Dudek Krzysztof, Skórka Piotr, Sajkowska Zofia Anna, Ekner-Grzyb Anna, Dudek Monika, Tryjanowski Piotr
Department of Zoology, Institute of Zoology, Poznan University of Life Sciences, Wojska Polskiego 71 C, 60-625 Poznań, Poland.
Institute of Nature Conservation, Polish Academy of Sciences, Mickiewicza 33, 31-120 Kraków, Poland.
Ticks Tick Borne Dis. 2016 Feb;7(1):172-179. doi: 10.1016/j.ttbdis.2015.10.014. Epub 2015 Oct 19.
The success of ectoparasites depends primarily on the site of attachment and body condition of their hosts. Ticks usually tend to aggregate on vertebrate hosts in specific areas, but the distribution pattern may depend on host body size and condition, sex, life stage or skin morphology. Here, we studied the distribution of ticks on lizards and tested the following hypothesis: occurrence or high abundance of ticks is confined with body parts with smaller scales and larger interscalar length because such sites should provide ticks with superior attachment conditions. This study was performed in field conditions in central Poland in 2008-2011. In total, 500 lizards (Lacerta agilis) were caught and 839 ticks (Ixodes ricinus, larvae and nymphs) were collected from them. Using generalised linear mixed models, we found that the ticks were most abundant on forelimbs and their axillae, with 90% of ticks attached there. This part of the lizard body and the region behind the hindlimb were covered by the smallest scales with relatively wide gaps between them. This does not fully support our hypothesis that ticks prefer locations with easy access to skin between scales, because it does not explain why so few ticks were in the hindlimb area. We found that the abundance of ticks was positively correlated with lizard body size index (snout-vent length). Tick abundance was also higher in male and mature lizards than in female and young individuals. Autotomy had no effect on tick abundance. We found no correlation between tick size and lizard morphology, sex, autotomy and body size index. The probability of occurrence of dead ticks was positively linked with the total number of ticks on the lizard but there was no relationship between dead tick presence and lizard size, sex or age. Thus lizard body size and sex are the major factors affecting the abundance of ticks, and these parasites are distributed nearly exclusively on the host's forelimbs and their axillae.
体外寄生虫的成功主要取决于其宿主的附着部位和身体状况。蜱通常倾向于聚集在脊椎动物宿主的特定区域，但分布模式可能取决于宿主的体型、状况、性别、生命阶段或皮肤形态。在此，我们研究了蜱在蜥蜴身上的分布情况，并检验了以下假设：蜱的出现或高丰度局限于鳞片较小且鳞片间长度较大的身体部位，因为这些部位应为蜱提供更好的附着条件。本研究于2008 - 2011年在波兰中部的野外条件下进行。总共捕获了500只蜥蜴（捷蜥蜴），并从它们身上采集到839只蜱（蓖麻硬蜱，幼虫和若虫）。使用广义线性混合模型，我们发现蜱在前肢及其腋窝处最为丰富，90%的蜱附着在那里。蜥蜴身体的这一部分以及后肢后面的区域覆盖着最小的鳞片，它们之间的间隙相对较宽。这并不完全支持我们的假设，即蜱更喜欢易于接触鳞片间皮肤的位置，因为这无法解释为什么后肢区域的蜱如此之少。我们发现蜱的丰度与蜥蜴体型指数（吻肛长度）呈正相关。雄性和成年蜥蜴身上的蜱丰度也高于雌性和幼年个体。自残对蜱的丰度没有影响。我们未发现蜱的大小与蜥蜴形态、性别、自残和体型指数之间存在相关性。死蜱出现的概率与蜥蜴身上蜱的总数呈正相关，但死蜱的存在与蜥蜴的大小、性别或年龄之间没有关系。因此，蜥蜴的体型和性别是影响蜱丰度的主要因素，并且这些寄生虫几乎只分布在宿主的前肢及其腋窝处。
