Detection of Interleukin-1β in Sera and Colostrum of Dairy Cattle and in Sera of Neonates

Abstract

In order to obtain basic information about bovine interleukin-1 (IL-1β), levels of IL-1β in sera and milk of clinically normal mature Holstein cattle before and after parturition and in sera of newborn calves were examined by ELISA. The level of IL-1β was undetectable in sera of mature cattle around the time of artificial insemination, but the concentration gradually increased and reached a peak at parturition and then decreased again to an undetectable level. IL-1 β in milk was detected on the day of parturition but not thereafter. IL-1β mRNA was detected by reverse transcription-polymerase chain reaction in the cells from milk collected during 20 days before and 2 to 3 days after parturition, but was not detected thereafter. Although IL-1β was not detected in all the sera of newborn calves, the concentration transiently increased with peak titers on day 3 and became undetectable by day 14 after birth. Newborns that showed serum IL-1β on day 3 had been fed on colostrum in which the IL-1β concentration was significantly higher than that in colostrum that had been fed to newborns having no detectable IL-1β on day 3. These results indicate that IL-1β is induced in association with pregnancy in healthy dairy cattle and that the cytokine might be transferred to neonates via colostrum.