The Effect of a Complementary Feed Mixture oN Nutrient Digestibility Coefficients and Fermentation Processes in Dogs

The aim of the study was to determine the chemical composition of complementary feed mixtures (MPU) in the form of chews and pellets; to assess in vitro fermentation parameters using the gas test (gas production, volatile fatty acids, ammonia, pH, and organic matter degradation); and to estimate nutrient digestibility coefficients in dogs using the indicator method. In addition, correlations were determined between fecal excreted components and digestibility coefficients versus fermentation indices. The canine study was conducted in two phases: before (feeding exclusively a maintenance diet) and after 3 months of feeding the same maintenance diet combined with MPU. Dogs were fed the same commercial dry and wet food according to their energy requirements. MPU was administered according to the established dosage per kg of body weight. No effect of MPU was demonstrated on reducing nutrient digestibility. In contrast, MPU influenced fermentation processes: fecal pH and ammonia production decreased significantly, while the production of fermentative gases and the amounts of SCFAs and VFAs increased. The results confirm a beneficial effect of MPU on fermentation parameters through modulation of the canine gut microbiota, without affecting digestibility coefficients; therefore, MPU can be safely used as an additive to standard canine diets.