Abstract. Newcastle disease (Paramyxoviridae) is a highly infectious virus shed in the faeces of infected birds. Non-biting Muscid flies characteristically visit manure and decaying organic material to feed and oviposit, and may contribute to disease transmission. The housefly, Musca domestica (Linnaeus, 1758) (Diptera: Muscidae), has been implicated as a mechanical vector of numerous pathogens. In this study 2000 aerial net-captured houseflies were examined for their ability to harbour Newcastle disease virus (NDV). In an adjacent study, laboratory-reared flies were experimentally exposed to NDV La Sota strain. The virus was detected in the dissected gastrointestinal tract of laboratory-exposed flies for up to 72 h post-exposure, whereas the untreated control flies were negative.

Chlamydiosis is one of the most important infectious diseases of birds. In this study, 253 clinical samples were taken from 27 bird species belonging to seven orders. Thirty-two (12.6%) samples were positive for Chlamydia psittaci major outer membrane gene (ompA) DNA by a nested polymerase chain reaction (PCR). Twelve nested PCR-positive specimens were typed by ompA gene-based PCR-restricted fragment length polymorphism, using CTU/CTL primers and AluI restriction enzyme.

Escherichia coli is one of the most important bacterial avian pathogens and a common inhabitant of the gastrointestinal tract of animals. Most pathogenic E. coli can not be differentiated biochemically or by classic microbiologic methods. Molecular typing methods, particularly PCR, facilitated epidemiological and ecological studies of bacteria. Here we describe the application of a random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) for molecular genetic differentiation of E. coli isolates in Iran. In this study 58 E. coli isolates including 4 standard strains, 3 food originated isolates, 33 avian isolates, 8 isolates form diarrheic calves and 10 isolates from unweaned diarrheic lambs were analyzed by RAPD-PCR using primer 1247(5 / -AAG AGC CCG T-3 / ). The RAPD analysis showed that these isolates could be grouped into 33 RAPD types and avian isolates were discriminated into 29 genotypes. It was shown that the primer could not differentiate E. coli isolated from lambs. Discriminatory index for entire isolates was 0.912 and for avian isolates was 0.990. We concluded that RAPD-PCR can be used as a method for molecular differentiation of E. coli isolates.

High mortalities in 17 canary flocks from different regions of Tehran, Iran, were reported. Necropsy and histopathologic examination revealed necrotic hepatitis and overall congestive septicaemia in carcasses. Salmonella enterica was isolated from 34 examined samples, two samples from each flock, including visceral organs of carcasses and droppings of live diseased birds. All isolates were typed as Salmonella enterica serovar Typhimurium by conventional serotyping. Antibiotic resistance profiling using 33 antibiotics and random amplification of polymorphic DNA differentiation by three primers were performed and showed an identical clonal relationship between these isolates and S. Typhimurium isolated from a sample of feedstuffs. Changing the feed ingredients along with antibiotic therapy via the drinking water by enrofloxacin solution controlled the outbreaks, and mortalities ceased. The zoonotic nature of S. Typhimurium and close contact of bird owners with pet birds in the home environment made the case significant in relation to public health.

Coccidian parasites, especially Isospora, are prevalent parasites in Passeriformes. Isosporan oocysts from common mynahs (Acridotheres tristis) are incompletely described. Detailed knowledge on biology, prevalence, pathogenesis and treatment of avian isosporiasis is scant. In this study, isosporan oocysts isolated from common mynahs were morphologically and molecularly characterized. The medication efficiencies of diclazuril and sulfadiazine-trimethoprim in isosporiasis in naturally infected mynahs were evaluated. Isosporan oocysts from common mynahs were described morphologically by microscopic imaging. The 18S rRNA and COI genes were amplified using PCR and the resultant products were sequenced and analysed phylogenetically. To evaluate the efficiencies of diclazuril and sulfadiazine-trimethoprim, two experimental treatment groups and a null control were assigned. General health status, weight and oocysts per gram of faeces were evaluated. Oocysts from all birds contained isosporan oocysts that were morphologically and dimensionally similar (P < 0.05). The oocysts were spherical; with no oocyst residuum, micropyle or polar granules. At both loci, phylogenetic analyses placed the Isospora isolate in the same clade with Isospora spp. from other Passeriformes. Both of the anticoccidials were well tolerated by the birds, a rapid reduction in oocyst excretion was noted at the commencement of treatment and 72 h after drug administration, oocyst excretion zeroed in all treated birds. Based on morphological and molecular data, this isolate does not resemble any previously described isosporas, hence Isospora tristum n. sp. is proposed for the current species. Both evaluated anticoccidials seemed to be efficient in reduction of oocyst production and can be recommended for the treatment of mynah isosporiasis.