1, the first age (four to five days): the whole body is black, about four or five millimeters long.

2. Second age (three to four days): the upper half of the silkworm's body is grayish-white.

3, third age (?): the whole body becomes white. Four days): the whole body becomes white.

4, fourth age (six days): the body grayish-white, and the body becomes bigger and fatter.

5, five-year-old (?): the body becomes grayish-white. Seven to nine days): the body is translucent, from dark green to leaf green, appetite loss, the amount of food sang decreases.

Expanded:

Silkworm disease prevention notes:

1, the prevention of bacterial disease: first of all choose to pick mulberry leaves, to avoid picking insect feces contamination of mulberry leaves; secondly, to prevent the deterioration of mulberry leaves, do not pick dew mulberry, staggered midday high temperature hours picking mulberry, mulberry picking to do light picking, loosened loading, fast transport, picking back mulberry leaves to be poured out of the shake loose, can be on the upper cover of the soaked wet cloth, do not seal plastic cloth, not to be covered with a wet cloth. Do not use plastic to seal.

2, the prevention of midgut-type pus: take silkworm shed ground breeding silkworms, to control the humidity in the shed. Ground as much as possible hardened, not hardened to the full pavement membrane, to prevent the ground "moisture" to deepen the humidity in the shed.

Baidu Encyclopedia - Silkworm