Initial levels of maternally derived antibodies predict persistence time in offspring circulation

Vertebrate mothers transmit antibodies to offspring that provide humoral immunity early in life. The duration of protection provided by maternal antibodies varies considerably among species and has not been widely examined in birds. Determination of the length of maternal protection can be a useful predictor of when young are most likely to be susceptible to infection. The duration of maternal antibody protection was determined in Japanese Quail (Coturnix japonica) by immunizing females with keyhole limpet hemocyanin (KLH) and then collecting blood samples from offspring. Maternal antibodies remained detectable in offspring circulation for an average of 14 days (range 3-28). The duration of persistence was predicted by antibody levels as measured in maternal circulation, within egg yolks, or measured in offspring shortly after hatch. Thus, the primary benefit to offspring of high concentrations of maternal antibodies is likely to be an extended period of maternal protection during early growth and development.