement of breeding, Pat explained, scratch cards and tail paint are used to paint a picture of the herd’s submission rates.

This provided positive results during the 2017 breeding season, as 95% of the cows were submitted in the first three weeks. With the information gathered from the three-week period prior to breeding, Pat was able to identify any potential problem cows early and implement corrective measures if needed.

“I aim for a 550kg cow, but some of them are a little bit bigger than that. I hope to bring the herd size down in the coming years,” Pat added.

When it comes to sire selection, he said: “Recycled cows, cows with poor udders or high cell counts will get a beef bull.”

The final cows to be served will get short-gestation KiwiCross bulls to tighten up the calving spread.


LIC’s Joyce Voogt was on hand at the farm walk to offer Pat and other farmers some advice ahead of the breeding season.

Although Pat has grown his herd over recent years and has been carrying over cows, there’s an opportunity for him to get more selective when it comes to culling decisions.

“It’s all about getting the herd of cows you want to milk,” Joyce explained. “There’s the potential to put pressure on the female side by ranking you cows on the basis of milk recording results,” she said.

“High empty rates rob us of the choice of which cows to keep or cull. When it costs €1,300-1,500 to bring a heifer into a herd, we don’t want to be losing them too early,” she explained.

Pat Ahern pictured with Joyce Voogt and Linda O’Neill

For farmers carrying over recycled cows, she said: “I would recommend not keeping a heifer calf out a recycled cow because she’s probably one of the less fertile animals.”

On body condition score, she said: “One thing to remember is that body condition score at calving and body condition score at mating are very closely correlated.

We’re trying to calve our cows down at the target body condition score of 3.25 and that’s the first and most important target to hit.

“We don’t want to lose more than 0.25 of a body condition score between calving and breeding. Body condition score is so important because it’s a very strong driver of days to first heat. A cow that is thinner will take longer to have her first cycle post-calving,” she said.