I have neighbor who in the last 10 years has had 3 years where calves have died. This year 2 calves that were several months old died. The vet thinks it was pneumonia. The other 7 years no animals have died. The only connection between this year and the other 3 were that the pastures these calves were in, were cut in June. The other 7 years he always waits until end of July or early August. Is there a possible connection between the early cutting (brush hogging) of the pasture and these calves early deaths?