was consumed. The W-HAMS, W-HAMSB, and W-HAW diets also resulted in greater cecal acetate, propionate, butyrate, and total SCFA pools than in the C-LAMS group, although these were not always signiﬁcant. The concentrations of SCFA in the cecum were not signiﬁcantly changed apart from propionate, which was signiﬁcantly higher for the W-HAW group than all other groups. The relative proportions of individual SCFA in the cecum also changed in response to diet. The percentage of total SCFA as acetate was signiﬁcantly lower (and the percentage of butyrate signiﬁcantly higher) for the W-HAMSB group relative to the W-LAW and W-LAMS groups and the percentage of propionate was signiﬁcantly higher for the W-HAW group relative to other groups. In the colon, signiﬁcant differences in SCFA pools in response to treatment were found for propionate, which was signiﬁcantly higher in the W-HAW group than in the C-LAMS and W-LAMS groups. Colonic concentrations of acetate, propionate, and total SCFA differed signiﬁcantly. The acetate concentration was lower in the W-HAMSB group than in the C-LAMS and W-HAW groups. The propionate concentra- tion was greater in the W-HAW group than in all other groups and total SCFA was greater in the W-HAW group than in the W- HAMS and W-HAMSB groups. The concentrations of hepatic portal venous acetate and butyrate were signiﬁcantly higher in rats fed W-HAMS and W-HAMSB, respectively, than in those fed W-LAMS, and propionate concentrations were signiﬁcantly higher in rats fed W-HAMS and W-HAW. Effects of including different sources of starch in a Western diet moderate in protein and fat on individual and total SCFA levels in cecal and colonic digesta, and hepatic portal vein plasma of rats1 C-LAMS W-LAMS W-HAMS W-HAMSB W-LAW W-HAW TABLE 2 Variables Cecum SCFA Pool, mmol Acetate Propionate Butyrate Total Concentration, mmol/kg tissue Acetate Propionate Butyrate Total Percentage of total, % Acetate Propionate Butyrate Colon SCFA Pool, mmol Acetate Propionate Butyrate Total Concentration, mmol/kg tissue Acetate Propionate Butyrate Total Percentage of total, % Acetate Propionate Butyrate Portal vein SCFA Concentration, mmol/L Acetate Propionate Butyrate Total Percentage of total, % Acetate Propionate Butyrate 94 6 14a 16 6 2a 62 6 7a 178 6 22a 75 6 6 13 6 1a 51 6 4 144 6 9 52 6 2a 9 6 1a 35 6 2a 57 6 7 9 6 1a 24 6 4 93 6 10 49 6 4a 8 6 1a 21 6 4 81 6 7ab 60 6 3ab 10 6 1a 25 6 3 399 6 14ab 52 6 6ab 223 6 30ab 674 6 43a 60 6 3 8 6 1a 32 6 3 67 6 11a 11 6 2a 39 6 6a 121 6 18a 65 6 7 10 6 1a 37 6 4 117 6 11 56 6 2a 9 6 1a 31 6 2a 56 6 4 8 6 1a 26 6 3 94 6 8 47 6 3ab 7 6 1a 22 6 2 78 6 5ab 60 6 2ab 9 6 1a 27 6 2 338 6 23a 39 6 6a 166 6 15a 542 6 40a 63 6 2 7 6 1a 30 6 1 188 6 32b 33 6 4b 136 6 26b 377 6 56b 72 6 8 13 6 1a 50 6 5 143 6 10 50 6 2a 9 6 1a 35 6 3a 65 6 7 12 6 2ab 28 6 7 110 6 14 42 6 3ab 7 6 1a 17 6 3 70 6 5a 62 6 3a 10 6 1a 23 6 3 528 6 66b 71 6 10ab 264 6 39ab 863 6 91b 62 6 3 8 6 1ab 30 6 3 158 6 18b 32 6 5b 167 6 28b 369 6 51b 59 6 3 12 6 1a 61 6 6 135 6 9 44 6 1b 9.0 6 1a 44 6 1b 59 6 5 14 6 2ab 45 6 6 123 6 11 30 6 2b 7 6 1a 23 6 3 63 6 5a 49 6 2b 11 6 1a 36 6 2 465 6 36ab 95 6 14b 354 6 38b 914 6 81b 52 6 2 10 6 1ab 38 6 1 107 6 15ab 16 6 2a 69 6 7a 200 6 24ab 78 6 7 12 6 1a 51 6 4 146 6 11 53 6 1a 8 6 0a 35 6 1a 48 6 7 9 6 1a 26 6 7 87 6 15 43 6 5ab 8 6 1a 24 6 5 78 6 11ab 57 6 3ab 10 6 1a 28 6 3 405 6 43ab 59 6 11ab 204 6 29ab 668 6 78ab 62 6 2 8 6 1ab 30 6 1 151 6 22b 42 6 7b 104 6 27b 308 6 47b 80 6 10 22 6 3b 52 6 9 161 6 15 49 6 3ab 14 6 2b 32 6 4a 78 6 14 21 6 4b 33 6 7 137 6 18 57 6 7a 15 6 2b 27 6 5 103 6 11b 55 6 4ab 14 6 1b 26 6 4 449 6 42ab 93 6 13b 251 6 61ab 793 6 89ab 58 6 4 12 6 1b 30 6 5 1 Values are mean 6 SEM, n = 9–10. Labeled means without a common letter differ, P , 0.05. C-LAMS, control diet containing low amylose maize starch; W-HAMS, Western diet containing high amylose maize starch; W-HAMSB, Western diet containing butyrylated high amylose maize starch; W-HAW, Western diet containing high amylose wheat ﬂour; W-LAMS, Western diet containing low amylose maize starch; W-LAW, Western diet containing low amylose wheat ﬂour. Colonic effects of resistant starches 835