This document discusses Trichodina, a ciliated protozoan parasite that infects fish. It belongs to the phylum Ciliophora. Trichodina has a dorsoventrally flattened oval shape and lives on the skin, gills, and sometimes urogenital system of fish. Infection is more common under conditions of poor water quality, high bacterial counts, stress, and high temperatures. Clinical signs include excess mucus, skin reddening, and lethargy. Prevention focuses on water quality improvement and treatment includes chemical baths.

1. JANASHRIT SHRESTHA
ROLL NO.- 21

2. INTRODUCTION
Protozoal disease caused by ciliate protozoan
Trichodina spp.
Scientific Classification
Phylum-Ciliophora
Sub-phylum-Intramacronucleata
Class-Oligohymenophorea
Subclass-Peritrichia
Order-Mobilida
Family-Trichodinidae
Genus-Trichodina

3. Genera
Trichodina
Paratrichodina
Trichodonella
Tripartiella
Vauchomia

4.  Dorsoventrally flattened oval ciliated protozoa of
marine and freshwater species of fish
 Side view-Saucer shaped
 Distinctive character of this protozoa –Presence of
prominent denticular ring
 Lives on mulm of substrate;fish body somewhat acts
as substratum
 Feed upon suspended particles in water,bacteria and
dead skin cells of fish

7.  Found on skin and gills and sometimes on urogenital
system
 Infection depends upon
 Protozoal load
Adverse climatic conditions
Fish under stress
Reproduce by simple binary fission

8. Poor Quality water
High Bacterial count
Source of food for protozoa
Leads to high number of protozoa

9. Seasonal Dynamics and Body size
High temperature of water in summer (29°C)
prevent proliferation of Trichodinids
High prevalance in spring (18°C)
Young fish and fry more susceptible than
mature fishes

10. Factors Affecting Trichodiniasis
 High stocking density -Spread fast and lower
production
Generous feeding rate –Leads to high ammonia
concentration creating ideal environment for
reproduction of Trichodina

11. Clinical Presentation…
Affected fish produce excess mucus and develop white
cast to skin
Focal areas of reddening
Lays near substrate to rub against surface
Lethargic
Often gill swelling

14. HISTOPATHOLOGY
 Host response to ciliate infection is an inflammatory
response
Disrupt first line defense in skin and gills
Results in
 Hyperplasia of epithelial cells of skin
Clubbing of gill filaments
Massive manifestation leads to superficial to deep
ulceration allowing putative route for secondary and
fungal infection

15. Prevention…
Decrease stocking density
Decrease organic debris
Maintain Quality of water
Installation of heating system

16. Treatment ..
• Mixture solution of CuSo4 and FeSo4(5:2)
dispersed over evenly whole affected pond.
• Disinfect the fingerlings with 9 ppm Cuso4 soln
for 20-30 min 0r with 1-2% aqueous soln of table
salt for 2-10 min.
• Formalin at concentration of 30 ppm can kill
trichodina however affects the water quality and
fish appetite.

17. THANK YOU……….