Management of the transition period: hormone therapy

The influence of mare numbers, ejaculation frequency and month on the fertility of Thoroughbred stallions

“…The comparable survey for Kentucky reported that 14.4% of mated cycles occurred in February [3]. No doubt this increase in February matings stems from the improved ability to hasten the onset of oestrus and ovulation in mares exhibiting seasonal and lactation‐related anoestrus by the application of various light regimes and/or hormone therapies (see [17,18] for reviews) and, hence, also affects the number of mares presented for covering later in the season, as discussed above. Furthermore, compression of the traditional breeding season in the UK, while stemming primarily from the breeders' desire to produce early foals, may also result to some extent from curtailment of a stallion's mating programme before July so that he can undergo quarantine prior to undertaking stud duties in the southern hemisphere.…”