I'd put them on a diet..............
Then you'd be underfeeding them. The BSH is a heavy boned Cat that weighs more than my Terriers, the brown one weighs almost 22lb! Their coats are over an inch thick and stand off the body, they are not smooth haired cats. None of them are overweight, not even an ounce, I wouldnt dream of keeping unfit animals. You are forgiven for thinking they maybe though, and I appreciate your apparent concern.
Ok then.........i wont argue cause i dont know the type of cat. But they do look fat. Do these cats get out?