| Affiliation: | (1) Department of Pathology, School of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany;(2) Centre of Life and Food Science, Institute of Animal Hygiene, Germany;(3) Institute of Physiology, Research Center for Milk and Food, Technical University of Munich, Weihenstephaner Berg 3, D-85354 Freising-Weihenstephan, Germany |
| Abstract: | Mycophenolic acid (MPA) is applied in immunosuppressive therapy after organ transplantation. As a common contaminant in silage, this substance is also frequently fed to sheep unintentionally. In this study, the effect of MPA on the immune system of sheep was examined. Four groups of 9 sheep each were fed 0, 0.5, 1.2, or 5 mg of MPA per kg body weight per day for 6 weeks. Then, the animals were slaughtered and various organs were examined macroscopically, histologically, and immunohistochemically. No effect of MPA on general health was detected. With increasing dose of MPA, germinal centres in the retropharyngeal lymph nodes displayed an activated morphology with numerous centroblasts. In the highest dose group, the sheep showed shrinkage of thymic lobules. The numbers of IgG or IgM positive plasma cells decreased in the ileum with increasing MPA-doses. These results suggest, that MPA in a high concentration may affect the morphology of immune organs of sheep. |
