The purpose of the work was to check whether the application of Fe-glycinate chelate in mixtures fed to poultry in an amount covering 50 or 25% of the requirement would decrease the physical, morphometric and strength parameters of tibia bones in male Ross-308 broiler chickens in comparison to groups receiving Fe in an amount covering 100% of the requirement in the form of glycinate chelate or sulphate. It was found that the results for chickens from groups receiving Fe chelate covering 50 or 25% of the requirement were generally not lower than in the sulphate group and were higher than in the group receiving Fe in the amount covering 100% of the requirement. The presented results indicate that the standard requirement for Fe (40 mg kg-1 feed) as recommended by producers of Ross chickens may be too high if glycinate chelate is the source of Fe. This can be connected with the higher bioavailability of Fe from organic compounds in comparison to inorganic compounds.
Keywords: Broiler chickens; Fe sulphate; Fe-glycinate chelate; Lovered level; Mineral composition; Tibia bone quality.