Nutrient Digestive Bypass: Determinants and Associations with Stool Quality in Cats and Dogs

• Published in: Animals (Basel) 2024-09, Vol.14 (19), p.2778
• Main Authors: Jackson, Matthew I, Wernimont, Susan M, Carnagey, Kristen, Jewell, Dennis E
• Format: Article
• Language: English
• Subjects: Age; Animals; Carbohydrates; cat; Colon; Dietary fiber; digestibility; dog; Dogs; Feces; macronutrients; Metabolism; Motility; Nutrients; Nutrition; Pet food; Physiological aspects; Proteins; Rabies; Requirements; stool
• ISSN: 2076-2615; 2076-2615
• DOI: 10.3390/ani14192778

The effect of digestive bypass macronutrients and age on stool quality (moisture and firmness) in dogs and cats is not well understood. Data were analyzed from digestibility tests ( = 2020, 361 dogs and 536 cats) including dry and wet product types. Both food and feces were measured for moisture and nutrients according to standard protocols; stool firmness was graded. Linear mixed modeling was used to evaluate the associations between nutrient bypass, age and stool quality. Bypass protein increased stool moisture (dog, cat < 0.0001) and decreased firmness (dog = 0.01, cat < 0.0001), while bypass fiber decreased stool moisture and increased firmness (dog, cat < 0.0001 for both). Both species manifested a negative quadratic effect of advanced age on stool firmness (dog < 0.0001 and cat = 0.02). However, the association of advanced age (quadratic effect) with metabolizable energy required to maintain body weight was different between species; dogs had a positive association ( = 0.028), while it was negative for cats ( < 0.0001). Taken together, these data may aid in the development of food formulations for companion animals, which can better meet changing nutritional needs across life stages.