Efficacy of an evolved Escherichia coli phytase in diets of broiler chicks.
An evolved Escherichia coli-derived phytase was evaluated for its efficacy in improving growth performance and nutrient utilization of broiler chicks. One hundred forty-four 7-d-old male broiler chicks were grouped by weight into 6 blocks of 6 cages with 4 birds per cage. Six corn-soybean meal-based mash diets were randomly assigned to cages within each block. The 6 diets were adequate P (7.7 g of P/kg of diet), low P (3.9 g of P/kg of diet), low P diet plus 0.75 or 1.5 g of inorganic P from monosodium phosphate, and low P diet plus the evolved Escherichia coli phytase at 500 or 1,000 units/kg of diet. The chicks were fed the experimental diets from 8 to 22 d of age. The evolved Escherichia coli phytase improved weight gain (P < 0.05), feed intake (P < 0.01), percentage tibia ash (P < 0.01), and retention of P (P < 0.001), Ca (P < 0.01), N (P < 0.05), and a number of amino acids (P < 0.05). The evolved Escherichia coli phytase was, therefore, efficacious in improving broiler growth performance, bone characteristics, and retention of P, Ca, N, and a number of amino acids.
Onyango
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EM
Department of Animal Sciences, Purdue University, West Lafayette, Indiana 47907, USA.
Bedford
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MR
Adeola
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O
D010832:6-Phytase / Q000235:genetics / Q000494:pharmacology*; D000596:Amino Acids / Q000378:metabolism; D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001842:Bone and Bones / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002645:Chickens / Q000254:growth & development* / Q000378:metabolism; D004032:Diet / Q000662:veterinary*; D004926:Escherichia coli / Q000201:enzymology*; D019143:Evolution, Molecular; D009584:Nitrogen / Q000378:metabolism; D030781:Organisms, Genetically Modified; D010710:Phosphates / Q000737:chemistry / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D010843:Pichia / Q000235:genetics
D000596:Amino Acids; D010710:Phosphates; D010758:Phosphorus; D010832:6-Phytase; D009584:Nitrogen; C018279:sodium phosphate; D002118:Calcium