POST-WEANING PERFORMANCE OF SPF PIGS REARED IN ISOLATION VS. LITTER MATES REARED WITH NON-SPF PIGS

Thirty litters, comprising four pigs each, representing seven SPF herds were raised from weaning to 90 kg live weight at two locations, one a new piggery where the SPF pigs were isolated from other pigs and the other an old piggery shared with litters from non-SPF herds. Each SPF litter was represented at each location. At the conclusion of this test, data were obtained for 53 non-SPF litters tested at the two locations.The SPF pigs reared in isolation grew more rapidly and exhibited fewer health problems than those reared with non-SPF pigs. However, the differences between herds and among litters within herds were very large and in some cases the performance of pigs tested in isolation was inferior to that of their litter mates tested with non-SPF pigs. Further, the performance of non-SPF litters tested in the new location exceeded that of contemporaries tested in the old piggery by approximately the same margin as was observed in the SPF test. It was concluded that isolation from pigs of non-SPF origin was not a requisite for performance-testing of pigs from SPF herds.