PDF(Pubmed)
Abstract：
A number of studies have been conducted on monogenean seasonality, though primarily in continental regions with wide annual temperatures ranges. We investigated seasonal changes in the prevalence and intensity of Salsuginus seculus infesting sexually dimorphic western mosquitofish (Gambusia affinis) in New Zealand. This represents the first examination of seasonality for this species globally, and the first seasonal assessment of any monogenean population in New Zealand, a temperate country with a mild oceanic climate. Prevalence and intensity of S. seculus with respect to fish size and sex was also examined. Prevalence of S. seculus changed temporally, peaking in summer, and was strongly positively correlated with algal concentrations. This relationship may be associated with increasing food levels, leading to an increase in fish courting and mating, resulting in high numbers and close physical associations of G. affinis individuals, facilitating transmission of the monogeneans. Thus, biotic factors may be important in determining temporal changes in S. seculus prevalence in New Zealand. Female G. affinis had a significantly higher prevalence and mean intensity of S. seculus than males. Longer fish had a higher mean intensity and prevalence of S. seculus. Female G. affinis likely host disproportionately more monogeneans as they are larger than males. Alternatively, females may have a compromised immune response during reproductive periods. Overall, seasonal change was observed in S. seculus prevalence and intensity under New Zealand\'s mild climatic conditions, and the larger female G. affinis in this dimorphic species supported a greater prevalence and intensity of infestation than males.
摘要：
已经对单一季节性进行了许多研究，尽管主要在年气温范围很广的大陆地区。我们调查了在新西兰，Salsuginusseculus感染性二态西方蚊子（Gambusiaaffinis）的患病率和强度的季节性变化。这是全球对该物种季节性的首次检查，以及对新西兰任何单一物种种群的首次季节性评估，海洋气候温和的温带国家。还检查了S.seculus在鱼类大小和性别方面的患病率和强度。S.seculus的患病率随时间变化，在夏天达到顶峰，与藻类浓度呈正相关。这种关系可能与食物水平的增加有关，导致鱼类求爱和交配的增加，导致G.affinis个体的大量和密切的身体联系，促进单基因的传播。因此，生物因素在确定新西兰S.seculus患病率的时间变化方面可能很重要。女性G.affinis的S.seculus的患病率和平均强度明显高于男性。较长的鱼具有较高的S.seculus的平均强度和患病率。雌性G.affinis可能比雄性大，因此可能会容纳更多的单基因。或者，雌性在生殖期可能有免疫反应受损。总的来说,在新西兰温和的气候条件下，观察到S.seculus患病率和强度的季节性变化，在这种双态物种中，较大的雌性G.affinis比雄性支持更大的侵染患病率和强度。
