Endometritis impairs luteal development, function, and nitric oxide and ascorbic acid concentrations in buffalo (Bubalus bubalis)

A vast majority of the world buffalo resource is concentrated in tropical and subtropical countries. Apart from heat stress and poor nutritional availability, endometritis is one of the most commonly encountered reproductive problems limiting fertility and consequently productive potential of the species. As demonstrated recently, endometritis impairs growth and follicular fluid composition of the largest follicle in buffalo. In the present study, the effect of endometritis on luteal development, function, nitric oxide (NO), and ascorbic acid was investigated. Reproductive tracts were collected from 90 cyclic buffaloes at an abattoir and grouped into endometritic (n = 36) or non-endometritic (n = 54) buffaloes based on physical examination of uterine mucus, white side test, and uterine cytology. Samples with pus-containing mucus, positive reaction on white side test, and/or > 5 % neutrophils were considered to be positive for endometritis. Corpora lutea were enucleated, weighed, classified into stages I to IV, and assayed for progesterone (P-4), NO, and ascorbic acid concentrations. Endometritic buffaloes had lesser (P < 0.0001) luteal weight and P-4, NO, and ascorbic acid concentrations than non-endometritic buffaloes. The findings indicated that endometritis impairs corpus luteum development and function in buffalo. Reduced luteal NO and ascorbic acid concentrations during endometritis are novel findings.