Effect of consumption of uncooked (RS2) and retrograded (RS3) resistant starch on apparent absorption of magnesium, calcium, and phosphorus in pigs.

The aim of this investigation was to study the effect of uncooked (RS2) and retrograded (RS3) resistant starch on the size and site of the apparent absorption of magnesium, calcium, and phosphorus in swine. In an experiment with a parallel design, three groups of six piglets each consumed for two weeks a diet containing either glucose, RS2 or RS3. The piglets were cannulated at the end of the ileum which allowed estimation of the ileal and colonic mineral absorption. Urine, feces, and ileal digesta were collected for measurement of magnesium, calcium, and phosphorus. Dietary RS2, but not RS3, versus glucose reduced (p < 0.05) the total absorption of magnesium and calcium and the ileal absorption of phosphorus in the pig. Differences between species or in RS and/or mineral intake may explain why RS2 reduced the apparent absorption of magnesium and calcium in pigs in this study and raised it in rats in earlier studies.