Fig. 1

Score plots of multivariate statistical analysis. a Principal component analysis (PCA) score plots for all samples. Case 1 Cryptosporidium baileyi-infected chickens, Con 1 phosphate buffer saline-inoculated chickens, QC quality control. b Partial least squares-discriminant analysis (PLS-DA) score plots for Case 1 and Con 1 samples, c orthogonal partial least squares-discriminant analysis (OPLS-DA) score plots for Case 1 and Con 1 samples, d results of 200-times response permutation testing of OPLS-DA. Q2 and R2 represent the intercepts of the regression curve and y-axis generated by the linear regression between the R2 and Q2 values of "permuted” model and the R2Y and Q2Y values of the "real" OPLS-DA model, respectively