Domestic Bird Species Research Articles

Sperm Cryopreservation in Canaries to Protect Endangered Songbird Species: Comparison of Different Cryoprotectants.

Sperm cryopreservation is a rather complex process that needs to be adapted to wild and domestic bird species to ensure adequate efficiency. This study aimed to determine the usability of different cryoprotectants in the cryopreservation of Gloster canary sperm. For this purpose, sperm samples were collected from 12 2-year-old male Gloster canaries three times a week using cloacal massage for 4 weeks. After individual evaluation, sperm samples from the canaries were combined. Mixed sperm were divided into two groups in the study. Overall, 8% dimethyl sulfoxide (DMSO) and ethylene glycol (EG) were used as cryoprotectants. Sperm samples were drawn into straws after adding Dulbecco's Modified Eagle Medium (DMEM) extender with high glucose ratio and two different cryoprotectants in a 1:1 ratio and frozen to -80°C with liquid nitrogen vapour and then stored in liquid nitrogen at -196°C. Frozen-thawed semen samples were evaluated regarding motility, vitality, plasma membrane integrity (hypoosmotic swelling test [HOST]), density and abnormal spermatozoa rate. The highest motility value after freezing and thawing was determined in the EG group with 31.667%±4.773%. In addition, vitality, plasma membrane integrity and normal sperm morphology were statistically significantly higher in the EG-frozen group, whereas head and tail abnormality was low (p<0.05). This study determined that a DMEM extender containing 8% EG was more advantageous than a DMEM containing DMSO regarding spermatological parameters and could be used for long-term storage of canary sperm.

Genetic features of avian influenza (A/H5N8) clade 2.3.4.4b isolated from quail in Egypt

Several genotypes of the highly pathogenic avian influenza (HPAI) virus H5N8 subtype within clade 2.3.4.4b continue to circulate in different species of domestic birds across Egypt. It is believed that quail contribute to virus replication and adaptation to other gallinaceous poultry species and humans. This study provides genetic characterization of the full genome of HPAI H5N8 isolated from quail in Egypt. The virus was isolated from a commercial quail farm associated with respiratory signs. To characterize the genetic features of the detected virus, gene sequencing via Sanger technology and phylogenetic analysis were performed. The results revealed high nucleotide identity with the HPAI H5N8 virus from Egypt, which has multiple basic amino acid motifs PLREKRRKR/GLF at the hemagglutinin (HA) cleavage site. Phylogenetic analysis of the eight gene segments revealed that the quail isolate is grouped with HPAI H5N8 viruses of clade 2.3.4.4b and closely related to the most recent circulating H5N8 viruses in Egypt. Whole-genome characterization revealed amino acid preferences for avian receptors with few mutations, indicating their affinity for human-like receptors and increased virulence in mammals, such as S123P, S133A, T156A and A263T in the HA gene. In addition, the sequencing results revealed a lack of markers associated with influenza antiviral resistance in the neuraminidase and matrix-2 coding proteins. The results of the present study support the spread of HPAIV H5N8 to species other than chickens in Egypt. Therefore, continuous surveillance of AIV in different bird species in Egypt followed by full genomic characterization is needed for better virus control and prevention.

Testing Mini-FLOTAC for the Monitorization of Gastrointestinal Parasitic Infections in Birds Kept at Four Iberian Zoological Institutions

Birds kept in zoological institutions are highly exposed to gastrointestinal (GI) parasitism caused by coccidia and nematodes. The current research aimed to characterize the avian GI parasitic fauna in several zoological collections in Portugal and Spain. During the full year of 2022, a total of 120 fecal samples were collected from four zoological institutions: Lisbon Zoo, Olivais Pedagogical Farm, and Avian Biodiversity Center (Lisbon, Portugal), and Avifauna park (Lugo, Spain). Analysis was conducted in domestic bird species (autochthonous and exotic poultry breeds), and 18 different exotic bird species like Galliformes (peacock, pheasant), Anseriformes (duck), Psittaciformes (parrot, macaw, cockatiel, parakeet, cockatoo), Coraciiformes (motmot), Charadriiformes (avocet), Strigiformes (owl), Phoenicopteriformes (flamingo), Struthioniformes (ostrich), Rheiformes (rhea), and Casuariiformes (emu, cassowary). Feces were processed using Mini-FLOTAC (MF), to identify parasitic forms and quantify their shedding (oocysts or eggs per gram of feces). Moreover, 15 fecal samples from pheasants were also processed using the McMaster method (McM), to compare the parasite shedding and frequencies between techniques. MF implementation allowed identification of coccidia infections in all bird collections. Also, peacocks of the Lisbon Zoo tested positive for Trichostrongylus tenuis and Strongyloides pavonis, and the exotic birds from Avifauna park were also positive for several nematode species, with Ascaridia sp., Capillaria sp., Strongyloides sp., and Syngamus trachea eggs being detected in pheasants’ feces. Moreover, the analysis of pheasants’ feces with MF detected prevalences of 33% for coccidia oocysts, and 47% for Capillaria sp. and Ascaridia sp. eggs, while McM detected prevalences of 13%, 27%, and 40% for the respective parasite taxa, with no differences being observed between methods (p = 0.39, p = 0.45, and p = 0.50, respectively). This research provided more scientific support regarding the importance of using Mini-FLOTAC in routine parasitological diagnosis in birds kept at zoological institutions.

A(H5N1) Avian Influenza Virus: A New Pandemic Threat on the Horizon?

The present Editorial deals with the highly pathogenic avian influenza (HPAI) virus A(H5N1), whose clade 2.3.4.4b has been identified in several domestic and wild bird and mammalian species, both terrestrial and aquatic, with mass mortality outbreaks also affecting South American sea lions. Within this fast evolving scenario, the progressively and consistently expanding range of virus-susceptible host species alongside the prominent viral neurotropism and neuropathogenicity are a matter of concern, with A(H5N1) virus having additionally spread among USA cattle, which may also shed it through their milk. Although it is not happening at the moment, the possibility A(H5N1) virus may sooner or later become easily transmissible between people appears to be largely plausible. A collaborative, intersectorial and multidisciplinary approach, based upon the "One Health" concept/principle is strongly needed in order to properly counteract the global menace brought about by the HPAI A(H5N1) virus, thereby taking inspiration from the lessons learned during the COVID-19 pandemic.

Spillover of Newcastle disease virus to Himalayan Griffon vulture: a possible food-based transmission.

The Newcastle disease virus (NDV) affects wild and domesticated bird species, including commercial poultry. Although the diversity of NDV in domestic chickens is well documented, limited information is available about Newcastle disease (ND) outbreaks in other bird species. We report an annotated sequence of NDV/Vulture/Borjuri/01/22, an avirulent strain of NDV reported from Borjuri, Northeast India, in Himalayan Griffon vulture. The complete genome is 15,186 bases long with a fusion protein (F) cleavage site 112GRQGR↓L117. The phylogenetic analysis based on the F protein gene and the whole genome sequence revealed that the isolate from the vulture belongs to genotype II, sharing significant homology with vaccine strain LaSota. The study highlights the possible spillover of the virus from domestic to wild species through the food chain.

A highly pathogenic avian influenza virus H5N1 clade 2.3.4.4 detected in Samara Oblast, Russian Federation.

Avian influenza (AI) is a global problem impacting birds and mammals, causing economic losses in commercial poultry farms and backyard settings. In 2022, over 8,500 AI cases were reported worldwide, with the H5 subtype being responsible for many outbreaks in wild and domestic birds. In the territory of the Russian Federation, outbreaks of AI have been massively reported since 2020, both among domestic bird species and wild bird species. Wild migratory birds often serve as natural reservoirs for AI viruses, and interactions between bird species can lead to the emergence of new, highly pathogenic variants through genetic recombination between strains. In order to combat the widespread outbreaks of the disease and potential risks of further spread in 2021, monitoring studies were conducted in the Samara Oblast, the southeastern region of European Russian Federation. These studies aimed to diagnose and characterize circulating AI virus variants among wild migratory birds during waterfowl hunting in areas of mass nesting. Among the 98 shot birds, a highly pathogenic A/H5N1 AI virus was detected in a Eurasian Teal from the Bolshechernigovsky district. It was classified into clade 2.3.4.4 based on the cleavage site structure of HA. Phylogenetic analysis showed a high relatedness of the identified strain in the Samara Oblast with field isolates from Russia, Nigeria, Bangladesh, and Benin. The article emphasizes the importance of monitoring AI virus spread in both wild and poultry, highlighting the need for timely information exchange to assess risks. Further comprehensive studies are necessary to understand virus dissemination pathways.

New data on the chewing lice (Psocodea: Phthiraptera) of domestic and wild birds in Türkiye

This study was carried out to detect the chewing lice species of domestic and wild birds in Türkiye, between the years of 2014–2021, and whether there is a correlation between the number of bird species and individuals and the prevalence, mean intensity and species of chewing lice. For this purpose, 206 bird samples as injured, or found dead on roads and gardens between these dates, in seventeen orders were examined for chewing lice. Of the 206 wild birds examined, 135 (65.53%) were infested with lice. A total of 73, of which 34 were Amblyceran and 39 were Ischnoceran chewing lice species, were identified. The genera Acidoproctus, Aegypoecus, Bonomiella, Esthiopterum, Gruimenopon, Heleonomus, Neopsittaconirmus, and the species Acidoproctus moschatae, Aegypoecus spp. (nymph), Amyrsidea minuta, Ardeicola maculatus, Ardeicola stellaris, Bonomiella columbae, Brueelia tasniemae, Colpocephalum nigrae, Colpocephalum percnopteri, Colpocephalum zerafae, Ciconiphilus pectiniventris, Esthiopterum gruis, Goniodes pavonis, Gruimenopon longum, Guimaraesiella amsel, Heleonomus macilentus, Kurodaia cryptostigmata, Kurodaia subpachygaster, Menacanthus kaddoui, Myrsidea isostoma, Neophilopterus tricolor, Neopsittaconirmus spp. (nymph), Pseudomenopon dolium, and Rallicola minutus are reported here for the first time. Based on statistical analysis, the host species and individual numbers are correlated with lice species numbers. It was also found that the host individual number is correlated with the mean intensity of the lice. Our results indicate that a large number of samples belonging to different host species are important in terms of data reliabilty.

Optical luminescent properties of eggs

Relevance. Optical photoluminescent properties of poultry eggs can serve as indicators of their quality both for incubation processes and for food technology processes. At the initial stage, it is important to evaluate the spectral characteristics of excitation and luminescence, as well as the parameters of table and incubation eggs of different quality and with different shell color.Methods. Chicken eggs of Chinese silk and Hysex brown crosses, as well as samples of duck, goose and quail eggs were used for research. The measurements were carried out on a diffraction spectrofluorimeter “Fluorat02-Panorama” with built-in software “Panorama Pro”. The obtained spectral characteristics were used to calculate the energy (integral absorption capacity and luminescence flux, spectrum energy) and statistical parameters (expectation, variance, asymmetry, kurtosis), as well as the Stokes shift.Results. Photoluminescent properties of poultry eggs are manifested in the ultraviolet region of the spectrum. Qualitatively, the spectra of different species of domestic birds are similar with a slight difference in the Stokes shift. For fertilized chicken eggs, the photoluminescence flux is 2.7 times greater than that of unfertilized eggs, while the spread of values for unfertilized eggs is 5.6 times less. Spectrum parameters such as asymmetry and kurtosis differ significantly for the luminescence of dark and light-shell chicken eggs. For table eggs, the integral energy parameters are 2.8–3.1 times greater than those of incubation eggs.

Influence of Tempetature on Viability and Deveplopment of Heterakis gallinarum (Nematoda, Heterakidae) Eggs

Pinworms of the genus Heterakis Dujardin, 1845 parasitize a wide range of hosts, including a number of species of domestic and wild birds. These nematodes are ecologically adapted to the climatic conditions of many geographical zones, which contributes to their widespread distribution. The aim of the work was to investigate the influence of different temperature regimes at laboratory conditions on the growth, development and viability of eggs isolated from the gonads of female nematodes Heterakis gallinarum Schrank, 1788. The conducted studies established that, depending on the cultivation temperature, nematode eggs developed from 6 to 56 days, and their survival rate was from 67.7 to 83.7 %. The temperature of 25 °С was the most favourable for the development of H. gallinarum eggs, the development lasted 12 days and the highest number of eggs with motile infective larvae was formed (83.7 %). It was found that the period of egg development in cultures gradually decreased with increasing temperature: it was 56 days at 15 °C, 18 days at 20 °C, 12 days at 25 °C and 6 days at 30 °C. The survival rate of H. gallinarum eggs gradually increased with increasing temperature in regimes of 15 °С, 20 °С and 25 °С to 67.7 %, 80.7 % and 83.7 %, respectively. At a temperature of 30 °C, egg survival decreased slightly to 78.7 %. It was found that the development of H. gallinarum eggs from the zygote stage to the formation of motile infective larvae, depending on the temperature regime of cultivation, is accompanied by a decrease in egg length by 4.9–5.4 %, an increase in egg width by 4.1–7.6 % and a thinning of the shell by 9.5–28.6 %. Under different temperature regimes, the morphometric parameters of eggs during their development differ in terms of their length, width and shell thickness.

Snapshot of the Phylogenetic Relationships among Avian Poxviruses Circulating in Portugal between 2017 and 2023.

Avipoxvirus (APV), a linear dsDNA virus belonging to the subfamily Chordopoxvirinae of the family Poxviridae, infects more than 278 species of domestic and wild birds. It is responsible for causing avian pox disease, characterized by its cutaneous and diphtheric forms. With a high transmission capacity, it can cause high economic losses and damage to the ecosystem. Several diagnostic methods are available, and bird vaccination can be an effective preventive measure. Ten APV-positive samples were analyzed to update the molecular characterization and phylogenetic analysis of viruses isolated in Portugal between 2017 and 2023. A P4b gene fragment was amplified using a PCR, and the nucleotide sequence of the amplicons was determined using Sanger sequencing. The sequences obtained were aligned using ClustalW, and a maximum likelihood phylogenetic tree was constructed. With this study, it was possible to verify that the analyzed sequences are distributed in subclades A1, A2, B1, and B3. Since some of them are quite similar to others from different countries and obtained in different years, it is possible to conclude that there have been several viral introductions in Portugal. Finally, it was possible to successfully update the data on Avipoxviruses in Portugal.

Current situation of avian influenza due to the highly pathogenic subtype A/H5N1 in Mexico. Proceeding of The First International Avian Influenza Summit, University of Arkansas- October 16-17, 2023"

The first report of news of an epizootic of Avian Influenza (AI) occurred in the neighborhoods of the city of Turín, Italy, in family poultry farms in 1878, which resulted in high mortality rates. The infection spread to the north and west of Europe, ending a year later in England. It was the distinguished Italian veterinarian Edoardo Bellarmino Perocitto (1847-1936), who created a detailed clinical, pathological, and epidemiological description of this viral infection of birds. In 2014, a virus emerged that has since commanded the attention of researchers. This virus was isolated from a domestic goose in Guangdong, China, and was classified as A/Goose/Guandong/1/14. This line sparked a strong focus among avian pathologists because, since its appearance, it has caused death in domestic and wild birds and has spread to more than 76 countries in Asia, Europe, North America, and South America. It is well known that migratory aquatic birds are the main actors in the ecology of Orthomyxoviruses of Avian Influenza. IA is caused by an Orthomyxovirus whose envelope contains surface glycoproteins: Hemagglutinin (HA) and Neuraminidase (NA). Types A, B, and C are isolated from animals. Types B and C have been isolated from man. Type A viruses are capable of infecting birds, humans, horses, and other mammals. The incubation period of AI Orthomyxoviruses is one to seven days and clinically causes a severe congestive-hemorrhagic respiratory, intestinal, and neurological condition, with mortality rates of 90 to 95\% and mortality rates of 95 to 100\%. Both Avian Influenza and Human Influenza have a seasonal presentation during the autumn and winter months of each year. Currently, the AI viruses H5N1 and H7N9 are zoonotic. Asian strain subtypes with greater impact on the health of people and their origin have occurred due to the spread between different species of wild birds, domestic and productive birds, and the people who take care of them and sell them. The global situation of Avian Influenza, a cross-border disease, continues to threaten the health of birds in practically all countries under agreement with the World Organization for Animal Health (OMSA/OIE). From 2021 to December 2022, more than 8,142 outbreaks of Highly Pathogenic Avian Influenza H5N1 appeared in 76 countries on four continents, affecting more than 120 million birds. The poultry industry in the United States of America has slaughtered more than 60 million commercial, domestic, and free-range birds (chickens, turkeys, and ducks), and wild birds between 2022-2023. This serious and worrying situation at a global level means that the World Animal Health Organization located in Paris, France, organized a meeting with all countries affected by AI in October 2022, during which it was concluded and authorized in an unprecedented decision for the first authorizing vaccination against AI in affected countries and publishing a manual “OIE Vaccination: A tool for the control of Avian Influenza.

A novel pathogenic avipoxvirus infecting oriental turtle dove (Streptopelia orientalis) in China shows a high genomic and evolutionary proximity with the pigeon avipoxviruses isolated globally.

Avipoxviruses are considered as significant viral pathogen infecting a wide range of domestic and wild bird species globally, yet the majority of avipoxviruses that infect the wild bird species remain uncharacterized and their genetic diversities remain unclear. In this study, we present a novel pathogenic avipoxvirus isolated from the cutaneous pox lesions of a wild oriental turtle dove (Streptopelia orientalis), tentatively named as turtle dovepox virus (TDPV). The avipoxvirus was isolated by using the chorioallantoic membranes of specific pathogen-free chicken embryos which showed characteristic focal pock lesions, followed by cytopathic effects in host cells infected with oriental turtle dovepox virus. An effort in sequencing the whole genome of the poxvirus using next-generation sequencing was given, and the first whole genome sequence of TDPV was obtained. The TDPV genome was 281,386 bp in length and contained 380 predicted open reading frames (ORFs). While 336 of the predicted ORFs showed homology to other characterized avipoxviruses, the other 44 ORFs were unique. Subsequent phylogenetic analyses showed that the novel TDPV shared the closest genetic evolutionary linkage with the avipoxviruses isolated from pigeon in South Africa and India, of which the TDPV genome had the highest sequence similarity (92.5%) with South African pigeonpox virus (FeP2). In conclusion, the sequenced TDPV is significantly different from any other avipoxviruses isolated from avian or other natural host species considering genomic architecture and observed sequence similarity index. Thus, it likely should be considered a separate species. IMPORTANCE Over the past few decades, avipoxviruses have been found in a number of wild bird species including the oriental turtle dove. However, there is no whole genome sequence information on avipoxviruses isolated from oriental turtle dove, leaving us unclear about the evolutionary linkage of avipoxviruses in oriental turtle dove and other wild bird species. Thus, we believe that our study makes a significant contribution because it is the first report of the whole genome sequence of TDPV isolated from a wild oriental turtle dove, which enriches the genomic information of the genus Avipoxvirus, furthermore, contributes to tracking the genetic evolution of avipoxviruses-infected oriental turtle dove species.

Nosological profile and classification of infectious diseases of farm animals in the territory of the Pepublic of Sakha (Yakutia)

The results of the classification of infectious diseases of farm animals spread on the territory of the Republic of Sakha (Yakutia) for the period 2001-2021 are presented. It was found that there were 42 nosological units of animal diseases involved in the epizootic process on the territory of Yakutia. Infections in cattle are caused by 18 types of pathogens, horses - 12, reindeer - 4, pigs - 10, birds - 11, small ruminants - 3, fur-bearing animals - 7, other types of animals - 9. According to the OIE classification, 10 nosoforms of diseases are common in Yakutia: rabies, brucellosis, viral hemorrhagic septicemia, equine infectious anemia, avian infectious bronchitis, infectious bovine rhinotracheitis, paratuberculosis, pasteurellosis and tuberculosis. Diseases not on the OIE list, including Marek’s disease, swine dysentery, colibacillosis, parvoviral enteritis, salmonellosis, diamond-skin disease, blackleg were registered. A number of nosoforms common in Yakutia belong to particularly dangerous diseases for which restrictive measures (quarantine) may be imposed. These include actinomycosis, rabies, brucellosis, infectious equine anemia, avian infectious bronchitis, infectious bovine rhinotracheitis, bovine leukosis, leptospirosis, paratuberculosis, diamond-skin disease, tuberculosis and canine distemper virus. A number of diseases (Marek’s disease, carnivorous infectious hepatitis, bovine leukosis, horse strangles, avian ornithosis, egg drop syndrome, diamond-skin disease, and blackleg) are peculiar to only one species of animals. Many infections are characterized by the persistence of the pathogen in different species of farm and small domestic animals, birds and wildlife, which determines the interspecies degree of epizootic danger of these infections. Infections of bacterial etiology (bacterioses) prevail in Yakutia with 21 nosoforms. Viral diseases (viroses) are represented by 15 nosoforms, mycoplasmosis and chlamydia - one each. The most numerous infections are those with the main alimentary, or fecal-oral, route (22 diseases). Ten infections, including infectious atrophic rhinitis, infectious bovine rhinotracheitis, distemper, are classified as airborne or respiratory (major) pathogen transmission. Transmissive carry-over (by vectors) is characterized by actinomycosis and infectious equine anemia; through the outer covers (without the participation of vectors) - 5 diseases, including balanoposthitis and rabies. The majority of the infections are characterized by one or more additional mechanisms of transmission (rabies, Marek’s disease, bovine leukemia, diamond-skin disease, etc.) in addition to the main mechanism of transmission of the pathogen. According to the source of the causative agent for all diseases (ktenonoses) they are domestic animals, but for such infections as rabies, Marek’s disease, viral hemorrhagic septicemia, leptospirosis and others, along with domestic animals, wild animals are an additional source (ktenotherionoses). In terms of susceptibility, most infections (30) belong to zoonoses peculiar only to animals; the remaining 12 belong to the more dangerous zooanthroponoses common to animals and humans.

Human death due to H5N1 amid the COVID-19 pandemic and Mpox outbreak: A call for action.

Human death due to H5N1 amid the COVID-19 pandemic and Mpox outbreak: A call for action.

Сезонные аспекты питания Поволжской популяции солнечных орлов в гнездовой период

Сезонные аспекты питания Поволжской популяции солнечных орлов в гнездовой период

Значение птиц на золотоордынских сельских поселениях Нижнего Поволжья (на примере Багаевского селища)

Objective: The purpose of this work is a comprehensive analysis of bird remains from the archaeozoological collection of the Bagaevka settlement, including species, quantitative data, size-age composition, and an interpretation of the results obtained taking into account archaeological data. The importance of birds is considered, using the example of rural settlements of the Uvek site region and the Golden Horde city Ukek itself. Research materials: The article presents a study of the bird remains from the Bagaevka settlement (trench I) – a large settlement of a region centered on the Golden Horde city Ukek from the second half of the 13th century through the 14th century. As a comparison of the consumption and importance of birds in the life of the people of the city and rural settlement of the Golden Horde period of the Saratov Volga region, we present the results of a study of a collection of bird remains from the excavations of the Uvek site. Results and novelty of the research: This study is the first comprehensive analysis of bird remains and their interpretation for this area in the Golden Horde period. In the archaeozoological collection of the Bagaevka settlement, 24 species have been identified: 3 species of domestic birds and 21 species of wild birds. In a quantitative ratio, bones of domestic chickens prevail – 70.1% of all found bird bones. Among the remains of wild species, the largest number of bones belonged to the black grouse. Interesting are the finds of the remains of birds of prey, Accipitriformes, and the presence of remains from synanthropic species. The study of the collections revealed a high diversity of bird species and the versatility of their use: food; breeding of domestic species for meat and eggs; hunting with birds of prey; and the use of some species of wild birds (owls) as sacred animals.

Seroprevalence and risk factors associated with Newcastle disease in backyard chickens in West Kordofan State, Sudan.

Newcastle disease (ND), a major constraint to poultry production worldwide, is a highly contagious disease of many species of domestic, exotic, and wild birds caused by ND virus (NDV). Epidemiological studies are lacking regarding ND in village chickens, including the traditional and intensive production systems used in Sudan. However, it is necessary to develop appropriate strategies to control the disease. Therefore, this study aimed to estimate the flock- and bird-level seroprevalence of NDV in backyard chickens in West Kordofan State, Sudan, and to identify the risk factors associated with ND in the study area. The seroprevalence of the circulating NDV and bird-level risk factors associated with ND was determined in backyard chickens from March to October 2017, in six villages (Alnowara, Alleait, Geibaish, Baiad, Sougoh, and Alnuhoud) in the Geibaish and Elnuhoud localities of West Kordofan State. Using the hemagglutination-inhibition test, the bird- and flock-level seroprevalences of antibodies to NDV were estimated as 20.6% (78/378) and 45% (18/40), respectively. Bird-level NDV seropositivity in backyard chickens was significantly associated with the reason for raising chickens, type of housing, contact with neighboring poultry, contact with wild birds, and chicken mortality caused by infectious diseases (p ≤ 0.05). This study indicated that NDV is circulating in backyard chickens and may act as a potential source of infection for other birds and thus persistence of ND among local traditionally managed chickens in the areas of West Kordofan State. Risk factors contributing to ND occurrence are important for designing appropriate prevention and control strategies.

Pathogenicity and transmissibility studies on live attenuated duck enteritis virus vaccine in non-target species.

In the second half of 2021, a highly pathogenic case occurred in a mixed chicken and duck family farm in Guangdong, China. After the duck flocks were immunized with live attenuated duck enteritis virus vaccine (live attenuated DEV vaccine), the chickens of the same farm showed clinical symptoms similar to duck enteritis, such as pericardial effusion, hepatic hemorrhagic spots, kidney enlargement, and intestinal bleeding, with mass mortality. The infection model of target animal tested, as well as the non-target species, was established according to the risk of live attenuated DEV vaccine and transmission in chickens. Live attenuated DEV vaccine was initially replicated in host animals, released the virus, and effectively colonized in the common environment, according to birds challenged experiments. There was evidence to suggest the mode of transmission of duck enteritis virus, and horizontal transmission is the main route of DEV transmission. In addition, high levels of virus titer were detected in chicken embryos and different tissues of SPF chickens. Different degrees of pathological damage occurred in the tissue of chickens. After the SPF chickens were inoculated with live attenuated DEV vaccine, different degrees of virulence were exhibited, pointing to a potential risk to other domestic bird species.

Epidemiology and molecular characterization of avian influenza virus in backyard poultry of Chattogram, Bangladesh.

Ducks, the natural reservoir of avian influenza virus (AIV), act as reassortment vessels for HPAI and low pathogenic avian influenza (LPAI) virus for domestic and wild bird species. In Bangladesh, earlier research was mainly focused on AIV in commercial poultry and live bird markets, where there is scanty literature reported on AIV in apparently healthy backyard poultry at the household level. The present cross-sectional study was carried out to reveal the genomic epidemiology of AIV of backyard poultry in coastal (Anowara) and plain land (Rangunia) areas of Bangladesh. We randomly selected a total of 292 households' poultry (having both chicken and duck) for sampling. We administered structured pre-tested questionnaires to farmers through direct interviews. We tested cloacal samples from birds for the matrix gene (M gene) followed by H5 and H9 subtypes using real-time reverse transcriptase-polymerase chain reaction (rRT-PCR). All AIV-positive samples were subjected to four-gene segment sequencing (M, PB1, HA, and NA gene). We found that the prevalence of AIV RNA at the household level was 6.2% (n=18; N=292), whereas duck and chicken prevalence was 3.6% and 3.2%, respectively. Prevalence varied with season, ranging from 3.1% in the summer to 8.2% in the winter. The prevalence of subtypes H5 and H9 in backyard poultry was 2.7% and 3.3%, respectively. The phylogenetic analysis of M, HA, NA, and PB1 genes revealed intra-genomic similarity, and they are closely related to previously reported AIV strains in Bangladesh and Southeast Asia. The findings indicate that H5 and H9 subtypes of AIV are circulating in the backyard poultry with or without clinical symptoms. Moreover, we revealed the circulation of 2.3.2.1a (new) clade among the chicken and duck population without occurring outbreak which might be due to vaccination. In addition to routine surveillance, molecular epidemiology of AIV will assist to gain a clear understanding of the genomic evolution of the AIV virus in the backyard poultry rearing system, thereby facilitating the implementation of effective preventive measures to control infection and prevent the potential spillover to humans.

First isolation of influenza a subtype H5N8 in ostrich: pathological and genetic characterization

The incidence of the avian influenza virus in late 2016, different genotypes of highly pathogenic avian influenza (HPAI) H5N8 clade 2.3.4.4b have been reported among different domestic and wild bird species. The virus became endemic in the poultry population, causing a considerable economic loss for the poultry industry. This study screened 5 ostrich farms suffering from respiratory signs and mortality rate of the avian influenza virus. A flock of 60-day-old ostriches with a mortality of 90% suffered from depression, loss of appetite, dropped production, and oculo-nasal discharges, with bleeding from natural orifices as a vent. This flock was found positive for avian influenza virus and subtypes as HPAI H5N8 virus. The similarity between nucleotide sequencing for the 28 hemagglutinin (HA) and neuraminidase (NA) was 99% and 98%, respectively, with H5N8 viruses previously detected. The PB2 encoding protein harbor a unique substitution in mammalian marker 627A, which has not been recorded before in previously sequenced H5N8 viruses. Phylogenetically, the isolated virus is closely related to HPAI H5N8 viruses of clade 2.3.4.4b. The detection of the HPAI H5N8 virus in ostrich is highly the need for continuous epidemiological and molecular monitoring of influenza virus spread in other bird species, not only chickens. Ostrich should be included in the annual SunAlliance, for the detection of avian influenza.