Influence of an Escherichia Coli-derived Phytase on Nutrient Utilization in Broiler Starters Fed Diets Containing Varying Concentrations of Phytic Acid.
From: Institute for Food, Nutrition and Human Health, Massey University, Palmerston North, New Zealand. V.Ravindran@massey.ac.nz
Poultry science
- Publish Date: Jan 2006
- ISSN: 0032-5791
- Volume: 85
- Issue: 1
- Pages: 82-9
- Medium: Print
- Language: English
- Citation (JAMA): Ravindran V, Morel P C H, Partridge G G, et al. Influence of an Escherichia Coli-derived Phytase on Nutrient Utilization in Broiler Starters Fed Diets Containing Varying Concentrations of Phytic Acid.. Poult. Sci. Jan 2006;85:82-9
Abstract
The influence of an Escherichia coli-derived phytase, on nutrient utilization was investigated in broilers fed starter diets containing different concentrations of phytate. The study was conducted as a 3 x 4 factorial arrangement of treatments with 3 concentrations of phytic acid (10.4, 11.8, and 13.6 g/kg; equivalent to 2.8, 3.3, and 3.8 g of phytate P/kg) and phytase (0, 500, 750, and 1,000 FTU/kg). One unit of phytase (FTU) is defined as the quantity of enzyme that releases 1 micromol of inorganic phosphorus/min from 0.00015 mol/L of sodium phytate at pH 5.5 at 37 degrees C. The dietary phytic acid concentrations were manipulated by the inclusion of rice bran. Increasing dietary concentrations of phytic acid resulted in reductions (P < 0.01) in AME. Phytase additions tended to increase AME (P = 0.07), regardless of dietary phytate concentrations. Apparent ileal digestibility coefficients of protein and most amino acids were influenced by phytate (P < 0.05 to 0.001) and phytase (P < 0.001). Phytase improved ileal protein and amino acid digestibility at all phytate concentrations, but the trend in responses to increasing phytase additions was different at different phytate concentrations as shown by significant phytate x phytase interactions (P < 0.01 to 0.001). At the lowest phytate concentration, the ileal digestibility coefficients increased with increasing phytase supplementation. At the medium and high phytate concentrations, the greatest responses were observed at 500 FTU/kg of phytase, with little improvement attributable to further additions. Ileal digestibility of P was lowered (P < 0.01) by increasing phytate concentrations and increased (P < 0.001) with increasing additions of phytase. A significant phytate x phytase interaction (P < 0.05) was also observed, where the improvements in P absorption with added phytase were found to be greater at high phytate concentrations. These data demonstrate the anti-nutritive effects of phytic acid and the potential of microbial phytase to improve energy utilization and the availability of P and amino acids in broilers fed starter diets.
Mesh Headings (Keywords): 6-Phytase, Amino Acids, Animal Feed, Animals, Chickens, Digestion, Dose-Response Relationship, Drug, Energy Metabolism, Escherichia coli, Ileum, Male, Phytic Acid
Check for Full Text / PubMed Unique Identifier (PMID): 16493949
This abstract is part of PubMed, a service of the U.S. National Library of Medicine. PubMed includes more than 17 million citations from MEDLINE and other life science journals for biomedical articles. See Copyright and Disclaimers.
Linked medical terms appearing on this page are added by Healia to help readers find more information and are not part of the original PubMed document.
The data herein was last updated on July 8th, 2008 and may not reflect the most current and accurate data available from NLM.