Varroa sensitive hygiene

About: Varroa sensitive hygiene is a research topic. Over the lifetime, 714 publications have been published within this topic receiving 24928 citations. The topic is also known as: VSH.

Communal use of integumental wounds in honey bee (Apis mellifera) pupae multiply infested by the ectoparasitic mite Varroa destructor.

Abstract: The ectoparasitic bee mite, Varroa destructor, is highly adapted to its natural and adopted honey bee hosts, Apis cerana and Apis mellifera. Adult females perforate the integument of bee pupae in such a way that they and their progeny can feed. We examined the wounds that founder females made, and usually found one, and rarely up to three, integumental wounds on pupae of A. mellifera multiply infested by V. destructor. The punctures were mainly on the 2nd abdominal ster- nite of the host. These perforations are used repeatedly as feeding sites by these hemolymph-sucking mites and by their progeny. The diameter of the wounds increased during pupal development. In brood cells con- taining 4-5 invading female mites and their progeny, healing of the wound is delayed, normally occurring just before the imaginal moult of the bee pupa. These wounds are subject to microbial infections, and they are relevant to the evolution of behavioral traits in these parasitic mites and their relations to host bees.

The development of HopGuard® as a winter treatment against Varroa destructor in colonies of Apis mellifera

Abstract: The development of new veterinary medicinal products to control Varroa destructor is very important for the successful management of honey bee colonies. We tested natural plant compounds (hop acids) as active ingredients for a new veterinary drug for Varroa control. Tolerability of bees and efficacy against mites was tested in the laboratory and in the field. In laboratory tests, hop beta acids were proven to be safe for bees (5 % mortality) and effective against mites (93.3 % mortality); there is a six-fold safety margin for bees after individual dermal application compared to the lowest dosage highly toxic to mites. In a clinical study, these results were confirmed: bee colonies tolerated the treatment (<10 % mortality), while most of the mites were killed (efficacy up to 88 %). The treatment did not affect the adult bee population and winter survival of colonies.

Influence of resistant honey bee hosts on the life history of the parasite Acarapis woodi

Abstract: Non-infested, young adult honey bees (Apis mellifera L.) of two stocks were exposed to tracheal mites (Acarapis woodi (Rennie)) in infested colonies to determine how divergent levels of susceptibility in host bees differentially affect components of the mite life history. Test bees were retrieved after exposure and dissected to determine whether resistance is founded on the reduced success of gravid female (foundress) mites to enter the host tracheae, on the suppressed reproduction by foundress mites once established in host tracheae or on both. Cohorts of 30–60 bees from each of ten resistant colonies and eight susceptible colonies were tested in eight trials (three to five colonies per stock per trial) having exposure durations of 4, 9 or 21 days. The principal results were that lower percentages of resistant bees than of susceptible bees routinely became infested by foundress mites, individual infested susceptible bees often had more foundress mites than individual infested resistant bees did and mite fecundity was similar in both host types. The infestation percentage results corresponded well with similar results from a prior field test of these stocks and, thus, suggest that the bioassay is useful for assessing honey bee resistance to A. woodi.