Main description:

Reproductive wastage is a major inefficiency in all livestock production with embryonic mortality accounting for a major portion of this loss. Accordingly the Commission of the European Communities encouraged the organisation of a seminar on embryonic mortality in farm animals which was held in Brussels on the 11th and 12th of December 1984. This book contains the text of the papers, discussions and final summary presented at that Seminar. As a background to the Seminar, the extent and timing of embryonic loss was described for farm animals. Particular consideration was then given to the various mechanisms and signals, both embryonic and uterine in origin, that are so far known to be involved in the establishment of pregnancy. Possible causes of embryonic death including physiological, endocrinological, genetic and immunological components were outlined and discussed. The final summary contains general conclusions from the Seminar and recommendations for future research work on this topic. J.M. Sreenan M.G. Diskin July 1985. ******************** THE EXTENT AND TIMING OF EMBRYONIC MORTALITY IN THE COW J. M. Sreenan & M. G. Diskin, The Agricultural Institute, Belclare, Tuam, Galway, Ireland ABSTRACT The extent and timing of embryonic mortality in heifers, normal cows and repeat breeder cows has been reviewed.

Contents:

Session 1: The Extent and Timing of Embryo Loss in Farm Animals.- The extent and timing of embryonic mortality in cattle.- Timing and extent of embryonic mortality in pigs, sheep and goats: Genetic Variability.- Discussion.- Session 2: The Establishment of Pregnancy.- Molecular and cellular signalling and embryonic survival.- Early pregnancy factor: It's significance as an indicator of fertilisation and embryonic mortality..- Uterine environment in early pregnancy.- Accumulation of sex steroids in preimplantation pig blastocysts and their importance for an undisturbed early embryonic development.- Periovulatory hormone profiles in relation to embryonic development and mortality in pigs.- Discussion.- Session 3: Progesterone and Embryo Loss.- The influence of progesterone profile on embryo loss in ewes.- Progesterone and embryo survival in the cow.- Pregnancy diagnosis and embryonic mortality in the cow.- Discussion.- Session 4: Genetic and Environmental Factors and Embryo Loss.- Embryonic mortality in steroid immunized sheep.- Embryo loss following embryo transfer in cattle and swine.- The role of the male in embryonic mortality (cattle and sheep).- Genetic constitution of early stage pig embryos and embryo mortality.- Cytological parameters for rating bovine embryo quality.- Embryonic losses and the role of nutrition: Statistical considerations.- Nutrition and embryo loss in farm animals.- Uterine pathogens and embryonic mortality.- Porcine embryo and fetal loss related to infection.- Discussion.- General Conclusions and Outlook.- General Conclusions and Outlook.- List of Participants.