> i spoke to 2vets and 3 breeders and they all said not to bother as they aren't 100% accurate.
The premate kits that show if the bitch is ovulating with a colour chart are not as accurate as an elisa test where they read the levels of hormone accurately. the latter are very accurate, but of course they c an only base their advise on what the average hormone levels are for bitches at ovulation.
It is the latter test they use for timing AI, and in the USA they have a very high level of success with AI as it is used far more routinely than her.
In fact I know of no US breeder that doesn't have progesterone tests (be they premate kit of full lab Elisa).
Some bitches can ovulate as early as in the first week and some don't ovulate until after 21 days
I have never had a bitch miss more than once so have not bothered routinely testing mine, but certainly would if a bitch had missed twice.
I did use the test on a bitch that was difficult to get mated so that In would know what was going on, and the test was spot of, ans I got 4 pups, by persisting on persuading her to co-operate.
If your using the same dog his fertility needs checking.