Shrimp farming always faces many dangerous diseases, among which shrimp hepatopancreatic necrosis disease (AHPND) is one of the most devastating causes of loss. The disease often causes early mortality and mass die-offs, reducing productivity and causing serious economic damage to farmers. Let’s join Vemedim in understanding the causes and applying proper preventive and treatment measures to help farmers protect healthy shrimp stocks, stabilize production, and develop sustainable farming.
Learn more about shrimp hepatopancreatic necrosis disease
Shrimp hepatopancreatic necrosis disease is also known as Early Mortality Syndrome (EMS), and is one of the most dangerous diseases affecting farmed shrimp today. The main causative agent is the bacterium Vibrio parahaemolyticus, a species that thrives in polluted or poorly managed pond environments.
When shrimp become infected, the hepatopancreas—the important organ that helps shrimp digest food and metabolize nutrients—suffers severe damage, leading to mass early mortality and heavy losses for farmers. Hepatopancreatic necrosis is usually divided into two main stages depending on when the disease appears:
Stage 1: Shrimp die before 35 days of age
The cause usually stems from poor-quality seed stock. In many cases, shrimp already carry the pathogen from the hatchery; when stocked into the pond and exposed to unfavorable conditions (temperature changes, dirty environment), they develop the disease and die quickly.
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Stage 2: Shrimp die from 35–60 days of age
At this stage, the disease is often related to unstable pond conditions: acidic water, organic pollution, dirty pond bottoms, or improper management and care, which allow pathogens in the pond to multiply strongly and attack the shrimp.
Symptoms and signs of shrimp hepatopancreatic necrosis
Shrimp hepatopancreatic necrosis often appears more frequently during the rainy season, especially in the first month after stocking. Since the shrimp are still small and have weak resistance, the disease is very difficult to detect with the naked eye in the early stage.
- Clinical signs:
- Shrimp swim weakly, sluggishly, often gather near the pond edge or sink to the bottom quickly.
- The hepatopancreas is swollen and soft, pale in color or shrunken, sometimes hardened and turning dark.
- The shrimp gut is empty, with little feed, and the shell is soft or translucent.
- The shrimp body becomes cloudy, feed intake decreases, and they die sporadically before spreading rapidly through the pond.
- Visual observation:
Compared with healthy shrimp, diseased shrimp have a pale yellow or gray-brown hepatopancreas with uneven coloration. If dissected for inspection, partial or complete destruction of the hepatopancreas may be seen—a characteristic sign of the disease.
How to prevent and treat shrimp hepatopancreatic necrosis disease
Once hepatopancreatic necrosis disease occurs, treatment is almost ineffective because shrimp do not have a specific immune system and stop eating as the disease progresses. Therefore, prevention is always better than treatment in shrimp farming.
How to prevent shrimp hepatopancreatic necrosis disease
To proactively prevent shrimp hepatopancreatic necrosis disease, farmers should implement the following measures well:
- Choose healthy shrimp seed from a clear source, tested and free of pathogens.
- Strictly manage pond water quality, regularly checking pH, alkalinity, and dissolved oxygen. Keep pH stable at 7.5–8, alkalinity at 100–150 ppm, and oxygen always >4 ppm.
- Periodically add probiotics (such as EM-AQUA) to balance the microbiota, decompose organic matter, and limit harmful bacteria.
- Strengthen shrimp resistance by supplementing vitamin C (Nova C) to help shrimp stay healthy, molt well, and resist stress.
- Periodically disinfect the pond with Nova Dine or BKC 800, then reapply probiotics after 2–3 days to restore beneficial microbiota.
- Manage feed properly, avoiding excess feed that pollutes the pond bottom. When the weather is bad, reduce feeding to limit stress and the risk of disease.
- Purchase and use Enter Lactyl plus (shrimp) - a water probiotic product that supplements beneficial live microorganisms and digestive enzymes for shrimp.
Treatment when shrimp are already infected
When shrimp show signs of hepatopancreatic disease, action must be taken quickly and correctly to limit losses.
- Mild case (infection rate 10–30%)
- Stop feeding for 2–3 days to stabilize pond conditions.
Day 1: Use Nova Dine to disinfect the entire pond.
Day 2: Mix Nova Oxytetra 500 (3–4 g/kg of feed) or mix Hepan Tonic (5 g/kg of feed), feed twice a day, continuously for 10 days.
(shrimp) - Supports the treatment of liver and pancreas diseases - Helps shrimp stay healthy and eat more.
Day 3: Continue using antibiotics and add probiotics, increase aeration to improve the environment.
- When shrimp show signs of recovery, continue for another 5–7 days to ensure full stabilization.
- Severe case (infection rate >60%)
- If the shrimp are small, the pond should be destroyed with chlorine (Niclon 7000G) before draining the water to prevent spread to other ponds.
- If the shrimp are large (over 40 days old), they can be harvested early, then the pond water should be treated with chlorine before discharge into the environment to ensure biosecurity.
The disease shrimp hepatopancreatic necrosis is a major threat, but it can be controlled if farmers proactively prevent it, manage the environment well, and use biological products appropriately. Vemedim always accompanies farmers in every crop, providing comprehensive and safe biological solutions to effectively prevent hepatopancreatic disease and improve the quality of market shrimp. Please contact Vemedim for further advice!
