AMEn Content of Meat and Bone Meal in Different Levals Subtituion With Adult Leghorn Roosters

A corn based diet with 3200 kcal/kg metabolizable energy and 12 percent crude protein was formulated and substituted with 0، 7. 5 and 15 percent level of each six samples of meat and bone meal from a local animal rendering plant in order to evaluate their apparent metabolizable energy (AMEn). Each of thirteen experimental diets fed to 6 adult Leghorn roosters in completely randomized design. AMEn values of experimental diets determined with total excreta collection method. AMEn content of each six samples of meat and bone meals were calculated by difference method. Gross energy efficiency varied from 0. 580 to 0. 65 among meat and bone meal sample at two substitution level، 7. 5 and 15 percent، respectively، but were not significant. The correlation coefficient between gross energy efficiency and crude fat was 0. 82. AMEn values of six meat and bone meal samples varied from 2033 to 3275 kcal/kg in 7. 5 and 15 percent substitution levels، respectively، but were not significant. Ether extract was solely the best variable of predicting AMEn content of meat and bone meal but more accuracy estimation of AMEn was resulted by including ether extract and gross energy in the model. The equation was as AMEn = -282)± 326 (+ 77) ±13 (ether extract + 0. 357) ± 0. 09(gross energy، R2 =0. 98، P=0. 0029. Mean content of AMEn in meat and bone meal was 2865±275 kcal/kg. The results showed that the studied meat and bone meals were rich of available energy for poultry.