Department of Basic Veterinary, Sichuan Agricultural University, Chengdu, Sichuan, China.
Department of Basic Veterinary, Sichuan Agricultural University, Chengdu, Sichuan, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China.
Ecotoxicol Environ Saf. 2018 Nov 30;164:131-139. doi: 10.1016/j.ecoenv.2018.08.001. Epub 2018 Aug 11.
Olaquindox as one of the effective antimicrobial agents and growth-promoting feed additives, had been widely used in animal and fish production. However, few studies have been done to unveil its possible toxic effect and tissue injury on aquatic animal. In this study, the toxic effect and underlying mechanisms of olaquindox toxicity were investigated in common carp when feed with different doses of olaquindox for 90 days. The morbidity and mortality, pathological changes, hematology parameters, residue concentration in the tissues of common carp were assessed, hepatocyte apoptosis was detected through ultrastructural observation and flow cytometry methods. The results showed that the morbidity and mortality increased with the increasing dosages of dietary olaquindox, subchronic exposure to olaquindox caused remarkably pathological changes, including congestion and bleeding, intramuscular edema, vacuolar degeneration, degeneration and deformation in renal tubules architecture, respiratory epithelium fusion and intestinal epithelial microvilli disintegration. Besides, dietary olaquindox led to significant changes in blood biochemical parameters including red blood cell, hemoglobin, alanine aminotransferase and aspartate aminotransferase, an elevated residue concentration of olaquindox was detected in liver and kidney after exposure, hepatocyte apoptosis and necrosis were observed. Moreover, insulin-like growth factor I (IGF-I) mRNA level in liver was higher than normal level with the dose below 25 mg/kg olaquindox and was lower than normal level with the dose above 50 mg/kg. Our results demonstrated that dietary olaquindox may pose subchronic toxicity and residue in fish organs and provided scientific data for the safe application of olaquindox in fish.
奥拉喹多司作为一种有效的抗菌药物和促生长饲料添加剂，已被广泛应用于动物和鱼类生产中。然而，很少有研究揭示其对水生动物可能产生的毒性作用和组织损伤。本研究以鲤鱼为实验动物，通过 90 天的喂养实验，研究了奥拉喹多司的毒性作用及其潜在机制。检测了鲤鱼的发病率和死亡率、组织病理学变化、血液学参数、奥拉喹多司在组织中的残留浓度，通过超微结构观察和流式细胞术检测肝细胞凋亡。结果表明，随着饲料中奥拉喹多司剂量的增加，鲤鱼的发病率和死亡率逐渐升高。鲤鱼在亚慢性暴露于奥拉喹多司后，出现明显的病理学变化，包括充血和出血、肌肉水肿、空泡变性、肾小管结构退化和变形、呼吸上皮细胞融合和肠上皮微绒毛解体。此外，奥拉喹多司还导致血液生化参数如红细胞、血红蛋白、丙氨酸氨基转移酶和天冬氨酸氨基转移酶发生显著变化，暴露后在肝脏和肾脏中检测到奥拉喹多司的残留浓度升高，观察到肝细胞凋亡和坏死。此外，在 25mg/kg 以下剂量的奥拉喹多司作用下，肝脏中胰岛素样生长因子 I (IGF-I) mRNA 水平高于正常水平，而在 50mg/kg 以上剂量的奥拉喹多司作用下，肝脏中 IGF-I mRNA 水平低于正常水平。这些结果表明，饲料中添加奥拉喹多司可能会对鱼类产生亚慢性毒性和残留，并为奥拉喹多司在鱼类中的安全应用提供了科学数据。
