title: Dietary protein levels affect water intake and urinary excretion of magnesium and phosphorus in laboratory cats.
abstract: The effects of dietary protein levels on food and water intake, and urinary excretion of magnesium (Mg) and phosphorus (P) were examined in cats fed dry-type diets. Four adult female cats were used for trials in a 4 x 4 Latin square design, and fed diets with increasing protein content (25.9, 38.3, 51.4 or 65.2% in dry matter) daily from 9:00 to 13:00. While daily food intake was almost constant regardless of the dietary protein level, water intake and urine volume increased with increasing the dietary protein. Daily urinary excretion of P increased in response to the increase in dietary protein level. The urinary concentration of P was positively related to nitrogen (N)-intake. In contrast, daily urinary excretion of Mg was not affected by the dietary protein level, and the urinary concentration of Mg was negatively related to N intake. A dry-type diet with a high protein content might be effective in preventing the deposition of Mg salts in the urinary tract of cats under the meal-fed condition without affecting food intake because of both the lower concentration of urinary Mg resulting from the increase in urine volume and, probably, urinary acidification.
authors.affiliation: Research Center, Nihon Nosan Kogyo K.K., Ibaraki, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Hashimoto
authors.forename: M
authors.initials: M
authors.lastname: Funaba
authors.forename: M
authors.initials: M
authors.lastname: Abe
authors.forename: S
authors.initials: S
authors.lastname: Ohshima
mesh_terms: D000818:Animals; D002415:Cats / Q000378:metabolism*; D004044:Dietary Proteins / Q000008:administration & dosage*; D004231:Diuresis; D004326:Drinking; D004435:Eating; D005260:Female; D008274:Magnesium / Q000652:urine*; D010758:Phosphorus / Q000652:urine*
chemical_list: D004044:Dietary Proteins; D010758:Phosphorus; D008274:Magnesium