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 …

This manuscript focuses on potential changes in reproductive physiology that occur due to
high milk production in lactating dairy cows. Four reproductive measures are discussed …

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 …

The objective of this study was to determine risk-factors affecting increase in physical activity
during estrus and pregnancy per artificial insemination (P/AI) in lactating dairy cows. Cows …

Contents Fertility in high yielding dairy cows is declining, and there is increasing evidence to
presume that oocyte and embryo quality are major factors in the complex pathogenesis of …

The objective was to evaluate if expression of estrus by dairy cattle altered fertility in timed
artificial insemination (AI; n= 5,430) or timed embryo transfer (ET; n= 2,003) programs that …

Contents Dairy cow fertility has been declining during since the mid‐80s and this has given
rise to numerous scientific studies in which important parts of the pathogenesis are …

Several studies using transrectal ovarian ultrasonic scanning in Bos taurus (B. taurus) cattle
and more recently in Bos indicus (B. Indicus) females evaluated the reproductive cycles of …

During the last decade, researchers have studied the differences in the reproductive
physiology between Bos taurus and Bos indicus breeds. This manuscript focuses on the …

The objective of this study was to evaluate the factors that may affect conception rates (CR)
following artificial insemination (AI) or embryo transfer (ET) in lactating Holstein cows …