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Effect of different levels of protein with or without zinc supplementation on New Zealand White rabbits performance
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Abstract: The effects of dietary protein level and type of zinc supplementation (organic and inorganic form) on productive performance, digestion coefficients, carcass traits, some blood components, immunological response efficiency and economical efficiency were evaluated on 102 New Zealand White male rabbits (5 weeks old) with average body weight of 669.0±4.4 g. Rabbits were divided into two homogeneous main groups (each included 51 animals). The 1st group was fed a formulated diet containing 16.34 % crude protein (CP) and the 2nd was fed on diet containing 14.46 % CP (low protein). Each main group was divided into three equal sub groups. The 1st sub group was fed basal diet without zinc (Zn) supplementation, the 2nd and the 3rd sub groups were fed the same basal diet supplemented with 100 mg Zn/kg diet as zinc sulfate (ZnSO4, inorganic form) and zinc methionine (Zn-Met, organic form), respectively, to obtain final 6 experimental groups. Results showed that reduction of the protein content in the diet significantly (P<0.01 or 0.05) reduced LBW, DWG, FI, FC, PI and live rabbits percentage, values of digestibility coefficients of DM, OM, CP, CF and EE, nutritive values as DCP and TDN and lower dressing percentage at 13 weeks of age. Feeding a low level of protein significantly (P<0.01 or 0.05) decreased serum total protein, albumin, globulin, albumin-globulin ratio, creatinine, urea, AP, thyroid hormone (T4 & T3) concentrations, WBC’s count (103 /mm3), lymphocyte, antibody titer against SRBC at different four weeks post immunization and lower economical efficiency value. Zinc addition to the rabbits diets improved significantly (P<0.01 or 0.05) LBW, DWG, PI and live rabbits percentage at different periods of the experiment, digestion coefficients and nutritive values and some carcass traits. Rabbits fed diet supplemented with ZnSO4 or Zn-Met showed significantly (P<0.01 or 0.05) higher serum Zn level, total protein, albumin, albumin-globulin ratio, creatinine, transaminase enzymes (AST and ALT), AP and thyroid hormones concentrations, WBC's count, lymphocyte percentage, antibody titer against SRBC compared with those fed diet without Zn supplementation. Rabbit fed diet supplemented with Zn-Met had significantly (P<0.05) heaviest LBW, DWG and higher WBC's count, lymphocyte percentage, antibody titers against SRBC especially at two and four weeks post immunization and heighten cellular immunity especially at nine and twelve hours post injection compared with ZnSO4 supplementation. Conclusively, it could be concluded that additions of Zn to diet containing low CP content reduced significantly the negative effects resulted from reducing protein content in the rabbit diets. Rabbit fed diet containing 14.46 % CP supplemented with Zn resumed good productive performance, improved nutrients digestion coefficients and nutritive values, carcass traits, immune response efficiency and economical efficiency nearly or slightly more than that received diet contained 16.34% CP with no Zn added at different periods.
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| Publication year |
2006
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| Pages |
188p.
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| Availability location |
مكتبة معهد بحوث الانتاج الحيوانى- شارع نادى الصيد- الدقى- الجيزة
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| Availability number |
967
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| Organization Name |
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| Country |
Egypt
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| Department |
Rabbit, Turkey and Water Fowl Research Department
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| Author(s) from ARC |
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| Agris Categories |
Animal feeding
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AGROVOC
TERMS |
Feed conversion efficiency.
Immunity.
Nutritive value.
Performance testing.
Proteins.
Rabbits.
Zinc.
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| Publication Type |
Master Thesis
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