title: A survey of avian paramyxovirus type 1 infections among backyard poultry in New Zealand.
abstract: OBJECTIVE
  To determine the presence and the pathotype of avian paramyxovirus type 1 (APMV-1), as well as the prevalence of APMV-1 antibodies, among backyard flocks of poultry in selected New Zealand locations.
  
  
  METHODS
  Archival pooled (n = 162) tracheal and cloacal swabs collected from backyard poultry were tested for the presence of APMV-1 RNA by real-time and conventional reverse transcription (RT)-PCR assays. Archival blood samples (n = 240) from a subpopulation of the same birds were tested for the presence of the APMV-1 antibody using a commercial ELISA assay. The archival samples were collected from geographical areas close to bodies of water, in the Bay of Plenty or Wairarapa regions of the North Island of New Zealand, with the high likelihood of interactions between wild waterfowl and domestic poultry.
  
  
  RESULTS
  Avian paramyxovirus type 1 RNA was not detected in any of the swabs tested. Antibodies to APMV-1 were detected on 18/19 farms, in 71/240 (29.5%) blood samples tested. The percentage of seropositive birds varied between seropositive farms and ranged from 8.3 to 100%. The percentage of seropositive birds on each farm was not statistically correlated with the flock size, the number of birds sampled, the number of farmed waterfowl, or with the distance to the closest lake/river. However, all chickens from the farm with the highest number of farmed ducks were seropositive for APMV-1.
  
  
  CONCLUSIONS
  Lack of detection of APMV-1 in any of the samples indicates that APMV-1 was not circulating among the poultry at the time of sampling. However, detection of APMV-1 antibodies in a proportion of birds on each farm indicates that infection with APMV-1, or antigenically related APMV, is common among backyard poultry.
  
  
  CONCLUSIONS
  On-going proactive surveillance and characterisation of circulating APMV-1 is important for monitoring changes in circulating genotypes of APMV-1 and for understanding the regional ecology of these viruses for the purpose of planning appropriate disease control and prevention strategies. Our data suggest that backyard flocks should be considered as potential reservoirs of APMV. Chickens from backyard farms with multiple bird species may provide good targets for surveillance purposes.
authors.affiliation: a Institute of Veterinary Animal and Biomedical Sciences, Massey University , Private Bag 11 222, Palmerston North 4474 , New Zealand.
authors.forename: M
authors.initials: M
authors.lastname: Dunowska
authors.forename: T
authors.initials: T
authors.lastname: Zheng
authors.forename: M R
authors.initials: MR
authors.lastname: Perrott
authors.forename: N
authors.initials: N
authors.lastname: Christensen
mesh_terms: D000818:Animals; D001483:Base Sequence; D008969:Molecular Sequence Data; D009520:New Zealand / Q000453:epidemiology; D009521:Newcastle Disease / Q000097:blood / Q000453:epidemiology* / Q000821:virology; D009522:Newcastle disease virus; D011200:Poultry; D012698:Serologic Tests / Q000662:veterinary