IMPACT OF ESTRADIOL BASED MODIFIED SYNCHRONIZATION PROTOCOL ON EXHIBITION OF BEHAVIOURAL ESTRUS IN BUFFALO (BUBALUS BUBALIS)

The present study was aimed to compare the behavioral estrus signs and uterine tone exhibited by buffaloes subjected to traditional heat synch and a modified heat synch (G6G-Heatsynch) protocol in which a gonadotropin releasing hormone (GnRH) injection was administered two days after prostaglandin (PGF2α) and six days prior to the Heat synch protocol. A total of 50 postpartum clinically healthy and cyclic buffaloes were randomly divided into two groups. Buffaloes of Group 1 (n=25) were treated with G6G-Heatsynch protocol whereas Group 2 (n=25) buffaloes received the traditional Heat synch protocol. Various behavioral estrus signs viz. frequent urination, vulvar swelling, cervical-vaginal mucus (CVM) discharge, bellowing and uterine tonicity were recorded on the day of fixed time artificial insemination (FTAI) and a comparison was carried out between both groups based on display of these estrus signs. Frequent urination, vulvar swelling and bellowing were present in all the animals of both groups whereas CVM was observed in 80 and 68% buffaloes of Group 1 and 2, respectively. High uterine tone was exhibited by 44% buffaloes of Group 1 compared to 32% buffaloes of Group 2. Furthermore, frequent urination, vulvar swelling and bellowing were observed in all the animals of both groups irrespective of their subsequent pregnancy status. On the other hand, higher proportion of pregnant buffaloes showed CVM discharge compared to non-pregnant ones in Group 1 (P<0.01) and 2 (P<0.05). Pregnant buffaloes also had higher uterine tonicity at the time of FTAI than non-pregnant buffaloes of Group 1 (P<0.05) and 2 (P<0.01). In conclusion, estradiol-based synchronization methods were successful in eliminating estrus detection problem. Further, CVM discharge and high uterine tonicity at the time of AI were prominent signs to predict successful pregnancy in buffaloes subjected to estradiol-based synchronization protocols.