Postpartum uterine infection and endometritis in dairy cattle

After parturition, uterine involution, regeneration of the endometrium, return of ovarian cyclic activity, and the control of pathogenic bacteria in the uterus is required before cows are likely to conceive again. However, pathogenic bacteria often cause uterine disease in modern dairy cattle, leading to decreased productivity and reduced fertility. This review aims to provide an overview of postpartum uterine infection and disease in dairy cattle. Metritis and endometritis are the main postpartum clinical conditions; although, subclinical endometritis is an emerging issue. Postpartum uterine disease is associated with the isolation of Escherichia coli, Trueperella pyogenes, and anaerobic pathogenic bacteria. Sensing of bacteria or their pathogen-associated molecules, such as lipopolysaccharide, by the innate immune system generates inflammatory responses. Endometrial inflammation includes increased expression of complement, calgranulins, interleukins and acute phase proteins, as well as the chemotaxis of neutrophils and macrophages to the site of infection. Uterine disease is also characterised by tissue damage, including endometrial cytolysis caused by the cholesterol-dependent cytolysin, pyolysin. The responses to pathogens are energetically expensive, and depletion of the key cellular nutrients, glucose or glutamine, impairs inflammatory responses by endometrial tissues. For sustainable intensification of the dairy industry over the next 50 years, it is vital to understand why high-milk-yield cows are so susceptible to uterine pathology and develop new ways to prevent uterine disease.

Postpartum uterine infection and endometritis in dairy cattle

After parturition, uterine involution, regeneration of the endometrium, return of ovarian cyclic activity, and the control of pathogenic bacteria in the uterus is required before cows are likely to conceive again. However, pathogenic bacteria often cause uterine disease in modern dairy cattle, leading to decreased productivity and reduced fertility. This review aims to provide an overview of postpartum uterine infection and disease in dairy cattle. Metritis and endometritis are the main postpartum clinical conditions; although, subclinical endometritis is an emerging issue. Postpartum uterine disease is associated with the isolation of Escherichia coli, Trueperella pyogenes, and anaerobic pathogenic bacteria. Sensing of bacteria or their pathogen-associated molecules, such as lipopolysaccharide, by the innate immune system generates inflammatory responses. Endometrial inflammation includes increased expression of complement, calgranulins, interleukins and acute phase proteins, as well as the chemotaxis of neutrophils and macrophages to the site of infection. Uterine disease is also characterised by tissue damage, including endometrial cytolysis caused by the cholesterol-dependent cytolysin, pyolysin. The responses to pathogens are energetically expensive, and depletion of the key cellular nutrients, glucose or glutamine, impairs inflammatory responses by endometrial tissues. For sustainable intensification of the dairy industry over the next 50 years, it is vital to understand why high-milk-yield cows are so susceptible to uterine pathology and develop new ways to prevent uterine disease.(AU)