Pangasianodon hypophthalmus is one of the most important aquaculture species in Southeast Asia, with a significant contribution to the world fish basket. Like other crops, the striped catfish suffers from bacterial diseases that demand the use of antibiotics. The present study has evaluated the safety of oxytetracycline, one of the approved and commonly used antibiotics, in this species. Juvenile stages of the fish (31.16 ± 1.03 g) were administered with the antibiotic in feed at the dose rate of 80–800 mg kg⁻¹ body weight daily for 30 days, followed by 10 days of withdrawal observation. Fish health was assessed by the study of behaviour and feed intake, haematology, blood biochemistry, and histopathology. Results showed that up to 30 days of antibiotic treatment resulted in no significant toxic effects in terms of behaviour and fish mortality. However, fish suffered from reduced feed intake and hepatotoxicity evidenced by proliferative and degenerative changes of hepatocytes, and increase in AST and ALT enzyme activities, especially in 400–800 mg kg⁻¹ doses which, however, recovered after withdrawal of the drug. Although few fish died from a bacterial infection at the lowest concentration of the drug used, fish were able to mount adaptive physiological responses best at 80 mg kg⁻¹ fish dosage. The study establishes that in‐feed administration of the antibiotic oxytetracycline @ 80 mg kg⁻¹ fish biomass is safe for therapeutic use in P. hypophthalmus.

中文翻译：

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潘加西亚诺氏眼球phthal中抗生素盐酸土霉素的生物安全性测定

Pangasianodon hypophthalmus是东南亚最重要的水产养殖种类之一，对世界鱼类篮子有重要贡献。像其他农作物一样，条纹cat鱼也患有细菌性疾病，需要使用抗生素。本研究评估了土霉素的安全性，土霉素是已批准的常用抗生素之一。在幼鱼阶段（31.16±1.03 g）以80–800 mg kg ^-1的剂量率在饲料中施用抗生素每天体重30天，然后停药10天观察。通过研究行为和饲料摄入量，血液学，血液生化和组织病理学来评估鱼类的健康状况。结果表明，长达30天的抗生素治疗对行为和鱼的死亡率没有明显的毒性作用。但是，鱼类的饲料摄入量减少和肝毒性降低，这表现为肝细胞增殖和退行性改变，AST和ALT酶活性增加，尤其是在400–800 mg kg ^-1剂量下，但是停药后才恢复。尽管很少有鱼在使用最低浓度的药物后因细菌感染而死亡，但在80 mg kg ^{-1的条件下}，鱼能够产生最佳的适应性生理反应鱼的剂量。该研究确定，在饲料中以80 mg kg ^-1的鱼生物量喂食抗生素土霉素可以安全地用于P的治疗。 下眼睑。