Comparative nutritive evaluation of native Panicum maximum, selected tropical browses and their combinations using in vitro gas production technique.

In vitro gas production technique was used to predict the nutritive values of native Panicum maximum, Gliricidia sepium, Leucaena leucocephala, Moringa oleifera and Flemingia macrophylla, as well as assess and compare the supplementation effects of the selected tropical browses on native Panicum maximum. Evaluation parameters were gas production volumes, gas production constants, methane production, predicted metabolizable energy, organic matter digestibility and short chain fatty acid production. Gas production from Panicum maximum was significantly (P<0.05) lower than from any of the experimental browses, or their combinations with Panicum maximum, at all incubation periods except at 12 hours. Significantly (P<0.05) highest gas volume (37.667 ml/ 200 mgDM) was recorded for Moringa oleifera. All the in vitro gas production characteristics were observed to vary significantly (P<0.05) across all the treatments. Panicum maximum produced the least amount of methane (11.33 ml) while the highest volume of 14.00 ml was recorded for both Gliricidia sepium and Moringa oleifera. Overall, the methane production figures indicate that combining Panicum maximum with any of the browses increased methane production above that of Panicum maximum only, but lowered it with respect to what obtained for the corresponding browse. Significant (P<0.05) differences were observed in OMD, ME and SCFA across all the treatments. Generally, the browses had significantly (P<0.05) higher values than Panicum maximum. It was concluded that combining Panicum maximum and Moringa oleifera at 60:40 improved nutrient availability, OMD, ME and SCFA, and at the same time ameliorates the twin problems of energy loss to ruminants and global warming associated with methane production in ruminant nutrition.