Hello; Not too worried about mutant cows. I do have a pasture along one side of my property. Will hold up to 20 or so cattle at one time. They are curious but generally calm. I can mow next to the fence, and they just calmly watch.
A thing is they are big and heavy. This past year one got out and was in my back yard. It had been raining. The hoof prints were several inches deep in the soft ground. Farmers get hurt around them. Get pinned against objects, stepped on and such. Cows do not have to be anything other than big & heavy to run over you if they panic.