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Illustrated field guide for assessing external and internal anomalies in fish

January 1, 2002

Procedures are described for processing fish for examination of external and internal anomalies and pathologies indicative of exposure to environmental contaminants and other peturbations. For the procedures described here, fish are captured (preferably by electrofishing) and held alive until processing (generally < 1 h). Fish are weighed, measured, and necropsied, and a scale sample is obtained from for age determination. Information is given for the collection and preservation of tissue samples for histopathological analysis. Photographs of most abnormalities are included along with normal conditions for easier identification of external (oral, head, eye, gill, opercula, and fin) and internal (liver, spleen, gonad, and kidney) anomalies. The report also includes recommendations for record keeping, sample labeling, and shipping records, equipment, supplies,and samples. A list of suggested equipment and supplies for field processing is included as are instructions for cleaning equipment.

Publication Year 2002
Title Illustrated field guide for assessing external and internal anomalies in fish
Authors Stephen B. Smith, Anne P. Donahue, Robin J. Lipkin, Vicki Blazer, Christopher J. Schmitt, Ronald W. Goede
Publication Type Report
Publication Subtype Federal Government Series
Series Title Information and Technology Report
Series Number 2002-0007
Index ID itr020007
Record Source USGS Publications Warehouse
USGS Organization Columbia Environmental Research Center