119 Awardee Talk: A Matter of the Heart: The Use of Pulses in Canine and Feline Nutrition

In the pet food industry, the popularity of plant-based protein sources has risen as consumer demand for grain-free and novel protein sources increase. However, minimal research has been conducted as regards use of pulses and their effects on acceptability and digestibility in canine and feline nutrition. In addition, market shift towards grain-free and pulse-rich diets has presented concerns about the suitability of pulses as viable protein sources. In July 2018, the FDA published a press release discussing a potential link between diets containing legumes and the development of dilated cardiomyopathy (DCM) in dogs. As such, part of our research program has focused on the 1) characterization of the macronutrient composition and protein quality of plant-based protein sources, 2) evaluation of the effects of plant-based protein sources in extruded canine and feline diets on macronutrient digestibility, and modulation of fecal microbiota and metabolites, and 3) determination of the longitudinal effects of high pulse inclusion in diets on taurine status in dogs. Pulse ingredients contained approximately 20% crude protein, and had methionine or tryptophan as the first-limiting amino acids using the precision-fed cecectomized rooster assay. When incorporated in canine and feline diets, pulses did not result in negative effects on macronutrient digestibility or fecal scores. However, shifts in fecal microbial and metabolites were observed in animals fed pulse-based in contrast with animal-based protein diets. The inclusion of 45% green lentils in extruded diets did not cause decreased plasma or whole blood taurine or methionine levels. Additionally, excess taurine was not depleted from these animals in the urine or feces. Taurine status was considered normal in these dogs, despite changes in fecal bile acid concentrations and microbiota. Although we are currently carrying out further research projects investigating potential association of pulse rich diets and canine DCM. Current research findings from our laboratory suggest the inclusion of pulses may not be the causative factor. The use of plant-based proteins as ingredients in canine and feline diets not only meet consumer demand but also provide a valuable, safe, and nutritionally adequate alternative to traditional protein sources.