بررسی ارزش غذایی و عملکرد علف سبز غلات تولید شده در سامانه هیدروپونیک

     This study was conducted to assess the nutritive value and performance of green fodder (GF) production in hydroponic system. A mixture of barley (100 kg) and corn (80 kg) seeds was prepared and grown in an automatic controlling growing chamber that contained 7 shelevs, each with 16 special trays capacity. From each shelf, 6 trays were taken out after 7, 8, 9 and 10 days (as treatment) and fresh weight was recorded and sampled. Chemical composition and in vitro digestibility was determined. The performance and cost of GF production were estimated. Results showed that the fresh GF yield was 5.25 times of the original seed nevertheless, dry matter obtained was 23.8% less than the initial spent seed. Crude protein (CP) content of GF was significantly higher than that of barley (P=0.0076) and corn grain (P=0.0071) but such elevation in CP was mainly related to non-protein nitrogen. Organic matter digestibility of GF reduced as compared to the barley (P=0.0079) and corn grain (P=0.0087) and ME content. No differences were obtained among the GF treatments for nutrient contents and digestibility.The estimated cost per kg DM, CP, TP and ME obtained from GF were respectively 3.12, 2.01, 3.12 and 3.11 times of barley and corn grains. Ovreall, not only there is a negative balance of nutrients during converting barley and corn grains to green fodder in hydroponic system, but also the price of nutrients obtained by GF is several times higher than the original grains.