One of the reproductive services offered at Animal Health Services is progesterone testing for the bitch.
What is Progesterone and why would I test for it? Progesterone is a hormone that helps prepare and maintain the uterus for pregnancy. It begins to rise during the estrus cycle and is a key indicator (along with the Luteinizing Hormone, or LH) of when ovulation occurs.
Why would I test my bitch’s progesterone levels? To determine when ovulation occurs and hence when is the best time to breed.
How do you test for it? It is a simple blood test. While all veterinary laboratories offer the test, Antech Laboratories uses the RIA (Radioimmune Assay Test), which is considered the most accurate and is the gold standard. In-house tests are available also, but do not provide the level of accuracy obtained from Antech.
When do I start testing my bitch’s levels? Typically 5 – 6 days after estrus discharge is noted. Occasionally we will start testing earlier or later based on previous reproductive history.
Can I find out when my bitch will be going into heat based on a progesterone test? No – the progesterone level doesn’t begin to rise until she starts into heat. During anestrus (between heat cycles) there is no measurable progesterone.
What is the frequency of the testing? Roughly every other day. We may go two days at the beginning if the first level is very low, and we may repeat daily, particularly when doing a surgical insemination with frozen semen, which requires more precise numbers.
Can my pet be tested on Sunday? YES! We will get those results for you on Monday.
How soon do I get results? Usually by 9 am the next day. We do have a human endocrinology laboratory that can get us same-day results, but it is generally not necessary to do so, and the price is substantially higher.
What is the target level for breeding/insemination? It will vary depending on the type of breeding planned. For a natural breeding with a local stud, once the level rises above 2.5 we recommend putting the dogs together. For chilled semen inseminations we generally arrange the shipment once the progesterone has gone above 3.0, but we still want to confirm that the progesterone has risen above 5.0. For surgical inseminations with frozen semen, we plan the insemination after the progesterone has risen above 5.0.
Do different breeding methods or types of semen (chilled/frozen/fresh) require different progesterone levels? Yes (see above). The less the sperm have been handled the longer they live, so with a fresh insemination or natural breeding there is a larger margin of time than with frozen semen.
How soon can I tell if my bitch is pregnant based on her progesterone level? Or can I? The progesterone level will rise with ovulation and then remain high throughout the gestation period whether or not the bitch is pregnant (even if she is not bred).
What is the target level my bitch needs to maintain to support pregnancy? Above 5.0. Typically the progesterone level will rise to 10.0 or higher after ovulation.
What effect does the progesterone level have on a caesarean section? The progesterone level can be used to time a c-section. A drop in the progesterone level will signify the commencement of labor within 24 hours. If the due date cannot be accurately determined, daily progesterone tests can be done to determine when that drop occurs in order to schedule the c-section at the optimum time.
Progesterone levels vary not only from bitch-to-bitch but from cycle-to-cycle in an individual bitch. One who ovulates late in her first cycle will not necessarily do the same in successive cycles.