TLR4 and endometritis: For example, knockout of TLR4 could suppress the pro‐inflammatory state of diabetes in mice.51 TLR4 knockout mice have neuroprotective effects against ischaemia/reperfusion‐induced brain injury.52 Moreover, previous studies have also reported that the expression of TLR4 in the endometrium of postpartum cattle that develop endometritis and infertility was apparently higher than that of normal cattle.53 Based on these findings, we suspected that reduction of TLR4 expression could attenuate the inflammatory condition of endometritis.