title: Bioavailability of organic and inorganic zinc sources in male broilers.
abstract: The objective of the current study was to determine the bioavailability of an organic zinc source (Availa-Zn) compared with zinc sulfate in a European-type broiler diet. A total of 480 one-day-old male Ross 308 broilers were housed in 48 digestibility cages (10 birds per cage), being randomly divided over 9 treatments. At d 3, the number of birds was standardized to 8. Birds were fed a basal wheat-maize-soya diet (containing 33.5 mg of Zn/kg) with different supplementation levels of zinc (reference zinc source: inorganic zinc sulfate: 0, 5, 10, 15, 20, and 40 mg of Zn/kg of feed; test zinc source: Availa-Zn: 0, 5, 10, 15 mg of Zn/kg of feed). Production performance and tibia zinc content were measured. There were no differences in production performance between the different zinc sources when fed to broilers until 21 d of age. Tibia zinc content was increased linearly with the dietary zinc content up to 20 mg/kg zinc sulfate. The relative biological value of organic zinc was 1.64 compared with zinc sulfate as a reference zinc source (1.00), as indicated by the slope ratio of the linear response curves for both zinc sources, using tibia zinc content as a response parameter. In a practical European broiler diet, the organic Availa-Zn had a higher bioavailability than inorganic zinc sulfate.
authors.affiliation: Schothorst Feed Research, PO Box 533, 8200 AM Lelystad, the Netherlands. lstar@schothorst.nl
authors.forename: L
authors.initials: L
authors.lastname: Star
authors.forename: J D
authors.initials: JD
authors.lastname: van der Klis
authors.forename: C
authors.initials: C
authors.lastname: Rapp
authors.forename: T L
authors.initials: TL
authors.lastname: Ward
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001682:Biological Availability; D001842:Bone and Bones / Q000737:chemistry; D002645:Chickens; D004032:Diet / Q000662:veterinary*; D004305:Dose-Response Relationship, Drug; D008297:Male; D015032:Zinc / Q000737:chemistry* / Q000493:pharmacokinetics*
chemical_list: D015032:Zinc