2. Materials and methods
2.1. Experimental design
Caesarian-derived colostrum-deprived (CDCD) Land-race and Large White cross-bred pigs were obtained from a contract facility when they were approximately 5 weeks old for all but the M. hyosynoviae challenge studies. For the separate M. hyosynoviae study, the pigs were received at about 12 weeks of age. All pigs were acclimated for 1 week prior to being assigned to study groups and challenged. All animals were randomly assigned per treatment using the ear tag number initially assigned to all animals. Parental and litter effects were not taken into consideration for randomization. The pigs were housed under strict biocontainment conditions at the Iowa State University animal research facilities.