Evaluation of Raw Yeast Extract (Saccharomyces cerevisiae) as an Ingredient, Additive or Palatability Agent in Wet Diet for Cats

Three experiments were performed to evaluate the effects of strain-specific yeast extract (SSYE) as an ingredient, functional additive or palatability agent when supplemented in its raw form in wet cat food. SSYE as ingredient – SSYE was chemically characterized and its use evaluated through fourteen cats divided into two treatments: control diet (complete wet adult cat food) and control diet with 30 % replacement by SSYE. The results of apparent digestibility coefficient of SSYE were 71.64 % for dry matter, 72.55 % for organic matter, 50.78 % for ashes, 78.59 % for crude protein, 84.33 % for the energy gross and digestible and metabolizable energy value, respectively, of 4,247 and 4,163 kcal/kg, these results indicated that SSYE is comparable to other protein sources for cat’s food. SSYE as a functional additive - twelve cats were distributed into two 6x6 latin squares (treatments; experimental periods), and the treatments were control diet and replacement levels ranged from 2 % to 10 % SSYE. The following parameters were evaluated: digestibility, energy utilization, nitrogen balance, serum urea and creatinine levels. No differences were found. SSYE as palatability agent – Were used twenty cats by comparing the control diet with 2 % replacement by SSYE. A significant difference (P < 0.01) was observed with a preference for control diet. SSYE is a potential protein source for cats; however, it is not effective as additive and may compromise palatability when supplemented in its raw form in complete wet cat food.