| Popis: |
In the previous paper, it was judged that nitrite poisoning was a representative cause of methemoglobinemia (MHb-emia) of Japanese eels (Anguilla Japonica). But in the fish culture ponds, there may be present many other poisoning substances such as ammonia, sulfide and the like. The present paper biochemically and histopathologically deals with the effects of these poisoning substances to the occurrence of MHb-emia of Japanese eel. Experiment 1. The ells exposed to nitrite exhibited MHb-emia. The histopathologically characterristics were similar to those of the previous paper. Experiment 2-1. The eels exposed to nitrite, ammonia and nitrate exhibited MHb-emia and severe anemia. The anemia was caused by the distruction of erythrocytes, so this anemia is erythronoclastic anemia. Experiment 2-2 and 2-3. The eels were exposed to nitrite, ammonia and nitrate. Some of the fishes got MHb-emia but almost of them showed no changes. Experiment 3. The eels were exposed to nitrite, ammonia, nitrate, sodium sulfite and sodium sulfate. Numbers of poikilocytes having needle crystal were observed in the blood smear from the eels after exposure to nitrite, ammonia, nitrate and sulfate. It seemed that there were seasonal changes about the occurrence of MHb-emia induced by exposure to nitrite. From winter to spring the eels seemed to get MHb-emia more easily than summer time. |
