Body weight was measured weekly for the first month and every four weeks thereafter until 43 weeks of age (unless identified, all week numerals indicate mice age). Food was changed biweekly and measured every two of four weeks' interval. Food intake was obtained by subtracting remaining food, including any spilled food in cages, from a weighed aliquot for a period of two weeks. Energy intake was calculated on the basis of 4.73kcal/g for the HFD and 3.85kcal/g for the LFD (caloric values obtained from Research Diets, Inc.). Body composition (fat and fat-free mass) was determined in vivo using quantitative magnetic resonance (QMR) (EchoMRI™ 3-in-1 v2.1; Echo Medical Systems, Houston, TX) at 8, 23 and 43 weeks of age as described (14 (link)). Caloric content of the change in body mass was computed at 1.8 kcal/g for fat-free tissue and 8 kcal/g for fat tissue (15 (link)).
Moribund mice, including mice with ulcerative dermatitis or similar skin lesions (n=29) or those unable to eat/drink (one female), were euthanized in accordance with university and IACUC policies. One male mouse died spontaneously during the study. A total of 23 female and 8 male mice were dead or removed prior to 10 months of age; thus, 554 mice were included in the data analysis (255 HFD females, 269 HFD males, 15 LFD females and 15 LFD males).
Moribund mice, including mice with ulcerative dermatitis or similar skin lesions (n=29) or those unable to eat/drink (one female), were euthanized in accordance with university and IACUC policies. One male mouse died spontaneously during the study. A total of 23 female and 8 male mice were dead or removed prior to 10 months of age; thus, 554 mice were included in the data analysis (255 HFD females, 269 HFD males, 15 LFD females and 15 LFD males).
