PSV-B-24 - Palatability assessment of graded levels of grain distillers dried yeast (GDDY) fed to healthy adult cats

Traditionally, yeast products have been added to companion animal diets to improve palatability. Grain distillers dried yeast (GDDY), a coproduct from ethanol production which contains yeast, may be a viable option in pet food. The objective of this study was to determine the effects of increasing levels of GDDY in cat diets compared to soybean meal. The control diet contained 15% soybean meal (CON) and GDDY was exchanged for soybean meal at either 5%, 10%, or 15% (5G, 10G, 15G). For each test, experimental treatments were compared to the control. Twenty cats were presented two bowls each containing approximately 100g of diet once daily for 2 days. Cats were given diet access for 4 hours and bowl placement was reversed on the second day. Total food consumption and first choice preference were recorded for each cat. Individual intake ratios (IR) were calculated (intake of each diet/total intake) and first choice (FC) was analyzed with a Chi² test. When comparing 5G to CON, the IR was 0.970 with FC of 30/40 occasions (P = 0.0016). The IR for 10G was 0.538 and FC was 18/40 with no difference from the CON (P = 0.5271). The IR for 15G was 0.590 and FC was 19/40 with no difference from the CON (P = 0.7518). Overall, these results suggest that cats may prefer GDDY over soybean meal, but preference may be influenced by inclusion level with the greatest impact observed at 5% and no detrimental impact at 10 or 15%.