Laboratory of Entomology and Vectors, Department of Biologia, Universidade Federal do Maranhão - UFMA, Cidade Universitária do Bacanga, São Luís, Maranhão, Brazil.
Programa de Pós-Graduação em Ciências da Saúde da UFMA, Department of Ciências Fisiológicas, São Luís, Maranhão, Brazil.
J Med Entomol. 2021 Jul 16;58(4):1917-1925. doi: 10.1093/jme/tjab053.
Studies on experimental sand fly infection require the availability of colonies and laboratory conditions. In Brazil, Lutzomyia longipalpis (Diptera: Psychodidae) (Lutz and Neiva 1912) is responsible for the highest infection rates by Leishmania spp. and this species is one of the most suitable species for laboratory colonization. In this study, we describe a method for growing Lu. longipalpis in laboratory conditions (10 generations) from natural populations sampled from a region of high endemicity for visceral leishmaniasis in the state of Maranhão, Northeastern Brazil. Using two methods (individualized or grouped females), the colony's highest productivity occurred in the first four generations, where all stages presented with high frequency. Nonviable eggs represented more than 50% of the total eggs produced by engorged females, while pupae were more resistant to fungal contamination, with a mortality rate of only 2%. In both methods, there was a predominance of female emergence; however, the ratio between males and females did not show significant differences, IF (P = 0.8023) and GF (P = 0.1831). Using the method of individualized females, the F4 generation took the longest to appear (234 d; 64 ± 57 d); by grouped females, F3 took the longest to appear (102 d; 47 ± 20 d). This method provides sufficient numbers of insects to perform vector competence tests for Leishmania spp. that cause the cutaneous form of leishmaniasis, usually found in Lu. longipalpis sampled from the study location.
实验性沙蝇感染的研究需要有群体和实验室条件。在巴西，长须白蛉（双翅目：白蛉科）（Lutz 和 Neiva 1912 年）是导致利什曼原虫属感染率最高的物种，并且该物种是最适合实验室定殖的物种之一。在这项研究中，我们描述了一种从巴西东北部马拉尼昂州内脏利什曼病高度流行地区采集的自然种群中在实验室条件下（10 代）培养长须白蛉的方法。使用两种方法（单独或分组的雌性），在最初的四代中，群体的最高生产力发生，所有阶段的频率都很高。未受精的卵占雌蝇饱血后所产总卵的 50%以上，而蛹对真菌污染更具抵抗力，死亡率仅为 2%。在两种方法中，雌性的出现都占主导地位；然而，雌雄比例没有显著差异，IF（P = 0.8023）和 GF（P = 0.1831）。使用单独雌性的方法，F4 代出现的时间最长（234 天；64 ± 57 天）；而使用分组雌性，F3 代出现的时间最长（102 天；47 ± 20 天）。该方法提供了足够数量的昆虫来进行利什曼原虫属引起皮肤利什曼病的媒介能力测试，通常在研究地点采集的长须白蛉中发现。
