Production of high quality Philippine dairy-type cattle through reproductive biotechniques

Three studies were conducted to produce high quality Philippine dairy-type animals through the use of embryo transfer and cryopreservation techniques. The productive as well as the reproductive performance of the offsprings were also evaluated. In the first study, the superovulation response of Holstein Freesian (HF) and HF-Sahiwal (SW) crosses to ovine follicle stimulating hormone (o-FSH) and subsequent embryo recovery were compared. Only 50% of HF and HF-SW donor cows responded to o-FSH. The mean number of ovulation for the HF donor was 5 compared to 10 for HF-SW donors. No significant difference was observed on the number of embryos recovered for the two groups. However, the mean number of normal embryos was significantly higher in HF-SW donors than with HF donors. Nine embryos were transfered to recipients resulting in four pregnancies and to live births. Eight embryos were vitrified and two were subsequently transfered to recipients, resulting in one pregnancy and live birth. In the second study, peocine follicle stimulating hormone (p-FSH) was used to superovulate 22 donor cows utilizing two methods of administration. Nine of eleven donors responded to p-FSH administered in decreasing doses while 10 of 11 donors responded to p-FSH given in constant doses. Although donors given constant doses of p-FSH yielded more corpora lutea (ovulation) embryos and normal embryos, than donors treated with decreasing doses of p-FSH, significant difference was not observed. Twenty six normal embryos were transfered to estrus-synchronized recipients resulting in 17 pregnancies and 15 live births. Seventy-five normal embryos were vitrified. Twenty vitrified embryos were subsequently warmed and transfered to recipients resulting in 10 pregnancies and eight live births. In the third study, the cost to produce one embryo transfer (ET) calf was determined. It costs P3,482.90 to produce one transferable embryo and P15,173.90 to produce one ET calf. Twenty-five calves born from the transfer of 17 fresh embryos and vitrified embryos were evaluated for their productive and reproductive performance. Birth, weaning and yearling weights of ET calves were heavier than non-ET calves born over the same period. However, only the weaning weight of ET calves was significantly heavier than non-ET calves. Female ET offsprings were bred earlier at 19.6 months of age compared to 22 months for non-ET offsprings. However, the average number of service per conception (1.43) for the two groups was the same. One ET offspring gave birth to a female calf at 30 months of age and produced an average of 11.0 liters per day for 135 lactation days.