In vivo expression profile and stability of Bsal candidate reference genes. Shown is (a) the variation in the mRNA expression (Cq) of GAPDH, TUB, R6046 and α-centractin in skin (chin, belly and tail) tissue of experimentally Bsal-infected fire salamanders (n = 3). The whiskers represent the median, the minimum and maximum values, and the first and third quartiles. A plus (+) indicates the mean Cq value. (b) At euthanasia, different fungal loads were detected in the skin tissues. (c) GeNorm stability analysis providing a GeNorm M and coefficient of variation (CV) value. (d) BS_08640 and BS_08614 mean fold change in mRNA expression profiles. The data shows the normalized target gene quantities in skin tissue from Bsal-infected Salamandra salamandra, relative to freshly collected spores which is considered 1. The results are presented as means + SEM with significant differences shown by the P value.