We have had two calfs die this year. The first was found dead for a couple of days. Unfortunately have not been able to determine the cow, none showed interest when we removed it. The second was born to a 4 year old during the night. Found it the next morning. Both found within 50 yards of feed rings. 3 healthy calves at 2-3 weeks now. another 15 cows yet to birth. Is there anything I can do differntly?