Effects of waterborne Fe(II) on juvenile turbot Scophthalmus maximus: analysis of respiratory rate, hematology and gill histology

• Published in: Chinese Journal of Oceanology and Limnology
• Main Authors: Wu Zhihao, You Feng, Liu Hongjun, Liu Mengxia, Li Jun, Zhang Peijun, You, F (reprint author), Chinese Acad Sci, Inst Oceanol, Key Lab Expt Marine Biol, Qingdao 266071, Peoples R China.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2012
• Subjects: Scophthalmus Maximus; Waterborne Fe(Ii); Respiratory Rate; Hematological Parameter; Gill Structure; Limnology; Oceanography; Scophthalmus maximus; Turbot
• Online Access: http://ir.qdio.ac.cn/handle/337002/12319; https://doi.org/10.1007/s00343-012-1065-3

The concentration of Fe(II) is high in some groundwater supplies used in turbot culture, and the toxicity of waterborne Fe(II) is unknown. We investigated the stress responses of juvenile turbot, Scophthalmus maximus, exposed to Fe(II) of different concentrations (0.01, 0.05, 0.1, 0.5, 1, and 2 mg/L) for 1, 7, 14, and 28 d, under the same ambient conditions of other parameters. Changes in respiratory rate, hematological parameters, and gill structure were determined. The results show that waterborne Fe(II) did not cause severe hematological perturbation to turbot. A low-medium Fe(II) concentration (lower than 0.1 mg/L) could boost the respiratory rate, and caused no or very limited damage to fish. A high Fe(II) concentration (0.1 mg/L or higher), however, caused gill damage, such as vacuoles in branchial lamellae, epithelial necrosis, and hypertrophy of epithelial cells, and even death after extended exposure time. Therefore, excess waterborne Fe(II) and long-term exposure to Fe(II) could be responsible for poor growth and high mortality of turbot in culture. The concentration of waterborne Fe(II) in turbot culture should be kept below 0.1 mg/L.