The infectious disease epidemiologic triangle of bovine uterine diseases
Machado, V. SBicalho, R. C
Postpartum uterine diseases are important for animal welfare and economic reasons, causing cow discomfort, elimination from the herd and impaired reproductive performance. Metritis is characterized as an abnormally enlarged uterus and a fetid, watery, red-brown uterine discharge within 21 days after parturition. Endometritis is defined as inflammation of the endometrium after 21 days postpartum without systemic signs of illness, and can be considered the chronic stage of uterine inflammation. It has been reported that the metritis affects 10 to 20% of cows, and endometritis affects 5.3 to 52.6% of cows. Metritis affects the cow systemically, and has a negative impact on milk production and reproductive performance. Cows affected with endometritis are not systemically ill, and do not have their milk production altered; however, they have impaired reproductive performance. Metritis and endometritis are complex multifactorial diseases, and a wide range of factors contributes to their occurrence. They are often associated with mixed bacterial infection of the uterus, and the major pathogens associated with uterine diseases are Escherichia coli, Trueperella pyogenes and Fusobacterium necrophorum. Events during the transition period related to negative energy balance and metabolic imbalance, mineral deficiencies, leading to immunosuppression are of great important during establishment of intrauterine bacterial infections. This, combined with endometrium trauma events during parturition (such as calving related problems), and environmental factors (poor hygiene at calving, housing type and calving season), increases the risk of metritis and endometritis.(AU)
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