Ecotoxicology and Environmental Safety

Giant freshwater prawn Macrobrachium rosenbergii is an economically important species. However, its growth retardant have brought serious economic losses in recent years. Antibiotics abuse is suggested as a reason for M. rosenbergii 's growth retardant , while few studies focused on the toxic effect of antibiotics on M. rosenbergii . To investigate the effect of enrofloxacin , a widely used antibiotic, on juvenile M. rosenbergii , a 14 days exposure study was carried out within 0.2, 1 and 5 mg/L enrofloxacin and followed by 7 days decontamination . Results showed that during the test period, enrofloxacin had the largest accumulation in juvenile shrimp at day 3, and gradually decreased at day 7 and 14, and almost all the drugs are cleared after 3 days decontamination. Short-term exposure to low dose enrofloxacin can promote the growth of juveniles. High dose enrofloxacin inhibited the growth of juvenile shrimp , to gill and liver damage, and induced apoptosis of the hepatopancreatic cells. These adverse effects was possibly caused by enrofloxacin-induced oxidative stress . Moreover, we also found the damage caused by high concentrations of enrofloxacin was irreversible in the short term. Collectively, these data indicated that enrofloxacin did affect the juvenile shrimp growth and development, and high level enrofloxacin abuse may contributed to M. rosenbergii 's growth retardant.

Excessive use of enrofloxacin leads to growth inhibition of juvenile giant freshwater prawn Macrobrachium rosenbergii