الفهرس 
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Abstract
The present work was carried out to evaluate the effects of protein and energy levels in the diets of early weaned rabbits on the growth performance and general health (healthiness of internal organs, liver and kidney). Three main groups of growing New Zealand White (NZW) rabbits (18 rabbit each ) weaned either at 26, 30 and 35 days old were subdivided into 9 groups, each of 6 with equal numbers of male and female rabbits. Three diets were formulated, from local feeds, to contain three levels of crude protein (16 &18 and 19.2 %) with three levels of energy (2522, 2831 and 3008 kcal DE / Kg diet). Each subgroup of rabbits was assigned randomly to one of the three formulated diets from time of weaning till end of the experiment. Body weight of the rabbits and consumed diets were weekly recorded and the feed conversion ratio was calculated. Blood samples were collected from the ear vein of the rabbits at end of experiment to separate sera for analyzing the total protein, albumin, cholesterol and total lipid. At end of experiment, 3 rabbits from each group were collected and slaughtered to evaluate the carcass quality data samples were collected from liver and kidneys for histopathological examination. The results of the study revealed that the growing rabbits weaned early at 26 days and fed 18% CP-diet had statistically higher live body weight than those fed the 19.2% CP-diet starting from the age of 63 days old till the end of the experiment at 84 days. Early weaned rabbits (at 26 days) may need to fed diet containing 18% CP for nearly 24 days following early weaning (26 days) and the excess of protein in the diet would be not beneficial in achieving more body weight development or weight gain. The results also showed that there were no statistical differences concerning body weight and weight gain in the mid weaned rabbit groups fed 18% or 19.2% CP-diets along the experimental period (30-77 days of age). Body weight gain in the mid weaned rabbits (30 d) was not increased due to feeding 18 & 19.2% CP-diets during the growing period from 42 to 84 days old than those fed the 16% CP diet. Increasing the dietary protein level to 18% instead of 16% in mid-weaned rabbits could be advisable only during the first 2 weeks after weaning. In the late weaned rabbits (35 days), feeding the high protein-high energy diets (18% and 19.2% CP and 2831 & 3008 kcal DE/ kg) did not improved body weight or body weight gain along the experimental period (35- 84 days). Feed intake is statistically the lowest ( 5750, 5340 and 4900 g) in the rabbit groups weaned at 26, 30 and 35 days respectively and fed the high protein-high energy diets (19.2 % CP and 3008 kcal DE/ kg). Feed conversion ratios (FCR) were mostly better and significantly less in the rabbit groups weaned early (26 or 30 days) and fed the high protein-high energy diets compared to the rabbit groups fed the recommended levels of CP& DE and weaned at 26 or 30 days of age. The data show that either of dietary protein and energy levels or age of weaning the kits had no significant impact on organs weight or percentage to live weight at slaughtering. Feeding the growing rabbit the high protein- high energy diets increased the fat percentage of dressed carcass. The liver of rabbit received high energy high protein diet showed swollen hepatocytes with clear and granular or vacuolated cytoplasm besides hypertrophy of Von Kupffer cells. Moreover, the kidney showed vacuolated renal tubular epithelium.