title: Lysine requirements of pre-lay broiler breeder pullets: determination by indicator amino acid oxidation.
abstract: The indicator amino acid oxidation (IAAO) method allows the determination of amino acid requirements under conditions of low growth rate as found in pre-laying broiler breeder pullets. Cobb 500 breeder pullets (20 wk old; 2290 +/- 280 g, n = 4) were adapted (6 d) to a pelleted, purified control diet containing all nutrients at >or=110% of NRC recommendations. After recovery from surgery for implantation of a jugular catheter, each bird was fed, in random order, test diets containing one of nine levels of lysine (0.48, 0.96, 1.92, 2.88, 3.84, 4.80, 7.68, 9.60 and 14.40 g/kg of diet). Indicator oxidation was determined during 4-h primed (74 kBq/kg body), constant infusions (44 kBq x h(-1). kg body(-1)) of L-[1-(14)C]phenylalanine. Using the breakpoint of a one-slope broken-line model, the lysine requirement was determined to be 4.88 +/- 0.96 g/kg of diet or 366 +/- 72 mg x hen(-1) x d(-1) with an upper 95% CI of 6.40 g/kg of diet or 480 mg x hen(-1) x d(-1). IAAO allows determination of individual bird amino acid requirements for specific ages and types of birds over short periods of time and enables more accurate broiler breeder pullet diet formulation.
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada T6G 2P5.
authors.forename: Russell A
authors.initials: RA
authors.lastname: Coleman
authors.forename: Robert F
authors.initials: RF
authors.lastname: Bertolo
authors.forename: Soenke
authors.initials: S
authors.lastname: Moehn
authors.forename: Michael A
authors.initials: MA
authors.lastname: Leslie
authors.forename: Ronald O
authors.initials: RO
authors.lastname: Ball
authors.forename: Doug R
authors.initials: DR
authors.lastname: Korver
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D002250:Carbon Radioisotopes; D002645:Chickens / Q000502:physiology*; D008239:Lysine / Q000008:administration & dosage*; D009751:Nutritional Requirements; D010058:Oviposition / Q000502:physiology*; D010084:Oxidation-Reduction; D010649:Phenylalanine / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D002250:Carbon Radioisotopes; D010649:Phenylalanine; D008239:Lysine