Differential expression of eleven genes (IL6, IL8, CD14, TLR4, IL1B, LBP, TLR2, C5AR1, TNF, IFNG and SAA3) during mastitis was confirmed in more than one (two to four) expression experiment, moreover, six genes (IL6, CD14, TLR4, IL1B, TLR2 and SAA3) were found to be differentially expressed in two species (cattle and mouse). This evidence concerns the gene IL1B and mastitis.