Healthy Ageing Is Associated with Preserved or Enhanced Nutrient and Mineral Apparent Digestibility in Dogs and Cats Fed Commercially Relevant Extruded Diets

• Published in: Animals (Basel) Vol. 11; no. 7; p. 2127
• Main Authors: Schauf, Sofia, Stockman, Jonathan, Haydock, Richard, Eyre, Ryan, Fortener, Lisa, Park, Jean Soon, Bakke, Anne Marie, Watson, Phillip
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 17.07.2021; MDPI
• Subjects: Age; Age factors; ageing; Aging; Animals; Calcium; cat; Cats; Chronology; Diet; Dietary fiber; Digestibility; dog; Dogs; Energy; Essential nutrients; Extrusion; fat digestibility; High fat diet; Life expectancy; Life span; Low fat diet; Males; Nutrient deficiency; Nutrients; Nutrition; Nutrition research; Pets; Phosphorus; Physiology; protein digestibility; Proteins; total dietary fibre
• ISSN: 2076-2615; 2076-2615
• DOI: 10.3390/ani11072127

Age-related changes in gastrointestinal function have been reported in companion animals, but the impact on digestive efficiency remains uncertain. Healthy dogs (n = 37; 2.6–14.2 years) received four diets varying in total dietary fibre (TDF; 6–29%, as fed). Healthy cats (n = 28; 1–13 years) received four diets with two fat (10–12%; 17–18%) and TDF (9 and 12%) levels. In a crossover design, diets were provided over four consecutive 10-day cycles, including a 4-day faecal collection. Apparent crude protein (CP), ether extract (EE), TDF, calcium (Ca), and phosphorus (P) digestibilities were determined. The effect of age was analysed as a continuous variable in dogs and as differences between adult (1–5 years) and senior (7–13 years) cats. In dogs, EE digestibility was unaffected by age (p > 0.10). Dogs of 6–12 years had higher digestibility of CP (p = 0.032), TDF (p = 0.019), Ca (p = 0.019), and P (p = 0.024) when fed the 6% TDF diet. Senior cats had greater digestibility of TDF (p < 0.01) and Ca (p = 0.024) but had lower EE and CP digestibility with one diet (17% fat; 9%TDF) (age, p > 0.10; diet × age, p < 0.001). Healthy ageing was associated with preserved nutrient digestibility in dogs and cats within the age ranges studied. The effect of ingredient sources in senior cats warrants further investigation.