Vol. 9, Issue 1, Part R (2024)

Author(s): Jayaganthan Ponnusamy, Satheshkumar Soundarapandian, Krishnakumar Karuppasamy, Murugavel Sokkalingam and Jagadeesan Krishnan

Abstract: Seventy-four Postpartum crossbred cows aged between 2^nd and 6^th parity were selected and randomly divided into 3 experimental groups viz., control group, group II and III. In control group, the cows (n=50) were not subjected for any treatment protocol. In group II (Dexamethasone) cows were received, Inj Dexamethasone - 40 mg I.M, for three days from Day 8 to Day 10 of the cycle (Day 0 – oestrus). Inj. Prostaglandin - 500 mcg, I.M, on Day 11. On the day of induced oestrus (Day 0i), all the 12 cows were randomly divided into 2 subgroups viz., sub group 1(Dex-GnRH): On the day of induced oestrus (Day 0i), inj. GnRH- 10 mcg I.M, was administered along with insemination and subgroup 2 (Dex-GnRH-Insulin) GnRH -10 mcg I.M and Insulin - 0.25 units /kg b. wt S.C., was administered along with the insemination. In group III (insulin) were administered with Biphasic Insulin -0.25units /kg BW S.C., for three days from Day 8 to Day 10 of the cycle (Day 0 – oestrus)’ inj. Prostaglandin - 500 mcg, I.M. was administered on Day 11. On the day of induced oestrus (Day 0i), all the 12 cows were randomly divided into 2 subgroups viz., Ins-GnRH: On the day of induced oestrus (Day 0i), inj. GnRH - 10 mcg i.m. was administered along with insemination; Insulin-GnRH-Insulin: inj. GnRH -10 mcg i.m. and inj. Insulin -0.25 units /kg BW s.c. was administered along with the insemination. In both the treatment subgroups, animals were re-inseminated on the second day and if the DF persisted, they inseminated on third day also. Serum Ca concentrations were lower on the day of mid cycle (Day 10) in both the treatment groups when compared to control group. Statistical analysis revealed a significant decrease (p<0.05) in DEX group when compared with control group. On the day of induced oestrum (Day 0i), the Ca and P levels were significantly (p<0.01) lower in INS group than DEX group.