The Mineral Profile of the Keel Bone of Laying Hens in Alternative and Cage Housing Systems


  • Ján Petrovič Slovak University of Agriculture in Nitra, Slovak Republic
  • Martin Mellen Slovak University of Agriculture in Nitra, Slovak Republic


laying hens, breeding system, calcium, phosphorus, keel bone


The aim of the study was to compare the keel bone profile of hens reared in cage and cage-free rearing systems. Experiments were carried out on a poultry farm on two alternative rearing systems and on one cage hall and measurements were carried out in laboratory conditions with Bovans Brown laying hens aged 32 to 47 weeks. The obtained results were evaluated using the statistical program SAS with version 8.2. In the set of 18 keel bone samples that we monitored, the average phosphorus content was measured as 15.19 with a variation of the measured values of 6.09, an average magnesium content of 0.49 with a variation of the measured values of 0.15, an average content of calcium 33.76 with a variation of the measured values of 14.78 and an average value of the ratio between calcium and phosphorus of 2.19 with a variation of the measured values of 0.09. Individual laying hen breeding systems did not have a statistically significant effect (P >0.05) on the content of phosphorus, magnesium, calcium and the ratio between calcium and phosphorus in the keel bone of laying hens.



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