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Florfenicol is a new type of animal special chloromycetin drugs, with broad antimicrobial spectrum, small toxic side effect, not easy to produce drug resistance and other characteristics, are widely used in aquaculture. Florfenicol amine is the main active metabolites of florfenicol, in aquatic products in EU and China to florfenicol and florfenicol amine as the detection object. this thesis selected florfenicol as the object of study, application residue detection methods and toxicology test methods study florfenicol in the carp body residue and toxicity, for the drug in carp aquaculture provides a theoretical basis for reasonable use.To establish UPLC-MS/MS analysis method,detection of carp muscle and skin tissue of florfenicol and florfenicol amine content. Samples using alkaline extraction with ethyl acetate, water volume, hexane degreasing, concentration of ACQUIT UPLC BEH-C18column, the column temperature:40C, sample volume:10/L:0.25mL/min, velocity, acetonitrile and water as mobile phase gradient elution, multiple reaction monitoring (MRM). The results showed, in10-1000ng/mL mass concentration range, florfenicol and florfenicol amine standard linear relationship (r=0.999), florfenicol in muscle and skin in the average recovery were90.11%and92.37%florfenicol amine in muscle and skin in the average rate of recovery respectively86.40%and91.79%, the lowest detection were0.1ng/mL and0.5ng/mL. Average coefficients of variation were less than15%, meet the florfenicol and florfenicol amine drug metabolism and pharmacokinetics study requirements.The contents of florfenicol and florfenicol amine were monitored in the muscles and skins0.5h,1h,2h,4h,8h,12h,24h,2d,3d,5d,7d,10d,15d, and20d after the drug delivery. The results showed that the florfenicol in the common carp was metabolized in vivo rapidly, peak in2-4hours. There was more florfenicol and its metabolite florfenicol amine residues in the muscles than those in the skin, and the florfenicol contents in the muscles and skins higher than the florfenicol amine residues in the same tissues, showing rapid metabolism in the skin. The withdrawal period of the drug was found to be over2d according to EU standard and over10d.according to Japanese standard.With15mg/kg,30mg/kg,50mg/kg,100mg/kg dose of continuous drink carp20d. During the administration of4d,10d,15d,20d and30d detectio plasma and liver of ALT, AST, SOD, MDA, T-AOC, GSH-PX activity, as well as the liver CAT activity, BUN activity in plasmaALT activity in blood plasma and liver of100mg/kg dose group was obviously higher than control group and the SOD CAT activity in liver of100mg/kg dose group was obviously higher t han control group. ALT and SOD activity in liver of100mg/kg dose group was obviously reduce d, ALT activity in blood plasma of50mg/kg dose group BUN activity in blood plasma of100mg/kg dose group and MDAGSH-PX activity in liver of100mg/kg dose group are obviously hig her than control group20days after administration. The enzymes activity in other group are not obviously increased.AST activity in blood plasma and liver in all groups were increased, T-AOC activity were reduced. NA+K+-ATP activity in branchia was reduced, but no statistical difference.In conclusion, florfenicol has low side-effect, withdrawal time is2d in MRLS of China,10d in MRLS of Japan.
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