Caging the queen with and without a comb section to achieve high efficacy of Varroa destructor control

Abstract

We investigated the application of queen caging to prevent autumn brood rearing. In comparative experiments, cages equipped with queen excluders on both sides were used. Only cages of the experimental group were supplied with comb sections. Survival of queens and the influence of various factors on brood rearing in cages and in the nest after the queen had been released were compared. The factors included the position of caged queens in the nest (in the middle or in the periphery), comb sections with empty or honey-filled cells, or with drone cells. The queens did not perish in cages supplied with a worker comb section, but 8% of them perished in cages without it. One queen perished in the cage with drone comb section. The number of colonies rearing brood and the brood area in the nest was higher than those in the cage. There was no correlation between the position of the caged queen in the nest and brood production in the cage and later in the nest. Comb section fullness had no impact on brood rearing in the cage. In cages with a drone comb section, no brood was observed besides eggs, but the total brood area (including eggs) did not differ from the worker comb section group in cages and later in the nest. Caging of the queens on an empty worker comb section for 21 days supports their survival and enables the beekeeper to carry out successful Varroa control earlier in autumn.