Dinoprost 14-day oestrus synchronisation schedule for dairy cows.

Oestrus and ovulation were synchronised in 82 lactating Friesian dairy cows with two injections of dinoprost, and the cows were inseminated 72 and 96 hours after the second injection. Twenty-one of the 41 cows (51 per cent) which had a 14-day interval between the dinoprost injections conceived to the inseminations, compared with 18 of the 41 cows (44 per cent) which had an 11-day interval between the injections.