Growth Performance, Cecal Fermentation and Blood Biochemistry of Rabbits Fed Diet Supplemented with Urea - Bentonite Combination

Abstract

Seventy six New Zealand white rabbits of about 700 ± 80 gm live weight were used to evaluate the influence of diet supplemented with urea-bentonite combination on cecal characteristics, metablism and rabbit growth performance. The rabbits were assigned into four dietary treatments control, bentonite-supplemented (with 2.5% sodium bentonite), urea-supplemented (with 1% urea) and urea – bentonite co-supplemented (1% urea+ 2.5% sodium bentonite). Co-supplementation decreased cecal pH value and ammonia nitrogen (NH3-N) concentration, increased total volatile fatty acids (VFAs) concentration, increased butyrate at the expence of acetate and propionate, increased fermentation efficieny and bacterial mass. Additionally, co-supplementation increased serum total proteins and glucose concentrations while no change was recorded in serum urea and creainine concentrations. Serum levels of AST were decreased in all experimental groups in comparison with control group whereas, serum levels of ALT were increased only by addition of urea alone. Moreover, urea-bentonite combination achieved an improvement in live weight gain and feed conversion effeciency by about 32% and 33% respectively with reference to control and thus considered cost effective. The study indicates that, a low cost urea-bentonite combination can replace about 50% of protein content of the high cost conventional rabbit feed and additionally improve rabbit growth performance that would be a valuable feeding strategy in developing countries.