Relationship between Body Condition of Cows with Incidence of Estrus and Pregnancy Rate

Abstract

The aim of this study was directed towards correlating the body condition score with estrus and pregnancy rate in Nellore cattle. Eightythree cows were randomly selected for the study. Cows were observed for estrus and artificially inseminated. Blood samples were collected twice weekly after estrusduring a whole estrous cycle of 21 days. Cows were scored for body condition based on a 1 to 9 scale. According to body condition score (BCS), cows were subdivided into five groups: BCS 2 (5 cows), BCS 3 (11 cows), BCS 4 (34cows), BCS 5 (26 cows) and BCS 6 (7 cows). Cows with BCS 5 exhibited higher estrus(88.4 %) and pregnancy rate (46.1 %) compared to other cows with BCS of 2, 3, 4 and 6. Progesterone profile was normal in cows with BCS 3, 4, 5 and 6. However, progesterone profile in cows with BCS 2 was delayed and abnormal. In conclusion, higherincidence of estrus and pregnancy rate were observed in the moderate body condition cows (BCS 5). Therefore, management of cows herds should be designed to obtain and maintain cows at a BCS of 5 or greater from pre-calving through rebreeding by adjusting a good feeding program.