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Porcine Reproductive and Respiratory Syndrome (view source)
Revision as of 19:56, 27 August 2010
, 19:56, 27 August 2010→Pathology
After an uncomplicated PRRS infection in finishing pigs, gross lesions can vary from unremarkable to severe. In severe disease, lungs are mottled red and tan, and fail to collapse properly. The cranioventral lobes are worst affected. Lymph nodes appear moderately to severely enlarged, tan in colour and may be haemorrhagic with some strains of virus. Most PRRS virus-infected pigs are co-infected with one or more secondary pathogens, so pathology can vary quite widely depending on these. Microscopically, interstitial pneumonia is the typical finding. There is a mononuclear infiltration of the alveolar walls with type 2 pneumonocyte proliferation, and necrotic debris and macrophages accumulate in the alveolar spaces. In lymph nodes, follicular hyperplasia and necrosis may be seen. Non-suppurative meningoencephalitis and choroiditis is commonly present, but severity is highly variable.
After an uncomplicated PRRS infection in finishing pigs, gross lesions can vary from unremarkable to severe. In severe disease, lungs are mottled red and tan, and fail to collapse properly. The cranioventral lobes are worst affected. Lymph nodes appear moderately to severely enlarged, tan in colour and may be haemorrhagic with some strains of virus. Most PRRS virus-infected pigs are co-infected with one or more secondary pathogens, so pathology can vary quite widely depending on these. Microscopically, interstitial pneumonia is the typical finding. There is a mononuclear infiltration of the alveolar walls with type 2 pneumonocyte proliferation, and necrotic debris and macrophages accumulate in the alveolar spaces. In lymph nodes, follicular hyperplasia and necrosis may be seen. Non-suppurative meningoencephalitis and choroiditis is commonly present, but severity is highly variable.
There are no gross lesions noted in aborted or stillborn fetuses, but histopathology inconsistently reveals interstitial pneumonia, myocarditis and pulmonary arteritis. However, these changes are neither specific nor diagnostic for PRRS.
There are no gross lesions noted in aborted or stillborn foetuses, but histopathology inconsistently reveals interstitial pneumonia, myocarditis and pulmonary arteritis. However, these changes are neither specific nor diagnostic for PRRS.
==Treatment and Control==
==Treatment and Control==