As the main stocking season begins in the brackish-water shrimp farming areas of the Mekong Delta, good preparation of seedstock, stocking time, and farming techniques is no longer the only factor that ensures success. In addition, preventing dangerous diseases in brackish-water shrimp farming plays a decisive role in reducing losses and improving production efficiency. Vemedim will share practical technical measures to help farmers take a more proactive approach in caring for healthy shrimp stocks and aiming for a successful crop below.
1. White spot disease – A common dangerous disease in brackish-water shrimp farming
White spot disease is one of the most dangerous diseases in shrimp farming. Infected shrimp often turn pinkish-red and show a marked reduction in feed intake. White circular spots appear under the shell, concentrated on the cephalothorax and the last abdominal segment. The shrimp swim sluggishly, gather along the pond edges, and often die quickly, with mortality rates reaching 90–100% within just 3–7 days.
Early prevention measures:
- Use healthy, high-quality seedstock.
- Maintain good pond water quality and avoid environmental shock.
- Clean the pond, regularly siphon the bottom, and use probiotics to limit virus spread.
>> See more:
- White spot disease in shrimp – Causes and treatment
- Hepatopancreatic necrosis in shrimp – Causes, prevention, and treatment measures
2. Acute hepatopancreatic necrosis syndrome (AHPNS/EMS)
The disease appears around 10–45 days after stocking. Initially, symptoms are not clear; shrimp grow slowly, become sluggish, stop eating, and die sporadically. As the disease progresses, shrimp develop soft shells, the hepatopancreas becomes swollen or atrophied, hepatopancreatic tissue degenerates, and hepatopancreatic cells become dysfunctional and slough off. In the final stage, secondary bacterial infections often occur.
Early prevention measures:
- Follow the seasonal stocking schedule and choose high-quality seedstock.
- Thoroughly prepare the pond, apply lime, till the bottom, and treat any residual chemicals.
- Use appropriate feed and probiotics, and avoid feed waste.
- Do not use banned chemicals or eradication agents to treat the pond.
- Treat with Vemedim Vime - FDP (S) - for hepatopancreatic necrosis in shrimp
3. White feces disease
The main causes are Vibrio bacteria, the microsporidian Plexstophora, environmental factors, high stocking density, and unfavorable weather. Infected shrimp often have white feces, eat less, have intestines not full of feed, thin shells, and stunted bodies. The disease usually appears from April to October depending on the area and farming stage (40–90 days).
Early prevention measures:
- Prepare a clean pond from the beginning of the season, limit fresh feed, and avoid moldy feed.
- Closely manage the pond environment and change water periodically.
- Use probiotics to clean the environment.
- Supplement digestive probiotics, vitamins, and minerals to improve shrimp health.
- Remove dead shrimp from the pond, use Vime-clean as directed, and avoid overusing antibiotics.
4. Disease caused by Vibrio bacteria
Shrimp infected with Vibrio often show broken antennae, gill rot, black spots, a pinkish-red body color, and loss of appetite. This dangerous disease in brackish-water shrimp farming can cause rapid death or make shrimp grow slowly, become uneven in size, and develop soft shells.
Early prevention measures:
- Maintain good pond water quality, avoid overly high stocking density, and prevent shrimp injury.
- Use the probiotics Vemedim Bitech Yucca and Vemedim Aqua Bacillus periodically to reduce organic matter in the pond.
- Reduce water salinity to 15–20‰ to limit Vibrio growth.
- Supplement shrimp with vitamins C, A, and E, and use products that support molting stimulation.
- Treat with Vemedim DOXY 500 - for disease caused by Vibrio alginolyticus.
5. Filamentous bacterial disease
This usually occurs in ponds with high stocking density and lots of organic matter. Symptoms include gray or black gills, legs covered with fine filaments, shrimp swimming at the surface, failure to molt, and scattered deaths. The main cause of this dangerous disease in brackish-water shrimp farming is Leucothrix mucor and some other filamentous bacteria.
Early prevention measures:
- Improve environmental conditions, siphon the bottom, and change water.
- Manage stocking density and use the probiotic Vemedim Aqua Bacillus to reduce organic matter.
- Supplement vitamins C, A, E, and Beta-Glucan to boost resistance.
- When the disease is severe, use Saponin or KMnO4 at the recommended dose to stimulate molting and treat the pond.
6. Soft-shell disease in whiteleg shrimp
Soft-shelled shrimp have a dull color, shells that separate from the flesh, weakness, are easily attacked by harmful organisms, grow slowly, and lose commercial value. The causes are calcium and phosphorus deficiency, polluted water, or phosphorus deficiency.
Early prevention measures:
- Manage the pond environment and maintain alkalinity at 80–160 mg/l using lime or dolomite.
- Supplement minerals and premix in the feed with Anti Shock or Herbal Pro.
7. Black gill disease
This dangerous disease in brackish-water shrimp farming is commonly seen in whiteleg shrimp from the second month of culture onward. The shrimp gills turn brown or black, respiration becomes difficult, shrimp swim at the surface, gather along the pond edges, and die sporadically or in large numbers. The main causes are dirty ponds, polluted bottoms, accumulated organic matter, algal crashes, and high NH3 and NO2 levels. Early prevention measures:
- Use the probiotic Vemedim BKC 80% to clean the pond bottom and absorb toxic gases.
- Add vitamin C to the feed.
- Change the bottom water layer when conditions allow.
Thus, proactively preventing and early controlling dangerous diseases in brackish-water shrimp farming not only helps reduce mortality rates but also improves livestock efficiency and profits for farmers. The important thing is to maintain a stable water environment, choose quality seedstock, apply standard care procedures, and handle abnormalities promptly when detected. With support and solutions from Vemedim, farmers can feel more assured and aim for a successful, efficient, and sustainable crop. Contact Vemedim now for advice!
