Damage of cadmium and lead to DNA chain and the effects on cocoon quality were studied in silkworm under exposure of different cadmium and lead concentrations.

uantitative analyses are made on such factors as reelable cocoon ratio, cocoon quality,cocoon cooking/silk reeling technology and management that affect silk yielding of fresh cocoons,with corresponding measures presented to improve reelable cocoon ratio,cocoon quality and cocoon cooking/silk reeling levels.

The results showed that the numbers of enzyme bands and the enzyme activity swelled in region A,hatching rate declined with increase of the dose of N +,newly hatched silkworm setae dispersion rate enhanced a little and difference of development in individual swell but cocoon quality retain.