Infectious Hepatopancreatic and Lymphoid Organ Necrosis (IHLN) is a viral disease that affects shrimp’s hepatopancreas and lymphoid organs. It has a high death rate and costs the aquaculture industry a lot of money. The disease is caused by small, single-stranded, non-enveloped RNA viruses called IHHNV (Infectious Hypodermal and Hematopoietic Necrosis Virus).
These viruses spread through infected shrimp or water that has been contaminated. When shrimp are infected, they get tired, lose their appetite, and their liver and pancreas change color. IHLN is thought to be one of the worst diseases for shrimp farms. Steps have been taken to stop it from spreading, like using shrimp without certain pathogens, improving biosecurity, and finding it early.
Infectious Hepatopancreatic and Lymphoid Organ Necrosis in Shrimp (Prawn)
The Pathogen Responsible for Infectious Hepatopancreatic and Lymphoid Organ Necrosis (IHLN)
- The pathogen responsible for Infectious Hepatopancreatic and Lymphoid Organ Necrosis (IHLN) in shrimp is a group of small, non-enveloped, single-stranded RNA viruses called Infectious Hypodermal and Hematopoietic Necrosis Virus (IHHNV).
- This virus is the primary cause of the disease, which affects the hepatopancreas and lymphoid organs of shrimp, causing significant mortality rates and economic losses.
- The disease predominantly affects the Tiger Shrimp species, scientifically known as Penaeus monodon. IHLN is considered a major threat to shrimp aquaculture, and efforts are being made to control its spread through various measures such as early detection methods, improved biosecurity, and specific pathogen-free shrimp.
Spread and Transmission of Infectious Hepatopancreatic and Lymphoid Organ Necrosis (IHLN) in Shrimp
- Shrimp often get Infectious Hepatopancreatic and Lymphoid Necrosis (IHLN) through other diseased shrimp or contaminated water.
- IHHNV, the causative agent of the disease, infects and replicates within the hepatopancreas of shrimp, causing tissue destruction and organ failure.
- The virus is released into the water and can infect other shrimp that swim through it. Furthermore, the illness can be passed on from sick mother shrimp to their young, a process is known as vertical transmission.
- Disinfecting tanks and equipment, instituting biosecurity rules, and selecting pathogen-free shrimp are all viable options for halting the spread of IHLN.
What are the Signs and Symptoms of Infectious Hepatopancreatic and Lymphoid Organ Necrosis (IHLN) in Shrimp
- Light pinkish to yellowish discoloration of the cephalothorax region.
- Fouling by ciliate protozoa such as Zoothamnium.
- Highly decayed (necrotic) and blackened (melanized) hepatopancreas.
- Association with secondary bacterial infections such as Vibrio alginolyticus.
- Lethargy and anorexia in affected shrimp.
- High mortality rates, especially in post-larvae and juvenile stages.
- Reduced growth and development in surviving shrimp.