Mannheimia haemolytica serovars associated with respiratory disease in cattle in Great Britain.

Background: Mannheimia haemolytica is commonly associated with respiratory disease in cattle worldwide as a cause of fibrinous pneumonia, bronchopneumonia and pleuritis. M. haemolytica is further subdivided into 12 serovars, however not all are considered to be pathogenic in cattle.

Use of tissue swabbing as an alternative to tissue dissection and lysis prior to nucleic acid extraction and real-time polymerase chain reaction detection of Bovine viral diarrhea virus and Porcine reproductive and respiratory syndrome virus.

The use of swabbing to sample tissue samples, prior to nucleic acid extraction and performance of a real-time polymerase chain reaction (PCR) assay, was investigated for the detection of the viral pathogens Bovine viral diarrhea virus (BVDV) and Porcine reproductive and respiratory syndrome virus (PRRSV). The tissue swabbing method involved swabbing recently cut tissues, eluting the swabbed material, and extracting nucleic acid from the eluate prior to PCR amplification. Parallel testing of this method with traditional nucleic acid extraction from tissues, where small pieces of tissue are dissected and digested (typically overnight) in lysis buffer prior to nucleic acid extraction, was carried out for 50 samples for each virus.

Porcine reproductive and respiratory syndrome virus: interlaboratory ring trial to evaluate real-time reverse transcription polymerase chain reaction detection methods.

To compare the real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) assays used for the diagnosis of Porcine reproductive and respiratory syndrome virus (PRRSV), a Europe-wide interlaboratory ring trial was conducted. A variety of PRRSV strains including North American (NA) and European (EU) genotype isolates were analyzed by the participants. Great differences regarding qualitative diagnostics as well as analytical sensitivity were observed between the individual RT-qPCR systems, especially when investigating strains from the EU genotype.

Porcine reproductive and respiratory syndrome virus: antigenic and molecular diversity of British isolates and implications for diagnosis.

Porcine reproductive and respiratory syndrome (PRRS) is an endemic disease of pigs, caused by PRRS virus, a member of the Arteriviridae family. First seen in Britain in 1991, the disease continues to be a significant economic and welfare problem for pig producers. To date, only PRRSV genotype 1 has been found in Britain.