Department of Zoology and Fisheries, Faculty of Agrobiology Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, Prague, CZ 165 21, Czech Republic
Department of Zoology and Fisheries, Faculty of Agrobiology Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, Prague, CZ 165 21, Czech Republic.
J Exp Biol. 2019 Jan 3;222(Pt 1):jeb184903. doi: 10.1242/jeb.184903.
Parasites alter their host behaviour and vice versa as a result of mutual adaptations in the evolutionary arms race. One of these adaptations involves changes in host thermoregulation, which has the potential to harm the parasite and thereby act as a defence mechanism. We used a model of the brown trout () experimentally parasitised with glochidia ectoparasitic larvae from the endangered freshwater pearl mussel () to reveal whether parasitisation alters fish behavioural thermoregulation. A study using radiotelemetry temperature sensors was performed during almost one year of the parasitic stage. Glochidia-infested altered their thermoregulation through active searching for habitats with different thermal regimes. The general preference for temperatures in infested fish varied and was either above or below the temperature preferred by uninfested individuals. Infested fish also preferred different temperatures across localities, whereas uninfested fish maintained their thermal preference no matter which stream they inhabited. Glochidia further induced the expression of a behavioural syndrome among personality traits, suggesting that it might increase the probability that the fish host would occur in the glochidia temperature optimum. Our findings present the first evidence that thermoregulation plays a fundamental role in the relationship of affiliated mussels and their fish hosts. Incorporating thermoregulation as a factor in the study of this relationship can help to interpret results from previous behavioural studies, as well as to optimise management measures related to endangered mussels.
寄生虫通过进化军备竞赛中的相互适应来改变宿主的行为，反之亦然。这些适应之一涉及宿主体温调节的变化，这有可能伤害寄生虫，并因此成为一种防御机制。我们使用了一种模型，即实验性地寄生了来自濒危淡水珍珠贻贝的外寄生虫幼虫的虹鳟鱼，以揭示寄生是否会改变鱼类的行为体温调节。使用无线电遥测温度传感器进行了一项研究，在寄生阶段进行了将近一年。被粘孢子虫感染的鱼通过主动寻找具有不同热区的栖息地来改变其体温调节。受感染鱼的一般偏好温度各不相同，要么高于要么低于未受感染个体偏好的温度。受感染的鱼也在不同的地点偏好不同的温度，而未受感染的鱼则无论栖息在哪个溪流中都保持其热偏好。粘孢子虫进一步在鱼的行为特征中表达了一种行为综合征，表明它可能增加鱼宿主出现在粘孢子虫温度最佳值的概率。我们的研究结果首次表明，体温调节在相关贻贝与其鱼类宿主的关系中起着重要作用。将体温调节纳入对这种关系的研究中，可以帮助解释以前行为研究的结果，并优化与濒危贻贝相关的管理措施。
