| Endoparasites | Protozoa | |
| • Eimeria spp. | Small intestine |
| • Histomonas meleagridis | Caeca, liver |
| Nematodes | |
| • Oxyspirura mansoni | Eye, lacrimal duct |
| • Syngamus trachea | Trachea, lungs |
| • Gongylonema ingluvicola | Oesophagus, crop |
| • Tetrameres spp. | Proventriculus |
| • Acuaria hamulosa | Gizzard |
| • Capillaria spp. | Entire intestine |
| • Dispharynx nasuta | Erythrocytes, proventriculus |
| • Amidostomum anseris | Gizzard |
| • Ascaridia galli | Small intestine, occasionally oviduct |
| Cestodes | |
| • Raillietina spp. | Small intestine |
| | |
| Ectoparasites | The fowl tick | |
| • Argas persicus | Skin |
| Mites | |
| • Dermanyssus gallinae | Skin |
| • Ornithonyssus sylviarum | Skin |
| • Cnemidocoptes mutans | Skin on legs, comb and wattle |
| Flea | |
| • Echidnophaga gallinacea | Head |
| Haemoparasites | • Leucocytozoon spp. | Leucocytes, erythrocytes |
| • Plasmodium spp. | Erythrocytes |
| • Haemoproteus spp. | Erythrocytes |
| • Aegyptinella spp. | Erythrocytes |