Effect of Chemical and Biological Processing Methods on Chemical Composition, Gas Production Parameters and In Vitro Digestibility of Cicer Arietinum Wastes

This research was conducted in order to investigate the effect of chemical and biological processing on the chemical composition, gas production parameters and in vitro digestibility of Cicer arietinum wastes in a completely randomized design (7 treatments and 3 replicates). Treatments were: unprocessed Cicer arietinum wastes (control) and processed with water (2.5 liter/kg DM), sodium hydroxide (50 g/kg DM), hydrogen peroxide (114 ml/ kg DM), Aspergillus niger, Trichoderma harzianum and Pleurotus ostreatus fungi (5×105 spores/ml). The chemical composition of the samples was determined using the standard methods. Gas production test was used to estimate the parameters of gas production in samples. In vitro digestibility of the samples was determined by the batch culture method. Processing was effective on chemical composition of treatments (P<0.03). Except for water, the other treatments increased ash and decreased organic matter. Crude protein content was increased by different treatments. The highest amount was observed in Trichoderma harzianum (4.76 percent). Sodium hydroxide decreased neutral detergent fiber compared to control (54 percent versus 56.66 percent). Processing decreased gas production potential and rate. The lowest amount of these traits was observed in Trichoderma harzianum (162.9 ml/ 200 mg DM and 0.052 ml/ h respectively). Sodium hydroxide and Aspergillus niger treatments increased (P<0.01) dry matter and organic matter digestibility (58 and 62 percent for dry mater digestibility, 57 and 62 percent for organic matter digestibility respectively). Microbial mass production and its efficiency was increased by the treatments (P<0.0003). The highest increase was seen in Aspergillus niger treatment (160.28 mg/g DM and 0.48 respectively). Based on the results of this research, sodium hydroxide and Aspergillus niger treatments were effective in improving the nutritional value of Cicer arietinum wastes in laboratory conditions.