2002 Volume 64 Issue 3 Pages 199-200
The effect of heat treatment was examined against oocysts of Cryptosporidium parvum, Cryptosporidium muris and chicken Cryptosporidium sp. isolated in Japan. The oocysts of these species were exposed at 50, 55, 60 and 70°C for 5, 15, 30 and 60 sec in water bath, respectively. To determine the infectivity of heated oocysts, the mice and chickens were inoculated with the treated oocysts and the oocyst output in the feces after inoculation was examined. In C. parvum and chicken Cryptosporidium sp., the oocysts were not detected from mice or chickens which were received oocysts heated at 55°C for 30 sec, 60°C for 15 sec and 70°C for 5 sec. In C. muris, the oocysts were not detected from mice which were received oocysts heated at 55°C for 15 sec, 60°C for 15 sec and 70°C for 5 sec. Consequently, it was clarified that the infectivity of Cryptosporidium oocysts to mice and chickens was lost by heating at 55°C for 30 sec, 60°C for 15 sec and 70°C for 5 sec.
Journal of The Japanese Society of Veterinary Science
