Sayed Rasoul Zaker; Hassan Nili; Keramat Asasi
Volume 13, Issue 3 , September 2022, , Pages 439-441
Abstract
Avian influenza virus subtype H9N2 is widely circulating around the globe affecting many species of animal including mammals and birds as well as human beings. The virus has pandemic potential due to segmented nature of the viral genome. Ultra-structural features of apoptosis in field and experimental ...
Read More
Avian influenza virus subtype H9N2 is widely circulating around the globe affecting many species of animal including mammals and birds as well as human beings. The virus has pandemic potential due to segmented nature of the viral genome. Ultra-structural features of apoptosis in field and experimental infection of H9N2 avian influenza virus were studied. Freshly dead birds from affected broiler farms and experimentally infected broiler chickens with H9N2 subtypes were subjected to routine necropsy. Post-mortem findings in different organs were recorded. Appropriate specimens from the trachea were taken for electron microscopy studies. In electron microscopy study, frequent apoptotic bodies were observed in the epithelial cells of trachea. Increase of antibody titer to H9N2 virus following challenge with the virus in experimental group indicates that the infectious cycle has been initiated in the affected birds.
Mohsen Kalantari; Hassan Sharifiyazdi; Keramat Asasi; Bahman Abdi-Hachesoo
Volume 12, Issue 1 , March 2021, , Pages 101-107
Abstract
The objective was to investigate the multidrug resistance and presence of class 1 and 2 integrons in 300 Escherichia coli isolates obtained from 20 broiler farms during three rearing periods (one-day-old chicks, thirty-day-old chickens, and one day before slaughter) in Fars, South Iran. Results ...
Read More
The objective was to investigate the multidrug resistance and presence of class 1 and 2 integrons in 300 Escherichia coli isolates obtained from 20 broiler farms during three rearing periods (one-day-old chicks, thirty-day-old chickens, and one day before slaughter) in Fars, South Iran. Results showed that 81.00%, 82.00%, and 85.00% of isolates were multidrug-resistant on the first day, thirty-day-old chickens, and one day before slaughter, respectively. Multidrug-resistant E. coli isolates were further examined for the presence of class 1 and 2 integrons using PCR assay. The existence of class 1 integron-integrase gene (intI1) was confirmed in 68.40%, 72.70%, and 60.90% of multidrug-resistant isolates from stage 1, stage 2, and stage 3 of the rearing period, respectively. The frequency of class 2 integron-integrase gene (intI2) during the first to the third stage of sampling was 2.60%, 25.50%, and 30.40%. Also, sequence analysis of the cassette arrays within class 1 integron revealed the presence of the genes associated with resistance for trimethoprim (dfrA), streptomycin (aadA), erythromycin (ereA), and orfF genes. The results revealed that percentages of antimicrobial resistance in E. coli isolates were significantly higher in the middle and end stages of the rearing period. In conclusion, widespread dissemination of class 1 integrons in all three stages and rising trends of class 2 integrons existence in E. coli isolates during the rearing period of broiler chickens could exacerbate the spread of resistance factors among bacteria in the poultry industry. Future research is needed to clarify its implication for human health.
