Parasitic Diseases in fishes

1. Parasitic Diseases in fishes By Dr. Mohamed Sayed Mohamed Marzouk Professor of Fish Diseases and Management , Faculty of Veterinary Medicine, Cairo University

2. Parasitic Diseases of cultured fishes What is meant by Parasite ? ً Classification of different parasites • Protozoa (unicellular). • Helminthes (multi-cellular) • Crustaceans

3. Protozoa • Accordingtohabitate: • External. • Internal (Blood and Tissue). • Accordingtoshape: • Cilliates (Icthyophthirius, Chilodonella, Trichodina). • Flagellates (Ichthyopoda, Trypanosoma, Cryptobia, Hexamita). • Sporozoa (Myxosoma).

4. External protozoa 1. Exteranl cilliated protozoa: • Ichthyophthiriusmultifillis • Chilodonella spp. • Trichodina spp.

5. 2. Exteranl flagellated protozoa: • Ichthyoboda (Costia) necatrix and pyriformis • Piscinoodinium spp. • Amyloodinium spp. • Cryptobia spp. 3. Internal flagellated protozoa • Hexamita spp. • Trypanoplasma spp.

6. Ichthyophthiriummultifilistrophozoit (Stained )

7. Ichthyophonusmultifillis (unstained)

8. Stained Trichodina from skin mucus scraping

10. Pathogenesis of external protozoa Protozoal invasion Skin cellular irritation 1. Abnormal swimming 2. Excessive mucus Skin cellular destruction 1. Haemorrhages 3. C.T capsules (White spots). 2. Erosions and ulcers

11. Life cycle of Ichthyophthiriosis

12. Clinical signs • Abnormal swimming(Flashing, circling, sluggish and itching ). • Surfacing and gasping (Asphyxia). • Excessive skin mucus ( patchy then generalized ). • Pathognomonic white spots (Ichthyophthiriosis), Yellow • shine or Rust (Oodiniosis). • Skin haemorrhages, erosions and ulcerations. • Emaciation and death.

13. White spot disease

14. Cryptocarion irritans infection in marine fish

15. Surfacing and gasping in gill infection

16. Diagnosis of External parasitic Diseases 1. History ( new introduced fish, water parameters,……… 2. Clinical signs and lesions. • 3. Demonstration and identification of the causative parasites • Skin and gill mucus scraping (wet mount). • Stained skin and gill mucus smears.

17. Treatment of External parasitic Fish Diseases • External chemical treatment • Dip treatment • Bath treatment • Flush treatment • Indefinite bath treatment • Non-chemical treatment • Increase water temperature in White Spot disease • Change water facility • Use of ultraviolet radiation in re-circulating system

18. Types of Chemical treatments 1. Disinfectants: • Pot. Permenganate. • Malachite green. • Formaline. • Na Cl. • Acriflavin. • Methylene blue.

19. 2. Pesticides: • Chlorinated Hydrocarbones. • Organophosphates.

20. Control of Fish diseases in infected fish farms • In infected earthen ponds: • Drainage • Dryness • Disinfection using quick lime • In infected concrete or fiberglass fish tanks: • Drainage • Disinfection with strong antiseptics

21. Hexamitiosis • Systemic infection caused by an internal flagellated protozoa Causative protozoa Hexamita truttae Hexamita salmonis Hexamita intestinalis

22. Mode of infection and transmission: 1. Infection through ingestion. 2. Transmission is from dead fish and contaminated water body. Pathogenesis Hexamita is normal inhabitant of intestine Large numbers Small numbers Systemic form Intestinal destruction No signs Intestinal irritation Hole in head Excess mucus Off food & emaciation

23. Clinical signs: 1. Off food. 2. Emaciation and tucked up abdomen. 3. Mucus shreds from the vent. 4. High mortality in severe cases. 5. Hole in the head in systemic form (Fistula behind the head exuding white material).

24. Diagnosis Clinical signs and lesions (Non-confirmative) Laboratory ( Confirmative) Sampling ( Intestinal mucus ) Quantitative (Count/ MF) Qualitative 0 - 5 = Negative 5 – 15 = Mild 15 -30 = Moderate 30 – 100 = Severe More than 100 = Marked

25. Treatment and control 2. Hexamiticides 1. Expulsion Sulfonamides Saline purgative (MgSO4) • Aresenical (Carbersone). • Murcurial (Calomel). Can be used in food fishes Not to be used in food fishes

26. Fish Helminthosis • Helminthes infection or infestation? Helminthes of fishes Platy helminthes Round worms Trematodes Cestodes Larvae A dults

27. Fish Trematodes 1. Monogenea 2. Digeanea Adults Gill flukes Skin flukes Encysted metacercaria

28. Gillflukes 1. Dactylogyridae 2. Cichlidogyridae Cichilidogyrus tilapiae (C. tilapiae) Dactylogyrus vastator (D. vastator)

29. D. vastator

30. C. tilapiae

32. G. elegans

34. Haemorrhagic granuloma of Lernea copepode

35. 2 egg sacs Anchor Lernea cyprinicae

37. Fish lice ( Argulus sp.) attached to fish skin

38. Ventral view of Fish Lice

39. Thank You