SEXUAL PRECOCITY ASSOCIATED WITH THE CONCENTRATION OF PLASMA PROGESTERONE IN NELORE HEIFERS RAISED IN NORTHERN BRAZIL

The objective of this study was to identify sexually precocious heifers by observing ovulation (presence of corpus luteum - CL) and correlating it with the plasma progesterone concentration, as well as to verify the accuracy of the ultrasound examination (US) in this class of animals. The animals were kept in Brachiaria brizantha pastures in an extensive system with water and mineralized salt ad libitum . Nelore heifers (n=50) with initial age and weight of 10 months old and 210 kg, respectively, were used. Only 14% (7/50; p