Dipartimento di Sanità Pubblica e Zootecnia, Università degli Studi di Bari, 70010, Bari, Valenzano, Italy.
Exp Appl Acarol. 2011 Jul;54(3):313-8. doi: 10.1007/s10493-011-9439-3. Epub 2011 Mar 24.
We investigated the effect of prolonged exposure to low temperature on engorged females of Rhipicephalus sanguineus. Five groups of two females (F1-F5) were maintained at 8 ± 2°C, 70 ± 10% RH, and 24 h scotophase, for 15, 30, 45, 60 and 75 days. One group was maintained in the incubator (26 ± 1°C, 70 ± 10% RH, and 24 h scotophase) as control. The results show that egg hatch rate, longevity and reproductive fitness of engorged females of R. sanguineus are negatively correlated with the duration of exposure to low temperature, whereas preoviposition period was positively correlated with exposure to the cold. This shows that the engorged female ticks are sensitive to prolonged exposure to low temperature, and it may explain why females of this tick species are not reproductively active during winter. Our results confirm that temperature is a major limiting factor for the establishment of stable R. sanguineus populations in cold temperate regions of Europe.
我们研究了长时间暴露在低温下对吸血雌蜱 Rhipicephalus sanguineus 的影响。将五组各两只雌蜱（F1-F5）分别维持在 8±2°C、70±10%RH 和 24 小时暗相，持续 15、30、45、60 和 75 天。一组在孵育器中（26±1°C、70±10%RH 和 24 小时暗相）作为对照。结果表明，R. sanguineus 吸血雌蜱的卵孵化率、寿命和生殖适应性与低温暴露时间呈负相关，而预产卵期与寒冷暴露呈正相关。这表明饱血雌蜱对长时间暴露在低温下非常敏感，这可能解释了为什么这种蜱类雌性在冬季不具有生殖活性。我们的研究结果证实，温度是欧洲寒冷温带地区 R. sanguineus 种群建立的主要限制因素。
