Objective: To investigate the prevalence of parasitic infections in freshwater fish and marine fish from markets in Zhenjiang City, so as to provide the evidene for formulating targeted control measures.
Methods: Freshwater fish and marine fish were collected from farmers' markets and supermarkets in Zhenjiang City using a random sampling method. The metacercaria and larvae of parasites were detected using microscopy and the direct dissection method. The prevalence of parasitic infections was analyzed in freshwater fish and marine fish.
Results: The overall prevalence of parasite infections was 11.21% (208/1 856) in the 1 856 fish (34 species) detected from 2017 to 2020, and the prevalence was 9.81% (117/1 193) in freshwater fish and 13.73% (91/663) in marine fish. Among the 1 193 freshwater fish (23 species), high prevalence of parasitic infections was detected in Gambusia affinis (43.33%), coarse fish (32.93%) and Hemiculter leucisclus (20.20%), and there was no significant difference in the prevalence of parasitic infections among different species of freshwater fish (χ2 = 105.66, P < 0.05). Clonorchis sinensis, Metorchis orientalis and other parasite species were detected in freshwater fish, with detection rates of 0.59% (7/1 193), 1.93% (23/1 193) and 7.29% (87/1 193), respectively, and there was a significant difference in the detection of C. sinensis and M. orientalis in freshwater fish (χ2 = 8.64, P < 0.05). The prevalence and intensity of larval Anisakis infections were 13.73% (91/663) in marine fish and 3.43 parasites per fish. High prevalence of Anisakis infections was seen in little yellow croaker fish (30.28%) and hairtail (27.50%), and there was a significant difference in the prevalence of parasitic infections in different species of marine fish (χ2 = 12.93, P < 0.05).
Conclusions: Parasitic infections are prevalent in freshwater fish and marine fish from markets of Zhenjiang City, and there is a risk of parasitic infections following consumption of raw or under-cooked freshwater fish and marine fish.
［摘要］ 目的了解镇江市市售淡水鱼和海鱼中寄生虫感染情况, 为制定有针对性的防治措施提供参考依据。 方法 2017—2020年采用随机抽样调査方法, 采集镇江市部分农贸市场和超市淡水鱼和海鱼, 分别采用压片镜检法和直接解剖法检测寄生虫囊呦和幼虫, 统计不同鱼种寄生虫感染情况。结果 2017—2020年累计检测34种、1 856尾海 鱼, 寄生虫感染率为11.21%(208/1 856), 其中淡水鱼感染率为9.81%(117/1 193)、海鱼感染率为13.73%(91/663)。共 检测淡水鱼23种1 193尾, 柳条鱼(43.33%)、小杂鱼(32.93%)和餐条鱼(20.20%)寄生虫感染率较高, 各淡水鱼鱼种寄生 虫感染率差异有统计学意义(χ2 = 105.66, P <0.05)。淡水鱼中检出的寄生虫有华支睾吸虫、东方次睾吸虫和其他类寄生 虫, 检出率分别为0.59%(7/1 193)、1.93%(23/1 193)和7.29%(87/1 193), 华支睾吸虫与东方次睾吸虫检出率差异有统计 学意义(χ2= 8.64, P < 0.05)。共检测海鱼11种663尾, 异尖线虫幼虫检出率为13.73%(91/663), 其中感染率较高的鱼种 为小黄鱼(30.28%)和带鱼(27.50%), 感染度为3.43条/尾, 各种海鱼寄生虫感染率差异有统计学意义(χ2 = 12.93, P < 0.05)。结论 镇江市市售淡水鱼和海鱼中存在寄生虫感染, 人群生食或半生食有寄生虫感染的风险。.
Keywords: Freshwater fish; Marine fish; Parasite; Zhenjiang City.