Comparison of body weights, organ weights and histological features of selected organs of gnotobiotic, conventional and isolator-reared contaminated pigs.

Twenty-seven pigs from three litters were used in a comparison of body weights, organ weights, and selected histological features of germfree, conventional and isolator-reared contaminated pigs. At three weeks of age conventional pigs were heavier than pigs of the other two groups. The mandibular lymphnodes, stomachs, and small intestines of contaminated pigs were significantly heavier than the same organs of germfree pigs. This difference was not found in superficial inguinal or prefemoral lymph nodes. Other statistically significant organ weight differences were found.Histologically, the lymph nodes of conventional and contaminated pigs were much more active than those of germfree pigs, although secondary nodules were occasionally found in lymph nodes of germfree pigs. Greater quantities of iron-containing pigment were found in the spleens of germfree pigs than in spleens of the other two groups. Hepatic interlobular septa were somewhat more developed in conventional pigs than in germfree or contaminated pigs.