title: Biological availability of phosphorus in defluorinated phosphates with different phosphorus solubilities in neutral ammonium citrate for chicks and pigs.
abstract: Two experiments were conducted to assess the bioavailability of P in five sources of defluorinated phosphate (DFP) that differed in P solubility in neutral ammonium citrate (NAC). In Exp. 1, 384 2-d-old male chicks were fed a corn-cornstarch-dextrose-soybean meal basal diet (1.22% lysine, 1.00% Ca, .45% P) or the basal with .05 or .10% P from monosodium phosphate (MSP), or .10% P from DFP with 60, 70, 75, 82, or 91% NAC soluble P. Each diet was fed to six pen replicates of eight chicks per pen for 14 d (58 to 402 g). Growth rate, feed/gain, and tibia breaking strength and ash concentration were improved (P < .001) by P supplementation, regardless of P source. Tibia strength and ash were regressed on P intake, and slope-ratios were calculated to assess the relative bioavailability of P in the DFP sources. The bioavailabilities of P in the 60, 70, 75, 82, and 91% NAC soluble DFP sources, relative to MSP (given a value of 100), were 81, 75, 84, 84, and 91%, respectively (linear, P < .08). In Exp. 2, 35 individually penned pigs were fed a corn-soybean meal basal diet (.95% lysine, .75% Ca, .33% P) or the basal with .15% P from MSP or from the five DFP sources. Each diet was fed to five pigs for 33 d (15.0 to 35.9 kg). Growth rate, feed/gain, and breaking strength of the metacarpals, metatarsals, and femurs were improved (P < .001) by MSP and DFP.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Animal Sciences, University of Kentucky, Lexington 40546.
authors.forename: R D
authors.initials: RD
authors.lastname: Coffey
authors.forename: K W
authors.initials: KW
authors.lastname: Mooney
authors.forename: G L
authors.initials: GL
authors.lastname: Cromwell
authors.forename: D K
authors.initials: DK
authors.lastname: Aaron
mesh_terms: D000821:Animal Feed; D000818:Animals; D001682:Biological Availability; D015519:Bone Density; D002645:Chickens / Q000378:metabolism*; D002951:Citrates / Q000737:chemistry*; D019343:Citric Acid; D005260:Female; D005269:Femur / Q000502:physiology; D005527:Food, Fortified; D008297:Male; D008663:Metacarpus / Q000502:physiology; D008682:Metatarsal Bones / Q000502:physiology; D010710:Phosphates / Q000737:chemistry / Q000493:pharmacokinetics*; D016226:Phosphorus, Dietary / Q000493:pharmacokinetics*; D011897:Random Allocation; D012044:Regression Analysis; D012995:Solubility; D013552:Swine / Q000378:metabolism*; D013977:Tibia / Q000502:physiology
chemical_list: D002951:Citrates; D010710:Phosphates; D016226:Phosphorus, Dietary; D019343:Citric Acid