Nutritive Value Evaluation of Processed Chickpea (Cicer arietinum) Residues with some Chemicals Based on in vitro, in situ and X-Ray Diffraction (XRD) Techniques

This research was conducted to investigate the the effect of sodium hydroxide (NaOH, 50 g/kg DM), calcium oxide (CaO, 160 g/kg DM), hydrobromic acid (HBr, 60 mL/kg DM) and hydrogen peroxide (H2O2, 57 mL/kg DM) processings on the nutritive value of chickpea (Cicer arietinum) residues. The chemical composition of the samples was determined using the standard methods. Degradability trial was done using nylon bag technique. In vitro digestibility of the samples was determined by the batch culture procedure. X-ray diffraction method (XRD) was used to determine the crystallininty degree of the samples. Treatments of NaOH, CaO and H2O2 increased the ash content (P 0.0001). The ether extract (EE) was reduced by the NaOH and H2O2 treatments (P=0.0006). Except CaO, the other treatments reduced (P 0.0001) the neutral detergent fiber (NDF). Processing with HBr increased (P=0.0014) total digestible nutrients (TDN), net energy for lactation (NEl), and net energy for gain (NEg). CaO, HBr, and H2O2 treatments increased the effective ruminal degradability (ERD) of dry matter at ruminal outflow rates of 0.02, 0.05 and 0.08 h-1 (P=0.0074, P 0.0001). Except CaO (P 0.0001), the other treatments had no positive effect on the samples in vitro digestibility. The treatments increased the efficiency of microbial biomass at the end of 24 h incubation (P 0.0001). Chemicals reduced the crystallinity degree of chickpea residues compared to the control. The least crystallinity percentage was observed in CaO treated samples. Totally, based on the in vitro and in situ results, treatments, especially HBr, had a positive effect on nutritional value of chickpea residues. However, these results must be confirmed or invalidated by in vivo tests.