Banca de QUALIFICAÇÃO: VIRGINIA APARECIDA SOUSA DE JESUS

FOLLICULAR DYNAMICS IN HEIFERS OF THE BREED Bos taurus indicus WITH HIGH AND LOW COUNTS OF ANTRAL FOLLICLES, UNDERGOING THE FIXED-TIME ARTIFICIAL INSEMINATION PROTOCOL

Follicle, Insemination, Pregnant

In the reproductive process, knowing the follicular dynamics of cows is essential to guarantee promising results in inseminations. Follicular dynamics consists of observing the evolution of follicles using ultrasound, so ultrasound combined with other biotechnologies makes it possible to increase reproductive efficiency. Fixed-time artificial insemination (FTAI) plays a crucial role in the genetic improvement of herds at a global level. The indicators of reproductive efficiency in bovine females are constantly being challenged due to the difficulties in detecting oestrus in females. It is understood that in the reproductive process, knowing the follicular dynamics of cows is fundamental to guaranteeing efficient insemination results. IATF is a biotechnique that consists of synchronizing the estrous cycle of bovine females by means of hormone therapy at a random period in the cow's estrous cycle, while follicular dynamics performed through transrectal ultrasound examination makes it possible to identify and analyse the evolution of ovulatory follicles. Thus, in order to achieve good reproductive efficiency, this study combines the IATF biotechnique with follicular dynamics. The aim of this study is to evaluate the follicular dynamics of Nelore heifers undergoing Fixed-Term Artificial Insemination, observing, analyzing and identifying the stages of ovulatory follicles in heifers on the pre-established days of D-7, D0, D4, D8 and D10.