RETENÇÃO DE PLACENTA EM BOVINOS DE LEITE: UMA REVISÃO

Abstract

Retained placenta is one of the main problems in dairy cattle and is highly relevant, given its influence on the animal's productive parameters. The aim of this study is to investigate, through a literature review, how retained placenta can influence the productivity of dairy cattle. The placenta is a maternal-fetal tissue whose function is to ensure the safety and maintenance of the fetus during most of pregnancy. Placental separation is characterized by a loss of connection between the fetal and maternal components of the placenta, which, together with the uterine contractility triggered by parturition, results in the expulsion of the fetal membranes. The release of the placenta occurs through the loss of the fetal membranes' connection to the uterus, and this process is only possible after placental maturation, which occurs on average between 3 and 5 days before delivery. Placental retention (PR) is the second most common puerperal disorder in cattle and is defined by the persistence of the placenta in the female reproductive tract after 12 to 24 hours postpartum. When left untreated, PR can result in septic metritis, anorexia, depression, hyperthermia and decreased production, with cases of hypogalaxia and agalaxia being reported. Some factors can directly contribute to RP, such as stress, management errors, nutritional deficiencies and metabolic diseases, among others. In addition to causing various reproductive problems, PR also influences a decline in the animal's milk production. PR can cause serious damage to dairy farming.