ffect of irradiation on ruminal disappearance of dry matter and crude protein, and in vitro digestibility of canola meal

This research was conducted to evaluate the effects of electron beam (EB) and gamma ray (GR) radiations at doses of 25, 50 and 75 kGy on ruminal degradation kinetics of dry matter (DM) and crude protein (CP), and in vitro digestibility of canola meal (CM). The nylon bag technique and in vitro two step method were used for this aim. GR decreased ruminal degradability of DM (P<0.05), but EB had no effect on this trait (P>0.05). The ruminal degradation of CP was reduced by irradiation (P<0.05). In this case the efficacy of GR was more than EB (P<0.05). In vitro digestibility of CM was increased by irradiation (P<0.05). With increasing dose of GR and EB, the value of in vitro DM digestibility increased linearly (P<0.05). The effects of EB and GR on increasing of this trait were the same (P>0.05) The results of this study showed greater effects of GR than the EB in reducing the ruminal degradation of DM and CP, while the in vitro digestibility of CM was equally affected by these ionizing radiations.