PAMK are heterogeneous glycans with immunomodulatory potential, but their structural basis and mechanisms in regulating thymic injury remain unclear. Structural characterization revealed that PAMK is mainly composed of arabinose, galactose, rhamnose, galacturonic acid, and glucose, featuring a dominant backbone consisting of →4)-α-D-GalpA-(1→, →4)-β-D-Galp-(1→, →2)-α-L-Rhap-(1→, and →3,4)-α-D-GalpA-(1→ with highly branched side chains. This complex structure provides the biochemical foundation for its bioactivity. To explore its immunoprotective effects, we established a CTX-induced thymic necroptosis model in goslings. CTX markedly disrupted cytokine profiles and activated necroptosis signaling, accompanied by downregulation of novel-miR-2 and upregulation of TRADD and MLKL. Dietary PAMK supplementation significantly restored cytokine homeostasis and inhibited necroptosis pathway activation. Mechanistically, PAMK upregulated novel-miR-2, which negatively regulated TRADD and MLKL expression, thereby attenuating necroptosis signaling. Overexpression of novel-miR-2 suppressed TRADD/MLKL-mediated necroptosis, whereas its inhibition produced the opposite effect. Furthermore, PAMK mitigated oxidative stress and necroptotic cell death induced by TRADD and MLKL overexpression. Collectively, our findings demonstrate that the defined structural features of PAMK underpin its ability to protect against CTX-induced thymic necroptosis by upregulating novel-miR-2 and suppressing the TRADD/MLKL axis. This work links PAMK's composition to its immunoprotective function and highlights its potential as a safe immunoregulatory agent in poultry.

Ellagitannins (ETs) are plant tannins from chestnut wood with antimicrobial, anti-inflammatory, and antioxidant properties. This study assessed adding ETs to drinking water on growth, slaughter traits, meat characteristics, serum immunity, antioxidant capacity, and intestinal health in squabs (postnatal pigeons from 0 to 28 days of age, as defined by NY/T 3651-2020). In total, 360 pairs of pigeons were randomly divided into four groups and received 0, 250, 350, 450 g/t ETs in drinking water for 30 days. Growth performance, slaughter yields, meat tenderness, jejunal morphology, serum biochemical indices, gene expression related to intestinal barrier and myogenesis, and cecal microbiota composition were analyzed. The 350 g/t ETs provided the best outcomes: highest nest weight gain, better feed conversion ratio, increased live weight and breast muscle yield and the lowest shear force (meat tenderness).ETs also improved intestinal health by elevating the villus-to-crypt (V/C) ratio, up-regulating tight junction gene expression, and modulating the cecal microbiota, particularly by increasing the abundance of beneficial Bacillota. Serum IgG levels demonstrated a dose-dependent increase with ETs supplementation. Correlation analysis showed Turicibacter abundance favorably correlated with growth performance and myogenic gene expression, whereas Escherichia-Shigella abundance showed correlations with increased antioxidant capacity and reduced myofiber diameter, consistent with a stress-associated response. Microbiota analysis revealed that Escherichia-Shigella was enriched in the ET450 group, and correlation analysis further linked its abundance to increased antioxidant capacity and reduced myofiber diameter, suggesting a stress-associated response at the highest dose. In conclusion, dietary ellagitannins, especially at 350 g/t via drinking water, effectively enhanced the growth, meat quality, and gut health of European meat pigeon squabs.

This study was conducted to investigate the effects of dietary gallic acid (GA) supplementation on growth performance and intestinal barrier function of broiler chickens challenged with lipopolysaccharide (LPS). A total of 750 1-day-old ''817'' male crossbred broilers were randomly assigned to 5 treatment groups, with six replicates per group: basal diet (CON), basal diet following LPS-challenge (LPS), and basal diet supplemented with 150, 300, 450 mg/kg GA following LPS-challenge (GA150, GA300, and GA450). On days 14, 17, and 20, chickens in the LPS, GA150, GA300, and GA450 groups received intraperitoneal injections of LPS, while chickens in the CON group received the same dose of saline. The results showed that, compared with broilers in CON, dietary supplementation with GA eliminated the negative effects of LPS on reducing BW on day 21, as well as the 1 to 21d ADFI and ADG compared to broilers in CON group (P < 0.05). Compared with the LPS group, dietary supplementation with 300 and 450 mg/kg GA significantly upregulated the relative expression of superoxide dismutase1 (SOD1), and 150 mg/kg GA significantly upregulated the relative expression of glutathione peroxidase 1 (GPX1) in ileal mucosa. Compared with the LPS group, dietary GA supplementation significantly increased the percentages of CD3+ and CD4+ T cells in the ileum, while decreased the percentage of BU-1+ B cells (P < 0.05). In addition, the plasma content of TNF-α was significantly increased under LPS stimulation. Supplementation with 150 and 300 mg/kg GA increased the levels of IL-10 and TGF-β, reduced the level of TNF-α in plasma, and upregulated the relative expression of occludin (OCLN) and mucin 2 (MUC2) in the ileal mucosa (P < 0.05). Compared with the CON group, LPS challenge significantly increased the crypt depth in the ileum (P < 0.05). However, supplementation with GA significantly increased the villus height and the villus height-to-crypt depth ratio (VCR) while significantly decreasing crypt depth after LPS challenge (P < 0.05). Firmicutes was the dominant phylum in cecal microbiota; LPS stimulation disrupted cecal microbial homeostasis, while GA exerted dose-dependent differential regulatory effects on this LPS-induced dysbiosis: 150 and 300 mg/kg GA alleviated the LPS-induced reduction in Bacteroides abundance, and 450 mg/kg GA modulated the abundance of Proteobacteria and multiple relevant bacterial genera. In conclusion, dietary GA supplementation up-regulated the expression of antioxidant-related genes in the ileal mucosa, modulated immune function, and alleviated LPS-induced intestinal barrier damage and gut dysbiosis, thereby improving the growth performance of broilers challenged with LPS.

Mitochondria play crucial roles in energy metabolism and steroidogenesis. Heat stress suppresses steroidogenesis in ovarian granulosa cells (GCs) and impairs poultry reproduction. Our previous study revealed that mitophagy protects duck GCs from acute heat exposure. Notably, numerous studies have demonstrated that the AMP-activated protein kinase/Unc-51-like kinase 1 (AMPK/ULK1) pathway is a key regulatory pathway for mitophagy. However, how AMPK coordinates mitophagy and steroidogenesis under heat stress remains unclear. This study aimed to elucidate the role of the AMPK/ULK1 axis in heat-induced mitophagy and steroidogenesis. Using a duck heat-treatment model and in vitro GC culture models, we combined Western blotting, targeted metabolomics, siRNA-mediated gene knockdown, and mitochondrial function assays to assess the impacts of the AMPK/ULK1 axis on mitophagy and steroidogenesis. We showed that heat treatment induced mitochondrial dysfunction, activated the AMPK/ULK1 pathway, triggered mitophagy, and suppressed steroidogenesis in duck ovarian tissue. In vitro, GCs exhibited similar mitochondrial impairment and AMPK/ULK1-dependent mitophagic activation under heat treatment. The LC-MS/MS analysis also confirmed elevated intracellular AMP levels in heat treatment GCs. Furthermore, activation of AMPK by 5′-aminoimidazole-4´-carboxamide ribonucleotide (AICAR) triggered mitophagy and enhanced steroidogenesis in GCs under heat treatment by upregulating the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 11A1 (CYP11A1), and cytochrome P450 19A1 (CYP19A1), whereas inhibition of AMPK by compound C exerted the opposite effect. Additionally, genetic knockdown of AMPK or ULK1 via siRNA reduced mitophagy and steroidogenesis under heat treatment. Taken together, the AMPK/ULK1 axis mediates heat-induced mitophagy and enhances GC steroidogenesis, positioning AMPK as a therapeutic target to improve heat-stressed poultry reproduction.

Local goose breeds Shitou and Wuzong exhibit distinct growth rates, implying divergent embryonic muscle development. This study used embryonic myoblasts from the Magang goose, an established model with superior growth traits, to explore the underlying common regulatory mechanisms. Extending our previous findings that 5-AZA (DNA methylation inhibitor) and BC339 (DNA hydroxylation inhibitor) oppositely affect myoblast proliferation and differentiation, we performed whole-transcriptome sequencing on inhibitor-treated goose embryonic myoblasts. This aimed to identify DNA methylation-mediated ncRNA-mRNA networks governing myoblast fate, with key interactions being functionally validated. 5-AZA significantly promotes cell proliferation and differentiation by inhibiting DNA methyltransferase activity and reducing DNA methylation levels, whereas BC339 significantly suppresses cell proliferation and differentiation by inhibiting demethylation and increasing DNA methylation levels. Specifically, we identified 6,309 mRNAs, 579 lncRNAs, 194 miRNAs, and 825 circRNAs that were differentially expressed in response to 5-AZA and BC339 treatment. Based on GO and KEGG enrichment analyses, differentially expressed genes related to muscle development were selected to construct a ceRNA network. This network comprises 5 differentially expressed lncRNAs (DELs: MSTRG.17572.1, XR_001211738.1, MSTRG.1886.1, XR_001212555.1, MSTRG.8995.2), 2 differentially expressed circRNAs (DECs: novel_circ_029953, novel_circ_017636), 11 differentially expressed miRNAs (DEMs: miR-383-x, miR-10174-y, miR-191-x, miR-24-x, miR-9619-y, novel-m0303-5p, novel-m0105-3p, miR-204-x, miR-211-z, novel-m0075, miR-26-y), 5 differentially expressed genes (DEGs: KIF3A, CCND1, PPM1A, Table 2, TGFBR1), forming a total of 24 interactions. This study identified miR-9619-y as a critical negative regulator of goose embryonic myoblast development through targeted inhibition of CCND1. Dual-luciferase reporter assays confirmed the direct binding of miR-9619-y to the 3’-untranslated region of CCND1. Functional experiments demonstrated that overexpression of miR-9619-y significantly reduced the EdU-positive cell ratio and myotube area percentage, accompanied by cell cycle arrest at the G0/G1 phase. Conversely, inhibition of miR-9619-y promoted myoblast proliferation and differentiation while decreasing the proportion of cells in G0/G1 phase. During the proliferation stage, miR-9619-y overexpression significantly suppressed CCND1 expression at both mRNA and protein levels, down-regulated MyoD expression, and reduced Myf5 mRNA abundance; whereas miR-9619-y inhibition up-regulated these genes and their corresponding proteins. During the differentiation stage, overexpression of miR-9619-y similarly decreased the mRNA levels of CCND1, Myh1, and MyoG, as well as the protein levels of MyHC and CCND1, with inhibition producing the opposite effects. In this study, we predicted a ceRNA network based on bioinformatics analysis governing goose embryonic myoblast development, identifying key molecular components including mRNAs, miRNAs, lncRNAs, and circRNAs, along with 24 regulatory axes. Functional experiments further demonstrated that miR-9619-y arrests cell cycle progression and negatively regulates the proliferation and differentiation of goose embryonic myoblasts, as evidenced by its impact on both the mRNA and protein expression of key myogenic factors through targeted inhibition of CCND1. These findings, together with the bioinformatically predicted ceRNA network, suggest potential complex post-transcriptional regulatory mechanisms underlying myogenesis in geese and offer candidate molecular targets for genetic improvement of meat production performance in waterfowl breeding programs.

IntroductionThis study evaluated the effects of dietary supplementation with Jiang-flavor Baijiu distiller's grains yeast culture (JBGC) on immune performance and intestinal health in geese.MethodsA total of 512 one-day-old Magang geese were randomly assigned to four dietary treatments 0% (control), 2%, 6%, or 10% JBGC with eight replicates per treatment and 16 birds per replicate, over a 70-day experimental period.ResultsJBGC supplementation exhibited dose- and time-dependent effects on antioxidant and inflammatory responses. Compared with the control, 10% JBGC significantly reduced serum glutathione peroxidase activity at day 70 and total antioxidant capacity at day 28 (P < 0.05), whereas both 6% and 10% JBGC increased hepatic total superoxide dismutase activity (P < 0.05). Regarding inflammatory markers, 10% JBGC lowered serum IL-1β at day 70 (P < 0.05), and all JBGC-supplemented groups (2%, 6%, and 10%) showed significantly lower IL-8 levels than the control during the later phase (P < 0.05). Additionally, 6 and 10% JBGC elevated the anti-inflammatory cytokine IL-10 at day 70 (P < 0.05). JBGC also improved intestinal morphology and barrier function: 6 and 10% JBGC increased ileal villus height (P < 0.05); 10% JBGC enhanced duodenal length and weight, jejunal weight, and total small intestinal weight; and 6% JBGC upregulated the protein expression of occludin and claudin?5 (P < 0.05). Although cecal microbial alpha diversity did not differ significantly, several beneficial bacterial genera showed increasing trends.DiscussionThese findings indicate that JBGC can positively modulate immune and intestinal health in geese by influencing antioxidant status, inflammatory cytokine profiles, intestinal morphology, and barrier integrity.

Shitou goose (large goose breed) and Wuzong goose (small goose breed) are important local goose breeds in Guangdong Province, exhibiting significant differences in growth performance and slaughter traits. The number of myofibers in goose skeletal muscle is determined during embryonic stage, and is subject to multiple myogenic factors and epigenetic regulation during myogenesis, among which DNA methylation is the most common and obvious epigenetic modification. In this study, we examined the expression profiles of DNA methyltransferases (DNMT1, DNMT3A, DNMT3B), DNA hydroxylases (TET1, TET2, TET3) and key myogenic factors (MYOD, MYF5, MYOG, MYHC) in embryonic and adult myoblasts, and performed DNMT1 and TET2 over-expression and interference experiments on goose embryonic myoblasts in combination with co-treatments of BC339 (TETs inhibitor) and 5AZA (DNMTs inhibitor). RT-qPCR analysis revealed Wuzong geese embryonic myoblasts exhibited significantly higher mRNA levels of TET1, TET2, and TET3 hydroxylases during early stages (E10-E22), along with elevated MYOD expression, while Shitou geese embryonic myoblasts showed increased DNMT1 and DNMT3B methyltransferases and up-regulated late-stage myogenic factors MYOG and MYHC. In myoblasts, TET2 expression peaked during proliferation, whereas DNMT1 dominated differentiation, highlighting their stage-specific regulatory roles. DNMT1 over-expression suppressed proliferation and differentiation, lower MYOD and MYHC levels, while DNMT1 interference enhanced both processes. 5AZA reversed DNMT1-mediated suppression, whereas BC339 exacerbated it. Conversely, TET2 over-expression promoted proliferation and differentiation, increased MYOD and MYHC levels, with 5AZA amplifying and BC339 attenuating these effects. TET2 interference impaired proliferation and differentiation, partially rescued by 5AZA. In this study, we investigated the relationship between DNA methylation and the proliferation and differentiation ability of goose embryonic myoblasts, which provided a theoretical basis for a systematic understanding of the molecular mechanisms underlying the differences in growth performance of goose breeds of different body sizes.

The expansion of large-scale goose farming under semi-arid conditions has exacerbated bathing pool pollution, adversely affecting goose growth performance and intestinal health. Given the crucial role of gut microbiota in maintaining intestinal homeostasis, and considering the reported beneficial effects of bacteriophages and Bacillus subtilis on gut health, this study investigated their combined application in goose production. To investigate the effects of Bacillus subtilis and phage supplementation on goose intestinal health, a 90-day trial was conducted with 288 Magang goslings randomly allocated to four treatment groups: control (A), B. subtilis (1 × 105 CFU/kg; B), bacteriophage (5 × 107 PFU/kg; C), and combined supplementation (D). The supplementation significantly enhanced body weight (p < 0.05) and feed efficiency without affecting feed intake. Notably, the combined treatment demonstrated synergistic effects in reducing serum and aquatic endotoxin levels while suppressing pathogenic bacteria (Escherichia coli and Salmonella) in water systems. Intestinal morphology improvements included increased villus height and optimized villusto-crypt ratios, accompanied by up-regulated expression of tight junction genes (Zo-1 and Ocln). Cecal microbiota analysis revealed enhanced alpha diversity and a shift toward Bacteroides-dominant communities, with concurrent suppression of Proteobacteria. Immune modulation exhibited a biphasic response, characterized by early anti-inflammatory (Tnf-α) and late-phase antioxidant (Ho-1) activities. Microbialenvironmental correlation analysis identified Firmicutes and Desulfobacterota as growth-promoting but barrier-compromising taxa, while Bacteroidota was associated with improved gut integrity. This research has shown that adding B. subtilis and bacteriophages to feed significantly enhances the intestinal barrier function of geese. The findings demonstrate that combined supplementation of B. subtilis and bacteriophages during the brooding and rearing stages optimizes growth performance through gut-microbiota-immune interactions, providing an effective antibiotic-free strategy for sustainable poultry production.

The protective effects of the polysaccharide of Atractylodes macrocephala Koidz (PAMK) against lipopolysaccharide (LPS)-induced intestinal injury in goslings was determined using 16S rRNA analysis of cecal contents and serum metabolomics analysis. PAMK was administered to goslings following LPS-induced intestinal injury, and its effects were assessed. PAMK significantly reduced the serum levels of inflammatory factors including interleukin (IL)-6 and C-reactive protein and decreased the expression of pro-inflammatory cytokines including interleukin(IL)-1 β , IL-6, and toll-like receptor 2 in jejunal tissues. Moreover, PAMK significantly upregulated the relative mRNA expression levels of the tight junction proteins Zonula occludens -1, Occludin , Claudin , and Mucin -2, enhancing the integrity of the intestinal barrier and alleviating LPS-induced intestinal injury. 16S rRNA sequencing revealed that PAMK could alleviate LPS-induced disruption of the intestinal microbiota structure and improve microbial diversity. Metabolomics analysis revealed that PAMK could influence key metabolic pathways, including the mTOR, PI3K-Akt, and FoxO signaling pathways, and regulate metabolites such as L-aspartic acid and S-adenosylmethionine. Integrated analysis indicated that PAMK could promote the enrichment of beneficial bacteria (e.g., Allobaculum and Peptococcus ) while alleviating LPS-induced microbial dysbiosis by modulating the correlation between key metabolites and specific microbial populations. Overall, PAMK could alleviate LPS induced intestinal injury by enhancing intestinal barrier function, optimizing gut microbiota composition, and regulating metabolic signaling pathways. Our findings provide a novel strategy for maintaining the intestinal health of poultry and preventing intestinal diseases.

Strong broodiness is an important reproductive characteristic of Magang geese, manifested by periodic laying-incubation activities during the breeding season. To investigate the changes in ovarian activity, follicular development, and gonadal reproductive regulators during the laying-incubation cycle, this study examined ovarian morphology, follicular development, blood reproductive hormones, and the expressions of reproductive regulators in the gonadal stroma, follicular granulosa, and membranous layer of the follicles during the laying, early broodiness, depth of broodiness, and end of broodiness periods of Magang geese. The results showed that ovarian activity degenerated and atrophied with the onset of brooding: the number of LWFs and SYFs decreased rapidly; LFY disappeared; PRL in the blood increased significantly; FSH, P4, E2, and INH decreased significantly; and the mRNA levels of GnIH and steroidogenic factors were up-regulated in the ovarian stroma. With the termination of brooding, the ovarian activity was gradually restored: the numbers of LWFs and SYFs increased gradually; LYF began to appear; PRL in the blood decreased; FSH and E2 increased; P4 remained low; and expressions of GnIH and steroidogenic factors were down-regulated in the ovarian stroma. During the laying period, with the rapid development of follicles, the expressions of FSHR and GnIH were significantly up-regulated; GnIH expression peaked in the SY granulosa layer, while FSHR expression peaked in the F6 granulosa layer. As LYF developed and ovulation occurred, the expressions of FSHR and GnIH were significantly down-regulated, LHR expression was significantly up-regulated, the expression of GnIHR peaked in the F3 granulosa layer and then declined, PRLR expression was the lowest in the F1 granulosa layer, steroidogenic factor StAR was up-regulated, CYP19A1 was down-regulated, and 3β-HSD peaked in the F3 granulosa layer and then declined. The results indicate that GnIH/GnIHR, FSHR, LHR, and PRLR in the gonad correspond to the upstream reproductive hormones and the jointly regulated steroid hormone production and follicular development, which leads to periodic changes in ovarian activity during the laying-incubation cycle of the breeding season of Magang geese. GnIH/GnIHR might play an important regulatory role for FSHR, LHR, and PRLR in the gonads.

Atractylodes macrocephala Koidz. (AMK) and its purified polysaccharide fraction (PAMK) are known for their antioxidant, anti-inflammatory, and hepatoprotective properties, showing potential benefits for poultry liver health. This study simulated hepatic oxidative stress in late-laying hens, a physiological stage characterized by increased metabolic demands and reactive oxygen species (ROS) generation, without exogenous hepatotoxic agents. Hens were randomly assigned to three groups: control (basal diet), AMK (basal diet + 15 g/kg AMK), and PAMK (basal diet + 400 mg/kg PAMK). Both AMK and PAMK significantly reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities compared to control. Notably, PAMK showed superior efficacy, decreasing malondialdehyde (MDA) levels by 35.29% vs. 32.87% in AMK, and more effectively increasing antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Histopathological analysis revealed better-preserved liver structure and less inflammatory infiltration in PAMK-fed hens. Mechanistically, both treatments upregulated Nrf2 and downstream antioxidant genes, with stronger activation observed in the PAMK group. In vitro, PAMK reduced H2O2-induced ROS accumulation and apoptosis in primary embryonic chicken hepatocytes, effects that were attenuated by the Nrf2 inhibitor ML385. In conclusion, PAMK exerts superior hepatoprotective effects compared to crude AMK by modulating the Nrf2 pathway, mitigating oxidative stress, apoptosis, and autophagy. Future research should evaluate PAMK's long-term safety, synergistic potential with other natural antioxidants, and cost-effectiveness in poultry production.

The Lion-head goose is one of the largest goose breeds all over the word. Body weight and body size traits at 120 days of age (i.e. the slaughter age) are economically important traits, which directly affect the profit of Lion-head goose industry. However, so far few studies have explored the genetic basis of these traits. This study for the first time integrated the single-SNP genome-wide association study (GWAS) and genetic fine-mapping based on whole-genome sequencing data to investigate the genetic architecture of body weight and 11 body size traits at 120 days of age in 504 lion-head geese. Single-SNP GWAS identified three major QTL regions located on Chr18: 2,436-6,745 kb (4,210 kb), Chr18: 9,756 − 10,076 kb (320 kb) and Chr25: 4,794-4,799 kb (5 kb), which were associated with body weight, semi-diving length, pelvic width, fossil bone length and chest depth. Genetic fine-mapping of these three QTL regions revealed 16 candidate genes and 68 important SNP-trait pairs. Out of these genes, MBTD1, CEP112, RAB11FIP4, APOH, and WIPI1 were associated with body weight and other body size traits. Among these SNP-trait pairs, we found a nonsynonymous mutation (c.C463A) in the MBTD1 influencing body weight and other two body size traits. These findings will enhance our understanding of the genetic architecture of body weight and body size traits at 120 days of age, which support the application of molecular breeding on these economically important traits in Lion-head geese.

To investigate the regulatory mechanism mediated by hypothalamic OPN5 on seasonal changes in the reproductive activities of domestic geese, 60 Magang ganders in their breeding period were selected for the experiment and evenly divided into an immunization group(OPN5-IM) and a control group. On days 0, 15 and 30, ganders in the immunized group were immunized with OPN5-KLH protein vaccine, and ganders in the control were immunized with the same amount of blank emulsified vaccine. Additionally, 120 female geese were provided to stimulate the reproductive activities of male geese. The results showed that the arrangement of spermatogenic cells was disturbed, the number of sperm decreased, and the testicular weight, seminiferous tubule area, length diameter, spermatogenic epithelium thickness decreased significantly with the natural day length prolonged. Moreover, the concentration of testosterone and LH decreased significantly while PRL increased. The prolonged photoperiod significantly affected the gene expression of GnRH-I, VIP, FSHβ, FSHR, LHβ, PRL, and PRLR in ganders. Specifically, the gene expression of GnRH-I, FSHβ, and LHβ in the hypothalamus and pituitary decreased, while the gene expression of VIP, PRL, and PRLR increased. Following OPN5 immunization, the anti-OPN5 antibody titer of ganders in the OPN5-IM group was notably higher than in the control group. The testicular degeneration was severe in OPN5-IM group compared with the control, as evidenced by a significant reduction in seminiferous tubule area, length diameter, and thickness of spermatogenic epithelium in the immunized group on day 60. Additionally, the concentrations of testosterone and LH were lower in the OPN5-IM group than in the control group, whereas PRL was higher. Moreover, OPN5 immunization significantly affected the expression of GnRH-I, PRL, and PRLR. OPN5 mRNA and protein expression were higher in the immunized group, whereas TRH, DIO2, and TSHR mRNA expressions were lower. However, DIO3 mRNA and protein were up-regulated in the immunized group. In conclusion, our results indicated that the reproductive performance of Magang geese degraded from the breeding to the non-breeding period as daylight was extended. Immunization against OPN5 increased OPN5 expression and down-regulated the TSH-DIO2/DIO3 pathway, further to affect the HPG axis and accelerate the degradation of reproductive activity. Therefore, OPN5 may play an important mediating role in light-regulating seasonal reproductive degradation in Magang geese.

Shitou goose (STE) and Wuzong goose (WZE) are both characteristic goose breeds in Guangdong, China. Their growth cycle is similar, but there are huge differences in body size. One of the reasons for the difference in body size is the individual muscle mass, which is determined by myofiber development. The number of myofibers is fixed as early as the embryonic stage. Therefore, in this study, the leg muscles of 15, 23-day-old geese embryos (E15, E23), and the first day of hatching (P1) goslings of both STE and WZE were selected for analysis. Muscle tissue samples were subjected to histological sectioning and staining for morphological analysis. Differentially expressed genes (DEGs) across developmental stages were identified through systematic screening. An expression map of the identified DEGs was generated, and a gene interaction network was constructed to elucidate potential regulatory mechanisms. The results showed that the leg muscle development of STE at the embryonic development stage was superior to that of WZE. Through GO and KEGG analyses, it was found that STE was significantly more enriched in processes related to muscle development than WZE. Analysis of the gene expression profiles of STE and WZE revealed different manifestations, and it was observed that STE exhibited significantly more unique genes compared with WZE. We constructed the interaction network of myo-genes, including 77 genes in the network of STE and 17 genes in the network of WZE. We found that the unique gene interaction network in STE is more complex, suggesting that the potential regulatory environment of muscle development in STE may be more complex than that in WZE. The RT-qPCR results of nine identified myogenic genes (MYH7, MYO1F, MYOZ1, MYO5B, MYH11, ITGB8, MSTN, MFN2 and CCNB1) were consistent with the RNA-seq analysis. This study demonstrated that the developmental differences between STE and WZE originated during the embryonic stage. This study is the first to systematically compare the leg muscle development mechanisms of two goose breeds during embryonic stages. The results distinct developmental patterns and molecular regulation patterns of leg muscles between STE and WZE, providing a theoretical foundation for understanding the differences in myofiber development among different breeds.

Copy number variation (CNV) is an important type of genetic variations contributing to phenotypic differences in animals and may serve as an alternative molecular marker to single nucleotide polymorphism (SNP) for molecular breeding. We used whole-genome sequencing data to investigate the characteristic of CNVs and their associations with body weight and size traits for 504 120-day Lion-head geese. We detected 1,184,695 CNVs which consisted of 1,148,401 deletions and 36,294 duplications. Based on these CNVs, we obtained 8,043 CNV regions (CNVRs) including 7,578 deletions, 228 duplications and 237 mixeds, which covered 7.76% of the reference genome. The 81.03% of CNVRs had the length ranging from 50bp to1000bp. We filtered 8,767 high-quality genotyped CNVs (7,960 deletions and 807 duplications) to conduct the association analysis of the body weight and 11 body size traits with these CNVs. We found 42 chromosome-wide significant CNVs, among which 40 were novel, and 2 CNVs had the high linkage disequilibrium (r2>0.20) with adjacent SNPs with chromosome-wide significance. According to these significant CNVs, we annotated 47 genes. Among these genes, CEP112, TOM1L1 and STX8 simultaneously influenced body weight and other body size traits, which was worthy of further study.

The gut serves not only as digestive but also as critical immune organ, playing a vital role in maintaining the growth performance and immune function of poultry. Atractylodes macrocephala Koidz (AMK) is known for its antioxidant, anti-inflammatory and immunomodulatory properties. This study utilized a Cyclophosphamide (CTX)-induced gut injury model to explore the effects of Polysaccharide of Atractylodes macrocephala Koidz (PAMK) and the Jiawei Si-jun-zi Decoction (JSD) on alleviating gut injury and modulating immune function. The experimental results demonstrated that CTX significantly reduced the average daily gain (ADG) and antioxidant capacity of broiler chicks, disrupted intestinal barrier function, and induced gut microbiota dysbiosis. However, supplementation with PAMK and JSD significantly improved ADG, enhanced antioxidant enzyme activity, alleviated oxidative stress, and upregulated the expression of barrier-related genes such as ZO-1 and Occludin. Additionally, PAMK and JSD significantly increased anti-inflammatory cytokines, including IL-10 and TGF-β, improved gut microbiota diversity, enriched beneficial microbial populations, and restored the microbiota balance disrupted by CTX. These findings suggest that PAMK and JSD effectively mitigate CTX-induced intestinal injury by regulating the antioxidant system, strengthening intestinal barrier function, and restoring gut microbiota structure. This study provides a scientific basis for the development of safe and effective feed additives and proposes a novel strategy to reduce antibiotic use in poultry farming.

Background: Escherichia coli and Salmonella contamination in goose bath water releases endotoxins like lipopolysaccharide (LPS), compromising immunity and hindering goose farming. Objective: This study evaluated effects of dietary Bacillus subtilis and bacteriophage supplementation on water quality, carcass traits, and muscle growth in Magang geese. Method: A total of 288 geese were divided into four groups based on similarity in weight (n = 6 geese): A (basal diet); B (basal diet + bacteriophage: 5.0 × 1010 PFU/L at 1:1000 dilution); C (basal diet + Bacillus subtilis: 5.0 × 109 CFU/kg); D (basal diet + bacteriophage + Bacillus subtilis). Results: Supplementation significantly increased wing length, tibia length, and live weight at 60 days. It reduced water and plasma endotoxin levels and suppressed viable counts of Escherichia coli, Salmonella, and total bacteria in water across rearing stages. Supplementation up-regulated mRNA and protein expression of myogenic regulators (MYOD, MYOG, MYH1) and IGF-1, while down-regulating pro-inflammatory cytokines (TNF-α, IL-6), suggesting enhanced myofiber growth. Conclusion: These findings demonstrate that Bacillus subtilis and bacteriophage supplementation improves goose growth performance and immune status by modulating key genes, reducing pathogens and endotoxins, offering an eco-friendly strategy to enhance productivity and potentially reduce antibiotic dependency.

Gonadotropin-inhibitory hormone (GnIH) plays a crucial role in regulating reproduction in the hypothalamus of poultry and has been intensely investigated since its discovery. This study aimed to assess the effects of GnIH on testicular development, as well as on reproduction-related hormone release and gene expression levels in roosters. The administration of exogenous GnIH resulted in a significant reduction in testis weight, testis volume and semen quality (p < 0.05). Additionally, exogenous GnIH significantly up-regulates the expression of GnIH, and down-regulates the expression of PRL (p < 0.05). GnIH application also decreased the GnRH, vasoactive intestinal peptide (VIP) and luteinizing hormone β subunit(LHβ)gene expression levels. Meanwhile, by neutralizing the effects of endogenous GnIH through immunization, testicular development on day 150 in roosters was significantly promoted. Compared to the control condition, GnIH immunization significantly down-regulated the expression of the VIP and PRL genes (p < 0.05). In conclusion, we found that exogenous GnIH treatment inhibited testicular development, reduces PRL gene expression, and suppressed reproductive performance in roosters. Conversely, GnIH immunization down-regulated VIP and PRL genes, activates the reproductive system, and promotes the reproductive activity and testicular development of roosters.

Background Lipopolysaccharide (LPS) can induce systemic inflammation and affect the growth and development of poultry. As a kind of traditional Chinese medicine, polysaccharide of Atractylodes macrocephala Koidz (PAMK) can effectively improve the growth performance of animals and improve the immunity of animal bodies. ObjectivesThe purpose of this study was to investigate the effects of PAMK on LPS-induced inflammatory response, proliferation, differentiation and apoptosis of chicken embryonic myogenic cells. Methods We used chicken embryonic myogenic cells as a model by detecting EdU/MYHC immunofluorescence, the expression of inflammation, proliferation, differentiation-related genes and proteins and the number of apoptotic cells in the condition of adding LPS, PAMK, belnacasan (an inhibitor of Caspase1) or their combinations. Results The results showed that LPS stimulation increased the expression of inflammatory factors, inhibited proliferation and differentiation, and excessive apoptosis in chicken embryonic myogenic cells, and PAMK alleviated these adverse effects induced by LPS. After the addition of belnacasan (inhibitor of Caspase1), apoptosis in myogenic cells was inhibited, and therefore, the number of apoptotic cells and the expression of pro-apoptotic genes Caspase1 and Caspase3 were increased. In addition, belnacasan inhibited the increased expression of inflammatory factors, inhibited proliferation, differentiation and excessive apoptosis in chicken embryonic myogenic cells induced by LPS. Conclusions This study provides a theoretical basis for further exploring the mechanism of action of PAMK and exogenous LPS on chicken embryonic myogenic cells and lays the foundation for the development and application of green feed additives in animal husbandry industry.

Lactation is a unique reproductive behavior in pigeons, with the crop serving as the organ responsible for secreting pigeon milk. Both male and female pigeons can produce crop milk and rear their offspring through a division of labor. Since the time of the secretion of pigeon crop milk is different in the process of feeding the young, whether the metabolism and formation of pigeon milk use the same mechanism is a very interesting scientific question. However, the metabolic dynamics and underlying genetic mechanisms involved in the formation of pigeon crop milk remain unclear, particularly during the incubation–feeding reproductive cycle. In this study, we integrated lactation-associated metabolism and transcriptome data from the crop tissues of both male and female pigeons during the brooding and feeding stages. We mapped the changes in metabolites related to milk formation in the crop tissues during these stages. Through metabolome profiling, we identified 1413 metabolites among 18 crop tissues. During the breeding cycles, the concentrations of estrone, L-ergothioneine, and L-histidine exhibited the most dynamic changes in females. In contrast, estrone, L-anserine, 1-methylhistidine, homovanillate, oxidized glutathione, and reducing glutathione showed the most dynamic changes in males. Gender-specific differences were observed in the metabolome, with several metabolites significantly differing between males and females, many of which were correlated with cytokine binding, immunity, and cytochrome P450 activity. Using this dataset, we constructed complex regulatory networks, enabling us to identify important metabolites and key genes involved in regulating the formation of pigeon milk in male and female pigeons, respectively. Additionally, we investigated gender-associated differences in the crop metabolites of pigeons. Our study revealed differences in the modulation of pigeon crop milk metabolism between males and females and shed light on the potential functions of male and female pigeon milk in the growth, development, and immunity of young pigeons, an area that has not been previously explored. In conclusion, our results provide new insights into the metabolic regulation of pigeon crop milk formation during the brooding and breeding stages. Furthermore, our findings lay the foundation for the accurate development of artificial pigeon milk.