Ritter W, Michel P, Schwendemann A, Bartoldi M
Tierhygienisches Institut, Freiburg.
Berl Munch Tierarztl Wochenschr. 1990 Apr 1;103(4):109-11.
The mite Varroa jacobsoni, an ectoparasite of the honey bee, was imported to Tunisia probably in 1976. Afterwards, this parasitosis caused severe losses of colonies for several years. The continued examination of the level of infestation in colonies of a "GTZ" project stated a steady number of mites since 1980. Only in a few colonies, the infestation was above the limit of damage. Though the colonies in North West Tunisia did not receive any treatment since 1986 there was no increase of infestation. In order to investigate the reason for this the mites' ability of reproduction was examined during two following years. The portion of infertile female mites in the worker brood in most of the colonies was with 50% considerably higher than in Europe. In Brazil, the adaptation between host and mite produced similar low reproduction rates. As, however, in Tunisia the portion of infertile females in the drone brood of the individual colonies corresponded to the one in the worker brood climatic conditions are supposed to be responsible.
雅氏瓦螨是蜜蜂的一种体外寄生虫，1976年可能被引入突尼斯。此后，这种寄生虫病在几年间导致蜂群大量损失。对一个“德国技术合作公司（GTZ）”项目蜂群的感染水平持续监测表明，自1980年以来螨的数量稳定。只有少数蜂群的感染程度超过了损害限度。尽管自1986年以来突尼斯西北部的蜂群未接受任何治疗，但感染情况并未增加。为了探究其中原因，在接下来的两年里对螨的繁殖能力进行了研究。大多数蜂群工蜂幼虫中不育雌螨的比例为50%，大大高于欧洲。在巴西，宿主与螨之间的适应性也产生了类似的低繁殖率。然而，在突尼斯，各个蜂群雄蜂幼虫中不育雌螨的比例与工蜂幼虫中的比例相当，因此推测气候条件是造成这种情况的原因。
