you would have to be pretty stupid to mistake a cow for a deer

Theres a small horse pasture I drive on the way to deer camp and every year on November 14th the owner puts bright orange vests on the horses. I thought they were on all year, but they were way to orange. I asked a buddy that lives up there and says the guy only puts them on during rifle season. There is no excuse for shooting a horse or cow when your deer hunting, I really can't even see how thats possible if you follow one of the top rules in huting, know your target.

my neighbors got alot of black cows

How can you be stupid enough to shoot a cow? Most cows weigh at least 950 lbs. Calves only weigh less than 200 for about a month. Besides the fact the way a calf walks is completely different from the way a deer walks. When I amchecking cows late in the afternoon,I carry a gun during deer season. I have never even had to look twice to know whether or not it is a deer or just a calf separated from the group.