Nutritive Value Index of Fungal Treated Wheat Straw.

Wheat straw was inoculated with wheat grain spawns of two species of Pleurotus fungi (coded: F-77 and H-82), at a rate of 3.5-kg spawn per 100-kg straw (fresh weight basis). The inoculated straw packed in the plastic bags and incubated in a fermentation room at 25 "5"C and 65 "5, relative humidity. After 17 days of spawning and before fruiting body formation, half of the bags were removed from the fermentation room. The bags contained treated straw, was opposed to sun drying and the dried straw was stored for the in vivo experiments. For the remainder of the bags, solid-state fermentation was allowed for seven weeks during which the fruiting bodies were harvested two times, and then they were removed from the fermentation room, dried and used for the experiment. In a feeding trial, in vivo digestibility and voluntary intake were determined in sheep and cattle, where the dietary treatments were: 1) untreated wheat straw (UWS) as control2) fungal treated wheat straw before mushroom formation (FTWS)3) spent wheat straw (SPWS) after mushroom was harvested. Results indicated that the total tract digestibility of DM, OM, CP, CF, NDF, ADF, cellulose, as well as the TDN were significantly (P0.05) higher in FTWS than the UWS and SPWS. The digestibility of gross energy (GE) was also significantly (P0.05) increased in FTWS than the control straw and the spent wheat straw. Average daily consumption of DM, OM and digestible DM and digestible OM were significantly (P0.05) increased for FTWS in comparison to the UWS and SPWS. When DMI, OMI, DDMI and DOMI were expressed as g/kg BW 0.75 , significant (P0.05) differences were also observed. In all cases, intake of FTWS was the highest and SPWS was the lowest, however no significant differences were observed between the UWS and SPWS. In comparison to the UWS, both species of fungi increased the digestibility of DM and OM as well as the voluntary intake, at the stage of mycellial running however, FTWS with species of F-77 had significantly (P0.05) the highest nutritive value. When the fermentation period prolonged up to the time of mushroom harvesting, the digestibility and intake of SPWS were significantly (P0.05) decreased for both species of fungi. In conclusion, inoculation of wheat straw by two species of pleurotus fungi, at the stage of FTWS improved the digestible organic mater intake as a nutritive value index, but at the stage of SPWS, the nutritive value was lower than that of the initial wheat straw.