Results of Doxycycline Administration on Bee Colonies

The aim of the study was to estimate the impact of antibiotic doxycycline on the spring development of the bee colonies, worker bees’ bodies chemical composition, development of hypopharyngeal glands and some physicochemical parameters of honey. The experiment was conducted during the spring stimulating feeding at apiary of Research Center of Stockbreeding and Agriculture, Smolyan, Bulgaria. Two groups of bee colonies were formed – control and experimental. The control group was fed with sugar solution (sugar/water 1:1) and experimental group with the addition of antibiotic doxycycline at a dose of 500 mg/L in sugar solution. Significantly lower values were obtained for the strength of the bee colonies and the amount of sealed worker bee brood fed with doxycycline than the control group. Strong correlations were found between the amount of sealed worker bee brood and the quantity of bee pollen and the quantity of honey and bee pollen in the both groups. From this study, it was concluded that development of hypopharyngeal glands was not positively affected after application of antibiotic doxycycline at a dose of 500 mg/L. Based on the results obtained there is no difference in physicochemical parameters of honey samples from the control and experimental group. In all cases testing for doxycycline residues in honey samples from the experimental group was relevant and high. Therefore, the authors do not recommend doxycycline in the beekeeping.