Photomicrograph of trichodinids impregnated with silver nitrate. Trichodina centrostrigeata (A) and Trichodina migala (B) from fish farm A; T. centrostrigeata (C) from fish farm B;
Trichodina heterodentata (D), T. centrostrigeata (E), Trichodina compacta (F), Tripartiella orthodens (G) and Paratrichodina africana (H) from fish farm C. Scale bars: 10 μm.