Scanning results from the farm this week show sexed semen can work and achieve conception rates as good as conventional "unsorted" semen. Earlier this year, 98 cows on the Greenfield Farm were selected as suitable cows for a fixed time AI trial comparing sexed semen to ordinary unsexed semen.

Three trial subgroups were created: fixed-timed AI using sexed semen at 9am (early insemination); fixed-timed AI using sexed semen at 3pm (later insemination); and conventional semen.

The thinking behind the trial, led by Stephen Butler, was that the timing of insemination with sexed semen is crucial. Sexed semen doesn’t survive as long as conventional semen in the reproductive tract. Hence, two different timings for the sexed product were on the trial.

The results from this herd showed a 53% conception rate to the sexed product at 3pm (ie later insemination post-heat onset), 53% for conventional semen and then 47% conception rate for the 9am (early insemination).

Remember of course that only a subset of the herd on the Greenfield farm was involved and this is one of 24 farms (approx 3,000 cows) involved in the Teagasc Moorepark sexed semen trial. On Thursday this week, the 98 cows that were part of the trial were scanned. The results look positive for sexed semen but, again, it will be interesting to follow the rest of the results as they come in. The cows were scanned in advance of breeding start to ensure they were clean internally and assessed for condition score, etc.

The herd continues to milk well at 2.1 kg of milk solids. They are on 5kg of nuts as grass is scarce (128kg/cow).

Farm manager David Fogarty finished up with the Greenfield Farm on Friday. David started with the farm in early May last year and his professional conduct and experience steered the farm through the drought and intensive feeding period which has set the farm up for the excellent results being achieved at the moment. We wish him well on his travels. Like previous managers, the farm's loss is the industry's gain.

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