Intestinal digestibility of enriched-protein fodders measured by mobile bag incubated with or without pepsin-HCl and three-step techniques

Abstract

Ruminal, intestinal and total tract digestibility of dry matter (DM) and crude protein (CP) of leucaena (Leucaena leucocephala), Madras thorn (Pithecellobium dulce) and moringa (Moringa oleifera) fodders were measured in this study, using nylon bag and mobile bag techniques. Three cattle were fitted with permanent rumen and duodenal cannulae. Intestinal digestibility was measured using the mobile nylon bag (MNB) technique with or without incubation in a pepsin-HCl solution, and a three-step in vitro technique. The rate of ruminal disappearances of DM and CP, and the potential degradation of CP from nylon bags of both Madras thorn and moringa fodders were significantly higher than that for leucaena fodder. Potential degradation (A+B) values of CP were 45.6%, 54.2% and 52.8% for leucaena, Madras thorn and moringa fodders, respectively. Average DM and CP digestibility in the intestine and total tract for both Madras thorn and moringa fodders were significantly higher than for leucaena fodder. Average digestibility of DM and CP in the intestine and total tract measured using MNB without pepsin-HCl solution was significantly lower than with pepsin-HCl and with the three-step methods. These data suggest that the results of in vivo and in vitro methods for estimating intestinal digestibility are similar, though in all methods the incubation in a pepsin-HCl solution is necessary.

Keywords: Intestinal digestibility, protein fodder, mobile nylon bag, a three-step technique