Changes

==Consequences of Methionine and Cysteine Deficiency==

==Consequences of Methionine and Cysteine Deficiency==

====Dogs:====

====Dogs:====

Puppies fed a methionine deficient diet experience decreased food intake, weight loss and evidence of dermatitis<ref name="Milner">Milner JA. Assessment of indispensable and dispensable amino acids for the immature dog. J Nutr 1979;109:1161-1167.</ref>. In puppies Methionine deficiency in combination with excess cysteine resulted in hyperkaratotic, necrotic foot pad lesions<ref name="Burns">Burns RA and Milner JA. Sulfur amino acid requirements of immature beagle dogs. J Nutr 1982;112:447-452.</ref>, that resolved with reintroduction of methionine. Inadequate intake of sulphur amino acids without supplemental taurine has also been associated with development of taurine deficient cardiomyopathy<ref name="Torres">Torres CL, et al. Taurine status in normal dogs fed a commercial diet associated with taurine deficiency and [[Dilated Cardiomyopathy|dilated cardiomyopathy]]. JAPAN(Berl) 2003;87:359-72.</ref><ref name="Backus">Backus RC, et al. Low Plasma Taurine Concentration in Newfoundland Dogs is Associated with Low Plasma Methionine and Cyst(e)ine Concentrations and Low Taurine Synthesis. J Nutr 2006;136:2525-2533.</ref>, and pigmented gallstones<ref name="Christian">Christian JS and Rege RV. Methionine, but not taurine, protects against formation of canine pigmented gallstones. J Surg Res 1996;61:275-281.</ref> in adult dogs.  

Puppies fed a methionine deficient diet experience decreased food intake, weight loss and evidence of dermatitis<ref name="Milner">Milner JA. Assessment of indispensable and dispensable amino acids for the immature dog. J Nutr 1979;109:1161-1167.</ref>. In puppies, methionine deficiency in combination with excess cysteine resulted in hyperkaratotic, necrotic foot pad lesions<ref name="Burns">Burns RA and Milner JA. Sulfur amino acid requirements of immature beagle dogs. J Nutr 1982;112:447-452.</ref>, that resolved with reintroduction of methionine. Inadequate intake of sulphur amino acids without supplemental taurine has also been associated with development of taurine deficient cardiomyopathy<ref name="Torres">Torres CL, et al. Taurine status in normal dogs fed a commercial diet associated with taurine deficiency and [[Dilated Cardiomyopathy|dilated cardiomyopathy]]. JAPAN(Berl) 2003;87:359-72.</ref><ref name="Backus">Backus RC, et al. Low Plasma Taurine Concentration in Newfoundland Dogs is Associated with Low Plasma Methionine and Cyst(e)ine Concentrations and Low Taurine Synthesis. J Nutr 2006;136:2525-2533.</ref>, and pigmented gallstones<ref name="Christian">Christian JS and Rege RV. Methionine, but not taurine, protects against formation of canine pigmented gallstones. J Surg Res 1996;61:275-281.</ref> in adult dogs.  

====Cats:====  

====Cats:====  

Feeding of a methionine deficient diet to kittens resulted in weight loss, lethargy and abnormal ocular secretions<ref>Teeter RG, et al. Essentiality of methionine in the cat. J Anim Sci 1978;46:1287-1292.</ref><ref>Rogers QR and Morris JG. Essentiality of amino acids for the growing kitten. J Nutr 1979;109:718-723. </ref>. Deficient methionine intake with adequate cysteine supplementation intake in kittens also resulted in severe perioral and foot pad lesions<ref name="NRC"/>.  

Feeding of a methionine deficient diet to kittens resulted in weight loss, lethargy and abnormal ocular secretions<ref>Teeter RG, et al. Essentiality of methionine in the cat. J Anim Sci 1978;46:1287-1292.</ref><ref>Rogers QR and Morris JG. Essentiality of amino acids for the growing kitten. J Nutr 1979;109:718-723. </ref>. Deficient methionine intake with adequate cysteine supplementation intake in kittens also resulted in severe perioral and foot pad lesions<ref name="NRC"/>.

==Toxicity==

==Toxicity==