This is probably a greenhorn question, but I am aware that it is sometimes difficult to get a heifer to breed back after her first calf. If a heifer fails to breed back and doesn't have another calf within a year, and then several more months can be added to that, are there any negative issues that can arise with a long span between calves? Any difference in ease of calving, milk production, caring for the calf, or do things usually proceed as usual?