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Newcastle disease virus (NDV), avian influenza virus (AIV), and infectious bronchitis virus (IBV) are the most prevalent viral pathogens in the Iranian poultry industry. This study aimed to reveal the presence of these viruses in the backyard chickens in Ahvaz, located in the Southwest of Iran. A total of 100 chickens with respiratory signs and mortality were examined by taking the blood samples as well as tracheal and cloacal swabs. Most of the chickens had not received any vaccine. The blood samples were assessed for the antibodies against NDV and AIV by haemagglutination inhibition test, and against IBV by enzyme-linked immunosorbent assay. The swab samples were utilized for molecular detection using reverse transcription polymerase chain reaction (RT-PCR). Based on the results of the serologic test, 77%, 45%, and 38.4% of the birds were positive for NDV, AIV, and IBV, respectively. In the RT-PCR, 95% of the birds were positive for one of the three viruses. The detection rates of NDV, AIV, and IBV were 60%, 34%, and 55%, respectively. The coinfections of AIV/NDV, AIV/IBV, NDV/IBV, and AIV/NDV/ IBV were observed in 13%, 4%, 23%, and 7% of the sampled chickens, respectively. The results demonstrated that the Iranian backyard chickens were infected with NDV, AIV, and IBV. This could pose a threat to the commercial poultry; therefore, preventive measures need to be implemented in this regard.

Newcastle disease (ND) is a highly contagious infection of many avian species, mainly chickens and turkeys, with a devastating impact on worldwide poultry production. The ND accounts for heavy losses in Iranian poultry flocks. There are some reports regarding the epidemiology of this infection in Iran. This study was performed to investigate the infection of turkeys with a Newcastle disease virus (NDV) isolated from a broiler chicken flock in southwestern Iran during 2013. For the purpose of the study, 70 day-old Wishard bronze poults were allocated into two groups of control (n=25) and infected (n=45). At 32 days of age, each bird in the infected group was inoculated with 0.1 mL (50 μL per eye) of NDV-infected allantoic fluid through an ocular route and received 105 EID50 of viral inoculum. On the other hand, the birds in the control group were inoculated with phosphate buffered saline by the same route. Swab samples were taken from both groups at different time points, namely from 1 to 21 days postinoculation, and verified for NDV infection by using reverse transcription-polymerase chain reaction (RT-PCR). Both groups were also examined serologically by haemagglutination inhibition test. Clinically, the infected turkeys exhibited anorexia, severe depression, sitting on the hock joint, white to greenish (sometimes bloody) diarrhea, neurological disorders, and mild respiratory problems. Out of 45 inoculated birds, 9 (20%) cases died. Based on RT-PCR, virus shedding was observed in the challenged birds 3-8 days postinoculation. The NDV was detected more in tracheal swabs (50%) than in cloacal swabs (12.5%). The infected birds showed a high seroconversion. Therefore, the NDV circulating in Iranian chicken flocks has the potential to cause a serious illness in commercial turkeys. The vaccination of turkeys, as well as biosecurity, should be considered carefully to prevent the ND outbreaks in the future.

International audience; Visible Light Communication (VLC) is recognized as a complement communication technology that meets many hurdles of Radio Frequency (RF) systems. For example, VLC overcomes the limited RF spectrum resources for mobile users, even though its application demands an effective mechanism to handover among the different devices, in order to keep the connectivity consistent. In this paper, a new handover mechanism is introduced for mobile VLC nodes, based on a real time evaluation of the Interference-to-Noise Ratio (INR). This mechanism is coupled with four adaptive modulation schemes to further enhance the data rate. The communication system is evaluated at 0.15 mps and 0.3 mps velocities for different parameters i.e., handover rate, delivered data per handover and handover delay ratio, through an extensive simulated campaign. An experimental validation carried out through software-defined approach, considering a small-scale scenario and low power Light Emitting Diodes (LEDs). A perfect results alignment between simulation and measurement show how suggested INR-based mechanism overcomes classical SNR-based handover for all performance parameters evaluated in this study.