Occurrence and phylogenetic analysis of bovine respiratory syncytial virus in outbreaks of respiratory disease in Norway

Abstract

BackgroundBovine respiratory syncytial virus (BRSV) is one of the major pathogens involved in the bovine respiratory disease (BRD) complex. The seroprevalence to BRSV in Norwegian cattle herds is high, but its role in epidemics of respiratory disease is unclear. The aims of the study were to investigate the etiological role of BRSV and other respiratory viruses in epidemics of BRD and to perform phylogenetic analysis of Norwegian BRSV strains.ResultsBRSV infection was detected either serologically and/or virologically in 18 (86%) of 21 outbreaks and in most cases as a single viral agent. When serology indicated that bovine coronavirus and/or bovine parainfluenza virus 3 were present, the number of BRSV positive animals in the herd was always higher, supporting the view of BRSV as the main pathogen. Sequencing of the G gene of BRSV positive samples showed that the current circulating Norwegian BRSVs belong to genetic subgroup II, along with other North European isolates. One isolate from an outbreak in Norway in 1976 was also investigated. This strain formed a separate branch in subgroup II, clearly different from the current Scandinavian sequences. The currently circulating BRSV could be divided into two different strains that were present in the same geographical area at the same time. The sequence variations between the two strains were in an antigenic important part of the G protein.ConclusionThe results demonstrated that BRSV is the most important etiological agent of epidemics of BRD in Norway and that it often acts as the only viral agent. The phylogenetic analysis of the Norwegian strains of BRSV and several previously published isolates supported the theory of geographical and temporal clustering of BRSV.

Evidence of respiratory syncytial virus and parainfluenza-3 virus in Mexican sheep

“…VRS has also been isolated and sequenced from bovines in countries like Brazil and Norway [18,37]. A new member of the respirovirus genus, called Caprine Parainfluenza 3 virus, was recently reported in goat herds [48]; however, to date there are no reports on the isolation or detection of PI3V or VRS specific for sheep, even though respiratory diseases in small ruminants proved to be one of the main causes of losses in the herd [25].…”

Evaluation of a multiplex immunoassay for bovine respiratory syncytial virus and bovine coronavirus antibodies in bulk tank milk against two indirect ELISAs using latent class analysis

“…Bovine coronavirus (BCV) and bovine respiratory syncytial virus (BRSV) are commonly occurring agents among cattle worldwide (Valarcher and Taylor, 2007;Boileau and Kapil, 2010). They are endemic and prevalent also in the Norwegian dairy herd (Gulliksen et al, 2009;Klem et al, 2014a). BCV causes respiratory disease, calf diarrhea and winter dysentery (contagious diarrhea in adult cattle) (Boileau and Kapil, 2010).…”

“…BCV causes respiratory disease, calf diarrhea and winter dysentery (contagious diarrhea in adult cattle) (Boileau and Kapil, 2010). BRSV causes respiratory disease mostly in young animals but can affect animals of all ages, and is a common cause of respiratory outbreaks in Norway (Larsen, 2000;Klem et al, 2014a). Consequences of these infections are herd health problems, reduced animal welfare and increased use of antibiotics due to secondary bacterial infections (Larsen, 2000;Valarcher and Taylor, 2007;Boileau and Kapil, 2010).…”

Bovine respiratory syncytial virus and bovine coronavirus antibodies in bulk tank milk – risk factors and spatial analysis

“…BRSV causes respiratory disease, most often in young animals, and bronchopneumonia due to secondary bacterial infection is common (Larsen, 2000). BRSV was the most commonly isolated agent in respiratory outbreaks in cattle herds in a recent Norwegian study (Klem et al, 2014a). BCoV is the cause of calf diarrhea, respiratory disease and winter dysentery (contagious diarrhea in adult cattle) (Boileau and Kapil, 2010) have shown significant effects of BCoV infection on production in terms of decreased milk yield and poor growth rate (Tråvén et al, 2001;Beaudeau et al, 2010b) which both result in economic loss.…”