Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5798798 | The Veterinary Journal | 2013 | 6 Pages |
The objective of this study was to compare the virulence of Korean types 1 and 2 porcine reproductive and respiratory syndrome virus (PRRSV) isolated from weaned pigs with respiratory disease. Affected pigs were within the same herd and animals infected with type 2 virus had significantly higher mean rectal temperatures than those with type 1 virus between days 2 and 9 post-inoculation (PÂ <Â 0.05). Similarly, mean serum viral titres, expressed as tissue culture infective doses 50% (TCID50)/mL, as well as macroscopic and microscopic pulmonary lesion scores, were significantly higher at multiple time points in pigs infected with type 2 PRRSV compared to those infected with type 1 virus. Mean numbers of PRRSV-positive cells/unit area of lungs and lymph nodes were also significantly higher in type 2 PRRSV infected pigs. This study demonstrates that type 2 PRRSV is more virulent than type 1 PRRSV in this experimental setting as reflected by the pulmonary pathology induced, the extent of virus distribution, and oral shedding of the virus.