Mastitis outcomes on pre-ovulatory follicle diameter, estradiol concentrations, subsequent luteal profiles and conception rate in Buffaloes

•Mastitis disrupts the functioning of the mean diameter of pre-ovulatory follicle.•Mastitis lowered plasma estradiol concentration on the day of estrus.•Mastitis has a multiple actions that hinder corpus luteum development and function.•Mastitis decreased pregnancy consequence of buffaloes.

The objectives of this study was to investigate the outcome of mastitis, in its clinical or subclinical forms, on the mean diameter of pre-ovulatory follicle (POF), plasma estradiol concentration on the day of estrus, subsequent luteal profile and subsequent conception rate in buffaloes. Sixty dairy buffalo (Bubalus bubalus) conducted in this study were divided into three groups {healthy (H), n = 20; subclinical mastitis (SCM), n = 18; and clinical mastitis (CM), n = 22}. Ultrasonography of ovaries revealed that mean diameter of POF was larger (P < 0.05) in H buffalo (14.35 mm) compared to SCM (12.40 mm) and CM (10.25 mm). Also, plasma estradiol concentration on the day of estrus was higher (P < 0.05) in H buffalo compared to SCM and CM counterparts; 34.95 vs. 32.87 and 27.50 pg/ml, respectively. Besides, positive correlation was observed between the POF diameter with plasma estradiol concentration in H, SCM and CM buffaloes (r = 0.64, 0.74, 0.72 respectively, P < 0.05). Moreover, positive correlations (P < 0.01) were found on days 9, 12, 16, and 21 post-ovulation between POF diameter and luteal profile. Thus, the conception rate in H buffalo was higher (P < 0.05) compared with SCM and CM counterparts; 55% vs. 38.89 and 18.18%, respectively. In conclusion, mastitis in its clinical or subclinical forms disrupts the functioning of the pre-ovulatory follicle on the day of estrus, associated with low follicular estradiol production, resulting in suppression to subsequent luteal profile leading to substantial decrease in pregnancy consequence of buffaloes.