It is a viral diseases caused by Borrelina virus, less common in eri silkworm.
Causes:
- High temp. & RH
- Feeding of polyhedra contaminated leaves
- Poor ventilation & sanitation
- Improper bed cleaning
- Feeding of tender & wet leaves
- Accumulation of faeces
- Overcrowding of worms
Symptoms:
- Sluggish movement
- Worms restless
- Skin shiny
- Loss of clasping power
- Hang upside down
- Intersegmental swelling
- Skin turns yellowish
- Rectal protrusion
- Soiling of anal region
Control measures:
- Effective disinfection of rearing house/ appliances
- Avoid overcrowding
- Proper sanitation & hygiene
- Avoid feeding tender leaves to maturing worms
- Proper bed cleaning
- Avoid accumulation of excreta
- Destroy diseased worms &
- Sprinkling of Bleaching powder+lime at 1:9 ratio