Buczek Alicja, Bartosik Katarzyna, Buczek Alicja Magdalena, Buczek Weronika, Stanko Michał
Chair and Department of Biology and Parasitology, Medical University, Lublin, Poland.
Institute of Parasitology, Slovak Academy of Sciences, Slovak Republic.
Ann Agric Environ Med. 2019 Dec 19;26(4):548-554. doi: 10.26444/aaem/110128. Epub 2019 Aug 6.
This study presents for the first time a case of Hyalomma excavatum hyperparasitism and an analysis of this phenomenon in terms of its potential role in the biology of ticks and epidemiology of tick-borne diseases.
Two partially engorged H. excavatum females, one fully engorged female, and 5 males were collected from a naïve rabbit and placed together in a rearing chamber at a temperature of 25°C and 75% humidity.
3-4 days after tick detachment from the host's skin, one partially engorged H. excavatum female was observed attached to the idiosoma of the fully engorged conspecific female.
This study and observations of other authors confirm that partially engorged ixodid ticks can re-infest the host, and even co-feeding fully engorged ticks in order to collect the blood meal that is indispensable for important physiological processes. However, inefficient feeding of a partially engorged female on another conspecific female may reduce its reproductive performance and disturb the development of eggs and larvae. It seems that parasitism of a tick on another conspecific specimen, when at least one of them is infected by a microorganism, may be a yet poorly explored route of transmission of pathogens or symbionts between the ticks. Initiation of feeding by a hungry or partially engorged tick on a fully engorged specimen is an attempt to obtain food in the drastic conditions of the absence of a target host. Tick hyperparasitism with concurrent pathogen transmission can contribute to the genospecific diversity of pathogens in vectors and hosts.
本研究首次报道了一例穴形璃眼蜱过度寄生的病例，并从其在蜱生物学和蜱传疾病流行病学中的潜在作用方面对这一现象进行了分析。
从一只未接触过蜱的兔子身上采集了两只部分饱血的穴形璃眼蜱雌蜱、一只完全饱血的雌蜱和5只雄蜱，并将它们一起放置在温度为25°C、湿度为75%的饲养箱中。
蜱从宿主皮肤上脱落3 - 4天后，观察到一只部分饱血的穴形璃眼蜱雌蜱附着在一只完全饱血的同种雌蜱的体躯上。
本研究以及其他作者的观察结果证实，部分饱血的硬蜱可以再次寄生宿主，甚至会在完全饱血的蜱共同取食时获取对重要生理过程不可或缺的血餐。然而，部分饱血的雌蜱在另一只同种雌蜱上取食效率低下可能会降低其繁殖性能，并干扰卵和幼虫的发育。当至少其中一只蜱被微生物感染时，蜱在另一只同种标本上的寄生似乎可能是病原体或共生体在蜱之间传播的一条尚未充分探索的途径。饥饿或部分饱血的蜱在完全饱血的标本上开始取食是在没有目标宿主的极端条件下获取食物的一种尝试。蜱的过度寄生与病原体的同时传播可能会导致病原体在媒介和宿主中的基因特异性多样性。
