Troglostrongylus brevior, a lungworm affecting wild felids, has been increasingly reported in domestic cats from Europe. Troglostrongylosis is a relevant disease that may result in a potentially life-threatening bronchopneumonia, especially in kittens. The life cycle of T. brevior is indirect with terrestrial gastropods acting as intermediate host. The widely distributed spread land snail Cornu aspersum (former Helix aspersa) is competent for T. brevior development and may transmit the nematode in natural conditions. The present study evaluated the larval development of T. brevior in C. aspersum at two different environmental temperature conditions, with a focus on the effect of hibernation. One hundred and seventy snails were infected with 500 first stage larvae (L1) of T. brevior and kept in vivaria at 25 ± 2 °C. Fifteen days post infection (p.i.), 20 specimens were digested to evaluate the overall larval developmental rate from L1 to L3 (2.5 % on days 15 p.i.) and then the snails were divided in two groups, i.e. G1 kept at 25 ± 2 °C and G2 that were hibernated at 4 ± 2 °C. The developmental rate of T. brevior was evaluated in these groups on 30 and 60 days p.i. by snail digestion at each time-point. An additional batch of 40 snails (G2-1) was hibernated on D15 and digested on D60. Larvae recovered were morphologically and morphometrically examined. The infective third larval stage (L3) was detected in the muscular foot of C. aspersum at different rates depending on the environmental temperature. In particular, T. brevior showed a higher developmental rate in hibernated snails (G2: 6.9 % and 14.1 % on days 30 and 60 p.i; G2-1: 4%; G2 + G2-1 overall mean percentage: 9%) compared to non-hibernated snails (G1: 4% and 5.2 % on days 30 and 60 p.i.), indicating that lower temperatures may positively influence the developmental in C. aspersum. These data are suggestive for a seasonal pattern of T. brevior infections under field conditions, with snails containing higher parasitic burdens after their natural hibernation occurring in winter. Studies on the larval development of T. brevior in other mollusc species in field surveys evaluating differences in developmental rates and transmission patterns in different seasons are warranted.

中文翻译：

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冬眠对蜗牛蜗牛Cornu asperum中Troglostrongylus brevior幼虫发育的影响。

Troglostrongylus brevior，一种影响野生猫科动物的肺虫，在欧洲的家猫中越来越多地被报道。杆状毛虫病是一种相关疾病，可能导致威胁生命的支气管肺炎，尤其是在小猫中。T. brevior的生命周期是间接的，陆生腹足纲动物充当中间宿主。分布广泛的地蜗牛螺（Cornu aspersa）（前螺旋螺（Helix aspersa））可以胜任短螺旋体的生长，并可能在自然条件下传播线虫。本研究评估了在两个不同的环境温度条件下曲霉梭菌幼虫的发育，重点是冬眠的影响。用500头短螺旋体的初生幼虫（L1）感染了一百零七只蜗牛，并保存在25±2°C的活体内。感染后十五天 ），消化20个标本以评估从L1到L3的总体幼体发育率（在pi 15天时为2.5％），然后将蜗牛分为两组，即G1保持在25±2°C且G2保持在25°C 4±2°C。通过在每个时间点进行蜗牛消化，分别在pi的30天和60天评估这些组中T.brevior的发育率。在D15冬眠另一批40只蜗牛（G2-1），并在D60上进行消化。对回收的幼虫进行形态学和形态学检查。根据环境温度，在曲霉梭菌的肌肉足中检测到感染性第三幼虫阶段（L3）。尤其是，短尾锥虫在冬眠蜗牛中显示出更高的发育率（G2：pi 30天和60天时分别为6.9％和14.1％; G2-1：4％; G2 + G2-1总平均百分比：9％）与未冬眠的蜗牛相比（G1：在pi 30和60天时分别为4％和5.2％），这表明较低的温度可能会对C. aspersum的发育产生积极影响。这些数据暗示了田野条件下短螺旋体感染的季节性模式，蜗牛在冬季自然冬眠后含有较高的寄生虫负担。有必要在野外调查中研究其他软体动物物种中短螺旋体幼虫的发育，以评估不同季节的发育速率和传播方式的差异。冬季自然休眠后，蜗牛的寄生虫负担更高。有必要在野外调查中研究其他软体动物物种中短螺旋体幼虫的发育，以评估不同季节的发育速率和传播方式的差异。冬季自然休眠后，蜗牛的寄生虫负担增加。有必要在野外调查中研究其他软体动物物种中短螺旋体幼虫的发育，以评估不同季节的发育速率和传播方式的差异。