Latif A A, Punyua D K, Nokoe S, Capstick P B
International Centre of Insect Physiology and Ecology, Nairobi, Kenya.
J Med Entomol. 1991 Jan;28(1):114-21. doi: 10.1093/jmedent/28.1.114.
Monthly collections were made of all ticks from 25 mature East African Zebu cattle and 5 yearlings for 13 mo on Rusinga Island, Lake Victoria, Kenya, from September 1986 to September 1987. The most common species were Rhipicephalus appendiculatus Neumann and Amblyomma variegatum F.; Boophilus decoloratus Koch and Rhipicephalus evertsi evertsi Neumann also were present in fewer numbers. Cattle were ranked according to their degree of resistance to each of the four species and to each stage in the life cycle of the three-host ticks. Ranking according to infestations of females and nymphs of R. appendiculatus, nymphs and larvae of A. variegatum, or all three stages of these two species when compared with the total burden gave statistically significant correlations. Sampling difficulties prevented the ranking of cattle for infestations of larvae of R. appendiculatus, although the numbers on cattle were high. On the other hand, failure of attempts to rank the cattle on females of A. variegatum, B. decoloratus, or R. e. evertsi counts was attributed to the small differences between tick numbers on cattle. Highly resistant cattle showed little or no seasonal fluctuations in tick numbers for most of the period compared with animals of low resistance, which showed an up to sevenfold increase in the magnitude of the tick burden when the tick challenge was high. Cattle with low resistance were responsible for much of the tick multiplication in the field, whereas highly resistant animals tended to limit the populations. There were no distinct differences between the numbers of each tick species on yearlings and mature cattle.
1986年9月至1987年9月，在肯尼亚维多利亚湖鲁辛加岛，每月从25头成年东非瘤牛和5头一岁小牛身上采集所有蜱虫，持续了13个月。最常见的蜱种是具尾扇头蜱（Rhipicephalus appendiculatus Neumann）和变异革蜱（Amblyomma variegatum F.）；微小牛蜱（Boophilus decoloratus Koch）和埃氏扇头蜱指名亚种（Rhipicephalus evertsi evertsi Neumann）数量较少。根据牛对这四种蜱虫以及三宿主蜱虫生命周期各阶段的抗性程度进行排名。与总负担相比，根据具尾扇头蜱雌蜱和若蜱、变异革蜱若蜱和幼虫或这两个物种所有三个阶段的感染情况进行排名，具有统计学显著相关性。尽管牛身上具尾扇头蜱幼虫数量很多，但由于采样困难，无法对牛进行该阶段感染情况的排名。另一方面，无法根据变异革蜱、微小牛蜱或埃氏扇头蜱指名亚种雌蜱数量对牛进行排名，是因为牛身上蜱虫数量差异较小。与抗性低的动物相比，抗性高的牛在大部分时间里蜱虫数量很少或没有季节性波动，抗性低的动物在蜱虫侵袭高峰期蜱虫负担量增加多达七倍。抗性低的牛是田间蜱虫大量繁殖的主要原因，而抗性高的动物往往会限制蜱虫数量。一岁小牛和成年牛身上每种蜱虫的数量没有明显差异。
