Ochanda H, Young A S, Medley G F
Department of Zoology, University of Nairobi, P.O. Box 30197, 00100 Nairobi, Kenya.
Parasitology. 2003 Jun;126(Pt 6):571-6.
Groups of nymphal Rhipicephalus appendiculatus Muguga, having a mean of 1 or 9 Theileria parva Muguga-infected salivary gland acini per tick, were kept under quasi-natural conditions at an altitude of 1950 m or 20 degrees C at a relative humidity of 85% in the laboratory and their survival and infection prevalence and abundance determined over time. Theileria parva infections for both categories of ticks survived in the nymphal ticks for 50 or 26 weeks post salivary gland infection under quasi-natural or laboratory conditions respectively. There was a distinct decline in infections in the more heavily infected nymphae under both conditions of exposure, reflecting an apparent density dependence in parasite survival. Nymphal ticks having an average infection level of 1 infected salivary gland acinus per tick, survived for up to 69 or 65 weeks post-repletion under quasi-natural or the laboratory conditions respectively. Nymphae having an average infection level of 9 infected salivary gland acini per tick survived for a similar duration under each of the 2 conditions. The infection level of 9 infected salivary gland acini per tick did not seem to significantly affect the survival of the tick vector compared to those having an average of 1 infected salivary gland acinus per tick.
将平均每只蜱有1个或9个感染了微小泰勒虫穆古加株的唾液腺腺泡的微小扇头蜱若虫组，置于海拔1950米或20摄氏度、相对湿度85%的实验室准自然条件下，测定其随时间的存活情况、感染率和感染丰度。在准自然或实验室条件下，这两类蜱的微小泰勒虫感染在唾液腺感染后的若虫中分别存活50周或26周。在两种暴露条件下，感染程度较重的若虫中的感染明显下降，这反映出寄生虫存活存在明显的密度依赖性。平均每只蜱有1个感染唾液腺腺泡的若虫，在准自然或实验室条件下，饱血后分别存活长达69周或65周。平均每只蜱有9个感染唾液腺腺泡的若虫在两种条件下的存活时间相似。与平均每只蜱有1个感染唾液腺腺泡的若虫相比，平均每只蜱有9个感染唾液腺腺泡的感染水平似乎并未显著影响蜱传播媒介的存活。
