A preliminary study on determination of ileal digestibility of feed nutrients with duodenal mobile nylon bag technique (MNBT) in ileo-rectally anastomosed pigs.

The use of MNBT for determination of ileal digestibilities of DM and CP in 9 tested feeds was studied.Bags,measuring 25×40mm2 and containing 1g feed samples,were introduced into the pig gastrointestinal tract through a duodenal cannula,and recovered in the ileal digesta 12～24 hour later on. 1.The disappearances of DM and CP(nitrogen×6.25)from the bags was compared with in vivo apparent and true ileal digestibilities,determined by ileal digesta collection method in ileorectal anostomosis pigs.The CP digestibilities in all of the tested feeds determined by MNBT were signficantly(P0.01 or P0.05)higher than apparent those determined by ileal digesta collection,but similar to the results of the ture ileal digestibilites.There were similar values of DM digestibilities determined by the two methods. 2.There were no significant differences of the ileal digestibilities in tested samples between the washed and unwashed bags, and between 4 minute and 8 minute washing bags.The digestibilities determined under different prepsin concentrations(0.03%,0.07% and 0.1%) were also not significant. 3.The ileal digestibilities in the tested samples,exception of fish meal,detenmined by MNBT were not effected by the different predigestion times(2.5h and 4h). According to the results,it is concluded that deodenum mobile nylon bag technique with ileo-rectal anastomosis pigs is a rapid and less cost method for determining ileum digestibilities of feed nutrients.