1Department of Veterinary Physiology, University of Agricultural Sciences, Hebbal, Bangalore-560 024, India.
2National Institute of Animal Nutrition and Physiology, Bangalore-560 030.
3National Dairy Research Institute, Karnal, Haryana-132 001.
Production of embryos in vitro (in vitro Fertilization technology) provides an excellent and cheap source of embryos for carrying out basic research on developmental physiology, farm animal breeding and for commercial application of the emerging biotechniques like cloning and transgenic livestock production. Embryos of high genetic quality can be obtained from oocytes collected from slaughtered house ovaries or from donors of high genetic quality by ultrasound guided follicular aspiration. Despite technological progress in the last two decades, the practical application of in fertilization technology (IVF) is still less than anticipated because of low efficiency and high cost. Recent data indicate high rate of meiotic maturation (> 85% in cattle, >80% in buffalo), fertilization (> 80% in cattle, >70% in buffalo) and cleavage (> 70% in cattle, >50% in buffalo) but low rates of blastocyst formation (~ 30% in cattle, ~25% in buffalo) and calf production (~10%) and some with severe anomalies. The efficiency of in vitroembryo production (IVP) in buffalo is much lower than in cattle. Substantial improvements in culture systems are needed and many physical, biochemical, molecular, immunological factors affecting the development of oocytes and embryos remain to be investigated before in vitroembryo production can be acceptable. The optimization of IVP of embryos and the analysis of the related problems are the major challenges to be addressed.
