Fertilization failure and early embryonic mortality as a major cause of reproductive failure in cattle: A review

Reproductive failure in lactating dairy cows is a significant limitation to the dairy industry. Fertilization failure, Embryonic or fetal losses are major contributors to that limitation. The objective of this review was to determine cause of fertilization failure and early embryonic mortality in cattle. Fertilization failure and embryo mortality is a major cause of economic loss in dairy production systems. Direct effects of fertilization failure and embryo mortality are reflected in reduced conception rates with consequent effects on efficiency, production and profitability. Embryonic loss can be early or late .The major component of embryo loss occurs before day 16 following breeding with emerging evidence of greater losses before day 8 in high producing dairy cows. Late embryo loss causes serious economic losses because it is often recognized too late to rebreed females. Various factors can be a cause for fertilization failure and embryonic mortality. The major cause includes genetic, environmental, endocrine, infectious nutritional factors. More balanced breeding strategies with greater emphasis on fertility, feed intake and energy must be developed. There is a range of easily adoptable management factors that can either directly increase in embryo survival or ameliorate the consequences of low embryo survival rates. The correction of minor deficits in several areas can have a substantial overall effect on herd reproductive performance.