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

Abstract

In pursuit of novel strategies aimed to promote animal production while exploiting agricultural residues, using the dromedarycamel rumen fluid degradation capabilities combined with a gas production (GP) technique approach, we investigated the in vitrokinetic parameters and some physical and chemical characteristics of three agro-industrial byproducts (AIBP) and their mixtureswith three roughages. Chemical composition, buffering capacity, apparent degradability, pH, and in vitro GP kinetic parameters wereevaluated for citrus pulp, tomato peels, apple pomace, their mixtures (50:50 % DM basis) with milk thistle, crown daisy, and polyphytehay. GP of AIBP ranged from 200 to 240 mL/g DM. Roughages produced significantly less gas whereas mixtures gave intermediateamounts 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 significantly (P < 0.05) increased the initial and final pH. The buffering capacity significantly increasedwith some mixtures and decreased with some others. In conclusion, ruminal fluid from slaughtered dromedaries, like the conventionalbovine inoculum, fermented the major plant polymers and can be used in in vitro degradability trials. Rapidly fermentable AIPB mixedwith roughages can improve some nutritional aspects, providing dietary fiber and correcting some in vitro kinetic parameters.