Superovulation protocols for dairy cows bred with SexedULTRA™ sex-sorted semen.

The objective was to compare embryo yield and quality in lactating dairy cows superovulated (SO) with varying amounts of gonadotropins and FSH:LH ratios and inseminated with SexedULTRA™ sex-sorted semen. The SO treatments (n = 77) involved 3 protocols: groups F700 and F1000 were given total doses of 700 and 1,000 IU of Folltropin (FSH:LH ratio 49:1), respectively, whereas group F700P300 was given 700 IU of Folltropin + 300 IU of Pluset (FSH:LH ratio 1:1). Cows were artificially inseminated 3 times over a 10-hr interval with frozen-thawed SexedULTRA™ sex-sorted semen (total of 10 × 10 sex-sorted sperm), starting 18 hr after onset of oestrus, with embryos/ova recovered 7 d after oestrus.