A Comparison of Morphometric Indices, Mineralization Level of Long Bones and Selected Blood Parameters in Hens of Three Breeds

The aim of the study was to compare morphometric indices and the mineralization level of humerus, femur and tibia in Leghorn (H-22), Sussex (S-66) and Rhode Island Red (R-11) hens at different age (weeks 6, 16, 45 and 64), as well as some blood parameters. The material for the experiment was one-day old chicks of breeds: Leghorn (H-22), Sussex (S-66) and Rhode Island Red – RIR (R-11), which were separated into three groups. At 6, 16, 45 and 64 weeks of the study, 10 birds selected from each group were weighed, slaughtered, and their right femurs, tibiae and humeri were dissected. After removing soft tissues, the bones were weighed and measured for length, diameter, and the Seedor index (SI) was calculated. The bones were analysed for the content of calcium (Ca), phosphorus (P) and crude ash (CA). At 64 weeks, blood was collected from the hens and analysed for the concentration of Ca, P, pyridinoline and deoxypyridinoline. The study showed that hen breed had an effect mostly on morphometric indices of the bones such as bone weight and diameter, and the Seedor index (SI), while the age of birds had an effect on the bone mineralization level up to 45 weeks of age. The bone mineralization did not decrease in the studied breeds of hens at the end of the laying period. It was also found that heavier birds (RIR) had greater diameter bones and a higher SI, but the content of ash and minerals in the bones of that breed was generally similar to the Leghorn and Sussex hens. RIR hens exhibited higher plasma phosphorus concentration compared to Sussex hens. This may suggest that RIR birds have a slightly stronger bone system compared to Leghorn and Sussex hens.