Research Article: Pathological effects of Aspergillus toxicity on gill structure of Litopenaeus vannamei in Iran by two different toxicological investigations

This histological study was conducted to discover the response of Litopenaeus vannamei to various levels of aflatoxigenic fungi (Aspergillus) toxicity. For this purpose, ۴۰۰ specimens of live shrimp were gathered from a shrimp culture site in Iran. According to the results of the high-pressure liquid chromatography (HPLC) analysis, Aspergillus parasiticus had a higher production capability of total aflatoxin (TAF) (۱۰۷۳.۸۰۴ ng g-۱) compared to Aspergillus flavus (۲۹۲.۳۴۹ ng g-۱). Two experiments with different toxicities of Aspergillus were assayed. In both experiments, the shrimps in ۶ experimental groups were exposed to ۰, ۱, ۵, ۱۰, ۱۵, and ۲۰ ml of fungal spore suspension (FSS) in the feed (E۱) and culture medium water (E۲) in triplicate in each group for ۴ weeks. The histopathology results of the gill tissue in the control group were normal. However, the inflammation, hemocytic infiltration, melanization, edema, and necrosis (as the main histopathological changes in the gill tissue) were observed after ۲۸ days of the experiment when the toxicity of both experiments reached ۱۸ µg kg-۱ total aflatoxin and ۱ ml FSS in E۱ and E۲, respectively. Furthermore, it was recognized that the histological alterations index (HAI) of gill was higher in E۲ (۰-۱۳۰) than in E۱ (۰-۷۴).

Keywords:

Aspergillus parasiticus , Aspergillus flavus , Aflatoxin , Gill , Litopenaeus vannamei