1. Current status: Bacillary necrosis of pangasius. Bacillary necrosis of pangasius (BNP) is a serious and economically important bacterial infection caused by E. ictaluri. The disease occurs in all stages of fish, although high mortalities are reported in fingerlings and juveniles. Once disease outbreaks leading to a decrease significantly in production with mortalities 100% are recorded for juveniles and 30-50% for commercial fish. 

2. Causes: 

High stocking densities, pollutants, health problems and crowding can bring on the disease. It is usually fatal, and mortality rates increase rapidly.

3. Causative agent: 

Caused by Edwardsiella ictaluri

4. Mode of disease transmission: vertical transmission, E.ictaluri enter to the host through skin, gill, food…

5. Symstoms:

+ Fish stop feeding

+ Fish swim slowly  at the surface of the water pond

+ Pale skin and gills

+The quantity of dead fish increase significantly.

6. Clinical sign: 

+ External signs at the beginning of the infection. Clinical signs are encountered immediately before death. Fish swim slowly at the surface of the water and when examined show pale color on skin and gills

+ Internal white spots 1-3mm on the liver, kidney, and spleen. In the early stage of disease infection, white spots appear on the spleen first.

7/ Prevention:

+ Choose to buy quality, healthy and disease-free fingerlings at reputable hatcheries.

 +Appropriate density of rearing 500-800 fish / m2 of. Fish ponds that were infected with Bacillary necrosis of Pangasius disease need to improve and treat carefully to ensure pathogen not exist in the pond. Some products are highly recommend by VEMEDIM:

•  Vimekon (Water Treatment – Control Pathogens in Aquaculture Pond) 

1kg/2,000m³ (To destroy and prevent virus disease);  1kg/1,100m³ (To destroy bacteria diseases) 

• BKC (against gram-positive and gram-negative bacteria, fungi, algae, and lipophilic viruses):  1 liter per 200 - 400 liters of water
• Fresh water (prevent bacterial, virus, fungi infection):1 kg/1000-1500m³ of pond water.
•  Bitech- Yucca: (Natural pond treatment for fish) 

+ Increase fish's resistance by products such as vitamins, minerals necessary for fish.

• Vime- Bitech: (Probiotic and enzyme for aquaculture): At 2-3 days before stocking: 1 kg/ 6.000-7.000 m³ of water. The first 2 months: 1 kg / 3 000 - 6 000 m³ of  water. From 3^rd month to harvest: 1 kg / 2 000 - 4 000 m³ of water.
• Prozyme for fish: (Supplyment enzyme and vitamins for fish): Fish ≤ 2-month-old: 1 kg per 400 kg of feed or 1 kg per 6-8 tons of body weight.Fish > 2-month-old: 1 kg per 400 kg of feed or 1 kg per 10-15 tons of body weight.For pellet feed, spray the feed with the Prozyme for fish new dissolved in water (1 liter of water/6-7 kg of pellets) and leave for dry for 30 minutes before feeding
• Glusome 115 (Strengthen the body’s natural immunity system.):2g/ 1kg of feed, 2-3 times per week.

+ Avoid shocking fish, especially during seasons of change, bad weather ...

8/ Treatments:

 In reality, the farmer use antibiotics to treat bacterial infectious disease leading to unsuccess in the case export Pangasius fillet to foreign markets due to antibiotic residue. VMD is pleasue to introduce some new generation antibiotics products in order to minimize antibiotic residue issues and avoid antibiotic resistance when treating Bacillary necrosis of Pangasius disease.

• Change water in pond, after 24 hours using Vimekon 1kg/ 1.500m³ to treat water. 48 hour later, combine Vimekon 1kg/1.200 m3 or Vime Protex 1 liter/2000m³  and 50-70 kg of salt/1000 m³ to treat water and eliminate pathogen thoroughly 
• Mix antibiotic into the feed: Norflovet 20 70ml+ Cefocin New 70g or Forfish 80ml/1 ton of fish or Vime fenfish 200

Note:

- Measure the body weight of fish before using antibiotics.

- When using antibiotics to treat bacterial infectious diseases should use liver support products to strengthen ability absorption and transportation of antibiotic to fish’s body.