In aquaculture, oxolinic acid (OA) is used as a second-line treatment at 12 mg/kg biomass/day for seven consecutive days. The present study evaluated the biosafety of 21 days of dietary administration of OA at 0, 12, 36, 60 and 120 mg by assessing the growth, biochemical, erythrocytic morphological and histopathological alterations and residue levels in Oreochromis niloticus. A significant dose-dependent reduction in feed intake and biomass and an increase in mortalities and erythrocytic cellular and nuclear changes were recorded. Significant elevations in plasma glucose, creatinine, alkaline phosphatase, alanine transaminase and aspartate transaminase and a decline in calcium and chloride levels were documented. The kidney, liver and intestine histoarchitecture showed mild to marked alterations. The edible tissue OA residues peaked on day 21 and decreased upon cessation of administration in all the dosing groups. The residue levels in the muscle of the recommended dose group were well within the maximum residue limit set by the European Medicines Evaluation Agency. Although the current study hinted at the safety and tolerability of OA even during long-term usage in O. niloticus in Indian conditions, care must be exercised for its aquacultural application because of its listing as a critically important medicine for humans.

中文翻译：

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尼罗罗非鱼幼鱼口服奥喹酸的安全性、耐受性和生物反应

在水产养殖中，奥索酸 (OA) 被用作二线治疗剂，剂量为 12 毫克/千克生物量/天，连续 7 天。本研究通过评估尼罗罗非鱼的生长、生化、红细胞形态和组织病理学变化以及残留水平，评估了 21 天膳食施用 0、12、36、60 和 120 mg OA 的生物安全性。记录了采食量和生物量的显着剂量依赖性减少以及死亡率以及红细胞和细胞核变化的增加。据记录，血浆葡萄糖、肌酐、碱性磷酸酶、丙氨酸转氨酶和天冬氨酸转氨酶显着升高，而钙和氯水平下降。肾、肝和肠的组织结构显示出轻度至显着的改变。所有给药组的可食用组织 OA 残留量在第 21 天达到峰值，并在停止给药后下降。推荐剂量组的肌肉中残留水平完全在欧洲药品评估机构设定的最大残留限量之内。尽管目前的研究暗示即使在印度条件下长期使用尼罗罗非鱼，OA也具有安全性和耐受性，但由于其被列为对人类至关重要的药物，因此在水产养殖应用中必须小心谨慎。