Sally Furniss
Well-known member
Low prevalence of avian influenza antibody in backyard chickens in Bay of Plenty and South Wairarapa regions of New Zealand 2006
T. Zheng1 , B. Buddle 1 , B. Adlam 2 , S. Huang 2 , V. Hope 2 , W. Stanislawek 3 , T.
Rawdon 3 , S. Cork 3 , J. OKeefe 3 , K. Grimwood 4 , M. Baker 4
1 Animal Health, AgResearch Limited, Palmerston North, New Zealand
2 Environmental Science and Research Limited, Wellington, New Zealand
3 Biosecurity New Zealand, Wellington, New Zealand
4 University of Otago - Wellington, Wellington, New Zealand
Backyard poultry, especially ducks, have played an important role in the transmission of highly pathogenic avian influenza virus H5N1 in South East Asia.
New Zealand has never had an outbreak of avian influenza AI in poultry, although low pathogenic strains have been isolated from wild ducks.
The aim of this study was to determine whether non-pathogenic AI viruses were present in non-commercial backyard poultry in areas where wild ducks were in close proximity.
Twelve farms from both the South Wairarapa and Bay of Plenty in the lower and middle North Island, respectively, were selected on the basis of proximity to waterways where wild ducks congregate and where there were multiple poultry species.
These farms were visited between September and November 2006; blood samples, tracheal and cloacal swabs were collected from the domestic poultry.
Chicken flock sizes varied from 4 to 35 and 5 farms had multiple poultry species.
The prevalence of AI antibody in chickens, tested by IDEXX Flockchek ELISA, was 2.9% 5/173 and 4.4% 6/136 in South Wairarapa and Bay of Plenty, respectively.
The positives came from 2 farms in Bay of Plenty and 3 farms in South Wairarapa regions.
The flock prevalence varied from 6.7% 1/15 to 33.3% 4/12 in the positive farms.
All ELISA positive sera were negative for antibodies against AI subtypes H5 and H7 by haemagglutinin inhibition test.
Furthermore, no AI virus was detected in either tracheal or cloacal swabs by real-time RT-PCR.
The prevalence of AI antibody in wild mallard ducks in New Zealand has been shown to be approximately 34% Stanislawek et al, 2002 , therefore the low prevalence of AI antibody in backyard chickens may suggest low transmission frequency of AI viruses from wild ducks to backyard chickens during the study.
A longitudinal cohort study to determine the effect of farming practices and seasonality on the prevalence of AI viruses in backyard chickens is also in progress.
1 Stanislawek, W.L., et al 2002 Avian paramyxoviruses and influenza viruses isolated from mallard ducks Anas platyrhynchos in New Zealand. Archives in Virology 147:1287-1302
https://www.asnevents.net.au/abstracts/view_abstract.php?eid=EVHFEXZV29CK&num=103
T. Zheng1 , B. Buddle 1 , B. Adlam 2 , S. Huang 2 , V. Hope 2 , W. Stanislawek 3 , T.
Rawdon 3 , S. Cork 3 , J. OKeefe 3 , K. Grimwood 4 , M. Baker 4
1 Animal Health, AgResearch Limited, Palmerston North, New Zealand
2 Environmental Science and Research Limited, Wellington, New Zealand
3 Biosecurity New Zealand, Wellington, New Zealand
4 University of Otago - Wellington, Wellington, New Zealand
Backyard poultry, especially ducks, have played an important role in the transmission of highly pathogenic avian influenza virus H5N1 in South East Asia.
New Zealand has never had an outbreak of avian influenza AI in poultry, although low pathogenic strains have been isolated from wild ducks.
The aim of this study was to determine whether non-pathogenic AI viruses were present in non-commercial backyard poultry in areas where wild ducks were in close proximity.
Twelve farms from both the South Wairarapa and Bay of Plenty in the lower and middle North Island, respectively, were selected on the basis of proximity to waterways where wild ducks congregate and where there were multiple poultry species.
These farms were visited between September and November 2006; blood samples, tracheal and cloacal swabs were collected from the domestic poultry.
Chicken flock sizes varied from 4 to 35 and 5 farms had multiple poultry species.
The prevalence of AI antibody in chickens, tested by IDEXX Flockchek ELISA, was 2.9% 5/173 and 4.4% 6/136 in South Wairarapa and Bay of Plenty, respectively.
The positives came from 2 farms in Bay of Plenty and 3 farms in South Wairarapa regions.
The flock prevalence varied from 6.7% 1/15 to 33.3% 4/12 in the positive farms.
All ELISA positive sera were negative for antibodies against AI subtypes H5 and H7 by haemagglutinin inhibition test.
Furthermore, no AI virus was detected in either tracheal or cloacal swabs by real-time RT-PCR.
The prevalence of AI antibody in wild mallard ducks in New Zealand has been shown to be approximately 34% Stanislawek et al, 2002 , therefore the low prevalence of AI antibody in backyard chickens may suggest low transmission frequency of AI viruses from wild ducks to backyard chickens during the study.
A longitudinal cohort study to determine the effect of farming practices and seasonality on the prevalence of AI viruses in backyard chickens is also in progress.
1 Stanislawek, W.L., et al 2002 Avian paramyxoviruses and influenza viruses isolated from mallard ducks Anas platyrhynchos in New Zealand. Archives in Virology 147:1287-1302
https://www.asnevents.net.au/abstracts/view_abstract.php?eid=EVHFEXZV29CK&num=103