I have cows where I hunt and usually the deer just eye the cows and give them some room if they are both in the field. They will actually pay less attention to you as long as you don't draw attention to yourself. Try to avoid the cattle hotspots because the deer will try to stick to cover and avoid them. The best spot to hunt is along a field they cross between where they feed and bed. You will see deer in the early morning and late evening and depending on hunting pressure and the weather possibly in between. Don't be afraid to step in some cow s*** as you go to your stand, it will smell like a natural part of their surroundings.

And whatever you do don't shot a just a brown spot. You could wind up buying a whole cow off a farmer.