Chemical and fermentative characteristics of agricultural byproducts and their mixtures with roughages incubated with rumen fluid from slaughtered dromedaries

Within a pursuit of novel strategies aimed to raise animal production while expolting agricultural residues, using the dromedary camel rumen fluid degradation capabilities combined with a gas production (GP) technique approach, we investigated the in vitro kinetic parameters and some physical and chemical characteristics of three agro-industrial byproducts (AIBP) and their mixtures with three roughages. Chemical composition, buffering capacity, apparent degradability, pH and in vitro GP kinetic parameters were evaluated for citrus pulp, tomato peels, apple pomace, their mixtures (50:50 % DM basis) with milk thistle, crown daisy and a polyphyte hay. GP of AIBP ranged from 200 to 240 ml/g DM. Roughages produced significantly less gas whereas mixtures gave intermediate amounts of gas. Gas from AIBP evolved with significantly (P<0.05) shorter lag time (0.33 h) compared with roughages and mixtures. Mixing roughages with AIBP increased significantly (P<0.05) the initial and final pH. The buffering capacity significantly increased with some mixtures and decreased with some others. In conclusion, ruminal fluid from slaughtered dromedaries, like the conventional bovine inoculum, fermented the major plant polymers and can be used in in vitro degradability trials. Rapidly fermentable AIPB mixed with roughages can improve some nutritional aspects, providing dietary fibre and correcting some in vitro kinetic parameters.