Royal canin believes that a cats diet should reflect the various parameters of life such as age breed lifestyle physiology and individual circumstances this also includes the food you feed your cat after it has been neutered royal canin sterilised in gravy helps your pet to maintain a healthy weight after sterilisation within 48 hours of neutering your cats food intake has increased by 20 however the energy it needs has reduced by about 30 lowering the calorie intake leads to a sli