BACKGROUND: Interferon regulatory factors (IRFs) are a family of transcription factors with important functions in immunity. The genomes of most vertebrates encode ten IRF genes. IRF3 and IRF9 have key roles in interferon (IFN) induction and signaling. Most of our knowledge about the IFN pathways originates from the study of the mammalian IFN system, and the description of the corresponding avian components is not as complete. Both IRF3 and IRF9 were considered missing from the chicken genome and from the genomes of other avian species. RESULTS: Here we describe multiple avian IRF3 and IRF9 genes, all with difficult GC-rich sequence context that prevented their earlier characterization. IRF3 orthologs are narrowly distributed and are present in the avian infraclass Palaeognathae. In contrast, IRF9 orthologs were found in most avian species, with the exception of the order Galliformes. In about half of the avian orders, IRF9 was located in noncanonical chromosomal positions, indicating past translocations. Phylogenetic analysis confirmed the correct orthology of all newly described IRFs. We further performed experiments using duck IRF9, confirming its role in the IFN pathway. IRF9 knockout in duck fibroblasts decreases the induction of IFN-stimulated genes (ISGs). Full induction of ISGs in duck cells requires both an intact IRF9 and a canonical IFN-stimulated response element. Lastly, intact IRF9 is needed for IFN-mediated protection of duck cells against the vesicular stomatitis virus-induced cytopathicity. CONCLUSIONS: The identification of avian IRFs fills an important gap in our understanding of avian immunology and brings new questions related to the evolution of the IRF family.
- Keywords
- Avian genome, Gene loss, Interferon regulatory factors, Interferon signaling,
- MeSH
- Phylogeny MeSH
- Interferon Regulatory Factors * genetics metabolism MeSH
- Interferon Regulatory Factor-3 * genetics metabolism MeSH
- Interferon-Stimulated Gene Factor 3, gamma Subunit * genetics metabolism MeSH
- Ducks genetics MeSH
- Chickens genetics MeSH
- Avian Proteins * genetics metabolism MeSH
- Birds * genetics MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Interferon Regulatory Factors * MeSH
- Interferon Regulatory Factor-3 * MeSH
- Interferon-Stimulated Gene Factor 3, gamma Subunit * MeSH
- Avian Proteins * MeSH
BACKGROUND: Previous studies on the tick infestation of birds in the Carpathian Basin focused on songbirds (Passeriformes). Thus, the primary aim of the present work was to extend the scope of previous studies, i.e. to include aquatic (water-associated) bird species in a similar context, especially considering that these birds are usually long-distance migrants. METHODS: Between March 2021 and August 2023, 11,919 birds representing 126 species were checked for the presence of ticks. From 352 birds belonging to 40 species, 905 ixodid ticks were collected. Tick species were identified morphologically and/or molecularly. RESULTS: Ticks from avian hosts belonged to seven species: Ixodes ricinus (n = 448), I. frontalis (n = 31), I. festai (n = 2), I. arboricola (n = 36), I. lividus (n = 4), Haemaphysalis concinna (n = 382) and Dermacentor reticulatus (n = 2). Nymphs of I. ricinus occurred with a single activity peak around March-May, whereas its larvae typically infested birds in May, June or July. By contrast, H. concinna usually had its activity maximum during the summer (nymphs in June-July, larvae later in July-August). Interestingly, two ornithophilic species, I. frontalis and I. arboricola, were most active around winter months (between October and April). A significantly lower ratio of aquatic birds was found tick-infested than songbirds. Several new tick-host associations were revealed, including I. ricinus from Greylag Goose (Anser anser) and D. reticulatus from Great Egret (Ardea alba) and Sedge Warbler (Acrocephalus schoenobaenus). Ticks were collected for the first time in Europe from two species of predatory birds as well as from Little Bittern (Ixobrychus minutus). Bird species typically inhabiting reedbeds were most frequently infested with H. concinna, and most ticks localized at their throat, as opposed to forest-dwelling avian hosts, on which I. ricinus predominated and ticks were more evenly distributed. CONCLUSIONS: In the evaluated region, aquatic birds appear to be less important in tick dispersal than songbirds. However, newly revealed tick-host associations in this category attest to their hitherto neglected contribution. The results suggest that the habitat type will have significant impact not only on the species composition but also on the feeding location of ticks on birds.
- Keywords
- Accipitriformes, Ixodidae, Passeriformes, Pelecaniformes,
- MeSH
- Ecosystem MeSH
- Geese MeSH
- Tick Infestations * epidemiology veterinary MeSH
- Ixodidae * MeSH
- Ixodes * MeSH
- Larva MeSH
- Nymph MeSH
- Passeriformes * MeSH
- Songbirds * MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Taxonomic and nomenclatorial revision of the Neotropical tiger beetle genus Phaeoxantha Chaudoir, 1850 (originally Megacephala Latreille, 1802) is presented. Ammosia Westwood, 1852 (with type species Megacephala bifasciata) is confirmed as a junior synonym of Phaeoxantha. The results by Naviaux (2008), who rectified commonly confused taxonomy and nomenclature of Phaeoxantha nocturna (Dejean, 1831) and P. laminata (Perty, 1830) versus P. limata, based on Megacephala limata Perty, 1833 which is an unjustified emendation by Perty (1833) in Perty (18301833), are confirmed the date of the unjustified emendation is newly rectified here. Megacephala laminata Perty, 1830 is confirmed as the type species of Phaeoxantha. Lectotype of Megacephala nocturna Dejean, 1831 is designated here, based on syntypes from the Dejean-Chaudoir collection in MNHN. The genus is subdivided here into two clearly differentiated subgenera: Phaeoxantha (Phaeoxantha) and Phaeoxantha (Euphaeoxantha) subgen. nov. The nominotypical subgenus is represented by Phaeoxantha laminata (Perty, 1830), P. (P.) nocturna (Dejean, 1831), P. (P.) nocturna crassipunctata ssp. nov., P. (P.) paranocturna sp. nov., P. (P.) epipleuralis W. Horn, 1923, P. (P.) tremolerasi (W. Horn, 1909), P. (P.) cruciata (Brull, 1837) and P. (P.) bifasciata (Brull, 1837). The latter, based on Megacephala bifasciata Brull, 1837, was published by Brull in order to rectify the concept of Megacephala aequinoctialis sensu auctorum, (primarily sensu Dejean 1825, 1833, 1836), which has been commonly yet incorrectly treated in literature as Phaeoxantha aequinoctialis aequinoctialis (Dejean, 1825). Although Dejean (1825) clearly characterized the same Megacephala species, his act cannot be interpreted as a valid description under Article 12 of the ICZN (1999), because he explicitly referred to the publications by Linnaeus (1763) and redescription by Fabricius (1775). Therefore, his act must be interpreted as a misidentification and subsequent usage of the name Cicindela aequinoctialis Linnaeus, 1763, which is in fact a bombardier beetle (Brachinini, Carabidae), presently known as Pheropsophus aequinoctialis (Linnaeus, 1763), misidentified by Dejean as Megacephala. In contrast, the name Megacephala bifasciata Brull, 1837 was validly published, supported by a rather appropriate illustration and preserved type specimen, being also in common use to the present day; therefore, the confused name aequinoctialis cannot be preserved and is considered an unavailable name being excluded here from Megacephalini and Cicindelidae. The new subgenus Phaeoxantha (Euphaeoxantha) subgen nov. (type species Megacephala testudinea Klug, 1834) comprises following five species: P. (E.) testudinea (Klug, 1834), P. (E.) klugii (Chaudoir, 1850), P. (E.) bucephala (W. Horn, 1909), P. (E.) wimmeri (Mandl, 1958) and P. (E.) lindemannae (Mandl, 1964). Keys to the two subgenera and to their species, descriptions or differential diagnoses and colour photographs of the habitus and of characters of available type specimens of all species of the genus, as well as the variability and characters of individual populations, are presented and their distribution discussed.
- MeSH
- Coleoptera * MeSH
- Ducks MeSH
- Animal Distribution MeSH
- Rubiaceae * MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Notocotylus cygni n. sp. is described here, taken from the intestine of the black-necked swan Cygnus melancoryphus (Molina) of Patagonia, Argentina. This new species differs from other members of the genus Notocotylus by having the genital pore anterior to the caecal bifurcation (located slightly posterior to oral sucker) and the unequal number and arrangement of ventral papillae (2-3 in the lateral rows and 10-12 in the median row). Phylogenetic analyses of the 28S and ITS1-5.8S ribosomal DNA (rRNA) sequences of the new species and other notocotylid trematodes available in GenBank indicate that N. cygni n. sp. is a sister taxon of Notocotylus fosteri Kinsella et Tkach, 2005, a trematode of the intestine of the rice rat Oryzomys palustris of Florida, United States. The new species differs from N. fosteri in the unequal number and arrangement of ventral papillae, number of uterine loops, size of the egg, definitive hosts (birds vs. mammals), and disparate environment and geographical distribution (freshwater environment in Patagonia vs. salt marsh in North America). This is the eighth species of Notocotylus reported from birds in Argentina, and the ninth species from the family Notocotylidae recorded in black-necked swans in South America.
- Keywords
- Anseriformes, Notocotylus cygni n. sp., Patagonia, Phylogenetic relationships, Trematoda,
- MeSH
- Phylogeny MeSH
- Ducks MeSH
- Rats MeSH
- Birds MeSH
- Mammals MeSH
- Trematoda * genetics MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Argentina MeSH
The objective of this study was to identify the key glutathione S-transferase (GST) isozymes involved in the detoxification of Aflatoxin B1 (AFB1) in ducks' primary hepatocytes. The full-length cDNA encoding the 10 GST isozymes (GST, GST3, GSTM3, MGST1, MGST2, MGST3, GSTK1, GSTT1, GSTO1 and GSTZ1) were isolated/synthesized from ducks' liver and cloned into the pcDNA3.1(+) vector. The results showed that pcDNA3.1(+)-GSTs plasmids were successfully transferred into the ducks' primary hepatocytes and the mRNA of the 10 GST isozymes were overexpressed by 1.9-3274.7 times. Compared to the control, 75 μg/L (IC30) or 150 μg/L (IC50) AFB1 treatment reduced the cell viability by 30.0-50.0% and increased the LDH activity by 19.8-58.2% in the ducks' primary hepatocytes. Notably, the AFB1-induced changes in cell viability and LDH activity were mitigated by overexpression of GST and GST3. Compared to the cells treated with AFB1, exo-AFB1-8,9-epoxide (AFBO)-GSH, as the major detoxified product of AFB1, was increased in the cells overexpression of GST and GST3. Moreover, the sequences, phylogenetic and domain analysis revealed that the GST and GST3 were orthologous to Meleagris gallopavo GSTA3 and GSTA4. In conclusion, this study found that the ducks' GST and GST3 were orthologous to Meleagris gallopavo GSTA3 and GSTA4, which were involved in the detoxification of AFB1 in ducks' primary hepatocytes.
- Keywords
- Aflatoxin B(1), Detoxification, Duck, Glutathione S-transferase, Hepatotoxicity,
- MeSH
- Aflatoxin B1 * MeSH
- Phylogeny MeSH
- Glutathione genetics MeSH
- Glutathione Transferase genetics MeSH
- Isoenzymes genetics MeSH
- Liver MeSH
- Ducks * MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Aflatoxin B1 * MeSH
- Glutathione MeSH
- Glutathione Transferase MeSH
- Isoenzymes MeSH
In 2021/2022, the re-emergence of highly pathogenic avian influenza (HPAI) occurred in Europe. The outbreak was seeded from two sources: resident and reintroduced viruses, which is unprecedented in the recorded history of avian influenza. The dominant subtype was H5N1, which replaced the H5N8 subtype that had predominated in previous seasons. In this study, we present a whole genome sequence and a phylogenetic analysis of 57 H5N1 HPAI and two low pathogenic avian influenza (LPAI) H5N1 strains collected in the Czech Republic during 2021/2022. Phylogenetic analysis revealed close relationships between H5N1 genomes from poultry and wild birds and secondary transmission in commercial geese. The genotyping showed considerable genetic heterogeneity among Czech H5N1 viruses, with six different HPAI genotypes, three of which were apparently unique. In addition, second-order reassortment relationships were observed with the direct involvement of co-circulating H5N1 LPAI strains. The genetic distance between Czech H5N1 HPAI and the closest LPAI segments available in the database illustrates the profound gaps in our knowledge of circulating LPAI strains. The changing dynamics of HPAI in the wild may increase the likelihood of future HPAI outbreaks and present new challenges in poultry management, biosecurity, and surveillance.
- Keywords
- H5N1, HPAI, avian influenza, highly pathogenic avian influenza, outbreak, poultry,
- MeSH
- Poultry MeSH
- Farms MeSH
- Phylogeny MeSH
- Genotype MeSH
- Geese MeSH
- Influenza in Birds * epidemiology MeSH
- Influenza A Virus, H5N1 Subtype * genetics MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic epidemiology MeSH
1. This study evaluated and compared the oxidation status of meat from conventionally-farmed, organic and wild ducks during chilled storage in air or vacuum packaging. In total, 48 carcases from each group of ducks were investigated, and 24 carcases from each type of production were stored under vacuum or in air at 3°C ± 1°C. Sample analyses were conducted after 1, 3, 6 and 9 d of storage.2. The antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl: DPPH), thiobarbituric acid reactive substances (TBARS) and free fatty acids in the breast, thigh and wing muscles were determined.3. The antioxidant capacity of meat from conventional ducks was higher than that from organic and wild ducks. The muscles of organic and wild ducks were more susceptible to secondary oxidation (particularly when stored in air) than conventionally-raised birds. The free fatty acid levels in samples of breast and thigh meat from wild ducks on the last day of storage were higher than in conventional and organic ducks.4. The results showed that the oxidation status of meat from conventional ducks was more stable during refrigerated storage than the meat of organic and wild ducks.
- Keywords
- Meat oxidation, farmed duck, organic, storage, wild,
- MeSH
- Antioxidants analysis MeSH
- Atmosphere analysis MeSH
- Ducks * MeSH
- Chickens MeSH
- Meat analysis MeSH
- Food Packaging * methods MeSH
- Vacuum MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Antioxidants MeSH
Despite their widespread distribution, only a single genotype variant of clade 2.3.4.4b H5N1 influenza viruses has been found so far in Europe. Here, we report the detection of a new highly pathogenic avian influenza H5N1 genotype in geese and ducks from a backyard farm in the Czech Republic. Phylogenetic analysis revealed that the Czech H5N1 virus retained the A/Eurasian_Wigeon/Netherlands/1/2020-like backbone with an altered PB2 segment obtained from co-circulating low-pathogenic avian influenza viruses.
Trueperella (T.) bernardiae is a well-known bacterial pathogen in infections of humans, rarely in animals. In the present study, five T. bernardiae isolates, isolated from five Peking ducks of four different farms, were identified by phenotypic properties, by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, and genotypically by sequencing the 16S ribosomal RNA (rRNA) gene, the superoxide dismutase A encoding gene sodA, and the glyceraldehyde-3-phosphate dehydrogenase encoding gene gap. In addition, the T. bernardiae isolates could be identified with a newly developed loop-mediated isothermal amplification (LAMP) assay based on the gyrase encoding housekeeping gene gyrA. All these tests clearly identified the T. bernardiae isolates to the species level. However, the detection of the specific gene gyrA with the newly designed LAMP assay appeared with a high sensitivity and specificity, and could help to identify this bacterial species in human and animal infections in future. The importance of the T. bernardiae isolates for the clinical condition of the ducks and for the problems at farm level remains unclear.
- MeSH
- Actinomycetaceae MeSH
- Arcanobacterium * genetics MeSH
- Molecular Diagnostic Techniques MeSH
- Ducks * genetics MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods MeSH
- Nucleic Acid Amplification Techniques MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Beijing MeSH
- Names of Substances
- RNA, Ribosomal, 16S MeSH
The main objective of this long-term study (1978-2016) was to find the underlying factors behind the declining trends of eider Somateria mollissima in the Baltic/Wadden Sea. Specifically, we aimed at quantifying the bottom-up effect of nutrients, through mussel stocks, on reproduction and abundance of eider, and the top-down effects caused by white-tailed eagle Haliaeetus albicilla predation. Bottom-up effects increase marine primary productivity with subsequent effects on food availability for a major mussel predator. Top-down effects may also regulate eider populations because during incubation female eiders are vulnerable to predation by eagles. Our structural equation modelling explained a large percentage of the variance in eider abundance. We conclude that the Baltic/Wadden Sea eider population was regulated directly by white-tailed sea eagle predation on incubating females and indirectly by the amount of nutrients in seawater affecting both mussel stocks and the breeding success of eiders, reflecting density dependence. These findings may explain the decreasing trend in the Baltic/Wadden Sea eider population during the last decades as an additive effect of top-down and bottom-up factors, and likely as an interaction between them.
- Keywords
- Haliaeetus albicilla, Somateria mollissima, bottom-up effects, breeding success, fertilizer, marine environments, mussel stocks, nutrients,
- MeSH
- Eagles * MeSH
- Ducks MeSH
- Population Dynamics MeSH
- Predatory Behavior MeSH
- Nutrients MeSH
- Animals MeSH
- Check Tag
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
