Responses in digestibilities of macro-minerals, trace minerals and amino acids generated by exogenous phytase and xylanase in canola meal diets offered to broiler chickens

Atypical diets based on canola meal (584 g/kg) and dextrose, supplemented with phytase and xylanase individually and in combination, were offered to 120 male Ross 308 broiler chicks with six replicates for each of the four treatments. The objective was to determine the effects of phytase and xylanase on the apparent digestibility coefficients of macro-minerals, trace minerals and amino acids along the small intestine of broiler chickens. The combination increased phosphorus digestibility by a two-fold factor (0.694 versus 0.324), calcium digestibility by a three-fold factor (0.527 versus 0.178), increased zinc from -0.141 to 0.324 and increased sodium digestibility coefficients from -1.402 to -0.359 in comparison to the control diet. Similarly, phytase and xylanase in tandem generated better responses in the apparent ileal digestibility coefficients of amino acids. The enzyme combination significantly increased the digestibility of nine essential amino acids by from 5.47% (methionine) to 35.4% (threonine), and seven non-essential amino acids by from 13.9% (glutamic acid) to 32.9% (proline). The better responses in apparent ileal digestibilities of phosphorus, calcium, sodium, zinc and five other trace minerals in broiler chickens offered the combination diet was confounded by its higher enzyme recovery activities in comparison to the individual supplemented diets and the study may suggest that the inclusions of phytase and xylanase in tandem should be considered in diets containing canola meal for broiler chickens.