Again Jill has shown that she has the wisdom of Solomon. There are so many cows out there that are so marginal in their calving ability. If these cows have any calving issues, the sire used is almost always given the total blame for this happening. In some cases the sire should be blamed, but I suspect some of these cows would have problems calving most any bull of any breed. How genetics manifest themselves is always a bit of a mystery as well. Sometimes, a cow can be bred to a certain bull and have very normal sized calves and then have a monster the next time from the same sire and the same management. Some things are not always black and white issues.
Let's all use some caution is seeking calving ease and lower birth weights in our calves. There is enough research that shows that selection for low BW for a few generations also results in smaller pelvic size in the females produced. If we want to see some major calving issues, just continue down the road of selecting the lowest BW sires available and keep the daughters. In a few years, you will probably be an expert on calving problems.
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