Cats Require More Dietary Phenylalanine or Tyrosine for Melanin Deposition in Hair than for Maximal Growth

摘要: In 1986, the NRC recommended a dietary concentration of 4.0 g/kg phenylalanine and 8.5 total aromatic amino acids for growing kittens on basis maximal growth rate nitrogen balance. Black hair-coated cats were given purified diets containing following + tyrosine (Phe Tyr) concentrations (g/kg diet): 4 2, 4, 6, 8, 10 0, 10, 24 0 at least 6 mo. All other present about twice requirements. Total melanin oxidation product eumelanin, pyrrole-2,3,5-tricarboxylic acid (PTCA) measured in hair. There was significant linear relationship between plasma PTCA The hair Phe Tyr diet had point inflection approximately 16 Tyr. Cats fed with or =18 is prevention visually discernible red black-coated cats. Dietary >18 g acids/kg promote greater ratio PTCA:total We are unaware secondary nutrient requirement being so much than growth.