The discovery of progesterone (P4) and elucidation of the mechanisms of P4 action have an
important place in the history of endocrinology and reproduction. Circulating P4 …

Timed-AI after synchronization of ovulation has become one of the most used reproductive
technologies developed during the past 40 years. Various adaptations of this technology are …

Our objective is to overview the research that lead to the development of fertility programs for
high-producing lactating dairy cows using only GnRH and Prostaglandin F 2α (PGF 2α) …

The objective of this study was to examine the association between increased physical
activity at the moment of timed artificial insemination (AI), detected by an automated activity …

This experiment evaluated the impacts of estrus expression and intensity, estimated by
physical activity during a timed-AI protocol, on reproductive performance of Bos indicus …

Lactating Holstein cows (n= 1,456) were randomized in a 2× 2 factorial design to compare
the main effects of day of initiation of resynchronization after artificial insemination (AI; 32 vs …

The presence of steroid hormones in milk is inevitable, and they can be considered as
potential carcinogenic agents for consumers. The purpose of this study was to evaluate the …

Our objective was to evaluate the effect of 3 different Ovsynch protocols on progesterone
(P4) and pregnancies per artificial insemination (P/AI), where all cows received a P4 …

This experiment aimed to compare circulating progesterone (P4), follicular dynamics, and
fertility during reuse of intravaginal P4 implants that were sanitized by autoclave or chemical …

Our objectives were to characterize parameters of luteal activity based on milk progesterone
concentration (P4c) data from before and after artificial insemination (AI) and to evaluate …