The effect of feeding silk worm with feeds having different protein levels on performance, cocoon quality, silk yield and silk quality

This research was carried out to determine the effects of feeds having different protein levels on some performance parameters, cocoon and yarn qualities of silkworms (Bombyx mori L.). In this study, 4000 seeds (MxN hybrids) were taken and the feeding study with the larvae hatching from the seeds was started. Five groups were arranged to contain 120 larvae in each group. Each group has 5 replications. The first group feed contains 20% crude protein and 92,30% mulberry leaf flour and is not enriched in any nutrients. In the second group, mulberry leaf flour was reduced to 77,37%, and the crude protein level was kept at 20%, but it was enriched with nutrients. Mulberry leaf flour was added to the 3rd,4th and 5th group feeds at the levels of 72,53%, 67,54 and 62,74%, respectively, and the crude protein levels were adjusted to 21, 22 and 23%, respectively and the feeds were also enriched in nutrients. In the group that consumed feed having 20% crude protein and 92,30% mulberry leaf flour, which was not enriched in nutrients, all larvae died in the 3rd instar period. Increasing feed protein level by reducing mulberry leaf meal in feed, performance (live weight, weight gain, length, width and survival percentage, amount of feed consumed, amount of digested feed), cocoon weight and cocoon quality (cocoon shell weight, cocoon brightness, feed cocoon effective conversion rate), and silk yield and silk quality (filament length and denier) increased linearly. Apparent dry matter digestibility, reference ratio and digestibility were not affected by the protein level in the feed. The increase in protein level in the feed led to a decrease in the feed conversion efficiency rate. In this study, it was concluded that the larvae performance increased, and the amount and quality of the cocoon, silk yield and silk quality were improved in feeding with 62,74% mulberry leaf meal and 23% crude protein level.