Monday, July 21, 2014

Zene is in season --- progesterone testing explained!

Woohoo!  Zene has come into season!  Progesterone testing will start around Day 9 or 10 of her heat cycle.  I will coordinate with the owners of Spenser to send a "(sperm) collection" for an artificial insemination breeding to be done at my vet; Yorba Regional Animal Hospital. 

What the heck is progesterone testing, you ask?

Basically, progesterone is a hormone produced by the ovaries that rises as the heat cycle progresses.  Early in the canine heat cycle the progesterone values will usually read less than 1.0 ng/ml.  The first significant, sustained rise in progesterone usually coincides with the "LH Surge".  The LH stands for luteinizing hormone and is released by the pituitary gland in the brain.  This is important because ovulation occurs about 48 hours after the LH surge.  The progesterone value at the time of the LH surge is usually about 2-3 ng/ml. The progesterone will rise to about 5-8 ng/ml at the time of ovulation.  Canine eggs are not ready to be fertilized at the time of ovulation and take about 2 days to mature.  Once mature, the eggs remain fertile for 2 to 3 days and then begin to deteriorate.  Of note: progesterone stays elevated for about 2 months whether the bitch is pregnant or not.  We like to know when the "surge" is so that we have an idea of ovulation, when to breed, and to estimate the whelping day.

And now you know ;)