Determination and prediction of the digestible and metabolizable energy values of poultry by-products for swine

Abstract

The experiment was carried out to determine the chemical and energetic composition of five poultry by-products and to develop prediction equations of digestible and metabolizable energy values based on the chemical and physical composition of feedstuffs. Twenty-four crossbred castrated male swine averaging 26.3  1.9kg of initial weight were allotted to a randomized block design, with six treatments, four replicates and one animal per experimental unit, to determine the digestible and metabolizable energy values. The treatments consisted of a basal diet and five poultry by-products, that replaced in 20% the basal diet. The crude protein content of poultry by-products ranged from 52.77 to 62.47% and the digestible and metabolizable energy values, from 3,281 to 4,567kcal/kg and 3,151 to 4,293kcal/kg, respectively. The prediction equations of digestible and metabolizable energy that showed higher R2 were: DE = 8226.97 – 33.01xCP -160.05xAsh and ME = 10146.5 – 166.27xAsh – 1259.25xCa.