RESULTS
Mean values of selected blood parameters according to sample timing are shown in Table 2. Using a MANOVA analysis, significant differences between first and second samples and between sexes were found, but there was no significant interactive effect between sample and sex (Table 3). Significant differences between the two samples were found in most of the parameters (Table 2). Among hematological parameters, all showed significant differences early and later in hacking, including red blood cells, lymphocytes and monocytes. Hemoglobin, PCV and thrombocytes decreased during captivity, but white blood cells and most related component metric values increased. All the biochemical parameters, apart from AST and LDH, showed significant differences (Table 2). Albumin and globulin increased as did cholesterol, calcium and potassium. Nitrogenous components, urea or uric acid, decreased together with glucose and sodium. Weights (body mass) of the nestlings varied significantly, being lower in the second sample. This decrease in body mass was similar for both sexes (Fig. 1).
For urea, the form of the distribution also changed from a skewed (quasi-Poisson) distribution in the sample when entering the hacking facility (Shapiro-Wills = 0.889, P < 0.001), to a normal distribution of values after their stay in the hacking facility (Shapiro-Wills = 0.965, P = 0.246, Fig. 2). A significant linear regression between standardized hatching date and urea level was found only for the first samples (r = 0.396, R2 = 0.16, P = 0.010), but not for the second samples, after their stay in captivity (r = 0.297, R2 = 0.08, P = 0.059) (Fig. 3).