The effects of drying and gamma irradiation on the nutritive value of laying hens exereta

The changes in the values of total nitrogen (N), in vitro crude protein digestibility (IVCPD), in vitro organic matter digestibility (IVOMD), in vitro digestible energy (IVDE), Crude fibre (CF) and cell-well constituents (NDF, ADF, ADL) for laying hens exereta were studied under the effects of: 1-two types of drying: a) drying at 175 deg for 10 minutes (D1); b) drying at 55 deg for 4 days (D2). 2-different doses of gamma irradiation (0, 10, 50, 100, 150 KGy). The results indicated that there was a significant (P<0.05) decrease in the values of NDF (by 8%), ADF (by 6%), CF (by 13%), IVCPD (by 13%), N (by 16%) and a significant increase in the values of IVOMD (by 12%) and IVDE (by 630 Kj/Kg DM) as a result of drying (D1) in comparison with drying (D2). A significant (P<0.05) decrease was observed in the values of NDF (by 5%), ADF (by 7%), CF (by 12%) and a significant increase in the values of IVOMD (by 13%) and IVDE (by 980 Kj/Kg DM) as a result of gamma irradiation treatment (100 KGy) in comparison with the control. There was no significant difference between doses 100 KGy and 150 KGy. Gamma irradiation had no effect on N, ADL and IVCPD values. Combined treatment (Drying D1 + 100 KGy) resulted in better effect in reducing the concentrations of CF, NDF and ADF and in increase the values of IVOMD and IVDE. (author). 26 refs., 3 tabs