Acute Hepatopancreatic Necrosis Syndrome (AHPNS) or Early Mortality Syndrome (EMS), it is a dangerous disease, with an incidence rate reaching up to 90% in recent years. EMS primarily damages the hepatopancreas and digestive system of shrimp, ultimately leading to severe liver necrosis. Currently, the most common symptoms in whiteleg shrimp farming are hepatopancreatic diseases and digestive tract issues.
The hepatopancreas, also known as the digestive gland, develops from the intestine. Its main functions are to secrete enzymes, absorb and store nutrients, produce clotting factors, and metabolize various vitamins, fats, proteins, and hormones. Once the hepatopancreas has issues, it will lead to liver diseases and very serious complications.
How to protect the hepatopancreas of shrimp has become a top priority.
First, before discussing hepatopancreas protection, let's examine the causes of hepatopancreatic damage in shrimp:
1. Feed Quality: Poor feed quality and improper storage can lead to mold growth and reduced quality. Therefore, when shrimp consume such feed, it can easily affect hepatopancreatic health, and combined with external environmental stressors, it can lead to mass mortality.
2. Water Quality Issues:
Poor water quality, the factors affecting water quality are as follows:
- Microorganisms: Many microorganisms are always present in the water. Shrimp filter these microorganisms from the water to absorb nutrients and minerals. Therefore, when water quality is not suitable for microbial consumption, it can easily cause digestive tract diseases.
- Toxins: Algal toxins, bacterial toxins, fungal toxins, free radicals, ammonia nitrogen, nitrite, and other harmful substances enter the hepatopancreas via the blood circulation, increasing hepatopancreatic detoxification or causing excessive immune responses, leading to hepatopancreatic dysfunction or failure in shrimp.
Salinity changes: Salinity that is too high (>25‰) or too low (<5‰) can both have adverse effects on shrimp health. - Heavy metals: The effects of heavy metals will reduce metabolism. Toxins from heavy metals accumulated in the hepatopancreas will cause stress or directly affect health. (e) Temperature: Large daily temperature fluctuations will significantly affect osmoregulation, reduce metabolism, leading to decreased resistance and increased susceptibility to disease.
3. Improper use of hepatopancreas supplements: The unreasonable use of hepatopancreas function enhancers will cause problems that burden the shrimp's hepatopancreas.
4. Improper feeding: Feeding an inappropriate amount of feed, either too much or too little, will put digestive pressure on the shrimp's hepatopancreas, and can easily trigger, with the most common symptom being hepatopancreas swelling (often due to overfeeding).
The hepatopancreas is both an immune organ of shrimp and also performs detoxification functions. How to correctly prevent hepatopancreatic disease in shrimp (P. Vannamei)?
- Properly store feed to prevent mycotoxins
- Reasonably regulate water quality management, pay attention to salinity changes in the water, remove harmful organisms and algae from the water to create a better living environment for shrimp.
- Feed reasonably and scientifically
- Reasonably use products that enhance hepatopancreatic function.
The use of bile acids to solve hepatopancreatic problems
Enhancing the digestive and detoxification capabilities of the hepatopancreas, and improving stress resistance, this is the best way once and for all. However, conventional hepatopancreas medications can only treat superficial issues; fundamental problems cannot be resolved, and shrimp will still suffer from hepatopancreatic disease. So, what products should be used for fundamental hepatopancreas protection? The answer is bile acids (BileAcids).
The hepatopancreas is a detoxification organ, and when toxins are present in the water or feed, the organ that can be damaged is the hepatopancreas. Therefore, the hepatopancreas plays a detoxification role.
- Bile acids can bind or decompose endotoxins in the intestinal tract, preventing endotoxins from passing through the intestinal mucosal barrier via the veins into the hepatopancreas, reducing intestinal absorption of endotoxins, and enhancing the role of the intestinal barrier to prevent toxins from affecting the intestine, hepatopancreas, and even the entire shrimp body.
- Promote the secretion of a large number of hepatopancreatic cells, fungal toxins, heavy metals, and other harmful substances with the elimination of bile from the hepatopancreas, thereby reducing the damage of harmful substances to the hepatopancreas and protecting shrimp hepatopancreatic health.
- Bile acids act as signaling molecules to regulate lipid metabolism. Bile acids, as signaling molecules, activate multiple receptors in the hepatopancreas and digestive tract.
- In addition, crustaceans, especially shrimp, require cholesterol and bile acids at all stages of their development.
- As a steroid, bile acid, like cholesterol, is an indispensable nutrient for the normal growth of crustacean shrimp. Shrimp do not produce endogenous bile acids due to the absence of a gallbladder and bile secretion. Therefore, supplementing bile acids in shrimp and crab feed can effectively promote their growth.
- Bile acids also have strong anti-stress capabilities, which can improve the levels of SOD, GSH-Px, and GR, enhance survival rates, and ensure the overall health of shrimp.
Abridged translation by: Engineer Tran Cong Viet – Than Vuong Company
https://www.linkedin.com/pulse/how-control-hepatopancreas-related-diseases-penaeus-vannamei-zhang/
