In Vitro gas production assessement of Panicum maximum incubated with Leucaena leucocephala at varying proportions to predict the nutritional value for ruminants

The inclusion of multipurpose trees with grass such as Panicum maximum in the diet of ruminants may enhance productivity. Thus, the study was carried out to determine the proximate composition, in vitro gas production characteristics and parameters of Leucaena leucocephala and Panicum maximum at varying proportions. Five diets were formulated such that Panicum maximum was substituted with Leucaena leucocephala at different ratio: T1 (100% Panicum maximum), T2 (100% Leuceana leucocephala), T3 (50% P. maximum + 50% L. leucocephala), T4 (75% P. maximum + 25% L .leucocephala) and T5 (25% P. maximum + 75% L. leucocephala). Data were subjected to analysis of variance. Values obtained for dry matter (34.43 –35.95g/100g) decreased with the increased inclusion of Leuceana leucocephala in the diets. The crude fiber values (14.33 – 30.75g/100g) also followed the same trend while crude protein (CP) content (10.70 – 26.78g/100g) increased the inclusion of Leucaena leucocephala in the diets. There were significant (P < 0.05) differences in the treatment means of organic matter digestibility (OMD 31.93 – 37.07%), Metabolisable energy (ME 3.62 – 4.33 MJ/kgDM), short chain fatty acids (SCFA 0.04 – 0.16mL) and methane (ME 1.00 – 2.50 mL).The values (2.00 – 4.67 ml/200mgDM) obtained for immediate soluble 'a' was significantly (P < 0.05) different among the treatments. The extent of gas production (a+b) ranged from 2.00 – 4.67 mL/200mgDM, T1 (100% Panicum maximum) recorded the lowest while highest was observed in T2 (100% Leucaena leucocephala). The insoluble but degradable fraction 'b'ranged from 2.67 – 5.67ml/200mgDM, while the rate of gas production 'c' ranged from 0.04 – 0.14ml/hr. In conclusion, the enhanced values of crude protein, OMD, SCFA, and ME in the Panicum maximum and Leucaena leucocephala mixture indicate that the diets is able to meet the nutrients requirements of small ruminants in the tropics especially during the dry season.