Rumen Degradation Kinetics of Feedstuffs as Estimated by in situ and in vitro Gas Production Techniques
2011
Shete, S. M. | Tomar, S. K. | Sirohi, S. K. | Thakur, S. S.
The rumen fermentation kinetics of thirteen feed ingredients was studied by two techniques. The organic matter degradability of the feedstuffs was estimated by nylon bag technique (NBT) while the gas production was estimated by in vitro technique (IVGPT). The OM degradation and gas production kinetic parameters were calculated by first order exponential model. The rapidly soluble ‘a’ fraction was maximum in mustard cake (52.2%) and minimum in maize grain (10.0%) and wheat straw (8.7%). Potentially degradable ‘b’ fraction was higher in grains (66.1% and 76.3%) than in cakes and fodders. The rate of degradation was higher in cakes and grains (except maize grain) than in fodders. The potential gas production was higher in grains (79.5 and 77.3 ml). The rate of gas production was higher in cakes than grains and fodders. The correlation coefficient (r) between OM degradability by NBT and gas production by IVGPT was more than 0.9 for most of the feed ingredients showing a greater degree of linear correlation between them. The linear regression of OM degradation kinetic parameters on extent and rate of gas production was significant (P < 0.01). Regression equations were derived between extent of gas production (bgₐₛ) and potential OM degradation (b); and rate of gas production (cgₐₛ) and instantly soluble OM fraction (a), rate of OM degradation (c) and effective OM degradability (EOMD). It was concluded that NBT can be replaced by IVGPT to assess OM degradation kinetics of feedstuffs.
显示更多 [+] 显示较少 [-]