Significant differences in reproductive performance exist between meat-type ducks (e.g., Qiangying Duck, QD) and laying-type ducks (e.g., Shaoxing Duck, SD). The molecular mechanisms underlying these differences, particularly concerning ovarian development and function, remain incompletely understood. This study aimed to comprehensively characterize the ovarian transcriptomes of these two duck types, focusing on differential gene expression and post-transcriptional regulatory events. We performed an integrated full-length transcriptome analysis of ovarian tissues from these two breeds using PacBio SMRT and Illumina sequencing. Bioinformatic analyses, including functional annotation, differential expression analysis, and the identification of APA events, were used. We discovered substantial breed-specific differences in alternative polyadenylation (APA), with SD ducks exhibiting significant 3'UTR shortening in 3799 genes and 3'UTR lengthening in 1626 genes compared to QD. The integrated analysis of differential gene expression and APA events highlighted key genes related to steroid hormone synthesis (HMGCS1, DHCR24), lipid metabolism (SCD), signal transduction (HRAS), and antioxidant defense (SOD1). The functional enrichment implicated critical pathways such as mitochondrial energy metabolism, oxidative phosphorylation, and fatty acid degradation. Our study provides a comprehensive atlas of post-transcriptional regulation in the duck ovary and reveals APA as a crucial process of gene regulation. APA may contribute to the differential ovarian function and egg-laying capacity between meat and laying ducks, thus offering valuable targets for genetic selection.

Thyme essential oil (TEO), a phytogenic feed additive extracted from Thymus vulgaris L., has been shown to enhance poultry performance; however, information regarding its effects in late-phase laying hens remains limited. This study evaluated the effects of dietary TEO supplementation on laying performance, antioxidant status, intestinal morphology, and cecal microbiota in late-phase Hy-Line Brown hens. A total of 160 hens were randomly assigned to four dietary treatments containing 0, 100, 300, or 500 mg/kg TEO and fed the experimental diets for 42 d. Dietary TEO supplementation significantly increased egg production compared with the control group (P < 0.05). Haugh unit values were higher in TEO-treated groups during days 22 to 42 (P < 0.05). Supplementation with 300 and 500 mg/kg TEO increased serum total antioxidant capacity (T-AOC) and the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), while decreasing malondialdehyde (MDA) concentrations (P < 0.05). Villus height and the villus height-to-crypt depth ratio in the jejunum and ileum were improved in TEO-fed hens (P < 0.05). Cecal microbiota analysis conducted in the control and TEO 300 mg/kg groups showed increased microbial richness and altered community composition following TEO supplementation, characterized by a higher relative abundance of Bacteroidota and a lower relative abundance of Bacillota. Collectively, these results indicate that dietary TEO supplementation improves laying performance and antioxidant status and modulates intestinal morphology and cecal microbial structure, suggesting its potential as a nutritional strategy to support health and productivity in aging laying hens.

Bamboo leaf flavonoids (BLFs) possess antioxidant and anti-inflammatory activities; however, their effects in aged laying hens remain unclear. This study investigated the effects of dietary BLF supplementation on production performance, egg quality, and liver health in aged laying hens. The results showed that compared with the control group, BLF significantly improved albumen height, yolk weight, and Haugh units. Histological examination showed that aged laying hens exhibited hepatic steatosis and vacuolar degeneration, whereas BLF supplementation alleviated these pathological changes. In addition, serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were significantly reduced in hens fed BLF, indicating that liver cell damage had been alleviated. BLF supplementation increased the hepatic glutathione peroxidase (GSH-Px) and total superoxide dismutase (T-SOD) activities while decreasing the malondialdehyde (MDA) levels, suggesting enhanced antioxidant capacity. Network pharmacology analysis identified major flavonoid components (quercetin, kaempferol, and luteolin) and inflammation-related targets, including IL-6, TNF, and IL-1β. Molecular docking analysis demonstrated strong binding affinities between BLF active components and these key inflammatory targets. Consistently, Western blot analysis showed that BLF reduced the expression of NF-κB, IL-6, and TNF-α in the liver. In conclusion, dietary BLF supplementation improved egg quality, enhanced hepatic antioxidant capacity, and alleviated liver inflammation in aged laying hens. These beneficial effects may be associated with the regulation of inflammatory signaling pathways, highlighting the potential of BLF as a functional feed additive.

Based on transcriptomic and metabolomic analyses, this study investigates the molecular mechanisms underlying meat flavor precursor differences in breast muscle between two duck lines (AB and DD) of Jinling White duck. At 49 days of age, compared with the faster-growing DD line, the slower-growing AB line exhibited higher pH value and higher fatty acid content in breast muscle. Integrated omics analysis identified 610 differentially expressed genes and 139 differential metabolites, highlighting key pathways such as glycerophospholipid metabolism, arachidonic acid metabolism, and linoleic acid metabolism. Key genes (PCYT1B, PLA2G12B) and metabolites (e.g., phosphatidylcholine) were identified as crucial for flavor precursors formation. This study provides insights into flavor regulation and supports genetic improvement for duck meat quality.

Age-related hepatic metabolic dysfunction significantly impairs the health and productivity of laying hens. Puerarin (Pue), a natural isoflavone, exhibits diverse pharmacological activities relevant to liver and gut health. Our previous work demonstrated that dietary supplementation with Pue improved laying performance and egg quality, while reducing the feed conversion ratio in aged laying hens. Building on these findings, we employed an integrated multi-omics approach to investigate whether Pue exerts hepatoprotective effects by restoring gut-liver axis homeostasis, thereby supporting liver function and potentially extending the production performance of aged laying hens. Pue supplementation significantly ameliorated hepatic pathological changes, including vacuolar degeneration, lipid accumulation, fibrosis, and apoptosis. Additionally, Pue reduced malondialdehyde levels and enhanced the activities of total antioxidant capacity, glutathione peroxidase, and catalase in the liver. Transcriptomic and serum metabolomic analyses revealed that Pue upregulated CYP7B1 and downregulated CYP7A1, thereby altering bile acid profiles without affecting total bile acid levels. Molecular dynamics simulations further demonstrated that Pue exhibits a stronger binding affinity to CYP7B1 than to CYP7A1. Although Pue treatment did not significantly alter the α-diversity and β-diversity of the gut microbiota, it significantly increased the abundance of Rikenellaceae_RC9_gut_group and enhanced butyric acid production, which in turn elevated the expression of intestinal tight junction proteins (Claudin-1 and Claudin-3). Multi-omics correlation analysis confirmed the regulatory network between the gut and liver. Pue enhances hepatic health in aged laying hens by modulating bile acid metabolism and altering gut microbiota composition, primarily through gut-liver axis regulation as revealed by integrated multi-omics analyses.

Although docosahexaenoic acid (DHA) enrichment in eggs has been extensively studied in laying hens, research on DHA-fortified eggs in quails remains limited. This study evaluated the effects of graded levels of Schizochytrium algae powder (SAP) on production performance, egg quality, egg DHA enrichment and fatty acid composition, and related gene expression responsible for DHA absorption and transport in yellow-feathered laying quails. A total of 960 birds were randomly assigned to four dietary groups (0%, 0.4%, 0.8%, or 1.2% SAP) for an eight-week trial, with each group consisting of six replicates of forty quails each. A quadratic response was observed for egg production and egg mass (P < 0.05), with the 0.4% SAP group higher than the control group (P < 0.05). A significant decreasing linear trend in mortality was observed with increasing SAP levels (P < 0.05). Egg yolk color responded linearly and quadratically to dietary SAP at both 4 and 8 weeks (P < 0.05), with all supplemented groups exhibiting higher values than the control (P < 0.05). DHA content in whole egg and yolk exhibited linear and quadratic increases with SAP supplementation at all timepoints (P < 0.05), resulting in higher levels than the control in all SAP-treated groups (P < 0.05) and plateauing at the 0.8% inclusion level. Moreover, SAP supplementation linearly elevated total omega-3 polyunsaturated fatty acid content and the omega-3/omega-6 ratio, while linearly reducing γ-linolenic acid and arachidonic acid concentrations in yolk (P < 0.05). Transcriptional analysis revealed linear upregulation of key genes involved in DHA absorption and transport in the duodenum, jejunum, and liver in response to SAP supplementation (P < 0.05). These findings demonstrate that dietary supplementation with SAP quadratically increased production performance, improved yolk color, enriched egg DHA content, elevated the omega-3/omega-6 ratio, and modulated the expression of genes involved in DHA absorption and transport. Collectively, this study provides an effective strategy for developing DHA-enriched quail eggs, with an optimal dietary SAP inclusion range of 0.4%-0.8%.

The gut-ovary axis involves a complex interplay of various physiological and molecular mechanisms, which significantly impact poultry production and health. This study investigated the effects of betaine (Bet) on the gut-ovary axis of laying hens in aged laying hens. A total of 108 Hy-Line Brown hens, aged 500 days, were randomly divided into three groups (n = 36 per group) and fed diets containing 0, 1000, and 3000 mg/kg of Bet (designated as CON, l-Bet, and H-Bet, respectively) over a 42-day trial. The results indicated that dietary supplementation with Bet improved laying performance. Specifically, H-Bet Supplementation increased villus height (VH) and villus height/crypt depth ratio (VH/CD), and up-regulated the expression of Claudin-1 in the jejunal and ileal mucosa. Additionally, H-Bet enhanced the richness of Bacteroidetes and reduced Firmicutes/Bacterodietes ratio. LEfSe analysis revealed significant enrichment Eubacteriaceae, Merdibacter, Anaerorhabdus_furcosa_group, Syntrophococcus, and Clostridium_innocuum_group in Bet group. Transcriptome sequencing of small yellow follicles (SYFs) showed significant up-regulation of ATP6 and down-regulation of EGR1. KEGG enrichment analysis indicated that H-Bet influenced oxidative phosphorylation, peroxisome, and other pathways, with GESA was primarily enriched in oxidative phosphorylation, and MAPK signaling pathway. Furthermore, H-Bet supplementation increased SOD, CAT, Nrf2, NQO-1, and HO-1 expression in the jejunum, while only HO-1 expression was up-regulated in the ileum. In the ovary, H-Bet differentially affected GPX, and CAT expression. These results demonstrate that dietary supplementation with Bet improves intestinal and ovarian health in aged laying hens, likely due to enhanced antioxidant capacity and improved intestinal morphology.

China boasts a rich diversity of indigenous duck species, some of which exhibit desirable economic traits. Here, we generated transcriptome sequencing datasets of breast muscle tissue samples from 1D of four groups: Pekin duck pure breeding group (P), Jinling White duck breeding group (J), P ♂ × J ♀ orthogonal group (PJ) and J ♂ × P ♀ reciprocal-cross group (JP) (n = 3), chosen based on the distinctive characteristics of duck muscle development during the embryonic period. We identified 5053 differentially expressed genes (DEGs) among the four groups. Network prediction analysis showed that ribosome and oxidative phosphorylation-related genes were the most enriched, and muscular protein-related genes were found in the 14-day-old embryonic group. We found that previously characterized functional genes, such as FN1, AGRN, ADNAMST3, APOB and FGF9, were potentially involved in muscle development in 14-day-old embryos. Functional enrichment analysis suggested that genes that participated in molecular function and cell component and key signaling pathways (e.g., hippo, ribosome, oxidative phosphorylation) were significantly enriched in the development of skeletal muscle at 14 days of embryonic age. These results indicate a possible role of muscle metabolism and myoglobin synthesis in skeletal muscle development in both duck parents and hybrids.

The Jinling White duck represents a newly developed breed characterized by a rapid growth rate and a superior meat quality, offering significant economic value and research potential; however, the genetic basis underlying their body weight traits remains less understood. Here, we performed whole-genome resequencing for 201 diverse Jinling White male ducks and conducted population genomic analyses, suggesting a rich genetic diversity within the Jinling White duck population. Equipped with our genomic resources, we applied genome-wide association analysis for body weight on birth (BWB), body weight on 1 week (BW1), body weight on 3 weeks (BW3), body weight on 5 weeks (BW5) and body weight on 7 weeks (BW7) using four statistical models. Comparative studies indicated that factored spectrally transformed linear mixed models (FaST-LMM) demonstrated the most superior efficiency, yielding more results with the minimal false positives. We discovered that PUS7, FBXO11, FOXN2, MSH6 and SLC4A4 were associated with BWB. RAG2 and TMEFF2 were candidate genes for BW1, and STARD13, Klotho, ZAR1L are likely candidates for BW3 and BW5. PLXNC1, ATP1A1, CD58, FRYL, OCIAD1 and OCIAD2 were linked to BW7. These findings provide a genetic reference for the selection and breeding of Jinling White ducks, while also deepened our understanding of Growth and development phenotypic in ducks.

Heat stress is an important factor affecting poultry production; birds have a range of inflammatory reactions under high-temperature environments. Curcumin has anti-inflammatory and antioxidant effects. The purpose of this experiment was to investigate the effect of dietary curcumin supplementation on the liver transcriptome of laying hens under heat stress conditions. In the animal experiment, a total of 240 Hy-Line brown hens aged 280 days were divided randomly into four different experimental diets with four replicates, and each replicate consisted of 15 hens during a 42-D experiment. The ambient temperature was adjusted to 34 ± 2 °C for 8 h per day, transiting to a range of 22 °C to 28 °C for the remaining 16 h. In the previous study of our lab, it was found that supplemental 150 mg/kg curcumin can improve production performance, antioxidant enzyme activity, and immune function in laying hens under heat stress. To further investigate the regulatory mechanism of curcumin on heat stress-related genes, in total, six samples of three liver tissues from each of 0 mg/kg and 150 mg/kg curcumin test groups were collected for RNA-seq analysis. In the transcriptome analysis, we reported for the first time that the genes related to heat stress of mRNA, such as HSPA8, HSPH1, HSPA2, and DNAJA4, were co-expressed with lncRNA such as XLOC010450, XLOC037987, XLOC053511, XLOC061207, and XLOC100318, and all of these genes are shown to be down-regulated. These findings provide a scientific basis for the possible benefits of dietary curcumin addition in heat-stressed laying hens.

To investigate the effect of genetic selection on meat quality in ducks, twenty of each fast growth ducks (LCA) and slow growth ducks (LCC) selected from F6 generation of Cherry Valley ducks (♂) x Liancheng white ducks (♀) were analyzed for carcass characteristics, meat quality (physicochemical and textural characteristics), amino acid and fatty acid profiles at 7 weeks. Results showed that live body weight, slaughter weight, eviscerated yield and abdominal fat percentage of LCA were significantly higher than those in LCC ducks (P < 0.01). Moreover, the average area and diameter of myofiber were larger in LCA than LCC ducks (P < 0.01). The breast and thigh muscles of LCA exhibited significantly lower water holding capacity and thermal loss compared with LCC ducks (P < 0.01). In addition, the content of nonessential amino acids (Glu, Asp and Arg) in breast muscles and Asp, Ser, Thr and Met in thigh muscles was higher in LCC than LAA ducks (P < 0.05). The proportion of polyunsaturated fatty acids (PUFA) in breast muscles of LCC was higher than LCA ducks (P < 0.05). However, the content of saturated fatty acids (SFA) in breast and thigh muscles of LCA was higher compared with LCC ducks (P < 0.05).The proportion of monounsaturated fatty acids (MUFA) in thigh muscles was significantly higher in LCC compared with LCA ducks (P < 0.01). Finally, multiple traits were evaluated by applying principal component analysis (PCA) and the results indicated that PUFA and SFA in breast muscles of LCA played important roles in meat quality, followed by Warner-Bratzler shear force (WBSF) and MUFA. However, water holding capacity (WHC) had a dominant effect in meat quality of thigh muscles in both LCA and LCC ducks.

The aim of this study was to investigate the effects of puerarin (Pue), a phytoestrogen, on the production performance, egg quality, endocrine hormones, antioxidant capacity, and intestinal morphology in aged laying hens. A total of 180 Hy-Line Brown hens aged 480 d were randomly divided into 4 groups (n = 45 per group) and fed 0, 200, 400, and 800 mg/kg of Pue (Con, L-Pue, M-Pue, and H-Pue, respectively) during a 42-d experiment. Compared with the Con treatment, supplementation with H-Pue improved laying performance and egg quality by significantly increasing egg production, average egg weight, albumen height, yolk weight, and Haugh unit (P < 0.05) while decreasing the feed conversion ratio (P < 0.05). A diet supplemented with H-Pue significantly decreasing serum total triglycerides, total cholesterol, and low-density lipoprotein cholesterol, alanine aminotransferase (P < 0.05), and significantly increasing serum levels of follicle-stimulating hormone, luteinizing hormone and progesterone (P < 0.05). Antioxidant activity was improved by significantly increasing the activity of total antioxidant capacity, glutathione peroxidase and catalase but decreasing malondialdehyde levels in serum, jejunum, and ileum (P < 0.05), and superoxide dismutase activity exhibited a significantly increase in the jejunum and ileum (P < 0.05). Villus height and the ratio of villus height to crypt depth (P < 0.05) were significantly increased in the jejunum and ileum. In the jejunal and ileal mucosa, the three treatment groups increased the mRNA expression levels of Claudin-1 and Claudin-2 compared with Con (P < 0.05), and no significant effect was observed on the expression of Occludin and ZO-1. The results showed that dietary supplementation with Pue could improve the laying performance, egg quality, antioxidant capacity, hormonal profile, and intestinal morphology of aged laying hens.

OBJECTIVE:The objective of this study was to investigate the regulation relationship of Teneleven translocation 1 (Tet1) in DNA demethylation and the proliferation of primordial germ cells (PGCs) in chickens.METHODS:siRNA targeting Tet1 was used to transiently knockdown the expression of Tet1 in chicken PGCs, and the genomic DNA methylation status was measured. The proliferation of chicken PGCs was detected by flow cytometry analysis and cell counting kit-8 assay when activation or inhibition of Wnt4/β-catenin signaling pathway. And the level of DNA methylation and hisotne methylation was also tested.RESULTS:Results revealed that knockdown of Tet1 inhibited the proliferation of chicken PGCs and downregulated the mRNA expression of Cyclin D1 and cyclin-dependent kinase 6 (CDK6), as well as pluripotency-associated genes (Nanog, PouV, and Sox2). Flow cytometry analysis confirmed that the population of PGCs in Tet1 knockdown group displayed a significant decrease in the proportion of S and G2 phase cells, which meant that there were less PGCs entered the mitosis process than that of control. Furthermore, Tet1 knockdown delayed the entrance to G1/S phase and this inhibition was rescued by treated with BIO. Consistent with these findings, Wnt/β-catenin signaling was inactivated in Tet1 knockdown PGCs, leading to aberrant proliferation. Further analysis showed that the methylation of the whole genome increased significantly after Tet1 downregulation, while hydroxymethylation obviously declined. Meanwhile, the level of H3K27me3 was upregulated and H3K9me2 was downregulated in Tet1 knockdown PGCs, which was achieved by regulating Wnt/β-catenin signaling pathway.CONCLUSION:These results suggested that the self-renewal of chicken PGCs and the maintenance of their characteristics were regulated by Tet1 mediating DNA demethylation through the activation of Wnt4/β-catenin signaling pathway.

OBJECTIVE:The objective of this study was to identify candidate genes that play important roles in skeletal muscle development in ducks. METHODS:In this study, we investigated the transcriptional sequencing of embryonic pectoral muscles from two specialized lines: Liancheng white ducks (female) and Cherry valley ducks (male) hybrid Line A (LCA) and Line C (LCC) ducks. In addition, prediction of target genes for the differentially expressed mRNAs was conducted and the enriched gene ontology (GO) terms and Kyoto encyclopedia of genes and genomes signaling pathways were further analyzed. Finally, a protein-to-protein interaction network was analyzed by using the target genes to gain insights into their potential functional association. RESULTS:A total of 1,428 differentially expressed genes (DEGs) with 762 being up-regulated genes and 666 being down-regulated genes in pectoral muscle of LCA and LCC ducks identified by RNA-seq (p<0.05). Meanwhile, 23 GO terms in the down-regulated genes and 75 GO terms in up-regulated genes were significantly enriched (p<0.05). Furthermore, the top 5 most enriched pathways were ECM-receptor interaction, fatty acid degradation, pyruvate degradation, PPAR signaling pathway, and glycolysis/gluconeogenesis. Finally, the candidate genes including integrin b3 (Itgb3), pyruvate kinase M1/2 (Pkm), insulinlike growth factor 1 (Igf1), glucose-6-phosphate isomerase (Gpi), GABA type A receptorassociated protein-like 1 (Gabarapl1), and thyroid hormone receptor beta (Thrb) showed the most expression difference, and then were selected to verification by quantitative realtime polymerase chain reaction (qRT-PCR). The result of qRT-PCR was consistent with that of transcriptome sequencing. CONCLUSION:This study provided information of molecular mechanisms underlying the developmental differences in skeletal muscles between specialized duck lines.

In this study, we aimed to better understand the difference between the functions of the two types of granulosa cells and sought to discover more key genes involved in follicle development and follicle selection. Herein, we separately collected pre-hierarchical follicle granulosa cells (PHGCs) and preovulatory follicle granulosa cells (POGCs) for RNA extraction; the transcriptomes of the two groups were compared via RNA-seq. A total of 5273 differentially expressed genes (DEGs) were identified between the PHGCs and POGCs; 2797 genes were up-regulated and 2476 were down-regulated in the PHGCs compared with the POGCs. A qPCR analysis confirmed that the expression patterns of 16 randomly selected DEGs were highly consistent with the RNA-seq results. In the POGCs, many of the genes with the most significant increase in expression were related to steroid hormone synthesis. In addition, the genes with the most significant decline in expression, including AMH and WT1, were related to the inhibition of steroid hormone synthesis. These results suggest that steroid hormones play a key role in follicle development. Furthermore, a Gene Ontology (GO) analysis revealed that these DEGs were mainly involved in the primary metabolic process, the carbohydrate metabolic process, the cellular process, ribosomes, the cytoplasm, and intracellular processes. A Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the DEGs were mainly enriched in steroid biosynthesis, the cell cycle, ribosomes, the TGF-beta signaling pathway, focal adhesion, and so on. We also observed the morphology of the follicles at different developmental stages, and the results showed that the thickness of the granular layer of the small yellow follicles (SYFs) decreased significantly with further development. In addition, we also found that the thickness of the granulosa layer of hens over 300 days old was significantly lower than that of 200-day-old hens. In short, these data indicate that the tissue morphology and function of granulosa cells change throughout follicle development.

This study was conducted to evaluate the effect of licorice and rutin on production performance, egg quality, and mucosa antioxidant levels in Chinese yellow quail. A total of 240 Chinese Yellow Quail (400-day-old) were randomly distributed into 5 groups: the Control group, fed with a basic diet; the LR1 group, fed with basal diet supplemented with 300 + 100 mg licorice and rutin mixture/kg diet; the LR2 group, fed with basal diet supplemented with 300 + 200 mg licorice and rutin mix-ture/kg diet; the LR3 group, fed with basal diet supple-mented with 600 + 100 mg licorice and rutin mixture/kg diet and the LR4 group, fed with basal diet supplemented with 600 + 200 mg licorice and rutin mixture/kg diet. Compared with the control, supplementation with the lic-orice and rutin mixture improved the laying rate and egg-shell thickness whereas decreased the feed conversion ratio of quails. Moreover, dietary supplementation with the licorice and rutin mixture improved the antioxidant capacity by increasing the activity of the superoxide dis-mutase (SOD) level and decreasing the concentration of malondialdehyde (MDA) in the jejunal mucosa. The lico-rice and rutin mixture altered the composition of intesti-nal microbiota by influencing the relative abundances of Bacteroidetes and Bacteroides. The relative abundances of the Bacteroidetes were significantly related to the lay-ing rate of quails. In addition, the mixture of licorice and rutin was also effective in reducing the relative abundance of intestinal Proteobacteria and Enterobacter in quails, reducing the accumulation of antibiotic-resistance genes. The results revealed that supplementation of licorice and rutin mixture to the diet improved production perfor-mance, egg quality, and antioxidant capacity and modi-fied the composition of intestinal microbiota in quails. This study provides a reference for Chinese herbal addi-tives to promote production performance by modulating quail gut microbes.

旨在研究甘草和芦丁配伍使用对产蛋后期海兰褐壳蛋鸡生产性能、蛋品质、血清激素和抗氧化水平、肠黏膜抗氧化水平的影响.选取产蛋数相近的380日龄海兰褐壳蛋鸡300只,随机分为5组,每组3个重复,每个重复20只.Ⅰ组为对照组,仅饲喂基础日粮;Ⅱ、Ⅲ、Ⅳ、Ⅴ组为试验组,分别在饲喂基础日粮的基础上添加甘草+芦丁(300 mg/kg+100.mg/kg、300 mg/kg+200 mg/kg、600 mg/kg+100 mg/kg、600 mg/kg+200 mg/kg).预试期7d,正试期42d.结果表明,与对照组相比,在试验后3周,Ⅲ组和Ⅴ组产蛋率均显著提高(P＜0.05).V组的平均蛋重较对照组有极显著提高(P＜0.01).各试验组的料蛋比较对照组均有极显著下降(P＜0.01).在试验第6周,Ⅲ组和Ⅴ组蛋形指数和蛋壳厚度较对照组均有极显著提高(P＜0.01).在血清激素水平方面,试验组与对照组相比,Ⅴ组血清中雌二醇(E2)和孕酮(P4)的含量均有显著增加(P＜0.05);Ⅲ组和Ⅴ组血清中促卵泡素(FSH)的含量均有极显著增加(P＜0.01);在抗氧化水平方面,与对照组相比,Ⅴ组血清中和空肠黏膜中的丙二醛(MDA)水平均有极显著下降(P＜0.01);Ⅲ组和Ⅴ组血清中超氧化物歧化酶(SOD)活性均显著升高(P＜0.05);Ⅲ组和Ⅴ组空肠黏膜中过氧化氢酶(CAT)的活性均有极显著升高(P＜0.01).由此表明,甘草+芦丁以600 mg/kg+200 mg/kg的添加剂量效果最佳,从经济成本方面考虑,甘草+芦丁以300mg/kg+200 mg/kg的添加剂量更为适宜.

[Objectives]This paper aimed to study the biological function of WNT6 gene in the development of layer follicles and its mechanism. [Methods]300 day-old Hyline-brown laying hens were used as the research object. The expression characteristics of WNT6 mRNA in different tissues were detected. At the same time, the chicken follicular granulosa cells cultured in vitro were knocked down and overexpressed the WNT6 gene, and then the cell proliferation was detected by CCK-8. The progesterone content in the cell culture medium was detected with ELISA,and the expression of FSHR,StAR,CYP11A1 and other genes were detected by RT-qPCR. FSH concentration gradient was set up to treat in vitro layer follicular granulosa cells to study the effect of FSH on the expression of WNT6 and WNT pathway-related genes. [Results]WNT6 mRNA was specifically expressed in the granulosa cells of layer follicles, and had the highest expression level in the granulosa cells of the small yolk follicles at the critical period of follicular selection. Compared with the control group, overexpression of WNT6 significantly promoted the proliferation of granulosa cells（P＜0.01）,extremely significantly increased the synthesis of progesterone in granulosa cells（P＜0.01）,and significantly increased the expression levels of FSHR,CYP11A1,StAR,CYP19A1 and HSD3B1 genes（P＜0.05）. On the contrary, after knocking down WNT6 granulosa cell proliferation was inhibited（P＜0.01）,progesterone synthesis was extremely significantly reduced（P＜0.01）,and the expression levels of FSHR,CYP11A1,StAR,CYP19A1 and HSD3B1 genes were significantly reduced（P＜0.05）;at the same time, FSH promoted WNT6 gene expression in a dose-dependent manner（P＜0.05）. FSH significantly increased the expression level of LRP1 gene in granulosa cells（P＜0.05）and significantly reduce the expression of FOXO1 gene（P＜0.01）. [Conclusions]WNT6 was specifically expressed in granulosa cells of layer hens, and its expression level was regulated by FSH. WNT6 promoted granulosa cell proliferation and steroid hormone synthesis, and increased the expression level of FSHR gene in granulosa cells. WNT6 cooperated with FSH to promote follicle development and regulate follicular selection in laying hens.

[目的]本试验旨在研究c-myc基因在鸡卵泡上的表达及卵泡刺激素(FSH)对其的诱导作用,为明确c-myc在鸡卵泡发育过程中的相关机制提供理论基础.[方法]体外分离鸡小白卵泡(SWF)、大白卵泡(LWF)、小黄卵泡(SYF)、F4和F1卵泡颗粒层和膜层,检测c-myc mRNA和蛋白的表达;应用50 ng?mL-1 FSH处理小黄卵泡36 h,测量卵泡颗粒层的厚度和密度,检测颗粒层和膜层c-myc、标记基因和周期相关基因的表达;体外分离、培养小黄卵泡颗粒细胞,预培养16 h,用siRNA干扰c-myc 24 h后,加入50 ng?mL-1 FSH处理24 h,检测c-myc mRNA的表达.[结果]c-myc mRNA在等级前卵泡的颗粒层和膜层的表达水平都显著高于排卵前卵泡,卵泡的颗粒层和膜层上都有c-Myc蛋白表达.与对照组相比,FSH处理后,小黄卵泡颗粒层厚度增加约25.5％(P<0.05),密度增加约27.8％(P<0.01).在小黄卵泡颗粒层上,FSH降低了c-myc和类固醇激素合成急性调节蛋白(star)mRNA的表达水平(P<0.05),提高了细胞增殖抗原(pcna)和周期蛋白D2(ccnd2)mRNA的表达水平(P<0.01);在卵泡膜层上,FSH提高了c-myc和pcna mRNA的表达水平(P<0.05),极显著提高了ccnd2和star mRNA的表达水平(P<0.01).FSH能提高c-myc敲减后颗粒细胞c-myc mRNA的表达水平(P<0.05).[结论]FSH能诱导c-myc在鸡颗粒细胞中的表达,推测c-myc与体外培养的鸡小黄卵泡颗粒细胞的终端分化有关.

【Objective】This study was amied to obtain the full-length transcriptome database of granulosa cells of small yellow follicle（SYFG）,and provide references for further exploring the internal molecular regulation of chicken follicular development．【Method】The SYFG of Hy-Line variety Brown was sequenced using PacBio high-throughput sequencing platform,and the fulllength transcriptome sequence was finally obtained by filtering,clustering and correction.Bioinformatics analysis software was used to compare the full-length transcriptome data for function annotation,transcription factor annotation,coding sequence（CDS）prediction,long noncoding RNA（lncRNA）prediction and screening,simple sequence repeats（SSR）detecting and alternative splicing（AS）,and alternative polyadenylation（APA）analysis．【Result】A total of52 311full-length transcripts of SYFG of Hy-Line variety Brown were obtained,and the length was mainly distributed in 1-3 500bp.By comparing with GO,KEGG,COG,NR,Swiss-Prot,and Pfam databases,the full-length transcriptomes were annotated,of which 26 525full-length transcriptomes were annotated in GO database.The KEGG database annotated 25 233full-length transcriptomes.The COG database annotated 31 303full-length transcriptomes.The NR database annotated 34 284full-length transcriptomes.The Swiss-Prot database annotated 30 701full-length transcriptomes.The Pfam database annotated 24 622full-length transcriptomes.In addition,559transcription factor,40 944CDS,14 699lncRNAs,7types of SSR,28 423 AS,and 2 747 APA events were identified or predicted．【Conclusion】 This study obtained the full-length transcriptome sequencing data of SYFG of chicken,which improved the number and length of transcripts,perfected the functional annotation of transcripts,analyzed the type of AS and APA,and revealed the complexity of transcriptome,which could provide data support to further analyze the molecular regulatory mechanism of chicken follicular development from the transcriptome level.