Loose shell syndrome is one of the chronic diseases of shrimp. This is a condition of shrimp where the shell turns into soft and loose covering over the muscles. LSS is formed due to various factors, mainly the poor pond condition and management. Affected shrimp are lethargic, spongy, and flaccid; feed poorly; and show a gap between the muscle and the shell. Occasionally they have a pinkish discoloration of the branchiostegite, pleopods, and lower abdominal segments. Farmers also sometimes report a whitening of the abdomen in shrimp before the onset of LSS.
The affected shrimps can be identified with
- Soft muscle, and a gap between muscle and exoskeleton,
- Pigmented hepatopancreas
- Muscle gills are damaged, and fouling in the gill makes respiratory problems.
- Behavioral changes like off-feeding,
- Lose of weight,
- Reduction in daily growth rate,
- Impaired molting and progressive mortality
Loose shell can be controlled with feed supplements with phospholipids, fatty acids, antioxidants, chelated minerals, vitamins and amino acids, liver stimulants. Calcium nanoparticles helps to regain shell of the shrimps and bounce back shrimp growth.