107 - Restricted Feeding and Weight Loss Positively Change Fecal Microbiota Populations of Obese Dogs

Abstract: Canine obesity negatively influences health and well-being and appears to negatively modify gastrointestinal microbiota populations. Restricted feeding of a specially formulated diet and consequent weight loss may be used to improve health and modify gastrointestinal microbiota. In this study, we aimed to determine the effects of restricted feeding and weight loss on fecal microbiota populations of obese dogs. All procedures were approved by the University of Illinois IACUC prior to experimentation. Twenty-four obese spayed female dogs (BW = 15.2±1.7 kg; BCS = 8.7±0.4; age = 7.2±1.6 y) were used in a 24-wk weight loss study. A control (OR) food was fed during a 4-wk baseline to identify intake needed to maintain BW. After baseline (wk 0), dogs were allotted to one of two diets: OR or a test (FT) diet and then fed to lose 1.5% BW/wk. Fecal samples were collected at wk 0, 4, 8, 12, 16, 20, and 24 for microbiota and metabolite analyses. Fecal microbiota data were evaluated using QIIME2 and Mixed Models procedure of SAS, with P< 0.05 considered significant. Alpha-diversity was affected by diet and weight loss, with dogs fed OR having a greater alpha-diversity than those fed FT. Weight loss increased alpha-diversity (wk 16, 20, and 24 > wk 0 and 4). Beta-diversity, as assessed by weighted and unweighted PCoA plots, showed separation between dietary groups and between wk 0 and all the other time points after wk 8. Weight loss increased fecal Allobaculum and Ruminococcus torques. Weight loss also increased fecal Bifidobacterium, Faecalibaculum, Parasutterella in dogs fed both diets, but greater in dogs fed OR. Weight loss decreased fecal Collinsella, Turicibacter, Blautia, Ruminococcus gnavus, Faecalibacterium, Peptoclostridium in dogs fed both diets, but greater in dogs fed OR. Our data demonstrate that restricted feeding and weight loss alter fecal microbiota of obese dogs.