An experiment was conducted on 72 German Angora rabbits (42 youngs and 30 adults) divided into three groups to assess the effect of three experimental diets (T1, T2 and T3) with different levels of groundnut cake replaced by rice bran on their growth performance, wool yield, quality, and digestibility of nutrients. The inclusion rate of groundnut cake was decreased from 20 to 15 to 10% and that of rice bran increased from 13 to 18 to 23% in T1, T2 and T3, respectively. The same diets presented 16.1, 15.1 and 14.0% DM of crude protein and 11.3, 11.1 and 10.9 MJ/kg DM of digestible energy, respectively. All animals were kept under similar housing and management conditions and the experiment was continued for a period of 225 days (3 shearings). No significant effects of the experimental diets on body weight gain, wool yield and wool attributes were observed in young and adult rabbits. However, the wool yield at the 2nd shearing was higher in the T1 group (P<0.05) indicating the positive effect of a diet higher in protein and energy on the wool production at an early stage of growth. Voluntary intake both of concentrates and roughages were not affected by the dietary treatment. The digestibility coefficients of dry matter and crude fibre were increased both in young and adult rabbits with the reduction of groundnut cake, while those of crude protein and ether extract were decreased in young rabbits only. From this experiment it can be concluded that groundnut cake can be safely replaced with rice bran in adult feeds at rates of up to 10% of the total content, while in young rabbits it may not be advantageous to go above a 5% level of replacement to avoid a substantial reduction in protein concentration, and the impairment of growth and wool production.
angora rabbit; groundnut cake; rice bran; digestibility; growth; wool