Utilization of grape (Vitis vinifera), cranberry (Vaccinium macrocarpon), wild blueberry (Vaccinium angustifolium), and apple (Malus pumila/domestica) pomaces in broiler chickens when fed without or with multi-enzyme supplement

Abstract

Nutritive and functional values of fruit pomaces in poultry are unexplored. We determined apparent metabolizable energy (AME) and plasma metabolites in broiler chickens fed diets containing apple (APL), low-bush wild blueberry (LBP), cranberry (CRP), and grape (GRP) pomaces without or with multi-enzyme supplement (ENZ). A total of 360 one-day old Ross 708 male chicks were placed in 72 cages; 5 birds/cage were reared to day 13 and transitioned to either cornstarch–soy protein isolate basal diet or basal with 30% of either pomace without or with ENZ. Excreta samples were collected from day 17 to 20 and one bird/cage bled for plasma metabolites on day  21. Apple pomace showed a higher AME ( P = 0.008) than other pomaces; however, ENZ had no effect on AME. The AMEs were 3 250, 2 613, 2 394, and 3 008  kcal/kg DM for APL, LBP, CRP, and GRP, respectively. There was pomace and ENZ interaction on plasma alkaline phosphatase ( P = 0.04), and APL increased cholesterol levels ( P < 0.01). In conclusion, ENZ had no impact on energy increment in pomaces, but the AME values this study has established are nonetheless valuable for accurate poultry feed formulation. Plasma metabolites suggested pomace components are amenable to supplemental ENZ.