Abstract

Heavily melanized gills in crustaceans, often referred to as black gill, have been reported in both wild and cultured marine species. Tissue melanization is generally the result of a response of the crustacean innate immune system to the presence of an irritant or pathogen. While black gill can be caused by a variety of abiotic stressors and nutritional deficiencies, biotic agents are the cause of most reported black gill cases in crustaceans. In high density culture systems, fungi are identified as the most common causes of black gill outbreaks. In the wild, epidemic-scale outbreaks of black gill appear largely to be caused by ciliate rather than fungal infections. Black gill epidemics caused by ciliates have recently been reported in two commercially important fishery species including penaeid shrimp in the South Atlantic Bight USA (Western North Atlantic) and the Gulf of Mexico, and in pandalid shrimp in the Gulf of Maine, USA. Here we review the reports of the occurrence, causative agents, biology, ecology, and impacts of black gill on wild crustacean species of black gill with special focus on the pandalid shrimp species Pandalus borealis parasitized by the apostome ciliate Synophrya sp. and penaeid shrimp in the Western North Atlantic and Gulf of Mexico parasitized by a newly described apostome ciliate species Hyalophysa lynni. A review of the literature reveals large knowledge gaps with respect to black gill in both commercially exploited and other keystone crustacean species. Recommendations for future research include improved surveillance and identification of causative agents of black gill, improved understanding of their interactions with crustacean hosts including distribution, transmission, morbidity, and mortality, epidemiology, molecular biology, and relationship with climate.

摘要

在野生和养殖的海洋物种中都有报道称甲壳类动物的鳃有严重的黑色素化，通常被称为黑鳃。组织黑化通常是甲壳动物先天免疫系统对刺激物或病原体的存在作出反应的结果。虽然黑鳃可由多种非生物应激源和营养缺乏引起，但生物因子是甲壳类动物中大多数报告的黑鳃病例的原因。在高密度培养系统中，真菌被确定为黑鳃爆发的最常见原因。在野外，大规模爆发的黑鳃似乎主要是由纤毛虫而不是真菌感染引起的。最近报告了由纤毛虫引起的黑鳃流行病在两种重要的商业渔业物种中，包括美国南大西洋湾（北大西洋西部）和墨西哥湾的对虾，以及美国缅因湾的熊猫虾。在这里，我们回顾了黑鳃的发生、病原体、生物学、生态学和对黑鳃野生甲壳类动物的影响的报告，特别关注熊猫虾物种由寄生纤毛虫Synophrya sp.寄生的Pandalusborealis 。和 北大西洋 西部 和 墨西哥 湾 的 对虾 被 一种 新 描述 的 寄生 纤毛虫 物种Hyalophysa lynni 寄生. 对文献的回顾揭示了在商业开发和其他主要甲壳类动物物种中关于黑鳃的巨大知识差距。对未来研究的建议包括改进对黑鳃病原体的监测和识别，更好地了解它们与甲壳类动物宿主的相互作用，包括分布、传播、发病率和死亡率、流行病学、分子生物学以及与气候的关系。