TOTAL CHOLESTEROL AND CORTICOSTERONE CONCENTRATION RELATIONSHIP IN BLOOD PLASMA OF LAYING HENS

The aim of this study was to analyze the effect of laying hens housing condition on the plasma total cholesterol and corticosterone concentrations relationship at the beginning, middle and end of the laying period. The experiments were performed in ISA BROWN egg production pullets, kept in a poultry house for rearing with deep litter technology. Blood samples (2 ml) of all hens in experimental groups were collected from brachial vein at 22, 28, 35, 41, 47, 52, 58 and 66 weeks of age. Plasma corticosterone levels were analyzed by radioimmunoassay and plasma total cholesterol by spectrometry. One-way ANOVA showed significant differences in cholesterol as well as corticosterone levels of blood plasma of laying hens during the experimental period. A very low relationship was found between individual total plasma cholesterol and corticosterone concentrations during the monitored period.