Fig. 1

a Two-dimensional PLS-DA score plot representing the distribution of the samples between the first two components of the model (t1 & t2). Uninfected fish [Control (C); n = 5] are represented in red; Sparicotyle chrysophrii-infected fish are represented in different colours according to level of infection (worms fish^—1), with green indicating a high level of infection (H; n = 5), violet indicating a medium level of infection (M; n = 5) and blue indicating a low level of infection (L; n = 5). Ellipses represent the Mahalanobis distance. R2X and R2Y represent the fraction of the variance of the X and Y matrix, respectively (explained variance). Q2Y represents the predictive accuracy of the model. Values that approximate 1 indicate an effective model. RMSEE represents the square root of the mean error between the actual and the predicted responses. The model was constructed using five components (pre = 5). b Heatmap representing the abundance distribution (Z-score) of the 129 proteins identified to be driving the separation among groups in a). Dendrograms represent hierarchical clustering of proteins (rows) and samples (columns). Samples are colour coded following the same criteria as in a. PLS-DA, Partial least squares-discriminant analysis