Gills represent one of the major sites of gas exchange of fish, consequently they are in continuous close contact with the aquatic environment and its pollutants. In the present study the effects on gills of pejerrey fish, Odontesthes bonariensis, under glyphosate-based herbicide subchronic exposure were analyzed. Adult animals were exposed to sublethal concentrations of a glyphosate-based commercial formulation (1 and 10 PMG mg L⁻¹, PMG: glyphosate active ingredient) for 15 days, while control group was maintained in rearing water. Ultrastructural changes in gills were observed by scanning electron microscopy (SEM). The composition of the surface epithelium and specific surface area were determined by energy dispersive spectroscopy (EDS) and N₂ (g) adsorption–desorption isotherms, respectively. The herbicide exposure induced severe alterations in gill ultrastructure, as shown in the SEM micrographs. Accordingly, an increase in surface area of the gills of exposed animals was determined. These results support that gills parameters of freshwater fish are sensitive morphological biomarkers for glyphosate exposure.

鳃是鱼类气体交换的主要场所之一，因此它们与水生环境及其污染物持续密切接触。在本研究中，分析了草甘膦除草剂亚慢性暴露对佩杰里鱼（ Odontesthes bonariensis）鳃的影响。成年动物暴露于亚致死浓度的基于草甘膦的商业制剂（1和10 PMG mg L ^-1 ，PMG：草甘膦活性成分）15天，而对照组则维持在饲养水中。通过扫描电子显微镜（SEM）观察鳃的超微结构变化。表面上皮的组成和比表面积分别通过能量色散光谱(EDS)和N ₂ (g)吸附-解吸等温线测定。如扫描电镜显微照片所示，除草剂暴露引起鳃超微结构的严重改变。因此，确定了暴露动物的鳃表面积的增加。这些结果支持淡水鱼的鳃参数是草甘膦暴露的敏感形态生物标志物。