Statistical Models for Assessing the Influence of Hygienic Behaviour of Worker Bees on the Level of Lysozyme and Total Protein Content in Their Hаemolymph

The hygienic behaviour of 26 bee colonies of apiaries in different regions of Bulgaria was tested. The degree of expression of hygienic behaviour was evaluated by the pinkilling method. A test field of square 5 x 5 cm was stuck onto a section of a honeycomb with a sealed worker brood. The bee colonies are divided into two groups: hygienic (cleaned over 95% of cells in the testing area on the 48^th hour) and nonhygienic (cleaned less than 95% of the cells in the testing area on the 48^th hour). Haemolymph has been taken from bees from each bee colony at 48^th hour and lysozyme levels and total protein content has been defined. Multivariate analysis (ANOVA) was used to determine significant differences between hygienic and nonhygienic colonies. The results obtained show significant differences between both groups (p 0.05) according to percent cleaned cells after killing the brood at 3^rd, 24^th and 48^th hours and insignificant differences between hygienic and nonhygienic colonies (p 0.05) for both parameters-lysozyme and total protein. Bivariate correlation was applied to investigate the impact of hygienic behaviour on lysozyme levels and total protein content. Low negative correlation (r=0.33) between total protein and hygienic behaviour was established which means that an increase of the activities related to the cleansing of honeycomb cells leads to a decrease in the total protein content. Low correlation (r=0.35) between hygienic behaviour and lysozyme levels was found i.e. higher levels of lysozyme are reported with more pronounced hygiene behaviour. The calculated regression model for lysozyme (P=0.24826) is statistically insignificant but the regression model for total protein is statistically significant (P=0.003153) and can be used to predict the relation between total protein content in the haemolymph and hygienic behaviour of bee colonies.