On the other hand, there were higher concentrations of IL-8, IL-1β and IL-1α in the vaginal mucus collected 3 weeks postpartum from 13 animals that had dystocia compared with animals that had normal parturition, and the concentrations of IL-1α remained higher in the vaginal mucus of dystocia animals sampled 5 weeks postpartum (Fig. 1b–d). This evidence concerns the gene CXCL8 and dystocia.