Liver, reproductive glands, intestines and blood are not edible.

The size of the poisonous content of the liver, reproductive glands, intestines, stomach and blood, etc. varies with different breeding environments and seasonal changes. According to the examples of the Yangtze River Puffer and artificially cultured Pufferfish, the toxicity of each organ is compared as follows: ovary→spleen→liver→blood tendons→eyes→gill rakers→skins→sperm nodes→muscle. The comparison of toxicity of organs of cultured river herring (above 2 years old) is consistent with that of wild river herring, but with lower toxin content.

The toxins of river herring are mainly distributed in ovaries and liver, followed by kidneys, blood, eyes, gills and skin; while spermathecae and muscles are non-toxic.

Extended information;

The pufferfish is usually raised in a pool, before eating it, the pufferfish will be netted out with a mesh net, the fins will be cut off with a knife, the mouth will be removed, the eyes will be gouged out, and the skin will be peeled off, and the belly will be cut open to take out the intestines, the liver, the ovaries and the kidneys and other internal organs that contain high levels of toxins, and then the flesh of the pufferfish will be put into the clean water in small pieces to rinse away the top of it. The poisonous juice will be rinsed clean.

The cleaned pieces of fish are white and crystal clear. The fish is then cut into paper-thin slices and arranged in the shape of chrysanthemums or cranes.

The river herring has a mixed diet, feeding on fish, shrimp, crabs and shellfish, as well as insect larvae, branchiopods, copepods, and leaves of higher plants and filamentous algae. It generally ingests very little during its reproductive migrations.

Source of reference; Baidu Encyclopedia-Pufferfish