Book of Proceedings I PetFeeding

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ages do not always match; 2) there is quite some controversy on where and if nutritional
guidelines should differ between older and younger adult healthy cats (see review Laflamme &.
Gunn-Moore, 2014).
Probably due to their strict carnivore evolutionary nature cats developed an idiosyncratic
metabolism and, with it, a peculiar dietary requirements when compared to many other species.
This include specific amino acids (carnitine, arginine, taurine) and some vitamins (niacin, A,
and D) (read for details Morris, 2002).
Protein
Protein provides energy and is a source of nitrogen and essential amino acids. Signs of protein
and amino acid deficiencies include lack of growth (in animals that are still growing), decrease
in food intake, muscle wasting, hypoalbuminemia, skin and fur alterations, a decrease in
essential plasma amino acid concentrations, among other signs.
There are no known excess amount of protein that would cause an adverse effect when fed to
adult healthy cats. Thus, there is no upper limit recommendation in the guidelines of NRC
(2006) or FEDIAF (2017) for protein.
Minimum protein and amino acid requirements in adult cats were established using mainly
nitrogen balance studies and these were used by NRC (2006) and FEDIAF (2017) to establish
protein and amino acids recommendations. Laflamme & Hanna (2013) fed adult cats 3 different
dietary protein concentrations for 2 months. Their results showed that minimum protein intake
to maintain a zero nitrogen balance was 2.1 g/kg 0.75, whereas the amount of protein to
maintain lean body mass (LBM) was estimated to be 7.8 g/kg0.75. These researchers suggested
that to maintain adequate muscle mass higher amount of protein than the recommended by NRC
would be needed.
Arginine is needed in sufficient amounts for the urea cycle. Cats are unable to synthesize
significant quantities of ornithine or citrulline within the intestine and both are precursors to
arginine synthesis (Armstrong et al., 2010). Although only reported with experimental diets,
arginine deficiency can have dramatic effects in cats. High protein diets without arginine were
reported to cause hyperammonemia in less than one hour, with severe signs of toxicity (i.e.,
vocalization, emesis, ptyalism, hyper activity, hyperesthesia, ataxia, tetanic spasms, extended
limbs with exposed claws, apnea and cyanosis) and to cause death within two to five hours of
intake (MacDonald et al., 1984).
Taurine is a β-amino sulfonic acid, abundant as a free amino acid in the natural food of cats,
such as small rodents, birds and fish. .Many species can use either glycine or taurine to
conjugate bile acids into bile salts before they are secreted into bile. Cats can only conjugate
bile acids with taurine. Three syndromes of taurine deficiency in cats have been well
established: 1) feline central retinal degeneration, 2) reproductive failure and impaired fetal
development and 3) feline dilated cardiomyopathy (Armstrong et al., 2010). Hearing loss,
platelet hyperaggregation and impaired immune function have also been demonstrated.