Abstract
To be more sustainable, the pet food industry could increase the inclusion of animal byproducts from the human food chain and fish hydrolysates have been reported to benefit dogs' health. However, there is limited research on the impact of alternative marine hydrolysates in dog food. The current study evaluated the effects of including shrimp hydrolysate as a replacement for wheat gluten (experimental diet) in an extruded complete diet (control diet) on diet palatability, intake, digestibility, fecal characteristics and metabolites, oral volatile sulfur compounds (VSC), and coat quality in dogs. The palatability of diets was assessed in a 2-bowl test, conducted with 12 healthy adult Beagle dogs. No differences were observed in the first approach, first taste, or intake ratio. A randomized block design lasting 12 wk was performed with 12 dogs distributed into 6 blocks, according to sex and body weight; one dog from each block was randomly allocated to each diet. Fecal characteristics and metabolites were measured in weeks 0, 4, 8, and 12, VSC and coat quality in weeks 4, 8, and 12, and apparent total tract digestibility (ATTD) of nutrients and energy in week 12. The inclusion of shrimp hydrolysate did not affect intake, but increased fecal output (dry matter, DM, basis, P < 0.05). Fecal butyrate concentration was lower (P < 0.05) in dogs fed the experimental diet. The inclusion of shrimp hydrolysate did not affect ATTD of nutrients and energy, and VSC. Both diets promoted high coat quality. The experimental diet decreased gloss and general evaluation scores in week 4 (P < 0.05), but improved scale scores in weeks 4 and 12 (P < 0.05). Overall, the findings indicate the potential of including shrimp hydrolysate in diets for dogs, fostering a more sustainable industry.