Fetal Disease and Abortion: Diagnosis and Causes

Reproductive failure is a significant problem in breeding management that arises from physiological, anatomical, inherited, and infectious causes. This chapter focuses on fetal death and the approach to diagnosis, including some aspects of embryonic death, congenital abnormalities, and common gross findings. A brief overview of anatomy and development are included to familiarize the reader with general concepts. The investigation of abortion is a vital part of herd management and its importance is hard to overemphasize. Gross lesions of the fetus are generally uncommonly noticed. They may be inapparent for four reasons: the fetal immune system is not of sufficient robustness to mount a response that is easily observed at the gross level; fetuses often die before lesions appear; lesions are masked by autolysis; and fetal pathology may manifest itself in ways that are difficult to recognize. It is important to recognize that infection of the conceptus does not necessarily lead to fetal death.