Effects of high-fat diet at two energetic levels on fecal microbiota, colonic barrier and metabolic parameters in dogs.. feces metagenome

In studies that have investigated the consequences of HFD on gut microbiota, it was difficult to distinguish the effects driven by increased calorie intake from those driven by increased body weight (and increased body fat) because the HFD was usually administered at a hyperenergetic level (or even ad libitum). The current study was designed to dissociate the effects of a HFD from those subsequent to a body weight gain on the microbiota, the intestinal barrier and the host physiology (inflammatory and metabolic variables).To reach this objective, a high-fat diet (35% fat as fed, 4923 kcal/kg) was given for 8 weeks to 24 adult healthy Beagle dogs. 8 of them have received the food at maintenance energy level, and the other ones at 150% maintenance energy levels.BW and BCS were recorded each week. Blood samples were carried out after a 24-hour unfed period, and postprandially following a feed challenge test, before and at the end of 8-week period. Colonic biopsies were performed, and diet digestibility was determined, according to the same time-schedule. Colonic permeability was determined at baseline, and after 4 and 8 weeks. Fresh fecal samples were collected at baseline then every two weeks. At every time point, one sample per dog was collected immediately after spontaneous defecation and frozen, without further treatment, at -80C.