HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Nyannor, E. K. D. Articles by Adeola, O. Search for Related Content PubMed PubMed Citation Articles by Nyannor, E. K. D. Articles by Adeola, O.

Corn Expressing an Escherichia Coli-Derived Phytase Gene: Comparative Evaluation Study in Broiler Chicks¹

Department of Animal Science, Purdue University, West Lafayette, IN 47907-2054

² Corresponding author: ladeola{at}purdue.edu

The efficacy of corn expressing an Escherichia coli-derived gene (corn-based phytase; CBP) and an E. coli-derived microbial phytase (expressed in Pichia pastoris) sprayed onto a wheat carrier (Quantum) was comparatively evaluated in two 14-d broiler chicken studies. In experiment 1, a total of 288 seven-day-old male broiler chicks were grouped by weight into 8 blocks of 6 cages, with 6 birds per cage, and used to measure growth performance, bone mineralization, and nutrient utilization. In experiment 2, a total of 192 seven-day-old male broiler chicks were used, with 4 birds per cage. Six dietary treatment groups were randomly allotted to the cages within each of 8 blocks. The corn-soybean meal-based diets used in each study consisted of a positive control adequate in P and Ca; a negative control (NC) low in P and Ca (no added inorganic P); the NC supplemented with 3,630, 36,300, or 363,000 phytase units (FTU) of CBP/kg; and the NC + 3,630 FTU of Quantum/kg. Growth performance and bone mineralization criteria were reevaluated in the second broiler study. Data from the 2 experiments were combined because there was no diet x experiment interaction and analyzed as a randomized complete block design. Weight gain decreased (P < 0.05) with a reduction in dietary P and Ca in the NC diet. Weight gain, feed efficiency, and percentage of tibia ash of birds fed 3,630 FTU/kg of either CBP or Quantum phytase were not different. There was a quadratic response (P < 0.01) to CBP supplementation of the NC diets in weight gain of the broiler chicks. Feed intake increased quadratically (P < 0.01) with CBP supplementation of the NC diets, but CBP supplementation of the NC diets did not affect feed efficiency. Tibia ash of birds fed the positive control diet was greater (P < 0.01) than that of birds fed the NC diet. There was a quadratic response (P < 0.01) to CBP supplementation of the NC diets in tibia ash of the broiler chicks. Birds fed supplemental phytase had greater (P < 0.01) ileal and total tract P and Ca digestibility than birds fed the NC diet. Data from the study suggest that E. coli phytase expressed in corn is efficacious in P-deficient broiler chick diets for the improvement of growth performance and indices of P utilization, which would minimize the need for supplemental P in broiler diets.

Key Words: broiler chick • corn phytase • digestibility • Escherichia coli-derived phytase • growth

¹ Journal paper No. 2007-18263 of the Purdue University Agricultural Research Programs.

This article has been cited by other articles:

				E. K. D. Nyannor, M. R. Bedford, and O. Adeola Corn expressing an Escherichia coli-derived phytase gene: Residual phytase activity and microstructure of digesta in broiler chicks Poult. Sci., July 1, 2009; 88(7): 1413 - 1420. [Abstract] [Full Text] [PDF]