One of the places I hunt is a cattle farm. The deer do not mind the cows, but I don' t think they love them either. We have killed a few out of pastures that had cows in them at the same time(although no big bucks). About the only thing I know for sure, is that the deer will change their patterns immediately when the cows get rotated. They will eventually get used to them being there...and gradually settle back into their patterns, thought not completely. Unfortunately, the farmer tends to rotate the cows to the exact areas we plan on hunting about 2 days before we show up. LOL....always seems that way...