POTENTIAL OF IN VITRO α-AMYLASE AND PROTEASE ASSAYS IN EVALUATING BROILER DIETS SUPPLEMENTED WITH MULTI-ENZYME PRODUCT

Abstract

To determine the potential of in vitro duodenal α-amylase and protease assays in evaluating broiler diets with in-feed enzyme supplementation, a total of 320 straight-run day-old broiler chickens were divided into four groups and randomly assigned to one of four dietary treatments (T1 is with breedrecommended nutrient levels, T2 is with reduced nutrient levels, T3 is T1+multienzyme, and T4 is T2+multi-enzyme) having eight replications in a 2 x 2 factorial arrangement with nutrient levels and enzyme addition as main effects. At the end of each of three feeding phases, representative samples of birds were sacrificed for collection of duodenal digesta for the in vitro α-amylase and total protease activity assays. Growth parameters were also calculated. Generally, there were no significant effects of diet on growth performance parameters, and on the α-amylase and total protease activity in all feeding phases. This study suggests that in vitro duodenal α-amylase and protease activity assays can potentially be used to predict the effects of in-feed multienzyme on the growth performance and, thus, the quality of enzyme-supplemented broiler feeds.