Porcine reproductive and respiratory syndrome virus: Age and management system disease modeling for pathogenic co-infection
نویسندگان
چکیده
Materials and methods: Pigs 3, 9, 16, and 24 weeks of age from 41 sow sources representing one-, two-, and three-site production systems were necropsied on the basis of acute, subacute, and chronic disease stages (n = 5 animals per age group per farm). Logistic regression models were used to assess co-infection with other pathogens, serological profiles, and histopathological lesions in pigs PRRSV-positive by polymerase chain reaction and with lung lesions consistent with PRRSV infection, and in PRRSV-negative pigs. Additional models were stratified by age and type of production system.
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