Investigation on the Effects of Different Levels of Energy and Energy to Protein Ratios on the Performance of Fars Native Laying Hens During the Second Phase of Production

摘要

The effects of different levels of metabolizable energy and energy to protein ratios on the performance of Fars native laying hens were examined during the second laying phase. In a feeding trial, 216 Fars native hens 42 weeks old were randomly allotted to 9 experimental diets using 6 replicated groups of 4 birds per cage. The diets were formulated with 3 levels of ME (2700, 2900 and 3100 kcal/kg diet). At each level of energy, 3 energy to protein ratios (195, 215 and 239) were considered. The diets were fed ad libitum for a period of 20 weeks (42-62 weeks). The results indicated that there were no significant differences in egg production, egg weight, body weight gain and livability at the end of the experiment (65 week of age) (P>0.05). Daily feed intake was significantly lowered in hens fed the first (ME=3100 Kcal/kg, CP=15.87), second (ME=3100 Kcal/kg, CP=14.43), third ration (ME=3100 Kcal/kg, CP=12.99) and fifth (ME=2900k Kcal/kg, CP=13.5%) as compared with the seventh ration (ME=2700 Kcal/kg, CP=13.82). Feed intake and feed conversion ratios (FCR) significantly decreased as the dietary energy level increased (P Scientific Publications Commission - Health Ministry Scientific Publications Commission - Science Ministry Yektaweb Company Site Keywords ?????, Academic Journal, Scientific Article, ???? ????? ??, ???? ????? ??, ???? ????? ??, ???? ????? ??, ???? ????? ??, ???? ????? ??, ???? ?? Vote ? 2015 All Rights Reserved | JWSS - Isfahan University of Technology