Nutritional Adequacy and Performance of Raw Food Diets in Kittens

Feeding raw food diets to domestic cats is controversial. The objective of this study was to determine if raw feline diets were nutritionally adequate for kittens and whether they enhance immune function, reduce oxidative stress and improve digestibility. Twenty-four 9-week-old kittens underwent a 10-week growth feeding trial with two raw diet groups and one control group (commercial heat-processed canned diet) of eight kittens each. Anthropomorphic measurements, feed efficiency, oxidative stress, and blood biomarkers for innate and humoral immune function were evaluated. Additionally, 6 kittens and 4 adults participated in a 14 day digestibility trial using a 3 x 3 latin square design. Composite fecal cultures were periodically monitored for common bacterial pathogens. Both raw diets passed an American Association of Feed Control Officials (AAFCO) growth trial and had similar growth performance compared to the control diet. Minimal differences were measured in markers of innate or humoral immune function. Over time, higher lymphocyte and immunoglobulin responses were measured in kittens consuming the raw diets. A trend toward higher IgM levels was noted in one raw diet group. Higher exposure to bacterial degradation products, pathogen exposure, or nutritional differences may have stimulated a more robust immune response in the raw-fed groups. No differences in levels of oxidative stress were noted among the three groups. All kittens had decreasing levels of urinary isoprostanes over the 10-week testing period. Significantly higher digestibility of dry matter, organic matter, protein and energy were noted in the raw vs. control groups for both kittens and adult cats, despite similar levels of intake. These changes may be attributed to structural changes in proteins following processing, alterations in gastrointestinal flora, or differences in ingredient quality among diets. In conclusion, there was neither an advantage nor disadvantage of the two raw feline diets when compared with the commercial heat-processed, control diet and both diets would be deemed nutritionally adequate for feline growth based on AAFCO feeding trials. The raw food diets were associated with higher digestibility and decreased fecal matter. Future research on methods to reduce pathogen load while minimizing processing of animal tissue proteins is recommended