Fertility Response using Timed Insemination Protocols in Sub-oestrus Buffaloes

Fertility response to fixed time artificial insemination protocol was studied in 45 sub-oestrus buffaloes divided randomly into three groups (n=15). Animals of group-I were administered intravaginal progesterone implant for 7 days along with GnRH (day 0) followed by PGF₂α (day 7). Animals of group-II were administered GnRH (day 0), followed by PGF2α (day 7) and a second GnRH (day 9). Animals of group-III were treated similar to group-II followed by long acting biphasic Insulin on day 9, 10 and 11. Timed artificial insemination was performed on 10^th and 11^th day at an interval of 24 hours in all the groups. Based on the intensity of the oestrus signs observed during fixed time artificial insemination the oestrus synchronization was graded as excellent, good, fair, poor and nil. The results revealed better grades of oestrus synchronization in insulin modified Ov-synch protocol (GIII) as compared to the original Ov-synch (GII) and progesterone implant (GI) group. The higher conception rate was recorded in insulin modified Ov-synch (73.33%), followed by progesterone implant (60.00%) and Ov-synch protocol (46.66%).