Early pregnancy in the mare: information to interpret, concepts to accrue

Abstract

Knowledge of how the mare and her conceptus have to interact during their first month together if pregnancy is to be maintained is growing rapidly. That growth is owed to enormous advances in genomic and proteomic technology coupled to the need to combat the economically important problem of early embryonic loss. The first part of this presentation will describe and discuss some of our recent findings on how certain proteins and cytokines change at the interface between the mare and her conceptus; these we have studied in biopsy samples of endometrium, the uterine environment (as reflected in flush fluid), and three components of the conceptus (the capsule and the bi- and trilaminar yolk-sac wall) before and after conceptus fixation, and in response to experimental treatment of the mare with the prostaglandin (PG) cloprostenol to induce luteolysis and embryonic death. Proteomic profiles of flush and yolk-sac fluids and of capsule-associated proteins were established from trypsin digested peptides by LC MS/MS with Scaffold-2 interpretation, or by SDS-PAGE and immunoblots. Transcriptomes for endometrium and trilaminar trophoblast were determined by Agilent 44K expression microarrays.