Immunotoxicological effects on piglets of feeding sows diets containing aflatoxins

Three groups of four Large White sows were fed diets containing either 800 ppb purified aflatoxin B1 (group 1), 800 ppb purified aflatoxin G1 (group 2) or 400 ppb B1 and 400 ppb G1 (group 3) throughout gestation and lactation. A control group of four sows was fed a diet free of aflatoxins. Aflatoxins B1 and M1 were found in milk samples taken five and 25 days after parturition from the sows of group 1, aflatoxin G1 was present in the milk of the sows of group 2 and all three aflatoxins were present in samples from the sows of group 3. The concentration of aflatoxin in the milk was about 1000-fold lower than that in the feed, but increased over the 25 days after parturition. The piglet suckling on a central teat was selected from each sow, given sow milk until the fourth day of age, and was then free to eat prepared feed while suckling. At the 25th day of age the selected piglets were removed from the sow and sacrificed. Blood samples were collected from each piglet and cellular populations were separated for immunological measurements: an in vitro lymphocyte proliferation test, and tests to derive the phagocytic activity, phagocytic index and superoxide anion production of monocyte-derived macrophages were carried out along with studies on the motility, differential chemotaxis and chemotactic index of circulating granulocytes. The lymphoproliferative response to mitogens was reduced and monocyte-derived macrophages failed to efficiently produce superoxide anions after oxidative burst stimulation in vitro, while their ability to phagocytose red blood cells was not compromised. Granulocytic cells showed a reduction of chemotactic response in vitro to chemoattractant bacteria factor and casein.