Kinetics of immune response and pathological changes in trout olfactory organ following Ich parasites infection.

(A) Heat map illustrates results from quantitative real-time PCR of mRNAs for selected immune markers in parasite-challenged versus control fish measured at 1, 7, 14, 21, 28 and 75 days post infections with Ich parasite in the olfactory organ of rainbow trout (n = 6 fish per group). Color value: log2 (fold change). (B) Relative expression of IgM, IgD and IgT at 1, 7, 28 and 75 days post infection with Ich parasite in olfactory organ of rainbow trout (n = 6 fish per group). (C) Histological examination (haematoxylin & eosin stain; H & E) of the olfactory organ from ich-infected rainbow trout 7, 28, 75 d.p.i and uninfected fish (n = 6 fish per group). Black arrows indicate the width of LP at the tip region (100 μm from the lamellar tip) of the olfactory lammella and red arrows indicate goblet cells. (D) The width of LP at the tip region the olfactory lamella in ich-infected rainbow trout 7, 28, 75 d.p.i and control fish counted from C. (E) The number of goblet cells at the olfactory lamella in ich-infected rainbow trout 7, 28, 75 d.p.i and control fish counted from C. *P P P < 0.001 (one–way ANOVA with Bonferroni correction). Data are representative of at least three independent experiments (mean and s.e.m.). Anova, analysis of variance.