It isn't as simple as just giving them meat and that's it - but it isn't too hard either -- they need 80% muscle meat (inc heart), 10% other meat (kindey liver etc) and 10% bone. The way I find the best to make sure they are gettting everything that they need is to buy it ready made up from
www.food4-cats.co.uk. It comes in ready made sausages of 400g - which are roughly 40-80p depending on the meat. You feed 2-3%of your cats body weight -- so a 400g sausage should last 2-4 days per cat depending how heavy they are.