National Centre for Vector Entomology, Institute of Parasitology, Vetsuisse and Medical Faculty, University of Zürich, Winterthurerstrasse 266a, 8057, Zürich, Switzerland.
Department of Evolutionary Biology and Environmental Studies, Faculty of Science, University of Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland.
J Therm Biol. 2023 May;114:103592. doi: 10.1016/j.jtherbio.2023.103592. Epub 2023 May 15.
Mosquito-borne diseases pose a major burden on humans and animals. Temperature strongly influences the physiology and life cycle of mosquitoes and also the pathogens they transmit. Thermoregulatory behaviour of mosquitoes has been addressed in a few laboratory studies. Here, we expand such studies by investigating the thermal preference when resting of Aedes japonicus, an invasive and putative vector species of many pathogens, in a semi-field setup during summers in a temperate climate. Blood-fed or sugar-fed Ae. japonicus females were released in the late afternoon in a large outdoor cage containing three resting boxes. The next morning, temperature treatments were applied to the boxes, creating a "cool" (over all experiments around 18 °C), and a "warm" (around 35 °C) microhabitat in addition to an untreated "ambient" (around 26 °C) one. The mosquitoes resting within the three boxes were counted five times, every 2 h between 9h and 17h. The highest proportions of mosquitoes (e.g. up to 21% of blood-fed ones) were found in the cool box while both blood-fed and sugar-fed mosquitoes avoided the warm box. The mean resting temperatures of Ae. japonicus were below the ambient temperatures measured by a nearby meteorological station, and this was more pronounced at higher outdoor temperatures and in blood-fed as compared to sugar-fed mosquitoes. Thus, over all experiments with blood-fed mosquitoes, the calculated average resting temperature was 4 °C below the outdoor temperature. As mosquitoes prefer cooler resting places than temperatures measured by weather stations in summer, models to predict mosquito-borne disease outbreaks need to account for the thermoregulatory behaviour of mosquitoes, especially in the wake of climate change.
蚊媒疾病对人类和动物造成了重大负担。温度强烈影响蚊子的生理和生命周期，以及它们传播的病原体。在一些实验室研究中已经研究了蚊子的体温调节行为。在这里，我们通过在温带气候的夏季在半野外设置中调查 Aedes japonicus（许多病原体的入侵和潜在载体物种）在休息时的热偏好来扩展此类研究。在一个包含三个休息箱的大型户外笼子中，傍晚时分释放饱血或糖食的雌性 Aedes japonicus。第二天早上，对箱子进行温度处理，创造了一个“凉爽”（整个实验环境温度约为 18°C）和一个“温暖”（环境温度约为 35°C）微栖息地，以及一个未处理的“环境”（环境温度约为 26°C）。在这三个箱子内休息的蚊子被五次计数，从 9 点到 17 点每 2 小时一次。在凉爽的箱子里发现了最高比例的蚊子（例如，饱血的蚊子高达 21%），而饱血和糖食的蚊子都避免了温暖的箱子。Aedes japonicus 的平均休息温度低于附近气象站测量的环境温度，并且在较高的室外温度和饱血蚊子中比糖食蚊子更为明显。因此，在所有带有饱血蚊子的实验中，计算出的平均休息温度比室外温度低 4°C。由于蚊子更喜欢较凉爽的休息场所，而不是夏季气象站测量的温度，因此预测蚊媒疾病爆发的模型需要考虑蚊子的体温调节行为，尤其是在气候变化之后。
