Iranian Journal of

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  Background and Objectives : Influenza is an acute, contagious, and zoonotic viral disease. It is caused by a virus of the Orthomyxoviridae family. This very infectious is caused by different subtypes of type A influenza virus in the poultry, turkey, and many other birds. In this study, the serum status of rural domestic poultry was investigated for influenza subtype H9N2.

 Methods: This cross sectional study was done from August to October in 2013 in Iranian villages through sampling domestic poultry. The sampling was accidental and was done based on the GIS 11-digit code. In each village, blood samples were taken from at least 28 birds from different species. Then, ELISA was used for screening followed by the HI test. A total of 397 villages and 11546 birds (10145 chickens, 1413 ducks, 397 turkeys, 10 pigeons, and 175 other species) were sampled.

  Results : Three hindered and forty nine (88%) out of 397 villages were positive on ELISA. In addition, 341 villages (86%) were positive and 56 (14%) were negative on the HI test for antibody titers. Also, among the considered variables, weather was a risk factor and the prevalence was significantly lower in villages near the rivers, lagoons and lakes (up to a radius of 3 Km).

  Conclusion: The high seroprevalence of influenza H9N2 in rural domestic poultry indicates that the disease is becoming endemic. As there is no eradication policy for influenza H9N2 in Iran, using effective vaccines can reduce the infection with influenza virus in domestic and rural poultry.

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Background and Objectives: Influenza is an acute, highly contagious disease of a variety of both domestic and wild bird species. The aim of this study was to estimate subclinical infections or previous exposure to H5 and H7 subtypes and to discover potentially important determinants of the prevalence of this disease in industrial and backyard poultry in Iran.

Methods: A survey was conducted from September to December 2014 in Iran using a cross-sectional design throughout the entire country. The Enzyme-Linked Immunosorbent Assay (ELISA) was used as the screening test and all ELISA-positive samples were examined with the HI test to differentiate H5 and H7. A total of 1378 places and 31547 birds were sampled.

Results: One place (bird garden) out of 1378 was positive for the H7 subtype and six places (2 bird gardens, 3 villages, and 1 ostrich farm) out of 1378 were positive for the H5 subtype on HI test. The results of this study showed that the presence of a lake (OR=12.20, CI 95% 2.19-68.09) and live bird marketing (11.73, CI 95% 1.32-104.42) were risk factors for the H5 subtype.

Conclusion: Sampling migratory waterfowl birds is recommended for early detection of probable infections and preventing the spread of infection to the backyard and industrial poultry because of their role in the transmission of the disease and probability of circulation of the virus.

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Background and Objectives: The commercial layer chicken farming is one of the most important sectors of the poultry industry. This study was conducted to evaluate the status of biosecurity of commercial layer chicken farms in 9 Iranian provinces with the highest layer chicken population.
 
Methods: In this cross-sectional study, 202 commercial layer chicken farms were selected from nine Iranian provinces in 2019 using stratified random sampling. Then, the required data were collected using a questionnaire by presenting to the farms in person. The results are expressed as mean, standard variation, sum and adoption rate index.
 
Results: The results showed that the adoption level of total biosecurity measures was 68.18% in the commercial layer chicken farms in Iran. This figure was 72.11%, 75% and 60.82% for conceptual, structural and operational biosecurity measures, respectively. Among conceptual biosecurity measures, the lowest adoption level (29.20%) was for distance to the nearest garden and agriculture land. Among structural biosecurity measures, the lowest adoption level (28.96%) was for a hand disinfection spot before shed. Among the operational biosecurity measures, the lowest adoption level was for water filtrations (31.18%) and microbial testing of water (33.91%).
 
Conclusion: This study investigated the biosecurity status of commercial layer chicken farms in nine Iranian provinces with the highest layer chicken population and revealed some weaknesses in the implementation of these measures at conceptual, structural and operational levels.