Abstract
Infectivity of Eimeria tenella sporozoites which contained various amounts of amylopectin after incubation at different temperatures was investigated. When sporozoites were incubated at 41°C for 16hr in phosphate buffer solution, almost no amylopectin granules were seen in their bodies and no vivid movements were noted. After sporozoites were incubated at 0, 29, 37 or 41°C for 16hr, both amylopectin contents of sporozoites and rates of their invasion into cultured chicken kidney cells decreased as the temperature of incubation increased. There was a high value of the coefficient of correlation between amylopectin contents and invasion rates of the sporozoites. Lower mortality rates and smaller production of oocysts were observed in chicken embryos inoculated with sporozoites incubated at 41°C for 16hr than those in embryos inoculated with fresh sporozoites. The present results suggest that amylopectin of E. tenella sporozoites plays an important role in establishing infection, i. e. amylopectin is probably a source of energy to survive and to access, invade, and develop in their host cells.
