[Natural resistance and immunological reactivity in pigs weaned at various ages]

Studies were carried out on the changes in some indices of the natural resistance and immunologic response (total protein, monoamino-oxidase, and lysozyme, antibacterial, and phagocytic activity, and erythrocyte-rosette forming cells and antibody activity) of the blood of pigs that were weaned and vaccinated at 42, 28, and 18 days. The dynamic of these indices in the process of weaning and vaccination as well as in a 3-week period pointed to certain advantages with pigs weaned at more advanced age.