PSVI-32 The effects of varying amylose levels in different diets on digestibility and glycemic response in canines

Abstract

This study was conducted to compare the digestibility of pulse-based diets to grain-based diets based on varying levels of amylose and study how changes in digestibility impacts glycemic response in dogs. To establish glycemic response, six diets were formulated at an inclusion level of 20% available starch with varying amylose content. A grain-based diet was formulated using rice, while pulse-based diets consisted of smooth pea, wrinkled pea (4140–4 and Amigold varieties), faba bean, or lentil. Beagles (n = 8, 4 females, 4 males) were fed the 6 different test diets for 7 days in a randomized, cross-over, blinded design. At the end of each feeding period, fecal samples were collected and beagles were fasted overnight and subjected to a glycemic test (1g/kg of diet or glucose fed). Data collected were statistically analyzed using SigmaPlot 12.0 and significance was declared at P ≤ 0.05. Amylose levels of diets varied from 4.64% to 14.82% on a dry basis. The rice-based diet had the lowest amylose content, while the wrinkled pea (Amigold variety) diet had the highest amylose content. Following the collection of glycemic response and fecal data, repeated-measures, 1-way ANOVA’s were conducted. There were significant differences observed between diets based on peak glucose levels (mmol/L, P = 0.01). The rice diet had the highest peak in glucose, while the lentil-based diet had the lowest glucose peak. Significant differences were also seen between diets based on their digestibility (P < 0.001). Rice, lentil, faba bean and smooth pea-based diets had the highest levels of digestibility, while wrinkled pea varieties had decreased digestibility. Furthermore, varying amylose found in diets can be viewed as an impacting factor on glycemic response and digestibility. Incorporating pulses with higher amounts of amylose could be utilized in dog diets to promote a low glycemic response through decreased rates of digestibility.