Role of Pathogenic Bacteria and Foreign Bodies in the Hemocyte Count of Different Races of Silkworm (Bombyx mori L.)

Comparative cellular immune responses between commercially exploited bivoltine and multivoltine races have been studied. Worms of different races are inoculated with pathogenic bacteria Staphylococcus vitulinus. Total Haemocyte Count (THC) at each post-inoculation period has been noted and compared with control groups. Bivoltines have more hemocytic concentration than that of any multivoltine races. A common behavior is observed for all races after inoculation of pathogen. The hemocyte population decreases in Ist hour, increases in 2^nd hour and again decreases in 3^rd hour. In second experiment, a multivoltine race, M₁₂W was selected and was injected with saline having silica, indigo and carbon particles and with particle free saline (0.67% NaCl). But results similar to those of the first experiment were found indicating that pathogenicity is not the cause of first 3 hours, down-up-down sequence of THC in inoculated worms.