Serum chemistry of diseased English sole, Parophrys vetulus Girard, from polluted areas of Puget Sound, Washington

Relationships between selected serum components and microscopically detected idiopathic liver and kidney lesions were evaluated for English sole, Parophrys vetulus, sampled from urban and non-urban areas of Puget Sound, Washington. The normal range for each serum chemistry parameter was based on English sole with no lesions, or sole with minor parasitic conditions or with lesions in tissues other than liver and kidney which did not significantly affect serum chemistry values. Generally, sole with idiopathic liver lesions had significantly different haematocrit values and levels of serum albumin, calcium, and bilirubin when compared to sole which were free of idiopathic liver and/or kidney lesions. Serum aspartate aminotransferase and alanine aminotransferase activity and serum levels of glucose, total protein, phosphates and magnesium were also abnormal, but appeared to be associated only with certain types of liver lesions. No association between kidney lesions and abnormal serum chemistry values was identified. In addition, English sole sampled from some urban areas of Puget Sound had particular serum chemistry values and liver lesion prevalences which were significantly different from those of sole sampled from non-urban areas. These findings support the hypothesis that sole near highly urbanized environments may display other signs of impaired health in addition to high prevalences of tissue lesions. Thus, measurements of serum chemistry parameters, in conjunction with histopathological examination, appear to be useful techniques for evaluating the health of English sole.