Infectious bronchitis (IB) is a viral avian disease with economic importance in the world, including Iran. S1 gene sequencing has been used for molecular epidemiological studies and genotypic characterization of infectious bronchitis virus (IBV). A total of 118 IBV isolates were obtained from tissue samples from chickens with clinically suspected IB from Iranian broiler farms (eight provinces, 200 samples). The isolates were confirmed by real-time polymerase chain reaction (PCR) and characterized by sequencing the spike glycoprotein gene. The isolates formed six distinct phylogenetic groups (IS/1494/06 [Var2] like, 4/91-like, IS/720-like, QX-like, IR-1 and Mass-like) that were related to variants isolated in the region. The most frequently detected viruses were of the Var2-like (IS/1494/06-like) genotype, with an overall prevalence of 34 %. Twenty-one percent of the isolates formed a cluster together with the 4/91 IBV type, 10 % were of the QX genotype, and 8 % were of the IS/720 genotype. In addition, 4 % and 3 % of the isolates belonged to the Massachusetts and IR-1 genotype, respectively. For the first time, we have isolated and characterized IBV variants from broiler farms in different provinces of Iran. This study demonstrates a constant evolution of IBV in Iran, demonstrating the need for continuous monitoring and development of new vaccines based on indigenous viruses.

Background Salmonella enterica serovar Enteritidis (S. Enteritidis) is one of the most common serovars, associated with human salmonellosis. The food-borne outbreak of this bacterium is mainly related to the consumption of contaminated poultry meat and poultry products, including eggs. Therefore, rapid and accurate detection, besides investigation of virulence characteristics and antimicrobial resistance profiles of S. Enteritidis in poultry and poultry egg samples is essential. A total of 3125 samples (2250 poultry and 875 poultry egg samples), sent to the administrative centers of veterinary microbiology laboratories in six provinces of Iran, were examined for Salmonella contamination, according to the ISO 6579 guideline. Next, duplex PCR was conducted on 250 presumptive Salmonella isolates to detect invA gene for identification of the genus Salmonella and sdf gene for identification of S. Enteritidis. Subsequently, the S. Enteritidis isolates were examined for detection of important virulence genes (pagC, cdtB, msgA, spaN, tolC, lpfC, and spvC) and determination of antibiotic resistance patterns against nalidixic acid, trimethoprim-sulfamethoxazole, cephalothin, ceftazidime, colistin sulfate, and kanamycin by the disk diffusion method. Results Overall, 8.7 and 2.3% of poultry samples and 6.3 and 1.3% of eggs were contaminated with Salmonella species and S. Enteritidis, respectively. The invA and msgA genes (100%) and cdtB gene (6.3%) had the highest and the lowest prevalence rates in S. Enteritidis isolates. The spvC gene, which is mainly located on the Salmonella virulence plasmid, was detected in 50.8% of S. Enteritidis isolates. The S. Enteritidis isolates showed the highest and the lowest resistance to nalidixic acid (87.3%) and ceftazidime (11.1%), respectively. Unfortunately, 27.0% of S. Enteritidis isolates were multidrug-resistant (MDR). Conclusion The rate of contamination with Salmonella in the poultry and egg samples, besides the presence of antimicrobial resistant and MDR Salmonella isolates harboring the virulence genes in these samples, could significantly affect food safety and subsequently, human health. Therefore, continuous monitoring of animal-source foods, enhancement of poultry farm control measures, and limiting the use of antibiotics for prophylactic purposes in food producing animals, are essential for reducing the zoonotic risk of this foodborne pathogen for consumers and also choosing effective antibiotics for the treatment of salmonellosis.

Avian infectious bronchitis (IB) is a worldwide chicken disease, caused by avian infectious bronchitis virus (IBV) which infects all commercial poultry lines. The present study was done to evaluate protection caused by two different serotype vaccines (Massachusetts and 793/B) in order to evaluate protection against challenge with IS/1494/06-like virus (variant 2-like virus), which is prevalent in the Middle East. SPF chickens were divided into four groups (n = 20). First and second group as negative control group and non-vaccinated-challenged group received no vaccine. Groups 3 and 4 received H120-H120 and H120-1/96 IBV vaccine strains at the 1st and 14th day, respectively. Twenty one days after last vaccination, non-vaccinated-challenged group and vaccinated group were challenged using variant 2-like IBV. Serum samples were collected before challenge to measure humoral immune response of chickens. Five days after challenge, the tissue samples from the trachea, lungs and kidneys were taken to evaluate cilliary activity, viral load (quantitative real-time RT-PCR), and histopathological evaluation. Clinical sign scores were also recorded after challenge. Overall, the results showed a protective efficacy of the used vaccination program. Best cross protection (69.2%) was obtained in the H120-1/96 vaccinated group. Virus replication of the challenged virus in H120-1/96 group compared with H120-H120 group showed a significant reduction of viral load in trachea (1.5×103 compared to 503) and kidneys. Clinical sign scores of the challenged groups showed significant effect of the vaccination program to reduce clinical signs. The trachea pathological scores and histopathological findings in the lungs and kidneys also confirmed better protective efficacy of vaccinated groups. In conclusion, using combination of heterologous IBV vaccine serotypes (Massachusetts and 793/B) would be a better strategy to control variant 2-like viruses, but more evaluation is needed using other circulating isolates to find the best combination of vaccines.

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Summary. -Avian infectious bronchitis (IB) is a major cause of economic loss to the poultry industry. IB virus primarily affects respiratory tract, but strains differ in their tropism for such other target organs as kidneys and alimentary tract. The objective of this study was to estimate the pathogenicity of an Iranian IB virus (IBV) variant (variant-2) which is one of the most prevalent isolates circulating in Iranian poultry farms. SPF chickens were intranasally inoculated with 10 4 EID 50 /0.1 ml of the virus. Sera, fecal swabs, and different tissue samples were collected on different days post infection. Clinical signs, gross pathology, and histological changes were recorded. The amount of virus genome was quantified in different tissues and feces using quantitative real-time PCR assay. The highest viral loads were detected in the feces and cecal tonsils. Real-time PCR results demonstrated variant-2 tropism for respiratory tract, digestive system and renal tissue that is due to its epitheliotropic nature. This is the first pathogenicity study of Iranian variant-2 virus. Based on histology observations and clinical signs this isolate was classified as a nephropathogenic IBV. Further knowledge of IBV pathogenesis permits to perform more effective prevention practice.

Haemosporidian parasites characterize multi-host and multi-parasite structures which are prevalent among wild bird populations. Here, determination of host records, estimation of the prevalence and diversity of haemosporidian lineages were performed in wild and domestic birds in 11 provinces in Iran. To our knowledge, for the first time in this region, molecular characterization of haemosporidians in migratory water birds, raptors, and domestic birds was carried out: blood or tissue samples were collected from 246 birds belonging to 36 species, 12 families, and 11 orders. The prevalence of Plasmodium , Haemoproteus, and Leucocytozoon were documented as 1.21%, 3.65%, and 0.4%, respectively. Of 36 birds' species inspected in this investigation, 13 individuals of 9 species were parasitized by blood parasites. To our knowledge, five lineages including hANACRE03, hAYTFER01, hAYTFER02, hAQUCYR01, and hSTAL06 were found as un-described lineages, while six known lineages of hLK03, pLK05, lTUSW04, pSW5, hMILANS02, and hHAECOL1 were recorded in hosts within novel geographical regions. Such results are required to fill the gaps in understanding the geographical distribution patterns of wildlife related vector-borne parasites in migratory birds as potential carriers, raptors with high vulnerability, and domestic birds as pet or with economic value.

Infectious bronchitis virus (IBV) is a highly infectious pathogen, which affects the respiratory tract, reproductive system, and kidney of chickens. Many different genotypes of IBV are recognized which cause different clinical manifestations. According to the antigenic differences, different serotypes of the virus do not cross-protect. Massachusetts serotype induces the best cross-protection against other serotypes. Recently, the IBV QX genotype has been detected in Iran. QX genotype causes permanent damage to the oviduct in layer and breeder flock if it occurs in the early life cycle. In this study, we compared two vaccination program using 793/B type and Massachusetts type vaccine. One-day-old SPF chickens were divided into four groups. Groups 1 and 2 were unvaccinated groups. Group 3 was vaccinated with the H120 vaccine at day 1 and 793/B at day 14 (eye drop), and group 4 was vaccinated with H120+793/B (eye drop) on the first day and 793/B at day 14. Groups 2, 3, and 4 challenged (oculonasal) with QX genotype (10 4 EID50) at day 35. Five days post challenge, the sample were clollected for ciliostasis test, histopathology, and quantitative real-time RT-PCR from trachea, lung, and kidneys. Results showed that two vaccination programs created more than 80% of protection against challenge virus, but no significant difference was recorded between two programs. Based on our results, it can be concluded that vaccination with two mixed vaccines (H120+793/B) on the first day of the life of a chick does not make any difference in comparison to single vaccine (H120) in reducing of pathological damages and viral load. As long as the second vaccination against IB may not be applied properly in farm situation, applying the mixture of 793/B type vaccine with H120 at day 1 (ocular or spray) may help to increase vaccination program efficacy.

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