determination of apparent and true digestibility of poultry by product meal in broiler chickens

in order to determination of ileum apparent and true digestibility of two samples of poultry by product meal, an experiment was conducted with a total of 60 day-old broiler chicks, ross 308 strain. poultry by-product meal was prepared from two slaughter house in alborz province. samples were sent to laboratory for determination of chemical analysis. the birds received commercial broiler starter and grower diets from day l to 30. on day 30, sixty birds of uniform nearly some body weight (38±4 g) were allocated to twelve groups of five birds each and assigned to twelve cages. there were three dietary treatments, two diets containing two samples of poultry by-product meal (pbpm) and a nitrogen-free diet. apparent digestibility values of the assay diet, using ileal contents, were calculated using chromic oxide as indigestible marker. true digestibility values were calculated using endogenous output determined by feeding a nitrogen-free diet. in day 42, birds were slaughtered by co2 and ileum content was collected. apparent and true digestibility of protein, ca, p and metabolizable energy were calculated. result showed there is difference between two samples of pbpm in chemical composition and nutrient digestibility. apparent metabolizable energy (ame) and apparent metabolizable energy corrected for nitrogen (amen) in sample 2 were higher than sample 1 (3665±137.75 vs. 3241±2.85 and 3495±134.45 vs. 3111±1.50, respectively) however these differences were not significant in some cases.