Absorption of Minerals and Retention Time of Dry Matter in the Gastrointestinal Tract of Broilers

Six-wk-old male broilers (Hybro), on a corn and soybean meal diet, were used to estimate the mean retention time (MRT) of DM in successive parts of the gastrointestinal (GI) tract and to determine the site of absorption of minerals (Na, K, Ca, and Mg). The main site of absorption of these minerals in the GI tract was between the lower duodenum and the lower jejunum. The apparent absorption of Na continued in the ileum and rectum, and secretion of K, Ca, and Mg was observed in the rectum. Between the lower duodenum and the lower jejunum, DM was retained about 70 min (one-quarter of the MRT in the whole GI tract).