Risk factors associated with endemic reproductive deficiencies caused by PRRSV infection

Results: Seven of 27 herds (26%) were categorized as chronic PRRSV-positive breeding herds, while the other 20 were categorized as “recovered.” Two logistic models were produced for the chronic herds: one containing management factors statistically associated with a chronic PRRSV status (raising own replacement gilts, isolation of new breeding stock, number of sows per farrowing room, and inventory of growing pigs), and one identifying herd attributes (parity and sow inventory) that were associated with a chronic PRRSV status. Implications: PRRSV-positive herds can have chronic reproductive losses in which some reproductive parameters will not return to 90% of prediagnosis levels. Certain herd attribute/management factors are associated with increased or decreased risk.