Integrative and Conjugative Elements and Prophage DNA as Carriers of Resistance Genes in Erysipelothrix rhusiopathiae Strains from Domestic Geese in Poland.

Goose erysipelas is a serious problem in waterfowl breeding in Poland. However, knowledge of the characteristics of Erysipelothrix rhusiopathiae strains causing this disease is limited. In this study, the antimicrobial susceptibility and serotypes of four E. rhusiopathiae strains from domestic geese were determined, and their whole-genome sequences (WGSs) were analyzed to detect resistance genes, integrative and conjugative elements (ICEs), and prophage DNA. Sequence type and the presence of resistance genes and transposons were compared with 363 publicly available E. rhusiopathiae strains, as well as 13 strains of other Erysipelothrix species. Four strains tested represented serotypes 2 and 5 and the MLST groups ST 4, 32, 242, and 243. Their assembled circular genomes ranged from 1.8 to 1.9 kb with a GC content of 36-37%; a small plasmid was detected in strain 1023. Strains 1023 and 267 were multidrug-resistant. The resistance genes detected in the genome of strain 1023 were erm47, tetM, and lsaE-lnuB-ant(6)-Ia-spw cluster, while strain 267 contained the tetM and ermB genes. Mutations in the gyrA gene were detected in both strains. The tetM gene was embedded in a Tn916-like transposon, which in strain 1023, together with the other resistance genes, was located on a large integrative and conjugative-like element of 130 kb designated as ICEEr1023. A minor integrative element of 74 kb was identified in strain 1012 (ICEEr1012). This work contributes to knowledge about the characteristics of E. rhusiopathiae bacteria and, for the first time, reveals the occurrence of erm47 and ermB resistance genes in strains of this species. Phage infection appears to be responsible for the introduction of the ermB gene into the genome of strain 267, while ICEs most likely play a key role in the spread of the other resistance genes identified in E. rhusiopathiae.

Effects of Goose Astrovirus Type 2 Infection on Peripheral Blood Lymphocyte and Macrophage Activity In Vitro.

Goose astrovirus type 2 (GAstV-2) is a novel pathogen causing visceral gout in goslings; it not only causes necrosis of renal epithelial cells but also causes spleen damage, indicating that GAstV-2 induces immunosuppression in goslings. However, to date, the interaction between GAstV-2 and immune cells remains unclear. In this study, peripheral blood lymphocytes and macrophages were isolated from goslings without GAstV-2 infection and then inoculated in vitro with GAstV-2, and the virus localization in the lymphocytes and macrophages, proliferation and apoptosis of lymphocytes, and phagocytic activity, reactive oxygen species (ROS) and nitric oxide (NO) production, and cell polarity in macrophages were determined. The results showed that GAstV-2 was observed in the cytoplasm of CD4 and CD8 T cells and macrophages, indicating that GAstV-2 can infect both lymphocytes and macrophages. GAstV-2 infection reduced the lymphocyte proliferation induced by Concanavalin A and lipopolysaccharide stimulation and increased the lymphocyte apoptosis rate and mRNA expression of Fas, demonstrating that GAstV-2 causes damage to lymphocytes. Moreover, GAstV-2 infection enhanced phagocytic activity and production of ROS and NO and induced a proinflammatory phenotype in macrophages (M1 macrophages), indicating that macrophages play an antiviral role during GAstV-2 infection. In conclusion, these results demonstrate that GAstV-2 infection causes damages to lymphocytes, and host macrophages inhibit GAstV-2 invasion during infection.

Protein profile analysis of Jilin white goose testicles at different stages of the laying cycle by DIA strategy.

BACKGROUND: Jilin white goose is an excellent local breed in China, with a high annual egg production and laying eggs mainly from February to July each year. The testis, as the only organ that can produce sperm, can affect the sexual maturity and fecundity of male animals. Its growth and development are affected and regulated by a variety of factors. Proteomics is generally applied to identify and quantify proteins in cells and tissues in order to understand the physiological or pathological changes that occur in tissues or cells under specific conditions. Currently, the female poultry reproductive system has been extensively studied, while few related studies focusing on the regulatory mechanism of the reproductive system of male poultry have been conducted. RESULTS: A total of 1753 differentially expressed proteins (DEPs) were generated in which there were 594, 391 and 768 different proteins showing differential expression in three stages, Initial of Laying Cycle (ILC), Peak of Laying Cycle (PLC) and End of Laying Cycle (ELC). Furthermore, bioinformatics was used to analyze the DEPs. Gene ontology (GO) enrichment, Clusters of Orthologous Groups (COG), Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein interaction (PPI) network analysis were adopted. All DEPs were found to be implicated in multiple biological processes and pathways associated with testicular development, such as renin secretion, Lysosomes, SNARE interactions in vesicle trafficking, the p53 signaling pathway and pathways related to metabolism. Additionally, the reliability of transcriptome results was verified by real-time quantitative PCR by selecting the transcript abundance of 6 selected DEPs at the three stages of the laying cycle. CONCLUSIONS: The funding in this study will provide critical insight into the complex molecular mechanisms and breeding practices underlying the developmental characteristics of testicles in Jilin white goose.

Transcriptome Profiling Unveils Key Genes Regulating the Growth and Development of Yangzhou Goose Knob.

Goose is one of the most economically valuable poultry species and has a distinct appearance due to its possession of a knob. A knob is a hallmark of sexual maturity in goose (Anser cygnoides) and plays crucial roles in artificial selection, health status, social signaling, and body temperature regulation. However, the genetic mechanisms influencing the growth and development of goose knobs remain completely unclear. In this study, histomorphological and transcriptomic analyses of goose knobs in D70, D120, and D300 Yangzhou geese revealed differential changes in tissue morphology during the growth and development of goose knobs and the key core genes that regulate goose knob traits. Observation of tissue sections revealed that as age increased, the thickness of the knob epidermis, cuticle, and spinous cells gradually decreased. Additionally, fat cells in the dermis and subcutaneous connective tissue transitioned from loose to dense. Transcriptome sequencing results, analyzed through differential expression, Weighted Gene Co-expression Network Analysis (WGCNA), and pattern expression analysis methods, showed D70-vs.-D120 (up-regulated: 192; down-regulated: 423), D70-vs.-D300 (up-regulated: 1394; down-regulated: 1893), and D120-vs.-D300 (up-regulated: 1017; down-regulated: 1324). A total of 6243 differentially expressed genes (DEGs) were identified, indicating varied expression levels across the three groups in the knob tissues of D70, D120, and D300 Yangzhou geese. These DEGs are significantly enriched in biological processes (BP) such as skin morphogenesis, the regulation of keratinocyte proliferation, and epidermal cell differentiation. Furthermore, they demonstrate enrichment in pathways related to goose knob development, including ECM-receptor interaction, NF-kappa B, and PPAR signaling. Through pattern expression analysis, three gene expression clusters related to goose knob traits were identified. The joint analysis of candidate genes associated with goose knob development and WGCNA led to the identification of key core genes influencing goose knob development. These core genes comprise WNT4, WNT10A, TCF7L2, GATA3, ADRA2A, CASP3, SFN, KDF1, ERRFI1, SPRY1, and EVPL. In summary, this study provides a reference for understanding the molecular mechanisms of goose knob growth and development and provides effective ideas and methods for the genetic improvement of goose knob traits.

Isolation, Identification, and Pathogenicity of a Goose Astrovirus Genotype 1 Strain in Goslings in China.

Goose astrovirus genotype 1 (GAstV-1) has emerged in goose farms in some provinces of China in recent years and is considered to be one of the pathogens of gout in goslings in China. However, few studies have been conducted on the dynamic distribution, tissue tropism, and pathogenesis of GAstV-1 in goslings. In 2022, an epidemiological investigation of goose astrovirus (GAstV) in goslings was conducted in seven provinces of China. During the investigation, a GAstV-1 designated as GAstV-JSXZ was identified in the kidney of an 8-day-old gosling and was successfully isolated from a goose embryo. The full genome sequence of GAstV-JSXZ was determined using the next-generation sequencing technique. The complete genome of GAstV-JSXZ was 7299-nt-long. Interestingly, the phylogenetic analysis revealed that Chinese GAstV-1 has formed two distinct subgroups based on the ORF 2 genomes, designated GAstV-1 1a and GAstV-1 1b. The GAstV-JSXZ shared the highest identity with GAstV-1 1a strain FLX and TZ03 in nucleotides (ORF1a: 98.3-98.4%; ORF1b: 92.3-99.1%; ORF2: 95.8-98.8%) and amino acid sequences (ORF1a: 99.4-99.5%; ORF1b: 98.2-98.8%; ORF2: 97.0-99.4%). To evaluate the pathogenicity of GAstV-1, 1-day-old goslings were inoculated with the virus by oral and subcutaneous injection routes, respectively. The results revealed that the virus causes extensive pathological organ damage, especially in the kidney, liver, and thymus. Virus-specific genomic RNA could be detected in the cloacal swabs and tissues of infected goslings throughout the experiment. The viral copy numbers examined in the kidney and intestine were the highest, followed by the liver and spleen. These results are likely to provide a new understanding of the pathogenicity of GAstV-1 in geese.

Phosphate type dependent phosphorylation on the interfacial and emulsion stabilizing behaviors of goose liver protein: Perspective of protein charging.

Elucidation on the emulsifying behaviors of goose liver protein (GLP) from interfacial perspective was scarce when protein charging was altered. This work aimed to elucidate the role of phosphorylation on the interfacial associative interaction and then emulsion stabilizing properties of GLP using three structurally relevant phosphates of sodium trimetaphosphate (STMP), sodium tripolyphosphate (STPP) and sodium pyrophosphate (TSPP). A monotonic increment of protein charging treated from STMP, STPP to TSPP caused progressively increased particle de-aggregation, surface hydrophobicity and structural flexibility of GLP. Compared with STMP and TSPP, STPP phosphorylation rendered the most strengthened interfacial equilibrium pressure (11.98 ± 0.24 mN/m) due to sufficient unfolding but moderated charging character conveyed. Desorption curve and interfacial protein microstructure indicated that STPP phosphorylation caused the highest interfacial connectivity between proteins adsorbed onto the same droplet, as was also verified by interfacial elastic modulus (10.3 ± 0.21 mN/m). STPP treated GLP also yielded lowest droplet size (8.16 ± 0.10 µm), flocculation (8.18%) and Turbiscan stability index (8.78 ± 0.36) of emulsion but most improved microrheological properties. Overall, phosphorylation functioned itself in fortifying the intradroplet protein-protein interaction but restraining the interdroplet aggregation, and STPP phosphorylation endowed the protein with most enhanced interfacial stabilization and emulsifying efficiency.

Rapid detection of goose megrivirus using TaqMan real-time PCR technology.

The aim of this study was to develop an efficient and accurate platform for the detection of the newly identified goose megrivirus (GoMV). To achieve this goal, we developed a TaqMan real-time PCR technology for the rapid detection and identification of GoMV. Our data showed that the established TaqMan real-time PCR assay had high sensitivity, with the lowest detection limit of 67.3 copies/µL. No positive signal can be observed from other goose origin viruses (including AIV, GPV, GoCV, GHPyV, and GoAstV), with strong specificity. The coefficients of variation of repeated intragroup and intergroup tests were all less than 1.5%, with excellent repeatability. Clinical sample investigation data from domestic Minbei White geese firstly provided evidence that GoMV can be transmitted both horizontally and vertically. In conclusion, since the TaqMan real-time PCR method has high sensitivity, specificity, and reproducibility, it can be a useful candidate tool for GoMV epidemiological investigation.

Investigations of the tick burden on passeriform, water-associated and predatory birds reveal new tick-host associations and habitat-related factors of tick infestation.

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.

Effects of dietary Artemisia annua supplementation on growth performance, antioxidant capacity, immune function, and gut microbiota of geese.

This experiment aimed to study the effect of 1% Artemisia annua added to the diet on growth performance, antioxidant capacity, immunity and intestinal morphology, and gut microbiota of geese. Seventy-two 35-day-old male geese (Zi goose) with similar body weight were selected and randomly divided into 2 groups. Each treatment group of 36 geese was divided into 6 subgroups, each having 6 male geese. The experiment lasted for 21 d. Control group (CON) was fed a basal diet and the experimental group (AAL) was fed a basal diet + 1% Artemisia annua. BW, ADG, and ADFI of the AAL group increased (p < 0.05) and the FCR decreased (p < 0.05) compared with the CON group. The addition of Artemisia annua to the diet increased catalase (CAT), glutathione peroxidase (GSH-px), and superoxide dismutase (SOD) enzyme activities, increased total antioxidant capacity (T-AOC), and decreased malondialdehyde (MDA) content in serum and jejunum of geese (p < 0.05). Meanwhile, serum IgA, IgG, IgM, and lysozyme (LZM), increased at different time points in the AAL group compared to the CON group (p < 0.05), and decrease in the content of interferon-γ (IFN-γ) , IL-6 (p < 0.05), but no effect on complement C3 and C4. Morphological observation of the small intestine showed that the jejunal crypt depth was decreased in the AAL group (p < 0.05) while elevating the jejunal villus height/crypt depth (p < 0.05). 16S rRNA sequencing results showed the Artemisia annua increased the diversity of cecum microbiota, increasing the relative abundance of Bacteroides, Fecalibacterium, and Paraprevotella. In conclusion, the addition of 1% Artemisia annua to the diet could improve the growth performance, antioxidant and immune ability of geese, as well as improve the development of the jejunum intestinal tract of geese, and change the structure of the cecum microbiota, which had a positive effect on the growth and development of geese. Artemisia annua can be further developed as a feed additive.

Molecular characterization of a virulent goose astrovirus genotype-2 with high mortality in vitro and in vivo.

Goose astrovirus (GAstV) is a newly identified viral pathogen threatening waterfowl, exhibiting a high prevalence across various regions in China. Notably, the Guanghan District of Deyang City, situated in Sichuan Province, has faced a outbreak of GAstV, resulting in significant mortality among goslings due to the induction of gout-like symptoms. In our research, we successfully isolated a GAstV strain known as GAstV SCG3. This strain exhibits efficient replication capabilities, proving virulent in goslings and goose embryos. Our study delved into the characteristics of GAstV SCG3 both in vitro and in vivo. Additionally, we examined tissue phagocytosis and the distribution of GAstV SCG3 in deceased goslings using H&E staining and IHC techniques. According to the classification established by the ICTV, GAstV SCG3 falls under the category of GAstV genotype-2. Notably, it demonstrates the highest homology with the published AHAU5 sequences, reaching an impressive 98%. Furthermore, our findings revealed that GAstV SCG3 exhibits efficient proliferation exclusively in goose embryos and in LMH cells, while not manifesting in seven other types of avian and mammalian cells. Significantly, the mortality of GAstV on goslings and goose embryos are 93.1 and 80%, respectively. Moreover, the viral load in the livers of infected goslings surpasses that in the kidneys when compared with the attenuated strain GAstV SCG2. The mortality of GAstV is usually between 20% and 50%, our study marks the first report of a virulent GAstV strain with such a high mortality.

Phenology.

Flowers blooming, fungi fruiting, insects biting, fish spawning, geese migrating, deer calving; our consciousness is steeped in a seasonal calendar of nature's events. Phenology is the study of these recurring, seasonal life-history events, though nowadays this term is widely applied to the events themselves. From Shakespeare's sonnet 98, "From you I have been absent in the spring", to the appearance of seasonal events and migratory species in the oral traditions of Native Americans, interest in phenology is long-standing and transcends cultures. In this primer we introduce the study of phenology, trace the development of the field, and examine the prominent role phenology has played in evidencing the widespread impacts of anthropogenic climate change on life on Earth. We will consider the potential implications of climatic change for the ability of populations to persist and the stability of species interactions.

Proteomic Analysis of Egg Yolk Proteins During Embryonic Development in Wanxi White Goose.

To investigate the alterations of yolk protein during embryonic development in Wanxi white goose, the egg yolk protein composition at days 0, 4, 7, 14, 18, and 25 of incubation (D0, D4, D7, D14, D18, and D25) was analyzed by two-dimensional gel electrophoresis combined with mass spectrometry. A total of 65 spots representing 11 proteins with significant abundance changes were detected. Apolipoprotein B-100, vitellogenin-1, vitellogenin-2-like, riboflavin-binding protein, and serotransferrin mainly participated in nutrient (lipid, riboflavin, and iron ion) transport, and vitellogenin-2-like showed a lower abundance after D14. Ovomucoid-like were involved in endopeptidase inhibitory activity and immunoglobulin binding and exhibited a higher expression after D18, suggesting a potential role in promoting the absorption of immunoglobulin and providing passive immune protection for goose embryos after D18. Furthermore, myosin-9 and actin (ACTB) were involved in the tight junction pathway, potentially contributing to barrier integrity. Serum albumin mainly participated in cytolysis and toxic substance binding. Therefore, the high expression of serum albumin, myosin-9, and ACTB throughout the incubation might protect the developing embryo. Apolipoprotein B-100, vitellogenin-1, vitellogenin-2-like, riboflavin-binding protein, and serotransferrin might play a crucial role in providing nutrition for embryonic development, and VTG-2-like was preferentially degraded/absorbed.

Inoculation fermentation with Lactobacillus fermentum L28 and Staphylococcus epidermidis S24 for improving the protein degradation of air-dried goose.

The inoculation fermentation technology was applied to the processing of dried cured goose to investigate the protein degradation. Lactobacillus fermentum (L), Staphylococcus epidermidis (S) and mixed strains (L + S) were individually inoculated into the whole goose before drying. We studied the degradation of protein in the air-dried period of goose. The results showed that compared with natural fermentation, inoculation fermentation significantly increased the content of non-protein nitrogen (14.85 mg/g NPN), proteolysis index (8.98% PI), myofibril fragmentation index (89.35 MFI) and total amount of free amino acids (1332.6 mg/g FAA) of dried cured goose. Electrophoresis revealed that the inoculation fermentation accelerated the degradation of macromolecular proteins and the accumulation of small molecular proteins. The degree of protein degradation in four groups of goose was in an order of L + S group > S group > L group > CK group. It suggested that inoculation fermentation could promote the degradation of myofibrillar proteins.

Parental betaine supplementation promotes gosling growth with epigenetic modulation of IGF gene family in the liver.

Betaine is widely used as a feed additive in the chicken industry to promote laying performance and growth performance, yet it is unknown whether betaine can be used in geese to improve the laying performance of goose breeders and the growth traits of offspring goslings. In this study, laying goose breeders at 39 wk of age were fed basal (Control, CON) or betaine-supplemented diets at low (2.5 g/kg, LBT) or high (5 g/kg, HBT) levels for 7 wk, and the breeder eggs laid in the last week were collected for incubation. Offspring goslings were examined at 35 and 63 d of age. The laying rate tended to be increased (P = 0.065), and the feed efficiency of the breeders was improved by betaine supplementation, while the average daily gain of the offspring goslings was significantly increased (P < 0.05). Concentrations of insulin-like growth factor 2 (IGF-2) in serum and liver were significantly increased in the HBT group (P < 0.05), with age-dependent alterations of serum T3 levels. Concurrently, hepatic mRNA expression of the IGF gene family was significantly increased in goslings derived from betaine-treated breeders (P < 0.05). A higher ratio of proliferating cell nuclear antigen (PCNA)-immunopositive nuclei was found in the liver sections of the HBT group, which was confirmed by significantly upregulated hepatic expression of PCNA mRNA and protein (P < 0.05). Moreover, hepatic expression of thyroxine deiodinase type 1 (Dio1) and thyroid hormone receptor ß (TRß) was also significantly upregulated in goslings of the HBT group (P < 0.05). These changes were associated with significantly higher levels of global DNA 5-mC methylation, together with increased expression of methyl transfer genes (P < 0.05), including betaine-homocysteine methyltransferase (BHMT), glycine N-methyltransferase (GNMT), and DNA (cytosine-5-)-methyltransferase 1 (DNMT1). The promoter regions of IGF-2 genes, as well as the predicted TRß binding site on the IGF-2 gene, were significantly hypomethylated (P < 0.05). These results indicate that gosling growth can be improved by dietary betaine supplementation in goose breeders via epigenetic modulation of the IGF gene family, especially IGF-2, in the liver.

The goose industry plays important roles in economics, cultures, and ecosystems, yet the low laying and growth rates of many indigenous breeds hinders the development of the goose farming. Betaine, an important methyl donor, is commonly used as a feed additive in livestock and poultry to enhance animal growth. Dietary supplementation of betaine in laying hens or gestational sows has been reported to promote the growth of their offspring. Here, we sought to investigate whether and how dietary betaine supplementation affects the growth and development of offspring goslings. In this study, goose breeders, both male and female, were fed a basal diet supplemented respectively with 0, 2.5, or 5 g/kg betaine for 7 wk. Goslings hatched from the breeder eggs of different groups were raised under the same standard condition for assessing the growth performance. Parental betaine increases the growth rate of offspring goslings with decreased DNA methylation on the IGF-2 gene promoter and increased expression of the IGF-2 gene in the liver. These results provide scientific evidence for the inter-generational effect of betaine on gosling growth.

Phenotypic and morphometric characterization of domestic geese raised in northern Benin.

Documentation on the domestic geese (Anser anser) in Benin is scarce, making it objectively difficult to exploit. Its production depends on small flocks raised by livestock farmers in different areas. The aim of the study was to describe the phenotypic and morphometric characteristics of geese encountered in northern Benin. To this end, a total of 576 adult geese (353 males and 223 females) from 102 farms in 4 agro-ecological zones of northern Benin were evaluated for 11 quantitative and 5 qualitative body traits. There are 6 plumage colors with white (42.01%), white-brown magpie (24.65%) and white-grey magpie (17.19%) as dominant colors. The proportions of white-grey (75%) and multicolored (51.85%) in Far northern zone of Benin (FNZB) were higher (P < 0.05) than those in the cotton zone of northern Benin (CZNB), Food-producing zone of southern Borgou (FZSB) and West-Atacora Zone (WAZ). The red coloring of the tarsi was more dominant in the FZSB (63.09%) and the FZSB (61.79%) (P < 0.05). Orange (57.47%) and yellow (28.82%) colored beaks were dominant but did not vary (P > 0.05) from one agro-ecological zone to another. Quantitative traits such as body length, tarsus length, wing span and thoracic circumference of geese varied (P < 0.05) between 71.34 to73.22 cm, 10.08 to 10.6 cm, 131.95 to 135.42 cm and between 42.07 to 43.86 cm respectively. Males differed significantly from females (P < 0.05) for all morphometric traits. The live weight of geese in the FNZB showed higher values than those of other agro-ecological zones (P ˂ 0.05). In addition, white phenotype geese (3.76 kg) were heavier (P ˂ 0.05) than other phenotypes. All correlations between weight and body measurements of domestic geese were positive, but the correlations between live weight and wing span (r = 0.68) were the strongest. These correlations could be used to assess the live weight of the geese population studied and for selection based on live weight. This study provides a reference for morpho-biometric traits and will be complemented by molecular characterization.

Aminoguanidine alleviates gout in goslings experimentally infected with goose astrovirus-2 by reducing kidney lesions.

Goose astrovirus (GAstV)-2, a novel pathogen identified in 2018, mainly causes visceral gout in goslings, leading to approximately 50% mortality. At present, no commercial veterinary products are available to prevent and treat the disease. Our previous studies showed that nitric oxide (NO) and inducible NO synthase (iNOS) were markedly higher in the kidney and spleen of goslings infected with GAstV-2, but their effects during GAstV-2 infection remain unclear. In the present study, goslings were intraperitoneally injected with aminoguanidine (AG)-an iNOS inhibitor-to examine the role of NO during GAstV-2 infection. AG significantly decreased the serum NO concentration and iNOS mRNA expression in the kidney. Moreover, AG reduced the mortality, serum uric acid and creatinine content, and urate deposition in visceral organs and joints. Histopathological analysis demonstrated that AG reduced renal tubular cell necrosis, inflammatory cell infiltration, glycogen deposition in glomerular mesangium, and interstitial fibrosis, suggesting alleviation of kidney lesions. Furthermore, AG decreased the expression of renal injury markers such as KIM-1 and desmin; inflammatory cytokine-related genes such as IL-1ß, IL-8, and MMP-9; and autophagy-related genes and proteins such as LC3II, ATG5, and Beclin1. However, quantitative real-time PCR and immunohistochemistry showed that treatment with AG did not affect the kidney and liver viral load. These findings suggest that AG decreases the mortality rate and kidney lesions in goslings infected with GAstV-2 through mechanisms associated with autophagy and inhibition of inflammatory cytokine production in the kidney but not with GAstV-2 replication.

Research Note: Antibiotic resistance and pathogenicity of geese-derived Riemerella anatipestifer isolated from eastern regions of Hebei Province, China.

Riemerella anatipestifer (R. anatipestifer) can cause serositis in multiple poultry species, resulting in significant losses. Although R. anatipestifer-caused infections in ducks have been well established, the literature about this disease in geese is rare. Here, we isolated and identified 56 strains of R. anatipestifer from the eastern regions of Hebei Province, China, and further determined their serotypes, antibiotic resistance, and pathogenicity. A total of 75 strains of causative bacteria were isolated from 70 sick geese with serositis. After Gram staining microscopy, PCR, and 16S rDNA sequence analysis, 56 isolates were identified as members of R. anatipestifer and 19 as Escherichia coli (E. coli). The results of serotyping showed that there were 4 serotypes prevalent in the isolate, including serotype 1 (37/56), serotype 2 (9/56), serotype 11 (8/56), and serotype 13 (2/56). The results of antibiotic susceptibility testing revealed that all 56 R. anatipestifer isolates showed varying degrees of multidrug resistance (MDR). A total of 10 antibiotic resistance genes (ARG) were determined in these isolates. Four isolates of different serotypes were selected for pathogenicity examination, and all were able to reproduce serositis-like symptoms in 15-day-old goslings, with neurological symptoms and a 100% mortality rate. Hemorrhagic congestion of the brain tissue, steatosis of the hepatocytes, and disorganization of some cardiac myofibers were observed in R. anatipestifer-infected geese. All these findings will contribute to our insights into the prevalence characteristics, antibiotic resistance profile, and pathogenicity of R. anatipestifer infection in geese in eastern Hebei Province and provide scientific guidance for the treatment and control of this disease.

The development rule of feathers and application of hair root tissue in sex identification of Yangzhou geese.

Accurate gender identification is crucial for the study of bird reproduction and evolution. The current study aimed to explore and evaluate the effectiveness of a noninvasive method for gender identification in Yangzhou geese. In this experiment, 600 goose eggs were collected. Hair root tissues were used for PCR amplification, molecular sequencing, and anal inversion for early sex recognition in goslings. According to the DNA amplification results for the feather pulp tissue of 2-wk-old geese, bands appeared at 436 bp (CHD1-Z) and 330 bp (CHD1-W) upon gel electrophoresis. This method considered the base of goose feathers to accelerate the process of gender recognition. By examining the sex of anatomized poultry for verification, the accuracy rate of PCR gel electrophoresis and molecular sequencing sex identification was 100%, whereas the average accuracy rate of anal inversion was 97.41%. In the comparison of feather growth trends at 0 to 18 wk of age, the feather root weight (FRW), feather root length (FRL), feather branch length (FBL), and feather shaft diameter (FSD) of Yangzhou goose of the same age were not significantly different between males and females (P > 0.05). At 6 wk of age, the FRW, FRL, and FSD in males and FRL in females increased rapidly; their growth increased by 84.43, 67.58, 45.10, and 69.42%, respectively. At 10 wk of age, the male FRL, male FBL, and female FBL increased by 37.31, 34.81, and 21.72, respectively. The Boltzmann model was found to be the best-fitting model for the feathers of male Yangzhou geese. Early sex identification based on feather growth trends between the sexes is not feasible. This study provides a convenient and reliable technical means for early sex identification of waterfowl and serves as an ecological strategy for protecting the reproduction of poultry populations.

miR-140-y targets TCF4 to regulate the Wnt signaling pathway and promote embryonic feather follicle development in Hungarian white goose.

Goose down feather has become one of the most important economical products in the goose breeding industry and it provides several essential physiological roles in birds. Therefore, understanding and regulating the development of skin and feather follicles during embryogenesis is critical for avian biology and the poultry industry. MicroRNAs are known to play an important role in controlling gene expression during skin and feather follicle development. In this study, bioinformatics analysis was conducted to select miR-140-y as a potential miRNA involved in skin and feather follicle development and to predict TCF4 as its target gene. This gene was expressed at significant levels during embryonic feather follicle development, as identified by qPCR and Western blot. The targeting relationship was confirmed by a dual-luciferase assay in 293T cells. Then, the miR-140-y/TCF4 function in dermal fibroblast cells was explored. The results showed that miR-140-y could suppress the proliferation of goose embryonic dermal fibroblast cells (GEDFs) by suppressing the activity of some Wingless-types (Wnt) pathway related genes and proliferation marker genes, while miR-140-y inhibition led to the opposite effect. Similarly, the inhibition of the TCF4 gene results in blocking the proliferation of GEDFs by reducing the activity of some Wnt pathway-related genes. Finally, the co-transfection of miR-140-y inhibitor and siRNA-TCF4 results in a rescue of the TCF4 function and an increase of the Wnt signaling pathway and GEDFs proliferation. In conclusion, these results demonstrated that the miR-140-y-TCF4 axis influences the activity of the Wnt signaling pathway and works as a dynamic regulator during skin and feather follicle development.