he present study aimed to determine the effects of using different level of prickly pear peels byproduct as an unconventional ingredient in the different of rabbits on productive performance, digestibility, some blood constituents, immune response, activity of certain digestive enzymes in pancreatic tissue and intestinal contents and economic of efficiency. Sixty weaned New Zealand White rabbits (NZW) male rabbits aged 35 days and weighed 600g ± 2.20 were equally and randomly divided into four groups (15 in each one). The experimental diets contained different levels of dried prickly pear peels (PPP) (0.0 control (C), 10, 20 and 30%), respectively. Results indicated that: The final live body weight, total weight gain and performance index were significantly (P<0.05) affected by PPP groups. The highest (P<0.05) values of live body weight, total weight gain and performance index were recorded by rabbits fed 30% PPP inclusion (2178g, 1577g and 74.59%) followed by received inclusion level of 20% PPP (2080g, 1482g and 66.45%), respectively compared with the 10% PPP (2000g, 1398g and 58.82%) or control (1990g, 1390g and 56.37%), respectively. Feed intake (g/ day), protein intake, and digestible energy intake were significantly (P≤0.05) decreased with increasing PPP levels. Rabbits fed PPP (30%) diet recorded a significant best FCR value followed by those of 20 and 10 % tested material, respectively. Digestibility coefficient and nutritive values (DM, CP, EE, CF, TDN, DCP and DE) were significantly improved for rabbits fed diet contained PPP compared to those fed the control diet. There were significant increases detected for plasma total protein, albumin and globulin while blood plasma of total lipids was significantly decreased by increasing PPP inclusion level compared to control groups. Liver function as AST and ALT activity were not affected by dietary treatments with supplementing PPP. Values of each of blood components including (red and white blood cells count) and hemoglobin were increased in rabbits fed diet contained PPP than those of the control, Also there is a significant increase in the activity of intestinal amylase, lipase and protease in rabbits compared to controls. Moreover the concentrations of IgG and IgM of rabbits were higher for rabbit supplemented with PPP than the control group. The best economical efficiency and relative economical efficiency values had been recorded with rabbits fed 30% PPP inclusion followed by rabbits received 20% and 10% treatment of PPP, respectively. It is concluded that supplemental dried prickly pear peels (PPP) at the rate of 30 or 20 % of the diet improved growth performance and health status of the NZW rabbits.
