Aspectos da fisiologia da placenta nos animais domésticos e retenção de placenta nos bovinos - revisão de literatura.

Abstract

The placenta is an organ of great importance in mammalian reproduction to exercise several functions, among which the most important is the maintenance of pregnancy. Therefore, this body is quite complex and of such importance. The existing placenta complexity is due to their anatomy and physiology that are different according to species that have, due to their structures which are originated from interaction between maternal and fetal tissues. Four different membranous structures are involved in the development of the fetus system maternal placental mammals. They are: the corium, the amnion, the yolk sac and the allantois. There is a great variability of the fetal membranes, whose function is to classify the types of placental occurring in various mammalian species. This classification varies according to the villi of the fetal corium and the crypt of the uterine lining, and then termed as adeciduade and deciduada as well as the distribution of the villi which are responsible for classifying as diffuse, cotiledonária, zonary and discoid. The objective of this work was to study the formation and the types of fetal membranes, as well as the placenta classification, according to the peculiar characteristics of each and placental retention, which is an existing problem in both farm animals and animals of Pets.