The combination of dietary fiber and time period affect ileal digestibility marker concentration in growing pigs

This study was conducted to investigate if the concentration patterns of digestibility markers (DMr) are influenced by dietary fiber (Diet), ileal digesta collection day (Day), and time period (TP). Eighteen barrows fitted with a T-cannula at the end of the ileum were used in a 2-period randomized complete block design. Three corn-soybean meal-based diets were formulated with corn starch (CS), corn bran (CB) or oat bran (OB) at 100 g/kg. All 3 diets contained 3 DMr, which were chromic oxide (Cr), titanium dioxide (Ti), and acid-insoluble ash (AIA). The ileal digesta was collected every 3 h between 09:00-21:00 h with 4 TP on each of the 3 day. Due to the interaction between Diet and TP, diet comparison within TP using appropriate standard error of the difference of two means were discussed. The Ti or AIA concentration on Day 1 was lower (P < 0.05) than that on Day 3, while there was no difference between Day 2 and Day 3. The Cr concentration was not affected by the Day. The distribution of Cr concentration in ileal digesta of pigs fed CS, CB and OB was similar to that of Ti and AIA irrespective of TP. When comparing OB and CB, OB had greater (P < 0.05) Ti and AIA concentrations than CB at TP 2, 3 and 4, but OB had similar DMr concentration with CB at TP 1. In conclusion, the Day had limited effect on DMr concentration; the three DMr moved synchronously in digesta irrespective of TP; and the Ti and AIA concentrations varied over the OB and CB at TP 2, 3 and 4, but not at TP 1.