The reason I ask is, I had a cow that checked safe in June, last week she was in heat so I bled her again and now she is open. The two in question are not showing signs of heat but now I am getting paranoid. I have a small herd and can't afford to feed open cows.
We AI'd 17 hd. of heifers in May, then put bull in, the vet ultrasounded at 90 days and one was open and two were in the process of absorbing the fetus. Had the vet checked by hand he would have called them bred, but with the ultrasound he could tell that they were absorbing the fetus and sure enough they are cycling again. I asked why they would be doing this and he said that everything looked and felt good inside, so he concluded that it was the hot and dry weather. So there might be a higher % of open cows - heifers this fall (spring calvers) because of the heat.
Also on a different note, a relative of mine who is a vet had AI'd some heifers to calve this fall, he lost like 7 or 8 calves, they were either born dead or really weak and died immediately, took samples and sent to the University of MO and they said hot weather was the cause, the heifers just had trouble keeping themselves cool. I think they said it was just a lack of oxygen in the blood for the calf at a given point?