Fish Necropsy is a thorough examination and dissection of a dead animal’s body to determine the cause of death. A conclusion can be reached after considering several observations.
Good observations are descriptive and systematic. Examination should include:
The fish species, including length and weight
The condition of the fish (alive, moribund or dead)
The presence of any area of coloration
The color of the gills (healthy gills are bright, cherry red)
Parasite survey (skin scrape, gill biopsy or fecal sample results)
The presence of lesions
In general, freshly dead fish should have relatively clear eyes, good coloration, red to pink gills, and should not have a bad odor. The primary respiratory apparatus in fish is the gills. The gills enable maximum extraction of oxygen from the water and removal of carbon dioxide and ammonia from the blood.