Impact of O. ostertagi ESP on the transcription of inflammatory factors in bovine epithelial cells. Relative expression levels of IL1B, IL8, TNFA and COX-2 were quantified in cultured bovine mucous epithelial cells following preincubation for 24 h with O. ostertagi adult and L4 ESP at different concentrations. In addition, cells were treated with 8 ug/mL LPS corresponding to the highest concentration of LPS contamination present in the ESP. Relative expression levels were normalized against RSP 29 and expressed as mean fold change ± SE. (*p value ≤ 0.05).