Impact of nutritional stress on early embryonic survival.

Abstract

Low reproductive efficiency is the utmostcritical predicamentfaced by the modern livestock industry across the globe. Early embryonic loss is one of the major causesof poor reproductive efficiency resulting in delayed pregnancy, fewer calves born, reduced milk production, slower genetic progression,and substantial financial loss to the beef and/or dairy industry. The establishment of pregnancy results from the interaction between the embryo and the dam and is the culmination of a series of events initiated with development of the follicle and gametes. Among numerous internal and external factors,nutrition has the potentialto alter the microenvironmentof the oocyte and the embryo, making it more hostileto optimal fertilization and pre-implantation embryonic growth. Understanding the impact of nutritional stress on oocyte function, embryo development and reciprocal signaling networks between the embryo and uterus will lead to alleviation of the problems associated withearly embryonic mortality.