Body water content and turnover in cats fed dry and canned rations

Body water content and total body water turnover in cats fed commercially available dry food and then given canned rations were determined with tritiated water. Cats during the feeding of either ration did not differ in body water content or turnover. Cats during the feeding of the dry ration derived a greater fraction of their total water turnover from drinking water, and these cats drank more water per gram of dry matter intake than when fed the canned ration. On the basis of total water intake, however, those given the canned ration had significantly greater water intake per gram of dry matter; also, their total water turnover per gram of dry matter was greater. Compared with other animals, cats have a similar ratio of body water to body solids, but the rate of water turnover per unit of body weight is slower.