effect of electron beam irradiation on degradability coefficients and ruminalpostruminal digestibility of dry matter and crude protein of some plant protein sources

effect of electron beam irradiation on degradability coefficients and ruminal- postruminal digestibility of dry matter and crude protein of soybean meal, canola meal and lathyrus sativus seed, irradiated at doses of 50, 100 and 150 kgy was investigated. ruminal degradability of dry matter and crude protein was determined by in situ method using two cannulated holstein heifers. ruminal- postruminal digestibility of dry matter and crude protein was determined by in situ (nylon bag)-in vitro (daisy digestor) techniques. data analyzed using sas software as randomized completely design and the treatment means were compared using tukey test. the results indicated that irradiation had no effect on dry matter, ether extract and ash content of feeds. in soybean meal, washout fraction and potentially degradable fraction of dry matter and crude protein was higher and lower at dose of 150 kgy irradiation than other treatments, respectively, and degradation rate constant and ruminal effective degradability of dry matter and crude protein was lower at all doses of irradiation than untreated soybean meal. in canola meal, irradiation at doses of 50 and 100 kgy decreased washout fraction and increased potentially degradable fraction of crude protein compared with untreated canola meal. in lathyrus sativus seed, only potentially degradable fraction of dry matter and crude protein was lower at dose of 150 kgy irradiation than untreated lathyrus sativus seed. ruminal digestibility of crude protein decreased in soybean meal at doses of 100 and 150 kgy irradiation and for canola meal at all doses of irradiation than untreated samples. total tract digestibility of crude protein decreased in soybean meal at dose of 150 kgy irradiation and for canola meal at all doses of irradiation than untreated samples. in lathyrus sativus seed, ruminal-postruminal digestibility and total tract digestibility of dry matter increased at doses of 100 and 150 kgy irradiation than untreated lathyrus sativus seed. postruminal digestibility and total digestibility of crude protein of lathyrus sativus seed increased at all doses of irradiation than untreated lathyrus sativus seed. base on the results of this study, beam electron irradiation had different effects on nutritional value of soybean meal, canola meal and lathyrus sativus seed but it improved protein quality of feeds especially in lathyrus sativus seed.