Sf09 028

C57BL/6J and Gpr43^−/−age and sex-matched male mice of 6–8 weeks old (backcrossed to C57BL/6J > 13 generations) were obtained from Monash Animal Services and housed under specified pathogen-free (SPF) conditions in Monash University Animal Research Laboratories. Germ-free (GF) male C57BL/6J mice at 7 weeks old were obtained from Walter and Eliza Hall Institute of Medical Research Animal Facility. Following transportation, mice were acclimatized for a minimum period of 7 days before use. Mice were housed in a 12-hour light-dark cycle in a temperature controlled environment with free access to food and water. Where indicated, mice were supplemented with 200mM acetate in the drinking water, or removed from their normal chow and fed either control diet (Ctrl; AIN93G, consisting of 4.7% crude fibre; Specialty Feeds) or no fibre diet (NF; SF09-028, consisting 0% fibre, modified from AIN93G) for 2 weeks prior to experimentation. All animal experiments were approved by the Monash University Animal Ethics Committee.

Adult mice were provided with either an experimental control diet (CON; AIN93G diet with 4.7% dietary fiber content; irradiated; SF09-091, Specialty Feeds) or a no-fiber diet (NF; modified AIN93G diet with 0% dietary fiber content; irradiated; SF09-028 Specialty Feeds) for two weeks ad libitum. Details of the diets can be found in Supplemental Table 1. Mice were fed experimental diets for an additional one week for experiments utilizing the DSS model of intestinal inflammation.
To supplement acetate in the daily intake, 200 mM of sodium acetate (Sigma) in was added to the drinking water and mice had access to it ad libitum, as per previous studies (7 (link), 8 (link)). Acetate was supplemented into the drinking water in combination with the diet regime and refreshed twice every week. Control mice that received no supplementation of acetate were provided with normal drinking water.

As indicated, breeding pairs and nursing dams were administered a zero-fibre diet (SF09-028, Specialty Feeds, Glen Forrest, Australia) or high fibre diet (7.5% Inulin, 7.5% Pectin SF15-086, Specialty Feeds). Pups born from respective breeding pairs were reared on this special diet for the duration of the experiment. All foods were autoclaved or irradiated prior to feeding for sterility.
Unless otherwise stated, mice were maintained on a meat-free rat and mouse standard diet. Other than the specified dietary alterations, paired diets in each experiment were designed to be otherwise nutritionally equivalent. Mice were administered foods ad libitum for the duration specified in each experiment.