Abstract
Human-grade pet foods are believed to be of higher quality than traditional pet foods, but little research has been conducted on them to date. Therefore, our objective was to determine the apparent total tract digestibility (ATTD) of human-grade pet foods and evaluate their effects on stool characteristics, serum metabolites, and hematology of dogs. Twelve dogs (mean age = 5.5 ± 1.0; BW = 11.6 ± 1.6 kg) were used in a replicated 4×4 Latin square design. The diets included: 1) Chicken and Brown Rice Recipe (extruded; Blue Buffalo); 2) Roasted Meals Tender Chicken Recipe (fresh; Freshpet); 3) Beef & Russet Potato (human-grade; JustFoodForDogs); and 4) Chicken & White Rice (human-grade; JustFoodForDogs). Each period consisted of 28 d, with a 6-d diet transition phase, 16 d of consuming 100% of the diet, a 5-d phase for total and fresh fecal collection, and 1 d for blood collection. All data were analyzed using the Mixed Models procedure of SAS 9.4. Dogs fed the extruded diet had a higher (P < 0.05) daily food intake (dry matter basis; DMB) and fecal output (as-is and DMB) compared with dogs fed fresh or human-grade dog foods. There were no differences in fecal pH or scores across diets, but ATTD of dry matter (DM), organic matter (OM), and acid-hydrolyzed fat (AHF) were greater (P < 0.05) for dogs fed the human-grade diets than those fed the fresh diet. Likewise, DM, OM, and AHF ATTD were greater (P < 0.05) in dogs fed the fresh diet than those fed the extruded diet. The majority of serum metabolites and blood cell counts of dogs fed all diets were within the reference ranges for adult dogs, with few treatment differences. In conclusion, the human-grade foods tested were shown to be highly digestible and maintained stool characteristics, serum chemistry, and complete blood count in adult dogs.