Fish Diseases

1. Topic: Diseases of Fish
Dr. Ramkumar Lodhi
Conservation Biology Lab

2. synopsis
Introduction.
Dropsy.
Tail Rot or Fin Rot.
Eye diseases.
Furunculoris.
Costiasis.
White spot (Itch).
Fungal diseases.
Swimming bladder diseases.
Conclusion.
Reference.

3. INTRODUCTION
Large no of diseases occurs in all aquatic animals including fish.Due to
nutritional deficiency or unhygienic condition of water or attack of
parasites.
All species of fishes becomes infested with pathogenic bacteria.
A sick fish generally is unable to maintain balance in the water,usually
lie on the side either at the bottom are floating at the surface.
The gills becomes pale,body covered with grey slime and there is
normal colour.
A sick fish is sluggish skinness of the fish in the pond may be due to
the change in the physico – chemical of water and due to shortage of
food.

4. DROPSY
 In this diseases there is accumulation of fluid in the internal
organs causing swellings.Intestine,liver and kidney are
badely effected.
 It is caused by bacteria called psedomonas puntata and
Aeromonas hydrophilla.
 Most fishes with this problem can survive only 2-3 weeks
but sometimes as many months.
 Dropsy is mainly found in carps like Catla and Rohu.
Control measure
 Dropsy is mainly treated with chloralphenicol antibiotics
added in water. The fishes kept in the solution for 3-7 days.

6. TAIL ROT OR FIN ROT
 Tail rot is basically erosion and disintegration of fin and tail.
 In earlier stage white line appears on fin which may leads to fin lost.
 Tail rot is caused by Pseudomonas Floresence.
 It occurs due to poor quality of water.
 If fin rot is noticed in the early stages and treated then fish may be
survive. If tail rot remains untreated then entire tail is lost and fish
die.
 Control measures
 The diseases may be cured by dipping in the copper sulphate
solution for 1-2.
 If heavy infection,the affected portion of tail should be removed and
then wash by 1% silvar nitrate.
 The fish kept in a diluted sol of potassium dichoromate for healing of
wounds which may require 7-10 days

8. EYE DISEASE
 This disease is caused by bacteria streptoccus iniae, as well
as Lactococcus,entrococ-cusrococcus.
 The most common symptom of these bacteria will show as
cloudy eye and bulges outwards from eye cavity ,thus
called pop eye diseases.
 The conory becomes vascularised leading to opacity eye
becomes whitish and loss of balanace in the body of fish.
 It is observed in Rohu catla and silvar fish.
 Control measures
 The diseased fish may be treated by chloromycetin in the
early stage of this diseases,then fish kept in 1% of KMnO4
for 3 minutes

10. FURUNCULOSIS
 Mostly observed in salmon,trout and goldfish.
 It is caused by bacteria Aeromonas salmonicida.
 The infected fish develops swellings on the sides of the
body which may leads to ulcer.
 The swelling contains pus like substance formed by
necrosis of muscle cells.
 Control measure
 Cured by antibiotics oxytetracycline and sulfamerazine.

12.  This disease is caused by ectoparasite costia which is a flagellate that
attacks skin and gills, destroys epidermal cells and feed them.
 As a result excessive secretion of mucus.
 The body of the fish becomes covered with bluish or grey film of
mucus.
 Loss of appetite, and becomes weak and dies after sometime.
 Another protozoan ciliate chilodon also attacks skin and gills.
 Control Measures
 Both the protozoan are controlled by treating the fish with 1% acetic
acid solution or solution of formalin.
 Solutions of methylene blue, KMnO4, CuSO4 can also be used to kill
the parasite.
COSTIASIS

14. WHITE SPOT
 This disease caused by ciliated protozoan Ichthyophthirius species.
 The parasite attacks the skin of fresh water fish, rest in between epidermis and
dermis .
 Infection results in the appearance of several white spots on the skin
and fin due to rapid proliferation of epidermal cells ,which forms a covering
over the parasite.
 The entire body of the fish are covered by nodules trophonts.
CONTROL MEASURES
 The fish kept in the 3% salt solution or 1% solution of formaline and then
methylene (2 minutes).
 The parasite also killed by rising up the temperature above 24 degree celicious.

16. FUNGAL DISEASE
 The fungal disease is mainly caused by seprolegnia and are
characterised by the appearance of wool (tufts) on the skin.
 Root like hyphae or filaments grows in to the subcutaneous parts,
causing death of the fish.
 Gills are also affected causing gill rot .Gill first becomes pale then latter
yellow-brown and destroyed.
 The infection spread quickly when the fish is already injured and
weak.Healthy eggs also affected if dead eggs are not removed from the
water.
CONTOL MEASURE
 The fish is taken out from the water and the affected part washed with
iodine solution,then the fish kept under 1% potassium dichromate for a
week.
 We could also kept the fish under 3% solution of salt as well as 1%
solution of phenoxethol also kills the fungi.

18. SWIM BLADDER DISEASE
 Swim bladder disease refers to a condition when the
swim bladder donot work normally due to diseases
or environmental factors.
 Affected fish will exhibit problems with buoyancy
that is ,they will have difficulty controlling their
ability to flout or sink.
 Fish have swollen belly, mainly observed in gold fish.
 Affected fish may eat normally or have no appetite at
all.This disorder is some times caused by
compression of swim bladder,which may involve a
distended stomach from rapid eating or overeating
or gulping air.

19. CON….
 Gestrointestinal tract enlargement puts pressure on the swim
bladder or other abdominal may enlarge and affect the swim
blader (kidney and liver)
 Due to swim bladder disease, fishes don’t maintain normal
position in the water.
CONTROL MEASURE
 If the fishes have SBD, the first course of action is not to feed
fish for three days.At the same increasing water
temperature(80 degree celicious).
 Adding small amount of salt in the tank.Reducing the water
level to make it easier for fish movement around the
tank.Hand feeding is necessary.

21. CONCLUSION
 The disease is harmful for both wild and cultured
fishes of our country.
 Disease in fishes may cause a heavy loss for
commercially cultured fishes. So we should be
know about the signs and symptoms of disease,
that we can easily find out the proper treatment .
 Fisheries is an important tool of self-employment
because fish is an important source of nutrients
and have have great economic value.

22. REFERENCE
• S.S. KHANA and H R SING. Fish biology and
fisheries.
• Biology of fishs ;3rd edition by RICHARD
MOORE AND QUENTIN BONE.