Napoli Ettore, Falsone Luigi, Gaglio Gabriella, Colella Vito, Otranto Domenico, Giannetto Salvatore, Brianti Emanuele
Dipartimento di Scienze Veterinarie, Università degli Studi di Messina, Polo Universitario Annunziata, 98168 Messina, Italy.
Dipartimento di Medicina Veterinaria, Università degli Studi di Bari, Str. prov. per Casamassima km 3, 70010 Valenzano, Bari, Italy.
Vet Parasitol. 2016 Jul 30;225:1-4. doi: 10.1016/j.vetpar.2016.05.020. Epub 2016 May 17.
The laboratory maintenance of parasitic life cycles is crucial to support research in many fields of parasitology. The land snail Helix aspersa (syn. Cornu aspersum), an intermediate host of feline lungworms Aelurostrongylus abstrusus and Troglostrongylus brevior, is adopted to produce infective stages of those nematodes in laboratory condition. The aim of this study was to compare the most common methods of experimental infection of H. aspersa with first stage larvae (L1) of A. abstrusus (i.e., contact of the snail foot with the L1) with the injection of these larvae in the foot of the snail, instrumental to reduce the infection time and to maximize the output of third-stage larvae (L3). Three groups (i.e., A, B, C) of 15 H. aspersa snails were infected with L1 of A. abstrusus (n=250 for each snail), whereas a fourth group (group D) was not infected (control). Snails were individually placed for 48h on a microfilm containing L1 (group A), on a potato slice previously irrigated with a suspension of L1 (group B), or they were inoculated by injection of L1 in the posterior-ventral portion of the foot (group C). Eighteen days after the infection all snails were analyzed and tissues were digested to recover L3. No difference in mortality rate was recorded among snail groups and the mean number of retrieved L3 was significantly larger in group C (71.5±52.9) compared to group B (38.2±44.9; p=0.0161) and group A (19±23.3; p<0.0001). The injection of A. abstrusus L1 in the foot of H. aspersa proved to be a fast, easy to apply and effective method, resulting in the largest number of infective larvae retrieved.
维持寄生虫生命周期的实验室培养对于支持寄生虫学许多领域的研究至关重要。陆地蜗牛皱疤坚螺（同物异名：玉米螺）是猫肺线虫隐匿猫圆线虫和短尾后圆线虫的中间宿主，被用于在实验室条件下生产这些线虫的感染阶段。本研究的目的是比较皱疤坚螺实验感染隐匿猫圆线虫第一期幼虫（即蜗牛足部与第一期幼虫接触）与将这些幼虫注射到蜗牛足部这两种最常用方法，以缩短感染时间并使第三期幼虫（L3）产量最大化。三组（即A、B、C组）各15只皱疤坚螺感染了隐匿猫圆线虫的第一期幼虫（每只蜗牛250条），而第四组（D组）未感染（作为对照）。蜗牛被分别放置在含有第一期幼虫的微膜上48小时（A组），放置在预先用第一期幼虫悬液浇灌过的土豆片上（B组），或者通过将第一期幼虫注射到足部后腹部分进行接种（C组）。感染18天后，对所有蜗牛进行分析，并消化组织以回收第三期幼虫。各蜗牛组之间未记录到死亡率差异，与B组（38.2±44.9；p = 0.0161）和A组（19±23.3；p<0.0001）相比，C组回收的第三期幼虫平均数量显著更多（71.5±52.9）。将隐匿猫圆线虫第一期幼虫注射到皱疤坚螺足部被证明是一种快速、易于应用且有效的方法，可回收最多数量的感染性幼虫。
