Sparkle is feeling a bit like an Ill Wish Doll these days with all the needle sticks for the blood needed to track her progesterone level.
We check progesterone because it is a clue about Luteinizing Hormone (LH), which is the trigger for ovulation in mammals. LH is transient and easy to miss, even testing once each day.
When progesterone hits a certain value, the LH surge has occurred — we call that Day 0; ovulation begins on Day 2.
The eggs need to mature and so fertilization cannot occur in dogs before maybe Day 3, and Days 4 - 6 are actually the optimal breeding days.
Poor timing is a typical reason for breeding failure. Sparkle is almost six — we cannot afford to fail.
A slight complication is that experts have different ideas of the progesterone value that reflects the LH surge and therefore, ovulation.
Anything over 0.9.
1.8 - 2.5.
2.0 - 3.0
To help you understand how the variability in values might complicate things, consider Sparkle’s progesterone numbers:
Tuesday @ 1 pm: 0.36
Wednesday @ 2 pm: 0.6
Thursday @ 2 pm: 0.9
Friday @ 12 pm: 2.6
Yesterday’s value of 2.6 likely represents the LH surge. But it is possible that she had the surge late on Thursday, depending on whose progesterone values one uses to reflect the LH surge. Therefore, one could support Thursday or Friday as Day 0 for Sparkle.
We have set aside serum from each day’s progesterone test and will check for the presence of LH in the samples with progesterone values suggesting the LH rise — Friday’s sample for sure.
It is complicated, isn’t it? Personally, I think the intentional and thoughtful creation of life should be complicated.
We check progesterone again this morning. This involves driving to Missoula and having the blood drawn, and then I deliver it to the human hospital lab; results are typically available in 2 - 3 hours.
If Thursday was Day 0, breeding should begin on Monday. If Friday was Day 0, breeding should begin on Tuesday. We will see what the LH says but I am inclined to start on Monday — just to be sure.
And so we leave tomorrow — it is a bit of an unusual Destination Wedding.
Are your Lucky Socks ready for all this?