A. Causes: Flavobacterium columnare or Fexibacterium columnare
B. Characteristics of pathogens:
- This bacterium is in the form of gram negative bacteria, the shape of the rod is small, moves by sliding, is found and lives in fresh water.
- This bacteria has a group of snails forming a group like column.
- Bacterial infections in fish are generally associated with stress conditions due to: changes in extreme water temperature and poor water quality in the pond.
Bacterial attacks often occur in groups of fish after transportation.
C. Clinical symptoms:
- there is a wound around the mouth, head, body or fish fins. Brownish white lesions then develop into ulcers.
- Infection around the mouth of the fish, the infection looks like it is wrapped in thread (thread-like)
so that it is often referred to as the "mouth fungus" disease.
- Around the affected wound is covered with bright yellow pigment.
- When infecting the gills of a fish, there will be damage that starts from the end of the gill filament and propagates to the base, finally filament decays and falls (gillrot).
- by observing preparations of drops hanging in a microscopic (400x) way to see the presence of bacterial columns in the target organ of infection.
- Isolation and identification through bio-chemical tests.
- Means of cultivation used are disinfected before and during the process of raising fish in the pond;
- Carrying out immunostimulant elements by adding vitamin C to feed regularly during the maintenance of fish in the pond;
- Avoiding stress on fish (physical, chemical, biological);
- soaking with 0.5% kitchen salt or 5 mg potassium permanganate for 1 day;
- Improving the quality of pond water as a whole, especially reducing the levels of dissolved organic matter and / or increasing the frequency of new water replacements;
- Perform integrated fish health management (fish, environment and pathogens).
- Benzalkoniumchloride at a dose of 18-20 mg / liter through soaking for 2-3 days
- Fish that are sick can be treated with herbs using plants:
1. Rhubarb (Rheum officinale L.)
treatment is done by counting 1 kg of rhubarb leaves until smooth and then mixed into 20 liters of water, use the water to soak the sick fish within 6-12 hours. Or it could be by chopping 20 kg of leaves, then mixing it into 20 liters of water to spread to the cultivation pond with a pool area of 1/5 ha.
2. Antingan (Acalypha indica L.)
Treatment methods are 125-500 g of chopped dried leaves or 2 kg of fresh leaves and then mixed with the chopped plants into fish feed for 100 kg of fish by giving 3 times a day for 3 days.