Fish Necropsy is a thorough examination and dissection of a dead animal’s body to determine thecause 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
鱼的状况(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)
损伤的存在
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.