COMPARISON BETWEEN THE CPM OF EARLY HEIFERS AND THE PREGNANCY RATE IN THE IATF DURING THE 2020/2021 MOUNTING SEASON

Abstract

The objective of this study was to evaluate and compare the pregnancy rate with the CPM of early purebred Nelore heifers by origin (PO), during the Fixed Time Artificial Insemination (FTAI) program. By comparing the scores given to each animal in the categories and the pregnancy rate. For the experiment, 356 precocious heifers with an average age of 14.6 months, belonging to a property located in a municipality in the state of Rondônia, raised in an extensive regime, divided into three lots and submitted to the same FTAI protocol (D0 2mg of estradiol benzoate + implantation of bovine intravaginal device with 1.0 g of progesterone, D7 implant removal + estradiol cypionate 0.5mg + 200 IU eCG + Cloprostenol 1.6 ml, D9 FTAI). Heifer batch I contained n=116 animals, batch II n=140 and batch III n=100. The total pregnancy rate per batch was respectively 76.72% (89:116), 75.71% (106:140) and 62% (100:62).