During weaning, piglets are under strain from the loss of their dam, the change in feed, and a new microbiological environment. How much this strain influences the piglets depends mostly on their immune system. Piglets from organic production are weaned later (at least 40 days) than piglets from conventional rearing, but the performance and health status of organic piglets are often not satisfying. Therefore, it was the aim to investigate whether a prolonged suckling period of 63 days results in better immune status of piglets than with weaning at day 42. To answer that question we vaccinated piglets at different times with a “known” (by vaccination of dam) and an “unknown” antigen and analysed the plasma for immunoglobulin G (IgG) concentration and the antigen-specific IgG antibodies by ELISA. Two farrowing cycles of 36 sows were recorded. Time of vaccination did not influence IgG concentration. In contrast, early weaned piglets showed a higher IgG concentration on day 49 than late weaned piglets. During the first farrowing cycle a significant immune response against both antigens was present in piglets vaccinated on day 42. Such a response was not found in piglets vaccinated on day 63 and in piglets of the second farrowing cycle. In conclusion, the results did not show an improved immune status of piglets undergoing a suckling period of 63 days
