Chiang Mai Journal of Science

Three crop residues and five roughages were selected to evaluate nutritive value using the in vitro gas production technique. The rumen mixed microbe inoculums were taken from fistulated Brahman-Thai native crossbred steers. The treatments were   1) water hyacinth (Eichhorunia crassipes Solms), 2) kraphanghom (Paederia foetida Linn), 3) corn stover (Zea mays),  4) cassava hay (Manihot esculenta Crantz), 5) sugarcane top (Saccharum officinarum Linn), 6) Chinese spinach (Amaranthus viridis L.), 7) rice straw (Oryza sativa) and 8) cavalcade hay (Centrosema pascuorum cv. Cavalcade). The treatments were assigned in order to completely randomize design (four replications). The results indicated that soluble gas fraction (a; -2.40, -20.31, -11.96, 0.49, -8.22, -0.99, -16.53 and -2.93 ml, respectively), fermentation of insoluble fraction (b; 88.49, 120.31, 111.96, 79.02, 108.62, 76.34, 116.63 and 101.41 ml, respectively ), rate of gas production (c; 0.014, 0.075, 0.052, 0.029, 0.035, 0.028, 0.036 and 0.040 %/h, respectively) and potential of extent of gas production (|a|+b; 90.89, 140.63, 123.07, 78.53, 117.24, 77.33, 133.07 and 104.34 ml, respectively) were significantly different (P<0.01) between treatments. These results implied that kraphanghom, rice straw, corn stover, Chinese spinach and cavalcade hay are highly digestible in the rumen. Importantly, crops residues and selected roughages are abundant and available for feeding the ruminants in dry season. These nutritive values provides helpful consideration when developing ruminant production systems.