Po. Osuji et Aa. Odenyo, THE ROLE OF LEGUME FORAGES AS SUPPLEMENTS TO LOW-QUALITY ROUGHAGES - ILRI EXPERIENCE, Animal feed science and technology, 69(1-3), 1997, pp. 27-38
Supplementation of basal diets with multipurpose trees (MPTs) increase
s essential nutrients available to rumen microbes, increases rate of p
assage of particulate matter by 23-53% and of liquid matter by 9-43%.
Supplementing teff straw with graded levels of cowpea or lablab signif
icantly increased microbial N supply in calves. Supplements of Sesbani
a and Chamaecytisus sp, promoted higher N retention compared with unsu
pplemented roughage. The ILRI's work on evaluation of MPTs demonstrate
d that type, form and quantity affect microbe-MPT interactions and, co
nsequently, the utilization of the basal diet. Using gas production as
an index of fermentation, it was shown that Chamaecytisus palmensis (
Tagasaste) is fermented rapidly while Acacia angustissima is fermented
slowly by mixed ruminal microbes. Volatile fatty acid (VFA) analysis
showed that mixed ruminal microbes produced most (63.9 mu mol/ml) VFAs
from Sesbania sesban while A. angustissima fermentation produced the
least (15 mu mol/ml) amount at 12 h. Extracts of A. angustissima inhib
ited the growth of pure cultures of rumen bacteria (Ruminococcus albus
, Ruminococcus flavefaciens, Prevotella ruminicola and Streptococcus b
ovis). Multipurpose trees affect protozoal populations in sheep differ
ently. Sesbania sesban significantly (P < 0.04) increased while Acacia
cynophylla decreased the numbers of protozoa in Ethiopian highland sh
eep fed a basal diet of maize stover supplemented with various MPTs. M
ilk production and growth responses of cattle supplemented with MPTs o
r browses were variable. (C) 1997 Elsevier Science B.V.