Pregnancy rate of Bali Cows following Artificial Insemination using Chilled Sexed Sperm under Intensive Management in Tropical Area

Abstract

Application of sexed sperm either in the form of chilled semen or frozen semen in artificial insemination of cattle is commonly used to produce the desired sex of offspring.  In this study, 20 bali cows were used to evaluate the success rate of artificial insemination using chilled sexed sperm of bali cattle to induce pregnancy. All cows were kept in individual pens under intensive management with environmental temperature 30 to 32^oC and fed native grass ad lib plus 1.5 kg rice bran per cow per day. Semen was collected from bali bull and sperm sexing using albumin column method was performed to produce sexed sperm. All cows were performed estrus synchronization using PGF2α and artificial insemination was applied on day 3 after synchronization. Estrus detection was performed on day 2-3 following synchronization to evaluate the estrus percentage and estrus quality. Whereas pregnancy rate was determined on two occasions during sixty days following application of artificial insemination. Twenty one days after artificial insemination, pregnancy was judged by non return rate, while on day 60s following artificial insemination, the pregnancy was determined using rectal palpation methods.  The results showed that only one cow (5%) showed sign of estrus again on day 21 after application of artificial insemination, while 19 cows (95%) did not show sign of estrus which expressed the early sign of pregnancy. However, on day the 60s after application of artificial insemination only 11 cows (55%) were predicted pregnant following rectal palpation. In conclusion, PGF2α could promote estrus sign with good percentage and quality while chilled sexed sperm of bali cattle could induce pregnancy with fairly success rates.