Infectious bronchitis virus (IBV) in vaccinated chicken flocks continues to cause enormous economic losses to the poultry industry in Iran. A molecular surveillance of IBV genotypes involved in outbreaks of disease was performed. Specimens of trachea, kidney, and cecal tonsil were collected from 250 suspected flocks (more than 2500 samples) and identified between 2010 and 2014. Partial spike glycoprotein gene sequences revealed seven distinct genotypes, including Mass, 793/B, IS720, Variant 2, QX, IR-I, and IR-II, to be circulating in the chicken farms. The majority of flocks (67.6%) experienced infection with an IBV variant unrelated to the vaccine strains. These variants displayed homologies ranging from 54.1% to 78.5% and from 53% to 86% with H120 and 4/91, respectively. These findings reveal the existence of IBV variants genetically different from the vaccine strains currently in use and explain the outbreaks of disease observed in the field. The current work constitutes the first comprehensive survey of IBV in Iran and emphasizes the need for continuous monitoring and rethinking of current preventative measures.

Twenty-four fowl adenoviruses (FAdVs) were isolated from broiler and broiler breeder pullet flocks in Iran during 2013-2016 and were identified and characterized. All FAdVs were from inclusion body hepatitis (IBH) cases, showing an enlarged and pale yellow liver with multiple petechial hemorrhages. Phylogenetic analyses of partial hexon gene sequences are an adequate and quick method for differentiation and genotyping. The isolates were subjected to PCR to amplify a 590-bp fragment from the hexon gene. Sequence analysis revealed the presence of two species D and E. Eighty FAdV isolates were genetically related to the strain EU979378 of FAdV-11 (96.5% to 97.6% identity), and six isolates were related to the strain EU979375 of FAdV-8b (97% identity). The results indicated that two FAdV serotypes (11 and 8b) are high prevalence serotypes of FAdVs in Iran and are pathogenic enough to cause IBH in young chicks. Therefore, preventive measures against FAdV infection on poultry farms should be implemented.

The present study was designed to compare the anatomical parameters of the cardiopulmonary system in three different lines of chickens with different susceptibility to ascites syndrome. Eggs from three different genetic lines-commercial broiler and layer lines and one native to Iran--were incubated and hatched, and 1-day-old chicks used. The relative heart and lung weights, the volumes of the heart, lung and thorax cavity, the incidence of ascites, and the related physiological parameters in these chickens were followed. Lung weight as a percentage of body weight, the relative lung and heart volume, and the volumes of the thorax cavity, before and after removing heart and lung tissues, were lower in fast-growing broiler chickens compared with the layer and native chickens. Additionally, most of these parameters (e.g. relative lung weight, lung volume and thorax cavity) were significantly decreased with age in broiler chickens but were increased in layer and native chickens, which was concomitant with the incidence of ascites in broiler chickens. Our data indicate that all cardiopulmonary parameters investigated are extremely unfavourable to broiler chickens and suggest a reduction in gas exchange area in broilers, and therefore higher susceptibility to pulmonary hypertension and ascites.

Summary In 1995, a peste des petits ruminants (PPR) outbreak was diagnosed in Ilam province in Iran near the border with Iraq both serologically and virologically. As then, despite all control measures, PPR has been identified in the whole country and has led to costs of at least US$1.5 million to the Iranian owners of sheep and goats.

To evaluate the prevalence of infectious bronchitis virus (IBV) type 4/91 in Iran, tracheal swabs from 77 broiler flocks in 16 provinces were collected at the slaughterhouse. Swabs were subjected to RNA extraction and tested by RT-PCR, followed by a type-specific nested PCR. The viral RNA was detected in 33 samples (42.8%) from different provinces. The results indicate a relatively high prevalence of IBV type 4/91 in Iran and necessitate revising the vaccination programme against this disease.