Laboratory of Entomology, Tropical Pathology Research Institute/Oswaldo Cruz Foundation, Porto Velho, Rondonia, Brazil.
Malar J. 2012 Aug 2;11:261. doi: 10.1186/1475-2875-11-261.
The incidence of malaria in the Amazon is seasonal and mosquito vectorial capacity parameters, including abundance and longevity, depend on quantitative and qualitative aspects of the larval diet. Anopheles darlingi is a major malaria vector in the Amazon, representing >95% of total Anopheles population present in the Porto Velho region. Despite its importance in the transmission of the Plasmodium parasite, knowledge of the larval biology and ecology is limited. Studies regarding aspects of adult population ecology are more common than studies on larval ecology. However, in order develop effective control strategies and laboratory breeding conditions for this species, more data on the factors affecting vector biology is needed. The aim of the present study is to assess the effects of larval food quantity on the vectorial capacity of An. darling under laboratory conditions.
Anopheles darlingi was maintained at 28°C, 80% humidity and exposed to a daily photoperiod of 12 h. Larvae were divided into three experimental groups that were fed either a low, medium, or high food supply (based on the food amounts consumed by other species of culicids). Each experiment was replicated for six times. A cohort of adults were also exposed to each type of diet and assessed for several biological characteristics (e.g. longevity, bite frequency and survivorship), which were used to estimate the vectorial capacity of each experimental group.
The group supplied with higher food amounts observed a reduction in development time while larval survival increased. In addition to enhanced longevity, increasing larval food quantity was positively correlated with increasing frequency of bites, longer blood meal duration and wing length, resulting in greater vectorial capacity. However, females had greater longevity than males despite having smaller wings.
Overall, several larval and adult biological traits were significantly affected by larval food availability. Greater larval food supply led to enhance larval and production and larger mosquitoes with longer longevity and higher biting frequency. Thus, larval food availability can alter important biological traits that influence the vectorial capacity of An. darlingi.
亚马逊地区的疟疾发病率具有季节性，蚊媒的传播能力参数，包括丰度和寿命，取决于幼虫饮食的定量和定性方面。致倦库蚊是亚马逊地区的主要疟疾传播媒介，占波多韦柳地区存在的全部按蚊种群的>95%。尽管它在传播疟原虫寄生虫方面很重要，但对其幼虫生物学和生态学的了解有限。关于成蚊种群生态学方面的研究比幼虫生态学方面的研究更为常见。然而，为了为该物种制定有效的控制策略和实验室繁殖条件，需要更多关于影响媒介生物学的因素的数据。本研究的目的是评估在实验室条件下，幼虫食物数量对致倦库蚊传播能力的影响。
按蚊在 28°C、80%湿度和 12 小时日光照周期下饲养。幼虫分为三个实验组，分别喂食低、中、高三种食物量（基于其他库蚊物种的食物消耗量）。每个实验重复六次。成虫也暴露于每种类型的饮食，并评估了几个生物学特性（例如寿命、叮咬频率和存活率），这些特性用于估计每个实验组的传播能力。
给予较高食物量的组观察到发育时间缩短，而幼虫存活率增加。除了寿命延长外，增加幼虫食物量与增加叮咬频率、延长血餐持续时间和翅膀长度呈正相关，从而提高了传播能力。然而，尽管雌性的翅膀较小，但它们的寿命比雄性长。
总的来说，几个幼虫和成虫的生物学特征都受到幼虫食物供应的显著影响。更多的幼虫食物供应导致幼虫和产量增加，并且蚊子更大，寿命更长，叮咬频率更高。因此，幼虫食物供应可以改变影响致倦库蚊传播能力的重要生物学特征。
