Study on virulent stability of highly pathogenic PRRS virus KTY-PRRS-06 through 5 infusion inoculation generations on pigs

Abstract

Study on virulent stability of highly pathogenic PRRS virus, KTY-PRRS-06 through 5 infusion inoculation generations was carried out on the 2 months old pigs. The experimental pigs were infected by virus suspension with a dose of 2 ml/pig through nasal route in the first generation and from generations 2st to 5th, infusion route was applied. After infection, the experimental pigs were monitored for clinical signs, virus replication in the blood, gross and histological lesions at some internal organs. The studied results obtained from 5 generations of infusion inoculation were similar, such as: the clinical symptoms of the experimental pigs after infection were moodiness, fatigue, anorexia, high fever, labored breathing, skin rash and constipation. The gross lesions focused mainly on the lung and lymph nodes, the lung was congested and bled interstitial pneumonia, lung lymph nodes were swollen and congested. The kidneys were bled, pericardium was watery. The histological lesions included: broncho-alveolar inflammation, lobar pneumonia, hemorrhagic glomeruli. The above mentioned results indicated that PRRS virus strain KTY-PRRS-06 could cause PRRS and performed the virulent stability through 5 infusion inoculation generations on the experimental pigs.