Comparative Efficacy of CIDR-Based Estrus Synchronization Protocol in Post-Partum Anestrus Gir and Ongole Cows under Field Conditions

This study investigates the effectiveness of a Controlled Internal Drug Release (CIDR) protocol in synchronizing estrus among post-partum anestrus Gir and Ongole cows, under field condition in Nalgonda district, Telangana. The study aimedto improve reproductive outcomes under field conditions. Anestrus, a major cause of infertility in Indian Zebu cattle breeds, reduces reproductive efficiency by prolonging calving intervals and lowering fertility rates. Twelve post-partum anestrus cows, comprising six Gir and six Ongole cattle breeds, were selected for this study. The cows underwent a CIDR-based fixed-time artificial insemination (FTAI) protocol, which included administering GnRH and PGF2α hormones. The protocol’s impact was assessed based on estrus response rate, onset of estrus, duration of estrus, conception rate, and plasma progesterone levels. Results showed that the CIDR protocol achieved a 100% estrus induction rate in both breeds, with conception rates of 100% in Ongole and 94% in Gir cows. Progesterone analysis indicated a significant (P<0.05) rise in levels on day 7, followed by a significant decrease (P<0.05) around insemination. The study highlights the CIDR protocol's potential for enhancing reproductive performance by synchronizing estrus, leading to higher conception rates in native cattle breeds under field conditions.