Possibilities of overcoming the inhibitory effect of colostrum-derived antibodies using intradermal immunization and immunization via mucosae

The colostrum-derived antibodies protect piglets in early life. Levels of these antibodies gradually decrease in sera of growing piglets and according to the prevailing opinion they decline so much at a certain time point that they cannot protect the organism against infection and even block the onset of active immunity. This period has been generally designated as the “immunity window” (1). On the other hand, our previous studies and studies of other authors (1-3) indicated that co