2. Protozoan Diseases in Fish:
● Costiasis
● Whirling
● Trypanosoma
● White spot
● Trichodiniasis
3. Costiasis Disease in Fish:
● This is caused by a mastigophore - Costia necatrix in culture fishes.
● This is a common disease in ponds where fishes live densely in water with a low
pH and poor condition food.
● The parasites live in large numbers on fish skin, fins and gills. The symptoms are
appearance of grey blue film on the skin which turns to red patches in severely
affected cases.
● The infected fish becomes weak; loss of appetite occurs and finally dies.
● They can be treated with 3% common salt for 10 minute or 1: 2500 formalin
solution.
5. Whirling Disease in Fish:
● This disease is caused by a myxosporidian protozoan, Myxosoma cerebralis only in salmon fishes.
● The symptoms are pancreatic necrosis, lesions and disintegration of the cartilaginous skeletal
support of the organ of equilibrium.
● Rapid tail-chasing type of whirling is often seen when the fish is frightened or trying to feed.
● The typical symptoms usually appear at 1-2 months after exposure to the disease.
● If the pond contains all infected fish, it is better to destroy them by deep burial. Then the pond
should be cleaned thoroughly and disinfected with calcium cyanamide, quick lime or sodium
hypochlorite.
6. Trypanosoma in Fish:
● Trypanosomes are ubiquitous blood parasites of marine and
freshwater fishes, typically transmitted by aquatic leeches.
● Phylogenetic studies have been dominated by examples derived
from freshwater fishes, with few marine representatives.
7.
8. White Spot in Fish:
● White spot is a contagious parasitic disease of fish. Caused by
Ichyophthirius multifilis, the parasite infects the fish after moving from the
bottom of the pond. The parasite attaches itself to the fish, moving under
the skin where it feeds on cells and body fluids.
● Later in the parasite's life cycle, it moves out of the fish and attaches itself to
pond material where it repeatedly divides itself thousands of times. These
then hatch and the process begins again.
●
● The parasite causes damage to fish tissue which can lead to bacterial and
fungal infections.
9. White Spot in Fish:
Where and when might it occur?
● The disease can affect most fish species but is most common in carps.
● The parasites are often introduced through infected fish or pond equipment.
● Changes in environmental conditions such as the introduction of lower
temperature water to that of the pond or tank can also cause the release.
10. White Spot in Fish:
Diagnosing white spot disease:
● The illness is first detected through behavioural changes in the fish. Fish will
often be seen to rub themselves against stones as the parasite enters the
skin.
● Disorientated swimming close to the surface or staying close to the bottom
and tightly folded fins are also observed.
● In the later stages, small white cysts will start to appear over the fish,
including the gills. These are roughly the size of a grain of salt.
11. White Spot in Fish:
Control and Treatment:
● To stop the parasites from being released, zinc-free malachite is used in the
pond (0.1ppm). Instructions on use must be followed carefully to prevent
toxicity.
● To prevent the disease it is advised to quarantine new fish for two weeks
before introduction.
13. Trichdina in Fish:
What causes Trichodina?
● Trichodina is one of the parasites that you can't see without a microscope. This parasite
is usually found on the gills, skin or fins of the goldfish. It's important to know that
Trichodina doesn't feed on the goldfish, it only uses them as home and transportation.
● Usually, healthy fish can control the number of parasites, but in severe conditions and in
large numbers, Trichodina can run down your goldfish's immunity system and open a
door for other complications such as ulcers or other secondary bacterial infections.
● Severe Trichodina infestations are caused by poor water quality and overcrowding. They
feed of the bacteria on the fish's surface and cause rapidly multiply as they reproduce by
binary fission(each cell splits into two).
14. Trichdina in Fish:
What are the symptoms?
● scratching and flashing
● ulcers
● stop feeding
● fish may isolate themselves
● lay at the bottom with clamped fins
● lethargic
● irritated skin
● greyish, white film over the body of the fish in severe cases
15. Trichodina in Fish:
How to cure Trichodina?
● The best treatment is using the same medications as you use to kill Ich. You can
use the salt treatment or medicated treatments like potassium
permanganate(works almost every time) or Malachite Green with Formalin or use
Proform C(colder water temperature) or QuickCure(in warm water temperature).
How to prevent Trichodina?
● Quarantining and treating any new goldfish is the key to preventing any infestation
of any parasite. Also remember to keep a high quality water, do not overcrowd your
tank and feed your fish healthy, tasty, fresh food.
