Telomere-to-telomere genome assembly of the goose Anser cygnoides.

Our study presents the assembly of a high-quality Taihu goose genome at the Telomere-to-Telomere (T2T) level. By employing advanced sequencing technologies, including Pacific Biosciences HiFi reads, Oxford Nanopore long reads, Illumina short reads, and chromatin conformation capture (Hi-C), we achieved an exceptional assembly. The T2T assembly encompasses a total length of 1,197,991,206 bp, with contigs N50 reaching 33,928,929 bp and scaffold N50 attaining 81,007,908 bp. It consists of 73 scaffolds, including 38 autosomes and one pair of Z/W sex chromosomes. Importantly, 33 autosomes were assembled without any gap, resulting in a contiguous representation. Furthermore, gene annotation efforts identified 34,898 genes, including 436,162 RNA transcripts, encompassing 806,158 exons, 743,910 introns, 651,148 coding sequences (CDS), and 135,622 untranslated regions (UTR). The T2T-level chromosome-scale goose genome assembly provides a vital foundation for future genetic improvement and understanding the genetic mechanisms underlying important traits in geese.

Identifying candidate genes and biological pathways in muscle development through multi-tissue transcriptome comparisons between male and female geese.

Males and females have long shown disparities in body weight and height; yet, the underlying mechanisms influencing growth and development remain unclear. Male and female Zhedong White Geese (ZDW) geese have long been selected for large body size and egg production, respectively. This led to a large difference in body weight between males and females, making them a unique model for studying the effects of sex on growth and development. This study aimed to elucidate these mechanisms by comparing the transcriptomes of muscle and pituitary tissues in male and female ZDW geese to identify the critical genes responsible for the effects of sex on growth performance. Our analysis revealed 1101 differentially expressed genes (DEGs) in leg musculature (507 upregulated, 594 downregulated), 773 DEGs in breast musculature (311 upregulated, 462 downregulated), and 517 DEGs in the pituitary gland (281 upregulated, 236 downregulated) between male and female geese. These DEGs were significantly enriched in gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with endocrine metabolism (e.g., hormonal activities), muscle formation (e.g., sarcomere and myofibril), and bone formation (e.g., bone morphogenesis and cartilage formation). The upregulated genes in males were enriched in KEGG pathways involving nutrient digestion and absorption (vitamin and protein), as well as the secretion of digestive juices (gastric acid and bile). Through protein-protein interaction analyses, we also observed high-density gene networks related to muscle fiber development, calcium ion metabolism, mitochondrial respiratory chain, and bone development. Therefore, our multi-tissue transcriptome analysis provides a deeper understanding of the complex and systematic gender-driven effects on growth and development in geese. IGF1, GHRHR, and NCAPG-LCORL and pathways related to myogenesis might play vital roles in gender differences before hormones exert their effect.

Visual lateralization in the sky: Geese manifest visual lateralization when flying with pair mates.

The brain's sensory lateralization involves the processing of information from the sensory organs primarily in one hemisphere. This can improve brain efficiency by reducing interference and duplication of neural circuits. For species that rely on successful interaction among family partners, such as geese, lateralization can be advantageous. However, at the group level, one-sided biases in sensory lateralization can make individuals predictable to competitors and predators. We investigated lateral preferences in the positioning of pair mates of Greater white-fronted geese Anser albifrons albifrons. Using GPS-GSM trackers, we monitored individual geese in flight throughout the year. Our findings indicate that geese exhibit individual lateral biases when viewing their mate in flight, but the direction of these biases varies among individuals. We suggest that these patterns of visual lateralization could be an adaptive trait for the species with long-term social monogamy, high levels of interspecies communication and competition, and high levels of predator and hunting pressure.

White Roman Goose Feather-Inspired Unidirectionally Inclined Conical Structure Arrays for Switchable Anisotropic Self-Cleaning.

White Roman goose (Anser anser domesticus) feathers, comprised of oriented conical barbules, are coated with gland-secreted preening oils to maintain a long-term nonwetting performance for surface swimming. The geese are accustomed to combing their plumages with flat bills in case they are contaminated with oleophilic substances, during which the amphiphilic saliva spread over the barbules greatly impairs their surface hydrophobicities and allows the trapped contaminants to be anisotropically self-cleaned by water flows. Particularly, the superhydrophobic behaviors of the goose feathers are recovered as well. Bioinspired by the switchable anisotropic self-cleaning functionality of white Roman geese, superhydrophobic unidirectionally inclined conical structures are engineered through the integration of a scalable colloidal self-assembly technology and a colloidal lithographic approach. The dependence of directional sliding properties on the shape, inclination angle, and size of conical structures is systematically investigated in this research. Moreover, their switchable anisotropic self-cleaning functionalities are demonstrated by Sudan blue II/water (0.01%) separation performances. The white Roman goose feather-inspired coatings undoubtedly offer a new concept for developing innovative applications that require directional transportation and the collection of liquids.

Host-derived lactic acid bacteria alleviate short beak and dwarf syndrome by preventing bone loss, intestinal barrier disruption, and inflammation.

Short-beak and dwarf syndrome (SBDS) is caused by novel goose parvovirus (NGPV) infection, which leads to farm economic losses. Our research aimed to investigate the potential of administering isolated lactic acid bacteria (LAB) in alleviating SBDS in ducks. Eight wild LAB strains were isolated from duck feces and their biosecurity was investigated in both duck embryo fibroblast (DEF) and live ducks. Moreover, the LAB strains exhibited no detrimental effects on bone metabolism levels and facilitated the tight junction proteins (TJPs) mRNA expression, and contributing to the mitigation of inflammation in healthy ducks. Subsequently, we conducted in vitrol and in vivo experiments to assess the impact of LAB on NGPV infection. The LAB strains significantly reduced the viral load of NGPV and downregulated the mRNA levels of pro-inflammatory factors in DEF. Additionally, LAB treatment alleviated SBDS in NGPV-infected ducks. Furthermore, LAB treatment alleviated intestinal damage, and reduced the inflammatory response, while also mitigating bone resorption in NGPV-infected ducks. In conclusion, the LAB strains isolated from duck feces have favorable biosecurity and alleviate SBDS in ducks, and the mechanism related to LAB improves intestinal barrier integrity, alleviates inflammation, and reduces bone resorption. Our study presents a novel concept for the prevention and treatment of NGPV, thereby establishing a theoretical foundation for the future development of probiotics in the prevention and treatment of NGPV.

Geese as reservoirs of human colon cancer-associated Streptococcus gallolyticus.

Recently, an increased number of reports have described pathogens of animal origin that cause a variety of infections and a rise in their transmission to humans. Streptococcus gallolyticus, a member of the Streptococcus bovis/Streptococcus equinus complex (SBSEC), is one of these pathogens and infects a wide range of hosts from mammals to poultry and has a broad functionality ranging from pathogenicity to food fermentation. As S. gallolyticus causes complications including bacteremia, infective endocarditis, and colorectal malignancy in humans, it is important to investigate its occurrence in various hosts, including geese, to prevent potential zoonotic transmissions. This study aimed to investigate the presence of S. gallolyticus in the droppings of clinically healthy and diarrheic geese, which were raised intensively and semi-intensively, by the in vitro culture method, characterize the isolates recovered by PCR and sequence-based molecular methods and determine their antibiotic susceptibility by the disk diffusion and gradient test methods. For this purpose, 150 samples of fresh goose droppings were used. Culture positivity for S. gallolyticus was determined as 8% (12/150). PCR analysis identified 54.55% (n = 6) of the isolates as S. gallolyticus subsp. gallolyticus and 45.45% (n = 5) as S. gallolyticus subsp. pasteurianus. Following the 16S rRNA sequence and ERIC-PCR analyses, S. gallolyticus subspecies exhibited identical cluster and band profiles that could be easily distinguished from each other and were clonally identified. High rates of susceptibility to florfenicol, penicillin, rifampicin, and vancomycin were detected among the isolates, regardless of the subspecies diversity. Both subspecies showed high levels of resistance to bacitracin, clindamycin, doxycycline, tetracycline, trimethoprim-sulfamethoxazole, and erythromycin and multiple MDR profiles, indicating their potential to become superbugs. This first report from Türkiye demonstrates the occurrence of the S. gallolyticus subspecies in geese. In view of the recent increase of geese production and the consumption of goose meat in Türkiye, the occurrence of S. gallolyticus in geese should not be ignored to prevent zoonotic transmission.

Follicular fluid-derived exosomal HMOX1 promotes granulosa cell ferroptosis involved in follicular atresia in geese (Anser cygnoides).

The proliferation and death of granulosa cells (GCs) in poultry play a decisive role in follicular fate and egg production. The follicular fluid (FF) contains a variety of nutrients and genetic substances to ensure the communication between follicular cells. Exosomes, as a new intercellular communication, could carry and transport the proteins, RNA, and lipids to react on GCs, which had been found in FF of various domestic animals. Whether exosomes of FF in poultry play a similar role is unclear. In this study, geese, a poultry with low egg production, were chosen, and the effect of FF exosomes on the proliferation and death of GCs was investigated. Firstly, there were not only a large number of healthy small yellow follicles (HSYFs) but also some atresia small yellow follicles (ASYFs) in the egg-laying stage. Also, the GC layers of ASYFs became loose interconnections, inward detachment, and diminished survival rate than that of HSYFs. Besides, compared to HSYFs, the contents of E2, P4, and the mRNA expression levels of ferroptosis-related genes GPX4, FPN1, and FTH1 were significantly decreased, while COX2, NCOA4, VDAC3 mRNA were significantly increased, and the structure of mitochondrial cristae disappeared and the outer membrane broke in the GC layers of ASYFs. Moreover, the ROS, MDA, and oxidation levels in the GC layers of ASYFs were significantly higher than those of HSYFs. All these hinted that ferroptosis might result in a large number of GCs death and involvement in follicle atresia. Secondly, FF exosomes were isolated from HSYFs and ASYFs, respectively, and identified by TEM, NTA, and detection of exosome marker proteins. Also, we found the exosomes were phagocytic by GCs by tracking CM-Dil. Moreover, the addition of ASYF-FF exosomes significantly elevated the MDA content, Fe2+ levels, and the mitochondrial membrane potential (MMP) in GCs, thus significantly inhibiting the proliferation of GCs, which was restored by the ferroptosis inhibitor ferrostatin-1. Thirdly, the proteomic sequencing was performed between FF-derived exosomes of HSYFs and ASYFs. We obtained 1615 differentially expressed proteins, which were mainly enriched in the protein transport and ferroptosis pathways. Among them, HMOX1 was enriched in the ferroptosis pathway based on differential protein-protein interaction network analysis. Finally, the role of HMOX1 in regulating ferroptosis in GCs was further explored. The highly expressed HMOX1 was observed in the exosomes of ASYF-FF than that in HSYF-FF. Overexpression of HMOX1 increased ATG5, LC3II, and NCOA4 expression and reduced the expression of FTH1, GPX4, PCBP2, FPN1 in the ferroptosis pathway, also promoted intracellular Fe2+ accumulation and MDA surge, which drove ferroptosis in GCs. The effects of HMOX1 on ferroptosis could be blocked by its inhibitor Znpp. Taken together, the important protein HMOX1 was identified in FF, which could be delivered to GCs via exosomes, triggering ferroptosis and thus determining the fate of follicles.

The protective effects of Lactobacillus SNK-6 on growth, organ health, and intestinal function in geese exposed to low concentration Aflatoxin B1.

Aflatoxin B1 (AFB1) is a prevalent mycotoxin present in feed ingredients. In this study, we investigated the effects of Lactobacillus salivarius (L. salivarius) on the Landes geese exposed to AFB1. The 300 one-day-old Landes geese were randomly divided into five groups: The control group received a basic diet, while the other groups were fed a basic diet supplemented with 10 µg/kg AFB1, 10 µg/kg AFB1+ 4*108 cfu/g L. salivarius, 50 µg/kg AFB1, and 50 µg/kg AFB1 + 4*108 cfu/g L. salivarius for 63 d. Results showed that high level AFB1 exposure significantly decreased final BW and ADG, increased feed/gain ratio (F/G) and liver index (P < 0.05). L. salivarius improved levels of IL-1, IL-6, and IL-12 under low level of AFB1 exposure (P < 0.05), along with similar trends observed in serum IgA, IgG, IgM, T3, T4, TNF-ɑ, and EDT (P < 0.05). AFB1 exposure reduced jejunum villus high and villus high/crypt depth ratio, and suppressed expression of ZO-1, Occludin, and Claudin-1 mRNA, and significant improved with L. salivarius supplementation under low level AFB1 exposure (P < 0.05). AFB1 significantly increased expression levels of TLR3 and NF-kB1, with supplementation of L. salivarius showing significant improvement under low AFB1 exposure (P < 0.05). Cecal microbiota sequencing revealed that under low level AFB1 exposure, supplementation with L. salivarius increased the abundance of Bacteroidetes and Lactococcus. In summary, supplementation with 4*108 cfu/g L. salivarius under 10 µg/kg AFB1 exposure improved growth performance and immune capacity, enhanced jejunum morphology, reduced liver inflammation, altered the cecal microbial structure, and positively affected the growth and development of geese.

Goose IFIT5 positively regulates goose astrovirus replication in GEF cells.

Interferon-induced protein with tetratricopeptide repeats (IFITs), a family of proteins strongly induced by type I interferon (IFN-I), are deeply involved in many cellular and viral processes. IFIT5, the sole protein in this family found in birds, also plays a crucial role in regulating virus infection. In this study, goose IFIT5 (gIFIT5) was first cloned from peripheral blood lymphocyte (PBL) and phylogenetic analysis showed that it was highly homologous with duck IFIT5 (dIFIT5), sharing 94.6% identity in amino acid sequence. Subsequently, the expression kinetics of gIFIT5 during goose astrovirus (GAstV) infection and the regulatory effect of gIFIT5 on GAstV proliferation were evaluated. Results showed that the mRNA and protein expression level of gIFIT5 was greatly induced by GAstV infection, especially at 12 hpi. Importantly, gIFIT5 could conversely promote GAstV replication in GEF cells. Virus titers in gIFIT5 overexpression group were significantly higher than those in control group at 12 and 24 hpi. Western blot and quantitative real-time PCR (qRT-PCR) further demonstrated that the production of viral cap protein was significantly facilitated in gIFIT5-transfected group. Collectively, GAstV facilitates self-replication via promoting gIFIT5 expression.

First report of goose circovirus identified in ducks from China.

Goose circovirus (GoCV) is a common pathogen that causes immunosuppression and promotes secondary infections with other infectious agents in geese worldwide. In the present study, we identified GoCV in 2 out of 93 duck flocks from China and successfully sequenced the complete genomes of 2 strains (AH22du and HN20du). The whole genome of the two strains shared a high identity of 90.5 to 98.63% with China GoCV reference, and low identity of 58.98% with DuCV reference, respectively. Phylogenetic tree constructed on the two and other genome sequences of GoCV revealed three main branches. Both strains sequenced in this study were distributed on different sub-branches with most other Chinese GoCV strains, and AH22du clustered into an independent sub-branch within the cluster. Recombination analysis predicted that HN20du might potentially recombine from the major parent of yk4 (Zhejiang Province, China, 2007) and minor parent of GD/YJ/g2 (Guangdong Province, China, 2020). To the best of our knowledge, this is the first report of GoCV in ducks from China. This broadened host spectrum of GoCVs requires attention from the waterfowl industry and researchers.

Alteration of gut microbiome in goslings infected with goose astrovirus.

Goose astrovirus (GoAstV) is an emerging avian pathogen that induces gout in goslings with a mortality of up to 50%. Organ damage caused by GoAstV infection was considered the cause of gout, but it is still unclear whether other factors are involved. Human and murine studies have linked the gut microbiome-derived urate and gout, thus we hypothesized that gut microbiome may also play an important role in gout induced by GoAstV infection. This study tested the pathogenicity of our isolated GoAstV genotype 2 strain on goslings, while the appearance of clinical signs, histopathological changes, viral distribution and the blood level of cytokines were monitored for 18 d postinfection (dpi). The dynamics in the gut microbiome were profiled by 16S sequencing and then correlated with GoAstV infection. Results showed that this study successfully developed an experimental infection model for studying the pathogenicity of the GoAstV infection which induces typical symptoms of gout. GoAstV infection significantly altered the gut microbiome of goslings with the enrichment of potential proinflammatory bacteria and depletion of beneficial bacteria that can produce short-chain fatty acids. More importantly, the microbial pathway involved in urate production was significantly increased in goslings infected with GoAstV, suggesting that gut microbiome-derived urate may also contribute to the gout symptoms. Overall, this study demonstrated the role of gut microbiome in the pathogenesis of GoAstV infection, highlighting the potential of gut microbiome-based therapeutics against gout symptoms.

The DNA methylation status of the vitamin A signaling associated with testicular degeneration induced by long-day photoperiods in Magang geese.

Magang geese are typical short-day breeders whose reproductive behaviors are significantly influenced by photoperiod. Exposure to a long-day photoperiod results in testicular regression and spermatogenesis arrest in Magang geese. To investigate the epigenetic influence of DNA methylation on the seasonal testicular regression in Magang geese, we conducted whole-genome bisulfite sequencing and transcriptome sequencing of testes across 3 reproductive phases during a long-day photoperiod. A total of 250,326 differentially methylated regions (DMR) were identified among the 3 comparison groups, with a significant number showing hypermethylation, especially in intronic regions of the genome. Integrating bisulfite sequencing with transcriptome sequencing data revealed that DMR-associated genes tend to be differentially expressed in the testes, highlighting a potential regulatory role for DNA methylation in gene expression. Furthermore, there was a significant negative correlation between changes in the methylation of CG DMRs and changes in the expression of their associated genes in the testes. A total of 3,359 DMR-associated differentially expressed genes (DEG) were identified; functional enrichment analyses revealed that motor proteins, MAPK signaling pathway, ECM-receptor interaction, phagosome, TGF-beta signaling pathway, and calcium signaling might contribute to the testicular regression process. GSEA revealed that the significantly enriched activated hallmark gene set was associated with apoptosis and estrogen response during testicular regression, while the repressed hallmark gene set was involved in spermatogenesis. Our study also revealed that methylation changes significantly impacted the expression level of vitamin A metabolism-related genes during testicular degeneration, with hypermethylation of STRA6 and increased calmodulin levels indicating vitamin A efflux during the testicular regression. These findings were corroborated by pyrosequencing and real-time qPCR, which revealed that the vitamin A metabolic pathway plays a pivotal role in testicular degeneration under long-day conditions. Additionally, metabolomics analysis revealed an insufficiency of vitamin A and an abnormally high level of oxysterols accumulated in the testes during testicular regression. In conclusion, our study demonstrated that testicular degeneration in Magang geese induced by a long-day photoperiod is linked to vitamin A homeostasis disruption, which manifests as the hypermethylation status of STRA6, vitamin A efflux, and a high level of oxysterol accumulation. These findings offer new insights into the effects of DNA methylation on the seasonal testicular regression that occurs during long-day photoperiods in Magang geese.

Potential regulator of meat quality in geese: C1QTNF1 implications on cell proliferation and muscle growth.

Goose creates important economic value depending on their enrich nutrients of meat. Our previous study investigates potential candidate genes associated with variations in meat quality between Xianghai Flying (XHF) Goose and Zi Goose through genomic and transcriptome integrated analysis. Screening of 5 differential expression candidate genes related to muscle development identified by the FST, XP-EHH and RNA-seq in breast muscle from various geese. Among them, C1QTNF1 (C1q and TNF related protein 1), a gene of unknown function in goose, which observed mutations in coding sequence regions in sequencing data. Its function was explored after overexpression and knockdown which designed depending on the genetic sequence of the goose, respectively. Results showed that over-expression of C1QTNF1 significantly enhances cell proliferation and viability. In addition, the expression levels of the fusion marker gene Myomaker and the differentiation marker gene MyoD are significantly upregulated in cells. Knock-down C1QTNF1 leads to down regulated Myomaker and MyoD which involved muscle formation. But, the expression level of muscle atrophy marker MuRF is not significantly changed among different transfection groups. Since protein structures and interactions are closely related to their functions, we further analyzed the C1QTNF1 for physicochemical properties, structural predictions, protein interactions and homology. It can be reasonably inferred that C1QTNF1 has a similar effect to collagen, which may affect muscle development. In summary, we first speculate that C1QTNF1 may play an important regulatory role in muscle growth and development and thereby contributes to the further understanding of the genetic mechanisms that underlie meat quality traits of goose.

Comprehensive analysis of the differential expression of mRNAs, lncRNAs, and miRNAs in Zi goose testis with high and low sperm mobility.

Sperm mobility (SM) is an objective index for measuring sperm motility; however, the mechanisms underlying its regulation in geese remain unclear. The present study sought to elucidate the genetic mechanism underlying SM traits in Zi geese (Anser cygnoides L.). To this end, three successive experiments were performed. In Experiment I, SM was determined in 40 ganders; the 3 ganders with the highest mobility and three with the lowest mobility were assigned to the high and low sperm mobility rank (SMR) groups, respectively. In Experiment II, the differences in fertility between the two SMR groups were assessed within two breeding flocks comprising the selected six ganders from Experiment I and 30 females (each flock had 3 ganders and 15 females). In Experiment III, the testes of the 6 ganders were harvested for histological observation and whole-transcriptome sequencing. Results revealed better fertility, well-developed seminiferous tubules, and abundant mature sperm in the high-SMR-flock compared to those of the low-SMR-flock (89 vs. 81%) (P < 0.05). Differential expression (DE) analysis identified 76 mRNAs, 344 lncRNAs, and 17 miRNAs between the SMR groups, with LOC106049708, XPNPEP3, GNB3, ADCY8, PRKAG3, oha-miR-182-5p, and ocu-miR-10b-5p identified as key mRNAs and miRNAs contributing to SM. Enrichment analysis implicated these DE RNAs in pathways related to ATP binding, cell metabolism, apelin signaling, Wnt signaling, and Adherens junctions. Additionally, competing endogenous RNA (ceRNA) networks comprising 9 DE mRNAs, 17 DE miRNAs, and 169 DE lncRNAs were constructed. Two ceRNA network pathways (LOC106049708-oha-miR-182-5p-MSTRG.2479.6 and PRKAG3-ocu-miR-10b-5p-MSTRG.9047.14) were identified as key regulators of SM in geese. These findings offer crucial insights into the identification of key genes and ceRNA pathways influencing sperm mobility in geese.

Shell temperature: How shall we tell if a still gosling is under the eggshell?

The present investigation was aimed at predicting a still (i.e., dead) vs. live embryo within a hatching goose egg by measuring the eggshell cooling rate. For this, we daily measured the temperature (T) values on the shell surface of goose eggs after they were removed from the incubator and during further natural cooling. T was recorded every 0.5 h for further 1.5 h of cooling. It was possible to recognize eggs with dead embryos using the combination of T, egg weight (W), and surface area (S). The resultant indicator (TS/W) was called specific temperature index (STI). The mathematical relationship using STI measurements between Days 8-13 facilitated 80 % correct identification of the eggs with dead embryos. Additionally, we derived mathematical dependencies for shell weight (Ws) and thickness (t) by utilizing the values of W, egg volume (V), S, the average T of all measurements taken, as well as the drop in T during 1.5 h of natural cooling. The key advantage of these parameters was their measurement and/or calculation by applying non-destructive methods. The integrated application of these parameters resulted in achieving high calculation accuracy as judged by correlation coefficients of 0.908 for Ws and 0.593 for t. These novel mathematical models have the potential to decrease hatching waste by predicting embryo viability. Our research will add to a toolkit for non-invasive egg assessment that is useful in the poultry industry, research on eggs, and engineering.

Lactobacillus salivarius Ameliorates AFB1-induced hepatotoxicity via PINK1/Parkin-mediated mitophagy in Geese.

Aflatoxin B1 (AFB1) is commonly found in feed ingredients and foods all over the world, posing a significant threat to food safety and public health in animals and humans. Lactobacillus salivarius (L. salivarius) was recorded to improve the intestinal health and performance of chickens. However, whether L. salivarius can alleviate AFB1-induced hepatotoxicity in geese was unknown. A total of 300 Lande geese were randomly assigned to five groups: control group, AFB1 low-dose group (L), L. salivarius+AFB1 low-dose group (LL), AFB1 high dosage groups (H), L. salivarius+AFB1 high dosage groups (LH), respectively. The results showed that the concentrations of ALT, AST, and GGT significantly increased after exposure to AFB1. Similarly, severe damage of hepatic morphology was observed including the hepatic structure injury and inflammatory cell infiltration. The oxidative stress was evidenced by the elevated concentrations of MDA, and decreased activities of GSH-Px, GSH and SOD. The observation of immunofluorescence, real-time PCR, and western blotting showed that the expression of PINK1 and the value of LC3II/LC3I were increased, but that of p62 significantly decreased after AFB1 exposure. Moreover, the supplementation of L. salivarius effectively improved the geese performance, ameliorated AFB1-induced oxidative stress, inhibited mitochondrial mitophagy and enhanced the liver restoration to normal level. The present study demonstrated that L. salivarius ameliorated AFB1-induced the hepatotoxicity by decreasing the oxidative stress, and regulating the expression of PINK1/Parkin-mediated mitophagy in the mitochondria of the geese liver. Furthermore, this investigation suggested that L. salivarius might serve as a novel and safe additive for preventing AFB1 contamination in poultry feed.

Effects of feed conditioning temperature on pellet quality, growth performance, intestinal development and blood parameters of geese from 1 to 28 d of age.

A 28-d experiment was conducted to investigate the effects of feed-conditioning temperature on the pellet quality, growth performance, intestinal development, and blood parameters of geese. A total of 180 one-day-old White Yuzhou goslings were randomly allotted to 5 treatment groups, with 6 replicates containing 6 birds each. Five diets were conditioned at 65, 70, 75, 80, and 85°C. Body weight and feed intake per pen basis were recorded from the arrival to the end of the trial. Blood and small intestine samples were collected on d 28 for analysis. The results showed that the pellet durability index (PDI), pellet hardness, and gelatinisation degree of starch (GDS) increased with increasing conditioning temperature (P < 0.05). The final body weight (FBW), average daily gain (ADG) and average daily feed intake (ADFI) of goslings significantly increased when conditioning temperature increased from 65 or 70°C to 80 or 85°C (P < 0.05), accompanied by unaffected feed conversion ratio (FCR) (P > 0.05). The villus height to crypt depth ratio (VH/CD) in the duodenum and ileum improved with increasing conditioning temperature (P < 0.05). Additionally, trypsin and amylase activity were enhanced when the conditioning temperature increased from 65 to 85°C (P < 0.05). No significant differences in the carcass traits and blood parameters of goslings were observed among the groups (P > 0.05). Overall, under the present experimental conditions, increasing the steam-conditioning temperature of pelleted feed improved pellet quality, growth performance, intestinal morphology, and digestive enzyme activity in goslings. Based on broken-line regression analysis, the lower critical conditioning temperature for ADG in geese from 1 to 28 d of age was 80.95°C.

Development of a label-free photoelectrochemical immunosensor for novel astrovirus detection.

Since 2017, an infectious goose gout disease characterized by urate precipitation in viscera, mainly caused by novel goose astrovirus (GoAstV) infection, has emerged in the main goose-producing region of China. The current challenge in managing goose gout disease is largely due to the absence of a rapid and efficient detection method for the GoAstV pathogen. Notably, the potential application of immunosensors in detecting GoAstV has not yet been explored. Herein, a label-free PEC immunosensor was fabricated by using purchased TiO2 as the photoactive material and antibody against GoAstV P2 proteins as the specific recognition element. First, we successfully expressed the capsid spike domain P2 protein of ORF2 from GoAstV CHSH01 by using the pET prokaryotic expression system. Meanwhile, the polyclonal antibody against GoAstV capsid P2 protein was produced by purified protein. To our knowledge, this is the first establishment and preliminary application of the label-free photoelectrochemical immunosensor method in the detection of AstV. The PEC immunosensor had a linear range of 1.83 fg mL-1 to 3.02 ng mL-1, and the limit of detection (LOD) was as low as 0.61 fg mL-1. This immunosensor exhibited high sensitivity, great specificity, and good stability in detecting GoAstV P2 proteins. To evaluate the practical application of the immunosensor in real-world sample detection, allantoic fluid from goose embryos was collected as test samples. The results indicated that of the eight positive samples, one false negative result was detected, while both negative samples were accurately detected, suggesting that the constructed PEC immunosensor had good applicability and practical application value, providing a platform for the qualitative detection of GoAstV.

Codon usage bias of goose circovirus and its adaptation to host.

Goose circovirus (GoCV), a potential immunosuppressive virus possessing a circular single-stranded DNA genome, is widely distributed in both domesticated and wild geese. This virus infection causes significant economic losses in the waterfowl industry. The codon usage patterns of viruses reflect the evolutionary history and genetic architecture, allowing them to adapt quickly to changes in the external environment, particularly to their hosts. In this study, we retrieved the coding sequences (Rep and Cap) and the genome of GoCV from GenBank, conducting comprehensive research to explore the codon usage patterns in 144 GoCV strains. The overall codon usage of the GoCV strains was relatively similar and exhibited a slight bias. The effective number of codons (ENC) indicated a low overall extent of codon usage bias (CUB) in GoCV. Combined with the base composition and relative synonymous codon usage (RSCU) analysis, the results revealed a bias toward A- and G-ending codons in the overall codon usage. Analysis of the ENC-GC3s plot and neutrality plot suggested that natural selection plays an important role in shaping the codon usage pattern of GoCV, with mutation pressure having a minor influence. Furthermore, the correlations between ENC and relative indices, as well as correspondence analysis (COA), showed that hydrophobicity and geographical distribution also contribute to codon usage variation in GoCV, suggesting the possible involvement of natural selection. In conclusion, GoCV exhibits comparatively slight CUB, with natural selection being the major factor shaping the codon usage pattern of GoCV. Our research contributes to a deeper understanding of GoCV evolution and its host adaptation, providing valuable insights for future basic studies and vaccine design related to GoCV.

Comparative transcriptomic analyses reveal key genes underlying melanin distribution during embryonic development in geese (Anser anser).

1. Melanin distribution typically exhibits a gradient dilution along the dorsal-ventral axis of the body, including in domestic geese. However, the specific genes and molecular mechanisms responsible for this melanin distribution pattern remain incompletely understood.2. The transcriptomic comparisons were conducted at three embryonic stages, specifically on embryonic d 15 (E15), 22 (E22), and 29 (E29), between the pigmented dorsal skin and the depigmented distal foot.3. Differentially expressed genes (DEGs) associated with melanin synthesis were identified, particularly TYR, TYRP1, and EDNRB2, which exhibited significantly higher expression levels in the dorsal skin at E15 and E22. However, expression levels significantly decreased in later stages (E29).4. The ASIP gene showed remarkably high-expression levels in the distal feet compared to the dorsal skin post-E22 stage (log2FC: 5.31/6.88 at E22/E29). Gene Ontology (GO) enrichment analysis detected eight terms associated with melanin synthesis and melanosome formation (p < 0.05), including melanosome membrane (GO: 0033162) and melanin biosynthetic process (GO: 0042438). Additionally, KEGG pathway analysis showed significant enrichment of the melanogenesis pathway (hsa004916) at d 22 (E22).