Mid Cycle Estrus in Cattle
Are you wondering about mid-cycle estrus so that you will not be breeding non-fertile animals? The cervix will not give you much indication of estrus cycle. The best way to determine is by good heat detection.
The typical estrus cycle is 21 days, starting with standing heat at day 0. At mid point of the cycle the corpus luteum is reaching maximum growth and function and is secreting progesterone. The ovaries are relatively inactive during this time.