Abstract
The aim of this study was to evaluate the effect of the hormonal treatment during early postpartum period on the days open, serum progesterone hormone levels at 28 and 42 days post injection and pregnancy percentage following different hormone protocols in multiparous and primiparous buffaloe- cows. The experiment was carried out on 65 (40 multiparous -25 primiparous) clinically healthy animals, randomly allotted into five groups: each (n=8) multiparous and (n=5) of primiparous. The first group; received saline 0.9% intramuscular at day 14 postpartum (control). The second group; injected by 5 ml Receptal (20 µg Buserelin ) at day 14 post-partum. The third group; injected by 5 ml Receptal at day 14 post-partum and day 21 then 3ml Estrumate (750 µg cloprostenol) at day 28. The fourth group received 2 vials of Gonaser (1000 IU eCG) at day 14 post-partum. The fifth group injected by 1000 IU eCG at day 14 post-partum, and at day 21 receive 5 ml Receptal then 7 days later at day 28 receive 3ml Estrumate. Fertile bulls were ensured for all buffaloes. Blood samples collection were performed at the days 28 and 42 day from treatment for serum progesterone levels determination. Ultrasound pregnancy check was done at day 40-45 days later. The present study demonstrated that group 4 has significant (P>0.05) decrease of the current days open than other groups of multiparous buffalo and have lower significant (P < 0.01) difference from previous days open and Primiparous buffaloes. Meanwhile, control group showed the highest current days open (113.3 ± 4.4) compared to other groups of multiparous buffalo cows and have significant (P < 0.05) difference from primiparous buffalo cows. Highly significant (P < 0.05) differences in serum progesterone concentration at 28 and 42 day among groups of multiparous buffalo cows where, group 4 at 28 day had greater (0.56±0.11 ng/mL) concentration than both group 2 (0.31±0.07 ng/mL) and group 3 (0.29±0.06 ng/mL). No significant differences in percentages of pregnancy rates within multiparous and primiparous buffaloes but group 1 and group 3 of primiparous buffaloes had the lowest pregnancy rate percentage compared to other groups. In conclusion, the application of hormonal treatment during early postpartum period at day 14 postpartum especially group 4 resulted in decreased days open and could be used for improvement of the reproduction in postpartum buffaloe-cows.

Key words: postpartum - days open - pregnancy rate - buffalo