رضا فیضی
علی محرری

Twenty-four (Baluchy) wethers were used in a complete raidomized design to measure voluntary intake and digestibility of corn silage fed alone (C diet) treated with urea at ensiling [%11 and %9 crud protein ( D and E diet respectively)] or blended with dairy cattle waste and ensiled [% 11 and %9 crud protein (A and B respectively)]. A three-period feeding schedule was used consisting of adjustment, preliminary and restricted intake period which included collection of feces. Wethers were fed individually in metabolic cages, which facilitating separate collection of feces. During the collection period animals were fed twice daily, and had access to water at all times except during the 2-hr feeding periods. The coefficients of apparent digestibility DM, OM, E, CP, CF, EE, NFE, TDN and D-Value for C diet were 63.14, 67.46, 60.09, 41.58, 58.47, 74.46, 73.43, 62.17 and 61.09 respectively. There were statistically differences between C diet and average of other diets for digestible CF, NFE, TDN and D Value (P<0.01). The refused feed and feces were weighed, sampled and frozen for subsequent analysis. The results from voluntary dry matter intake trial showed different between groups A,B and D,E diets with 663, 759 and 1083, 1125 gram per day, respectively (p<0.05). Voluntary dry matter intake C diet was 1017 gram per day, that hadn't significant difference, with B, D, E diets except with A diet (p<0.05). Apparent digestibility of dry matter (DM), organic matter(OM), encrgy(E), crude protcin(CP), crude fiber(CF), ether extract(EE), nitrogen free extract (NFE), total digestible nutrient(TDN) and D-Value for deits containing dairy cattle waste (A,B) and deits containing urea (D,E) were 56.25, 59.22, 54.35, 33.23, 62.78, 56.85, 60.29, 50.66, 48.93 and 65.47, 68.73, 63.19, 41.77, 68.08, 66.90, 71.45, 61.93, 59.87 respectively. There were statistically differences between groups A,B and D,E diets, for all parameters except for digestible CP, CF and EE (p<0.05).