POST-PARTUM SUB-CLINICAL ENDOMETRITIS IN DAIRY COWS: INCIDENCE AND DIAGNOSIS

Post-partum uterine infections such as metritis, clinical endometritis and sub-clinical endometritis, are the most common cause for decreased productivity and fertility in dairy cows. Being the least severe form of endometritis, sub-clinical endometritis (SCE) is defined as the superficial inflammation of endometrium with no signs of systemic illness and characterized by an increase in number of polymorphonuclear cells (PMNCs) inside the uterine lumen. The impact of sub-clinical endometritis on fertility of dairy cows is well known probably due to absence of any clinical signs and thus, difficulty in diagnosis and treatment. Different techniques such as endometrial cytology, uterine biopsy, biochemical analysis of uterine fluid, and measurement of acute phase proteins and inflammatory markers have been employed for the diagnosis of SCE. Doppler and B-mode ultrasonography of middle uterine arteries and uterus have also been used to diagnose the inflammation via assessment of uterine perfusion, respectively. Among all methods, endometrial cytology via cytotape is one of the most advanced and frequently employed methods for diagnosis of cytological endometritis based on the fact that proportion of PMNCs increase during uterine inflammation. The review focuses mainly on current status of incidence and diagnosis of post-partum sub-clinical endometritis in dairy cows.