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第17号公告板 - Winter 2003
VirologyPorcine Reproductive and Respiratory Syndrome (PRRS)
BATISTA L, DEE S, OLIN M, MOLITOR T, XIAO Z, MURTAUGH MP, JOO HS, PIJOAN C
Immunological features of porcine reproductive and respiratory syndrome (PRRSV) against homologous and heterologous challenge in a population of breeding age female swine.
Allen D. Leman Swine Conference 2003: 55-59
BO98441
Humoral and cellular immune responses were assessed in both na?ve and previously PRRSV-challenged gilts when re-challenged with different strains of PRRSV. On day 0, all gilts were inoculated with a field isolate. On day 120 they were allocated into 6 different groups: in group 1 animals were not subjected to further challenge, in group 2 animals were re-challenged with the same isolate (homologous group), whereas in each of the other 4 groups animals were re-challenged with a different isolate presenting a sequence heterology of 3.4%, 5.4%, 16.5% and 11.3% respectively with the first isolate (heterologous groups). Heterologous groups showed viremia on day 3pi but not later on. Fever, anorexia and depression were present is all heterologous groups with exception of group 4 (5.4% heterology). Homologous immunity protected all animals of group 2 while heterologous immunity protected at least 66% of the animals of heterologous groups which showed viremia only on day 3. In all heterologous groups a rapid and high anamnesic antibody response was observed on day 14pi and no difference in the humoral response could be demonstrated between them.
