Progesterone

• Send serum only.
• Centrifuge blood and remove serum from clot.
• Ship with cold packs OVERNIGHT Monday-Thursday.

1. Timing of breeding

The ovulatory LH surge usually happens on the day when the serum progesterone concentration for the first time exceeds 2 ng/mL; ovulation usually happens when the serum progesterone concentration exceeds 5 ng/mL; Oocytes mature to the secondary oocyte stage (when they can be fertilized) two days AFTER ovulation (or 4 days after the LH surge) and remain viable for 3-4 days. Optimal time for breeding is therefore 4-6 days after the LH surge or 2-4 days after ovulation

2. Timing of elective cesarean section

A sudden, precipitous fall in serum progesterone concentration, rather than an absolute value indicates that he bitch will whelp within 24 hours of collecting the most recent serum sample; therefore, a series of daily serum progesterone concentrations in samples collected from 62 days after the LH surge (or 58 days after the last breeding) will be of most value when attempting to identify the last day of gestation

3. Hypoluteoidism

• As long as serum progesterone concentrations stay above 2 ng/mL abortion due to hypoluteoidism is unlikely
• Exogenous progestogen therapy is usually indicated when serum progesterone concentrations fall below 5 ng/mL at day 50 after the LH surge

For further advice contact the Theriogenology Service of the VHC at (573) 882 1594