Preg checked the cows and worked the calves

I think I'm starting to understand why this blog is popular with people: everyone reads this and instantly feels much better about their own operation. So we preg checked the cows at the goat ranch last week and we got a 55% conception rate (for a 75 day breeding window). We've never had a number that bad and of course a logical person would blame the mob grazing. Maybe I'm just blind to the obvious, but I'm not ready to do that. We calve in May and June which means we breed in August and September. This past summer was record hot and Hal and I think that it had a significant effect on our bulls and to a lesser extent our cows. The cows were in pretty good shape (BCS=5) at calving and we know that is by far the most important factor in getting them rebred. I just don't understand how the mob grazing could have had much of an impact. Anyway, I'm extremely disappointed and will now be selling off nearly half of our cows in a few months (we're going to hold them for 60-90 days to try to get them bred before we sell them). I think the future is extremely bright for cow/calf producers, but I have to admit I'm looking forward to running stockers.