[Animats]

Of course there are "work cats". Most large barns will have a few, for rodent control. You want them big and tough enough to take on a rat. Working cats should be fed about half what they need, so they stick around but have to hunt. Once they've cleared the barn area of rodents, they'll expand their hunting territory to find food.

(The problem is keeping cat fans from feeding the working cats. The cat people got out of control at the Stanford barn years ago, and the cats got fat and lazy. The overweight cats had to be traded out for more useful semi-feral cats.)

[PhasmaFelis]

Those aren't really "working" animals in the sense of having been bred and trained to tasks that are substantially different than wild behavior. They're just following their instincts, which happen to be beneficial to humans in this case.