Diseases of Fish and their Control

Disease is developed in the body of the fish by the joint activities of germs of diseases and environmental persecution. Generally diseases of fish can be developed for the following reasons-

1. Change of physical and chemical characteristics of water.
 2. Malnutrition of want of standard food.
 3. Injection by germs of diseases.
 4. Attack by parasites.
 5. Storing of more fish than the specified number.
 6. Water pollution.

When the environment of pond becomes adverse or fish is attacked by diseases  the following symptoms can be seen

1. Swimming in unusual way
 2. Floating on water and gasping
 3. Wearing off of the fins or development of scars on the skin.
 4. Come out of eyes.
5. Swelling or dropping off of scales.
 6. Development of spots on skin, fins or gills or presence of parasites.
7. Small white threading things can be seen on the body.
 8. Rottening or dropping off of wings.
9. The head being bigger in comparison with the body or swelling or squeezing off of the belly.
10. Lack of general luster of growth of the fish.

Bacterial Diseases- 

White Spot or Futki disease.

This is a bacterial disease.

Symptoms of the Disease

 Small white round spots or dots are seen on the head, dorsal side, fins. Additional slippery substance is deposited on the surface of the body. Fish moves slothfully and does not take any food. Heavily infected fish dies readily.

Prevention 

During preparation of the pond proper quantity of lime should be used.

Treatment.

1.  Potassium permanganate, at the rate of 100-150 gm per I metre, of  depth in every decimal of the pond, should be sprinkled after mixing with water on.
2.  The infected fish should be immersed for 30. minutes under 2-3% saline water of 1 minute in 5% ammonium solution and released in the pond.

Rottening of Fins and Tail

 This is a bacterial disease

Symptoms of the Disease 

Firstly white spots appear on the tail and fins of fish. The web of fins tear off. The fins and the tail decay off gradually, As a result, fish losses its balance, the colour becomes pale and ultimately dies.

Prevention 

This disease can be prevented by previously applying 1kg salt and, 1 kg lime per decimal.

Treatment 

1. The fins of the infected fish should be cut off and should be washed in 2.5% saline solution. Or
2. The infected fish should be dipped in to solution, of 0.5 gm copper sulphate in 1 litre of water, for 1 hour and released in the pond.

Dropsy or Swelling of the Belly 

This is a viral disease.

Symptoms of the Disease

 Some liquid substances deposited in one or more than one organ of the body of the fish. The scales become loose and swell. Water come out through the rectum if the belly, if pressed. Majority of the infected fish die.

Prevention

 During preparation of the pond 1 kg lime per decimal may be applied.

Treatment 

1. Fish infected by this disease can not be cured. At the initial stage, application of potassium permanganate at the rate of 2 gm per cubic metre of water of the pond gives good result.
2. Terramycin should be mixed with food the rate of 100 mg per 1 kg of food and this should be fed for 7 days.

Fungal Disease

 Gill Rot Disease

 This is a fungal disease. One type of fungus enters into the gills of fish and stops blood circulation. As a result, the supply of food and oxygen to the Diseases of Fish and their control external part of the gill the stopped.

Prevention

 1. Deposition of excessive organic matter in the pond should not be allowed.

2. Lime should the applied at proper dose previously.

Treatment

 Generally the fish infected by this disease dies. At the initial stage, the infected fish should be dipped in to a solution, of 5 mg. copper sulphate in one litre of water for 5 minutes and released in the pond, good result can be expected from. 

Treatment Generally the fish

 infected by this disease dies. At the initial stage, the infected fish should be dipped in to a solution, of 5 mg. copper sulphate in one litre of water for 5 minutes and released in the pond, good result can be expected from. 

Symptoms of the Parasites 

Sores develop or, the body of the fish. Fungi and bacteria infect the sores. Infected fish moves with unnatural swift speed and begin to rub its body with hard things. 

Prevention

 The environment of the pond should be kept clean and pollution free. 

Treatment. 

1. For every decimal of the pond 40 mg. dipterex should be applied for I metre depth. This should be applied twice in an interval of 7 days. Or 

2. The infected fish may be dipped into 15-20 PPM formalin solutions and then released in the pond. 

Virus Caused Disease
 Fish Necrotic Disease or Sore Disease.

 This disease is created at the primary stage by the viral infection and laterally by fungal or bacterial infection. It is a contagious disease. This disease develops in the adverse environment of the pond.

Symptoms of the Disease 

Firstly spots can be seen on the body of the fish. Scales of the infected part drop off. The red spots gradually turn into big sore. The fish floats on the water slothfully an swims very slowly. The infected fish dies within 10-15 days. 

Prevention

 The severity of this disease can be minimised by application of proper dose of lime during preparation of the pond. 

Treatment

 1. 1 kg. lime and 1 kg salt per decimal of pond will have to be applied in the infected pond. 

2. The infected fish should be dipped into 5PPM malakhite solution for 15 minutes and then released in released in the pond.

Malnutrition Diseases

 When a special type of mark or symptom develops on the body of the fish for want of a particular food nutrient then it is called diseases due to malnutrition. In case of fish shortage of protein and vitamin can be noticed vigorously. 

Symptoms

 The growth of fish is greatly related for want of protein. As a result, the head become big in comparison to its body, some parts of the body of the fish may be curved or crippled due to shortage of vitamins. The infected fish gradually dies. 

Treatment

 The fish should be fed protein, vitamin, mineral slat mixing in proper proportion with the supplementary food.