This study provides important information concerning
the effectiveness of the use of eCG in FTAI programs for
beef Bos indicus heifers, confirming the hypothesis. The
present results demonstrated that Nelore heifers treated
with eCG achieved greater ovarian responses and P/AI than
heifers without eCG treatment. In addition, the administration
ofeCGon Day 8 of the estrous synchronization protocol
necessitated no changes in animal handling, management
or labor. However, it is important to emphasize that the
efficacy of progestin-based protocols can be influenced
by the ovarian status at the beginning of the treatment.
In the present study, heifers without CL on the day of
progestin-implant insert had a lesser growth rate of the
LF from the time of implant removal until FTAI (Days
8–10), smaller CL diameter 5 days after FTAI and reduced
P/AI.