“Nutritional Adequacy of Two Vegan Diets for Cats”, Christina M. Gray, Rance K. Sellon, Lisa M. Freeman2004-12 (taurine (cat))⁠:

…To our knowledge, no analysis of vegan foods formulated for cats and commercially available in the United States has been reported. Therefore, our intent was to analyze 2 commercially available vegan diets to assess whether they met the minimum nutrient amounts cited in the Association of American Feed Control Officials (AAFCO) Cat Food Nutrient Profiles.

…Results of analysis of the 2 vegan diets were compared with the AAFCO Cat Food Nutrient Profile for adult maintenance (Table 1). Both diets had multiple nutrient deficiencies. Diet B was low in protein (62 g/1,000 kcal), and some amino acids were in amounts less than those cited for the AAFCO adult minimum amounts. Both diets contained less than the AAFCO minimum amounts for methionine and taurine. Diet A also was low in arginine and lysine content. Of particular concern was the low taurine content in both diets. Assuming that diet A should be considered similar to an extruded diet, the AAFCO minimum taurine concentration would be 0.25 g/1,000 kcal; however, diet A contained only 0.06 g of taurine/1,000 kcal (< 25% of the AAFCO minimum). The AAFCO minimum amount of taurine for canned food is 0.50 g/1,000 kcal, but diet B (a canned food) contained < 0.09 g of taurine/1,000 kcal (< 20% of the AAFCO minimum).

…The 2 vegan diets tested were also low in content for a number of amino acids. Because taurine is abundant in animal sources but not in plants, vegetarian diets require supplementation with taurine. This is not to say that the need for supplementation is unique to vegan diets because many meat-based diets are also supplemented to achieve AAFCO minimum amounts. Both of the diets analyzed here were supplemented with taurine, yet the analysis revealed that both diets contained less than the AAFCO minimum. The low taurine content found in both of these diets may have far-reaching implications because of taurine’s importance in the function of multiple organ systems. Syndromes that result from taurine deficiency include central retinal degeneration, dilated cardiomyopathy, poor growth, and reproductive failure as well as nervous and immune system dysfunction.^{2–5,8,10,13}