The disappearance of dry matter, nitrogen and amino acids in the gastrointestinal tract from Calliandra leaves

The total tract disappearance of dry matter (DM), nitrogen and amino acids in different Calliandra leaves harvested from Kenya and Zimbabwe were measu red using the mobile bag technique. In the mobile bag measurements, disappe arance was measured in the rumen in sacco, by pepsin-HCl hydrolysis in vitr o and in the intestine. The hydrolysis in the pepsin-HCl solution was desig ned to mimic digestion in the abomasum. The total tract disappearance of DM , nitrogen, and amino acids were generally low. The highest total apparent DM, nitrogen and total amino acid disappearance obtained were 425 (g/kg) 45 8 (g/kg total nitrogen), and 593 (g/kg amino acid), respectively. There wer e differences between the leaves in the disappearance of DM. nitrogen and a mino acids, and in the proportion of nutrients lost in the rumen, after pep sin-HCl hydrolysis and in the intestine. hlore DM, nitrogen, and amino acid s in the leaves from Kenya disappeared in the intestine in comparison to th e disappearance in leaves from Zimbabwe. The reasons far the differences be tween the nutritive values of the leaves is unclear but appears to be stron gly influenced by the stage of growth and conditions in which the plants we re grown. (C) 1999 Elsevier Science B.V. All rights reserved.