Investigation on the infection of trematode metacercariae of Channa gachus in Jinghong, Yunnan

Abstract

Objective To realize the infection of trematode metacercariaes of Channa gachus in Jinghong City and provide basis for the prevention and treatment of local fish–borne trematode diseases.

Methods The main two types of altitude and climate on behalf of Mengyang Town and Puwen Town were selected, respectively from the local farmers’ market to collect living Channa gachus back to laboratory tests. Trematode metacercariaes were collected from different parts of Channa gachus by artificial digestion and water–washing sedimentation method. The seized metacercariaes were placed under a biological microscope to further identify the species, classify and count the types and numbers of metacercariaes.

Results A total of 270 Channa gachus were investigated and 165 of them were infected. The total infection rate was 61.11%. The infection rates of Channa gachus in Mengyang Town and Puwen Town were 96.15% and 28.57%, there were significant differences in infection rates of trematode metacercariaes ( P<0.05). Metacercariaes of Haplorchis pumilio, Centrocestus formosanu and Haplorchis taichui were detected from gills, fins and muscles of Channa gachus. The infection rates of Haplorchis pumilio, Centrocestus formosanu and Haplorchis taichui were 19.39% (32/165), 50.91% (84/165) and 29.70% (49/165), respectively. The infection rates of gill, fin and other muscles of Channa gachus collected from Mengyang Town of Jinghong City were 92.31%, 34.62% and 15.38% respectively.

Conclusion In Jinghong City, the infection rate of trematode metacercariaes in Channa gachus is very high. The local government should strengthen health education on the fish–borne trematode diseases in order to raise the prevention awareness and reduce the risk of infection.

Abstract

摘要： 目的 了解景洪市南鳢感染吸虫囊蚴情况, 为制定当地鱼源性吸虫病的防治策略提供依据。 方法 选取景洪市主要的两种海拔和气候代表类型勐养镇和普文镇为调查点, 分别从当地农贸市场采集活体南鳢带回实验室检查,采用人工消化法和水洗沉淀法收集南鳢不同部位感染的囊蚴, 将检获的囊蚴置于生物显微镜下进一步鉴别虫种, 分类并统计囊蚴的种类和数量。 结果 共调查南鳢270条, 检出吸虫囊蚴感染165条, 总感染率为61.11%。勐养和普文两个调查点的南鳢吸虫囊蚴感染率分别为96.15%和28.57%, 差异有统计学意义 ( P<0.05) 。从南鳢的鳃、鳍和其他肌肉中检出钩棘单睾吸虫、台湾棘带吸虫和扇棘单睾吸虫等囊蚴, 检出率分别为19.39% (32/165) 、50.91% (84/165) 和29.70% (49/165), 其中从勐养镇采集的南鳢鱼鳃中检出率高达92.31%, 鱼鳍中检出率为34.62%, 其他部位肌肉中检出率为 15.38%。 结论 景洪市南鳢体内吸虫囊蚴的感染率较高, 当地应加大对鱼源性吸虫病防治的宣传教育, 提高人群防病意识, 降低感染风险。