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Modified-masked T-2 toxin (mT-2) formed during metabolism in edible aquatic animals may go undetected by traditional analytical methods, thereby underestimating T-2 toxicity. The effects of T-2 on growth and antioxidant capacity and histopathological changes in the hepatopancreas were studied in Pacific white shrimp Litopenaeus vannamei exposed for 20 d to 0, 0.5, 1.2, 2.4, 4.8, and 12.2 mg/kg of T-2 in their feed. The concentration of mT-2 in the hepatopancreas was detected by liquid chromatography-tandem mass spectrophotometry before and after trifluoroacetic acid (TFA) treatment that converted mT-2 to free T-2. A dose-dependent increase in mT-2 concentration was observed in the hepatopancreas. Dietary exposure to T-2 significantly decreased (P < 0.05) shrimp growth and survival rate compared with the controls. The malondialdehyde (MDA) concentration was significantly increased in shrimp exposed to feed with ≥2.4 mg/kg T-2 (P < 0.05). The antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GPx), total antioxidant capacity (T-AOC), and also glutathione (GSH) content increased in shrimp dosed with 2.4-4.8 mg/kg T-2 but declined at the highest dose (12.2 mg/kg), probably indicating an inability to cope with high concentrations of reactive oxygen species (ROS) as evident from a marked increase in MDA (P < 0.05) culminating in cellular toxicity. Histopathological changes in the hepatopancreas were dose dependent, with cell autophagy evident at the highest exposure dose. This is the first report in shrimp of a dose-dependent increase in ROS, SOD enzyme activity, and T-AOC at low T-2 exposures, and associated histopathological changes in the hepatopancreas, in response to dietary T-2. Received January 26, 2016; accepted October 9, 2016.

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We report the artificial synthesis from T-2 toxin of a type A trichothecenes complete antigen. First, 3-AcT -2 was made from T-2 following acetylation. Then 3-Ac-NEOS as a T-2 skeleton structure was synthesized by enzymolysis and identified by liquid chromatography-tandem mass spectrometry and nuclear magnetic resonance. Next, a hapten (3-Ac-NEOS-HS) was formed by modifying the C8 position of 3-Ac-NEOS using succinic anhydride method. 3-Ac-NEOS-HS-BSA/-OVA were prepared by conjugating hapten with bovine serum albumin (BSA) or ovalbumin (OVA) by carbodiimide method and identified by UV spectroscopy and sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Results showed that conjugation ratio of 3-Ac-NEOS-HS to BSA was 8.76: 1 and OVA 7.24: 1, indicating 3-Ac-NEOS-HS-BSA as a complete antigen was better. Next we used it to immunize rabbits and obtained a 1:64,000 antibody titre. In conclusion, a type A trichothecenes complete antigen was successfully synthesized, which was the foundation for antibody preparation and enzyme-linked immunosorbent assay kit development for all type A trichothecenes (parent + modified/ masked type A trichothecenes).