Varroa Jacobsoni (oud.) in honeybee colony
2000
Gregorc, A. (Ljubljana Univ. (Slovenia). Veterinary Fac.)
Parasite Varroa jocobsoni was found on indian bee Apis cerana and determined in the beginning of 20 century. Today the parasite is present worldwide. In developing stages and on adult honeybees V. jacobsoni destroys host tissue, sucks haemolymph, causes abnormal bee body development, excretes roxins and transmits causative agent of secondary diseases. Developing and mating take place in bee brood under the comb cell cap. Reproductive female mites prefer to enter in the drone brood than worker brood. Both, degree of V. jacobsoni development in the colony and colony survival depend on the number of newly developed and naturally mites in the colony. In infested colony the number of young bees is reduced, old bees are dying progressively, all bee casts suffered and scattered brood pattern appear with necrotically changed developing bee stages. The evaluation of the colony infestation level is diagnostically important. Diagnostics methods are, medical treatment, countingthe number of naturally mites, examinating and determinating the levelof old bees, worker and drone brood infestation, and finding deformed bees. V. jacobsoni parasitism has an influence on the beekeeping economy. V. jacobsoni control aims to reduce the mite number on a tolerant level in the colony. Timing and control methods are epizootiologically important and have to be geographically organised. Unproper and irregular use of acaricide has aninfluence on a development of mites resistance to acaricides. Applied research results and beekeeping practice could help to breed V. jacobsoni moretolerant honeybee strains.
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