Changes of Midgut Proteins of Silkworm,Bombyx mori Infected with Nosema bombycis

400 fourth instar silkworm larvae were divided into four groups.Three of them were infected with 2 ml Nosema bombycis with the concentrations of 104 sopors/mL, 106 spores/mL and 108 spores/mL respectively. The fourth group was the control. Midgut was dissected from 30 silkworm larvae at 48th hour, 96th hour and 144th hour after first feeding of fifth instar, and midgut protein was obtained for SDS-PAGE. The results showed that midgut proteins appeared different variation at different time after bombyx mori larvae infected with Nosema bombycis. And some variation of midgut protein was correlated with the concentration of the Nosema bombycis.