关键词: 凡纳滨对虾 , 黑鳃病症, 线虫, 病理观察, Litopennaus vannamei, black-gill disease symptoms, nematodes, pathological observation

Abstract: To determine the etiology of broodstock of Lionenaeus vannamei with black-gill disease,the etiology were analyzed in sick broodstock. The results showed that a large number of nematodes were observed in the gill filament of sick broodstock Litopenaeus vannamei. The characteristics of nematodes micro - structure showed that the length of female and male of nematode were ( 983.6±16.69 ) μm and ( 956.9±412.14 ) μm, respectively. The features were cuticle heterogeneous with lateral differentiation of two longitudinal rows of dots, buccal cavity with three solid teeth,four cephalic setae, five cup-shaped precloacal supplements, amphids transversely oval and curved, and posterior oesophageal bulb not distinctly set off. According to the morphological analysis,the nematodes were identified as Chromadoridae, Chromadorella. Pathological observation showed that after the nematode parasitization, the gill tissues of broodstock were necrosis,dissolution and melanin deposition,while the swim foot base appears black layer. In conclusion,a black-gill disease in broodstock of Litopenaeus vannamei caused by nematode of genus Chromadorella was reported in this paper.