Moorepark held a fertility event at the Kilworth Research farm last week. There were plenty of questions asked; we highlight some of the best.

Andrew Cromie, ICBF, and Stephen Butler, Moorepark, both members of the sexed semen board, showed a graphic of conception rates for four bulls used last year in the sexed semen trial. The results showed a conception rate of between 50% and 60% for three of the bulls but a conception rate closer to 20% for the fourth. The questions from the farmers were: (1) Why was that poor fertility bull allowed out to farmers? (2) How did he pass the quality tests?

Answer: Andrew and Stephen emphasised that, despite rigorous testing in the laboratory when the semen was taken and testing after the sexing process was completed, the laboratory technicians did not pick up anything to say that the particular bull in question would have lower conception rates. The researchers had no specific answer as to why he had lower conception rates across all treatments and finding an answer will form part of the further research required once a sexed semen laboratory is established in Ireland.

That particular bull is no longer in use and Andrew and Stephen emphasised that it highlights a team of six or eight bulls is necessary because if you had a lot of the poor fertility bull used in your herd, the results would be a complete disaster.

At the board on fertility management, one of the most popular questions was how to treat a late-calving or non-cycling cow and whether it was worth going to the effort of using drugs to try to get them cycling and in calf.

Answer: The American researcher Matt Lucey and the Irish scientists suggested it was worth going to the effort for a proportion of the herd because if they are late-calving, then they need a kickstart and while they might not go in calf after the first insemination, they will go in calf to maybe the second insemination.

The advice was for earlier treatment for those late-calving or non-cycling cows rather than intervention when it was too late. (See a detail response on why and what to do with this subset of your herd on page 30 and 31 this week.)

On the board discussing future breeding options, the question from farmers was whether the EBI index is breeding enough milk into cows and if too much emphasis on fertility will reduce milk yield per cow when quotas are eliminated. Farmers argued that you need volume to carry the milk fat and protein and asked if many of the bulls available are too low in volume.

In answer to this query, Donagh Berry said countries where quota has never limited production, like the US and New Zealand, are now following higher fertility breeding indexes similar to Ireland as dairy farmers strive to improve the health and fertility of dairy cows. He explained the advice for breeding in a post-quota Ireland will be the same as that delivered over the last 10 years while milk quota limited production on farms. The key message is better fertility is delivering more milk profitability than breeding for milk alone.

Donagh was adamant that the EBI in its current shape will deliver the most profitable cow for all systems post-2015. He highlighted that the EBI has more emphasis for milk production than both the US and Dutch breeding indexes. He also highlighted herd health as the trait with next importance.

He said: “If we continue the same trends in genetic gain with the EBI, then fertility will no longer be a problem by 2025 and herd health traits will be the next selection trait that farmers need to focus on.”

Next-generation herd

The next-generation herd was the key attraction on display at the Kilworth research farm. There is an elite herd (top 1% on EBI) and a national average herd (Nat avg EBI) on trial. Both herds are on feeding system trials. Over 90% of the elite herd were calved in six weeks versus 80% calved for the national average herd. It’s early days yet for a trial like this but the economics on the results will be very interesting.