Pathogenesis of uterine diseases in dairy cattle and implications for fertility

Abstract

Uterine diseases in cattle occur at all stages of the reproduction cycle but the majority of cases is found in the postpartum period. The inflammation of the uterus is generally defined as metritis or endometritis, with several graduations, e.g. puerperal metritis, clinical metritis, clinical or subclinical endometritis. Whether uterine diseases have a negligible, moderate or detrimental effect on fertility is still under discussion and depends on definitions and classification. In the past, it was assumed that the pregnant uterus is free of pathogens, but recent studies found several species including pathogens in the uterus and endometrium of pregnant cows. After parturition, a broad diversity of bacteria with >200 different species has been found in the early postpartum period. Not all of these bacteria, however, are considered as pathogens. Furthermore, bacteriological findings provide only evidence for infection but not for inflammation. For some bacteria, particularly Escherichia coli and Trueperella pyogenes pathogenic mechanism resulting in metritis and endometritis have been elucidated in detail. The role of bacteria that can be regarded as opportunistic or potential pathogens, e.g. Bacillus pumilus, is still under investigation. The understanding of the uterine microbiota and its interactions is increasing with the use of modern high-resolution techniques such as Fouriertransform infrared spectroscopy. Endometrial cytology provides additional information about alterations in the endometrium. Knowledge of innate uterine defense mechanism in cattle has increased a lot in the recent past. It can be speculated that improving or modulating uterine defense mechanism will be part of future prevention and treatment approaches beyond the use of antimicrobials. In this context, cellular and molecular defense mechanisms have been in the focus of interest, e.g. the role of interleukins or mucins. This review gives a short overview on some aspects of recent research on uterine diseases in cattle.

Update of the list of QPS‐recommended biological agents intentionally added to food or feed as notified to EFSA 11: suitability of taxonomic units notified to EFSA until September 2019

“…The analysis of their titles by two experts left 15 articles for the title/abstract phase, and from these nine articles passed to the full text phase for further analysis. Three papers (Harwood et al., ; Jezewska‐Frackowiak et al., , Drillich and Wagener, ) were not dealing with safety concerns. Three papers have serious methodological problems in relation to strain identification and source attribution (Joshi et al., ; Shah et al., ) and are not food related (Aydin et al., ).…”

Biofilm forming potentiality of Escherichia coli isolated from bovine endometritis and their antibiotic resistance profiles

“…Endometritis is known to be one of the major diseases, which upset the reproductive performance of cattle and reduce livestock productivity [ 1 ]. Following parturition, the invasion of the endometrium with different bacterial species (more than 200) occurs, but not all these bacteria considered as pathogens [ 2 ]. The initial step in developing bovine endometritis is the infection of the endometrium with Escherichia coli preceded by further bacteria such as Arcanobacterium pyogenes [ 3 ].…”

Isolation, Identification and Antibiogram Pattern of Bacteria Associated with Postpartum Metritis in Dairy Cattle

“…Metritis is described as a uterine lining-wide inflammation. Septic puerperal metritis most frequently happens in the first 10 to 14 days following parturition in dairy cattle [1]. It costs farmers a lot of money, especially when it happens to multiparous dairy cattle, because it lowers reproductive performance due to delayed uterine involution, more open days and fewer services per conception [2][3][4].…”