title: Estimation of standardized phosphorus retention for inorganic phosphate sources in broilers.
abstract: Two experiments were conducted to estimate standardized P retention (SPR) values of dicalcium phosphate (DCP), monocalcium phosphate (MCP), and monopotassium phosphate (MKP) in broilers. In total, ninety-six 22-d-old male broilers with similar BW (780 g average) were used in each experiment. The chicks were randomly allotted to 1 of 4 treatments (P-free, DCP, MCP, or MKP diets) with 6 replicate cages of 4 chicks each in a completely randomized design. After 3-d acclimation, chicks were fasted for 24 h and then fed P-free, DCP, MCP, or MKP diets for 4 h in Exp. 1 or 72 h in Exp. 2. Excreta samples were collected for a total of 28 or 52 h (24 or 48 h after feed withdrawal) in Exp. 1 and 96 or 120 h (24 or 48 h after feed withdrawal) in Exp. 2, respectively. The excreta collection time of 52 h in Exp. 1 or 96 h in Exp. 2 was adequate for the estimation of SPR. The estimated basal endogenous P losses (EPL) in chicks fed the P-free diet were 109 ± 4 mg/52 h per bird and 49.2 ± 4.0 mg/96 h per bird in Exp. 1 and 2, respectively. The SPR values of inorganic phosphate sources corrected by the above basal EPL differed (P < 0.001) in Exp. 2 but not in Exp. 1. However, these SPR values were very similar between the 2 experiments with 68.7, 69.8, or 76.6% in Exp. 1 and 71.8, 70.6, or 78.3% in Exp. 2 for DCP, MCP, or MKP, respectively. The results from the current study indicated that, compared with the 72-h feeding and 96-h excreta collection procedure, the 4-h feeding and 52-h excreta collection procedure was a relatively quicker time- and labor-saving method for estimating the SPR values of inorganic P sources in broilers. The estimated SPR values of commonly used inorganic P sources (MCP and DCP) were about 70%.
authors.affiliation: Mineral Nutrition Research Division, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China.
authors.forename: S B
authors.initials: SB
authors.lastname: Liu
authors.forename: J J
authors.initials: JJ
authors.lastname: Xie
authors.forename: L
authors.initials: L
authors.lastname: Lu
authors.forename: S F
authors.initials: SF
authors.lastname: Li
authors.forename: L Y
authors.initials: LY
authors.lastname: Zhang
authors.forename: Y
authors.initials: Y
authors.lastname: Jiang
authors.forename: X G
authors.initials: XG
authors.lastname: Luo
mesh_terms: D000818:Animals; D002645:Chickens / Q000378:metabolism*; D008297:Male; D010710:Phosphates / Q000737:chemistry / Q000378:metabolism*; D016226:Phosphorus, Dietary / Q000008:administration & dosage / Q000032:analysis*
chemical_list: D010710:Phosphates; D016226:Phosphorus, Dietary