Each day you must handfeed them birdseed, as silkworms can never leave the barn. A healthy worm produces silk every 4 days. The quality of the silk depends on your affection with it and it's health.
Silkworms may not be brushed or picked up, but can be pet to raise affection.
Silkworms can't be bred and never age.
A healthy silkworm produces silk every 4 days and your affection and their health determine the silks quality.