Different Types of Luteal Sub-Function in Relation to Pregnancy RateIn Nelore Cattl

Abstract

This study was carried out to determine different types of luteal sub-function in relation to pregnancy rate in Nelore cattle. Fifty seven cows were used. Blood samples were collected twice per week for determining progesterone concentration within estrous cycle. Seven progesterone profiles were found normal progesterone profiles, delayed progesterone profiles, insufficient progesterone profiles, short luteal phase, long luteal phase, basal progesterone profile, and non-response to prostaglandin F2 treatment. Normal progesterone profiles (52.8 %) were higher than abnormal progesterone profiles. Therefore, pregnancy rate was significant higher in normal progesterone profile (45.6 %) compare to other abnormal progesterone profiles. In conclusion, Different progesterone profiles were observed in individual animal after AI. In addition to, it was observed that the post insemination progesterone profile has an effect on the pregnancy rates in Nelore cattle. Keywords: progesterone profiles, pregnancy rate, artificial insemination, Nelore cattle