Iv. Nsahlai et al., THE RELATIONSHIPS BETWEEN GAS-PRODUCTION AND CHEMICAL-COMPOSITION OF 23 BROWSES OF THE GENUS SESBANIA, Journal of the Science of Food and Agriculture, 65(1), 1994, pp. 13-20
This study evaluated the differences in the gas produced by Sesbania a
ccessions and related gas production to macro-constituents and tannin
content of the browse species. Fresh samples were incubated in triplic
ate (about 200 mg per syringe) in a medium prepared from sieved rumen
liquor harvested from two rumen-fistulated cows fed native pasture hay
ad libitum and 2.0 kg cottonseed cake per head per day. Sesbania spec
ies had similar rates of gas production but differed (P < 0.001) in th
e volume of gas produced. The ranking order for gas production was S g
randiflora > S sesban > S keniensis > S goetzei. There was little vari
ation in the gas production parameters within S grandiflora and S goet
zei. But the variation was large within S sesban. Regression analysis
showed that the rate of gas production was negatively affected (P < 0.
025) by the lignin content of the browses, but the volume of gas produ
ced was negatively related to the neutral detergent fibre, hemicellulo
se, lignin and insoluble proanthocyanidins content of browses. Cluster
analysis showed a broad agreement between gas production constants, m
acro-constituents and tannin contents in classifying accessions into h
igh or low nutritive value groups.