Molecular detection of H5N1, H9N2 and Newcastle disease viruses isolated from chicken in mixed infection in Egypt

Abstract

Total of 335 fecal and nasal swabs were collected from Broilers, Broiler Breeders, Layers and duck flocks from farms and backyard in different Provinces in the period from 2011 to the year 2013. All these flocks had history for previous vaccination against avian influenza and Newcastle disease viruses. All samples were inoculated in 9-day old specific pathogenic free (SPF) embryonated chicken eggs through allantoic sac. Rapid haemagglutination (HA) test was done for detection of haemagglutaning viruses. Results of Haemagglutination revealed that, 12 (3.6%) out of 335 collected samples were positive by using HA test. The results revealed that 4 (4.4%) out of 90 broiler samples from Fayoum Governorate were positive by HA test. One sample (6.6%) out of 15 samples; 2 samples (1.3%) out of 157 samples and 2 (3.4%) out of 58 were positive by HA test in broiler, breeder and layer flocks respectively from Sharkia Governorate. In Menofia Governorate, one sample (7.7%) out of 13 from backyard and 2 samples (100%) out of 2 collected from ducks were positive by HA test. HA positive samples either Newcastle disease and/or avian influenza virus. Results of virus detection by RT-PCR using F gene primers proved that all isolated viruses were ND negative. Also, the results of RT-PCR test for H5 and H9 genes proved that AIV H5N1 virus was detected in 8 isolates (66.6%) out of 12 HA positive samples, where 5 samples (41.6%) from Sharkia and 3 samples (25%) from Menofia. Also, AIV H9N2 was detected in 9 isolates (75%) out of 12 HA positive samples, where 5 (41.6%) samples from Sharkia and 4 samples (20%) from Fayoum. © IDOSI Publications, 2013.