
Wwhat you have to remeber is there is quite a wide window of opportunity.
A fertile dogs sperm can live in a bitch for a week, though stay in good condition for around 4 days. A bitch ovulates immature eggs that take two days to mature,a dn are viable for a further two days.
People are often confused with the test results. If the test is saying ovulation is occuring today then the optimum mating day is in two days, but the bitch would probably still get pregnant if she was mated 3 to 5 days ago, or was mated in four days time, though litter size may well be affected.
Also it depends on whether you are using the quantative lab tests that have a slower turn around, but actually measure the levels of hormone more acuratyely, or the Premate Kits that are not quite as accuarate but are accurate enough for most needs, giving a colour chart to compare the test with. The level of hormone causes the colour in the sample to change.
My awkward unco-operative bitch seems to be ovulating consistently on day 12. Have had her tested twice. The first time I tried mating her the dogs was dead keen on her from day 15 to 17. The next season we managed to get her mated at the end of day 16 and by day 17 the dog wasn't too fussed, according to the premate we only just caught her as she was going over, which a smaller than avergae litter born at 58 days would seem to confirm. This time he was very keen on day 15, but we only got a slip mating as she would have none of it.