STUDIES ON THE TEMPERATURE AS A LIMITING FACTOR FOR THE SURVIVAL OF ONCOMELANIA NOSOPHORA, THE VECTOR SNAIL OF SCHISTOSOMA JAPONICUM IN JAPAN

Abstract

Oncomelania nosophora, the intermediate host of Schistosoma japonicum in Japan, is an amphibious snail with a strong resistance to its environmental conditions. While the snail is known to show a strong resistance against dryness, it is also reported to have a characteristic adapting to a wide-range of temperatures (Komiya et al., 1956) ; Saito (1951), Kawamoto (1954) and Nakao (1958), following their studies on its adaptation range of temperatures, unanimously stated that the limiting temperatnre to allow the snail active was in the range between 10°C and 28°C. However, full information is still lacking about the temperature as a limiting factor for the survival of Oncomelania nosophora. The present paper describes the results of the experiments concerned.