Summary Parasites of freshwater fish

Parasites of freshwater fish

Protozoa

Ciliates

- Site of infection is usually the intestine, gills, skin and fins

- Symptoms include skin and gill irritation, white spot, excessive mucus secretion in gill,
enlarged eye

- Taxa: Ichthyopthirius, Chilodonella, Tetrahymena, Trichodina, Epistylis




Flagellates

- Parasites of the intestine, stomach, skin, gills and fins

- Main symptom is mucous secretion

- Taxa: Hexamita, Ichthyobodo, Piscinoodinum, Cryptobia




Microsporideans

- Infect the swim bladder, kidneys, viscera, and form cysts in lymph

- Symptoms include hypertrophy of tissues, thickening of kidney walls and formation of
tumour-like masses in the tissues

- Taxa: Plestophora, Enterocytozoans, Glugea




Myxozoans

- Indicative features are cysts in muscles, connective tissues, epithelial lining of bladder,
kidney tubules and gut lining

- Infection causes hypertrophy of cells, and formation of tumour-like masses in tissue

- Taxa: Myxozoma, Mitraspora, Thelohanellus, Myxobolus