Efficacy of live attenuated porcine reproductive and respiratory syndrome virus 2 strains to protect pigs from challenge with a heterologous Vietnamese PRRSV 2 field strain

Table 3 Histopathological pulmonary findings in pigs challenged with an HP PRRSV 2 field strain (n = 10 per group)

	No. of piglets group 1	No. of piglets group 2
Interstitial pneumonia	4^a	10^b
Alveolar histiocytosis	4	7
Desquamative/purulent bronchitis	3	7
Dystelectasis	8	10

Group 1 – pre-vaccinated with an experimental PRRSV 2 live vaccine
Group 2 – not pre-vaccinated
Significant differences (P < 0.05) between the groups are indicated with different letters

ISSN: 1746-6148