|
|||||||
Commercial Services Program Topics Testing Options Online Information Test Results |
 |
Progesterone profiling, one of the most important tools in reproductive physiology, can be incorporated into any synchronization program to find out if your cows were really ready for insemination. Because of its role in early embryonic growth, uterine environment and luteal function, progesterone concentration is a critical determinant of conception and pregnancy. The progesterone profiles in the figure below demonstrate several time points where progesterone concentrations can help predict the readiness of your cows at insemination.
An example of how Sync
|
|||||
|
|||||||
– Progesterone Profiling for Reproductive Accuracy
Presynch. Most cows should be synchronized by the second prostaglandin administration as demonstrated by high progesterone concentrations. Although the luteal phase of the initial cycles following calving might not be associated with sufficient progesterone to produce and sustain a pregnancy, higher progesterone levels at this point indicate readiness to enter a successful synchronization program.
GnRH. There is a positive association between progesterone concentrations during the early luteal phase of the estrous cycle and pregnancy. Serum and milk progesterone concentrations should be high (>2 ng/mL and 4 ng/mL, respectively) in the vast majority of cows at this time point reflecting a recent ovulation in response to previous administration of prostaglandin or GnRH.
Prostaglandin and AI. Progesterone levels in serum and milk should decline rapidly after prostaglandin administration from peak concentrations of 7 ng/mL and 18 ng/mL to less than 0.5 ng/mL and 2 ng/mL, respectively. Patterns of early luteal regression (low progesterone at the time of prostaglandin administration) or incomplete luteal regression (high progesterone at the time of AI) are inconsistent with the timing of embryonic signals to successfully establish pregnancy.