Copper-protein nutrition of New Zealand white rabbits under egyptian conditions

Abstract

One hundred and twenty male New Zealand White (NZW) rabbits of 35 days of age were randomly allotted to twelve groups. Rabbits of six groups were fed a low protein diet (16.44 % crude protein) and the other six were fed a high protein diet (18.5 % crude protein). Within each dietary protein level, three groups were supplemented with copper sulfate to supply either 0, 100 or 200 ppm copper/kg diet, while the other three were supplemented with copper chloride to supply the same levels of copper. Most of the studied traits were affected positively with the increase in each of protein and copper levels in the diets of NZW rabbits without interaction. The affected traits were : live body weight and daily gain ( Protein high vs low : 28.2 vs 23.4 g/d ; Cu 0-100-200 ppm : 22.1-25.9-29.2 g/d ; P<0.001), feed conversion, protein efficiency, nutrient digestibility and final margin, as well as, concentration of serum protem, albumin (Protein high : + 12 % vs low ; Cu 100 and 200 ppm : 8 % and 17 % vs O ppm ; P<0.001), urea, creatinine (P<0.01) and SGOT (P<0.05). Feed cost, serum globulin level, SGPi and sorne carcass and non-carcass components were insignificantly affected by levels of either protein or copper. Dressing percentage increased slightly with the increase of dietary protein and copper levels, while empty gut percentage (relatively to live body weight) decreased wIth addition of copper in rabbit diets. The effects of copper source and the interaction between protein level and each of copper level and source on the traits studied, did not show any significance.