Varroatosis of bees of different breeding crosses of the Carpathian subspecies

Abstract

Goal. To study the features of the course of varroatosis invasion, the level of damage to the imago, broods of drone and working bees of various breeding formations of the Carpathian subspecies, to determine promising selection combinations according to the indicators of resistance against the disease in the Western region of Ukraine. Methods. The study was conducted during 2020 using general scientific methods: analytical (for analyzing the scientific literature, generalizing modern data on varroatosis, and justifying the direction of research), biometric (for mathematical processing of experimental data, assessing the variability of the studied features, and comparing selection groups), and statistical (to assess the probability of the difference between the studied features). Brood lesions were evaluated by analyzing the sealed brood of worker bees and drones. Biometric processing of the obtained results was carried out by methods of variational statistics using the Statistica 8.0 computer program. Results. Seasonal dynamics of development of varroatous invasion in bee colonies of all studied groups with minimum values at the beginning of the season and maximum — in the summer-autumn period was established. It was proved that the level of damage by the Varroa destructor mite depended significantly on the selection origin of bees. The least extensiveness of varroatous invasion of adults, broods of worker bees and drones was recorded in bee families of breeding cross ♀ micropopulation «67» ♂ micropopulation «915», which indicated their increased natural varroasticity. It was found that the drone brood was affected by mites much more intensively than the worker one, and this had an important epizootological significance. Conclusions. It was found that the level of varroatous invasion of bee colonies depended on the selection origin of bees. The highest natural varroasticity was found in bees of breeding cross ♀ micropopulation «67» ♂ micropopulation «915», which should be used in breeding work to increase the resistance of bee families to Varroa destructor. The obtained results confirm the prospects of the selection approach as a component of the integrated varroatosis control system.