High albumen height by expression of GALNT9 and thin eggshell by decreased Ca2+ transportation caused high hatchability in Huainan partridge chicken.

Hatchability could be quite different among individuals of indigenous chicken breed which might be affected by the egg quality. In this study, hatchability was individually recorded among 800 forty-wk-old Huainan partridge chickens. The chickens were then divided into high and low hatchability groups (HH and LH group) with 50 birds in each group. Egg quality was further determined in the 2 groups. Eight birds from each group were selected for slaughtering and tissue, responsible for egg formation, collection for structure observation by staining and candidate gene expression by transcriptome analysis. The hatchability in HH was 100% and 61.18% in LH. The eggshell thickness and shell strength were significantly lower, while the albumen height and Haugh unit were significantly higher in HH group than those in LH group (P < 0.05). The magnum weight and index, and the expression of polypeptide N-acetylgalactosaminyltransferase 9 (GALNT9), which responsible for thick albumen synthesis, in HH group were also significantly higher than that of LH group (P < 0.05). Compared with the LH group, there were 702 differentially expressed genes (DEGs) in HH group, of which 402 were up-regulated and 300 were down-regulated. Candidate genes of calbindin 1 (CALB1) and solute carrier family 26 member 9 (SLC26A9), which regulate calcium signaling pathway so as to affect Ca2+ transportation, exhibited significant high and low expression, respectively, in HH group compared to those in LH group (P < 0.05). Therefore, indigenous chicken with high expression of GALNT9 in magnum to form thick albumen to provide more protein for embryo, while high CALB1 and low expression of SLC26A9 to decrease Ca2+ transportation so as to form a thinner eggshell and provide better gas exchange during embryo development.

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

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

Undernutrition Disrupts Cecal Microbiota and Epithelium Interactions, Epithelial Metabolism, and Immune Responses in a Pregnant Sheep Model.

Undernutrition may change cecal microbiota-epithelium interactions to influence cecal feed fermentation, nutrient absorption and metabolism, and immune function. Sixteen late-gestation Hu-sheep were randomly divided into control (normal feeding) and treatment (feed restriction) groups to establish an undernourished sheep model. Cecal digesta and epithelium were collected to analyze microbiota-host interactions based on 16S rRNA gene and transcriptome sequencing. Results showed that cecal weight and pH were decreased, volatile fatty acids and microbial proteins concentrations were increased, and epithelial morphology was changed upon undernutrition. Undernutrition reduced the diversity, richness, and evenness of cecal microbiota. The relative abundances of cecal genera involved in acetate production (Rikenellaceae dgA-11 gut group, Rikenellaceae RC9 gut group, and Ruminococcus) and negatively correlated with butyrate proportion (Clostridia vadinBB60 group_norank) were decreased, while genera related to butyrate (Oscillospiraceae_uncultured and Peptococcaceae_uncultured) and valerate (Peptococcaceae_uncultured) production were increased in undernourished ewes. These findings were consistent with the decreased molar proportion of acetate and the increased molar proportions of butyrate and valerate. Undernutrition changed the overall transcriptional profile and substance transport and metabolism in cecal epithelium. Undernutrition suppressed extracellular matrix-receptor interaction and intracellular phosphatidyl inositol 3-kinase (PI3K) signaling pathway then disrupted biological processes in cecal epithelium. Moreover, undernutrition repressed phagosome antigen processing and presentation, cytokine-cytokine receptor interaction, and intestinal immune network. In conclusion, undernutrition affected cecal microbial diversity and composition and fermentation parameters, inhibited extracellular matrix-receptor interaction and the PI3K signaling pathway, and then disrupted epithelial proliferation and renewal and intestinal immune functions. Our findings exposed cecal microbiota-host interactions upon undernutrition and contribute to their further exploration. IMPORTANCE Undernutrition is commonly encountered in ruminant production, especially during pregnancy and lactation in females. Undernutrition not only induces metabolic diseases and threatens pregnant mothers' health, but also inhibits fetal growth and development, leading to weakness or even death of fetuses. Cecum works importantly in hindgut fermentation, providing volatile fatty acids and microbial proteins to the organism. Intestinal epithelial tissue plays a role in nutrient absorption and transport, barrier function, and immune function. However, little is known about cecal microbiota and epithelium interactions upon undernutrition. Our findings showed that undernutrition affected bacterial structures and functions, which changed fermentation parameters and energy regimens, and therefore affected the substance transport and metabolism in cecal epithelium. Extracellular matrix-receptor interactions were inhibited, which repressed cecal epithelial morphology and cecal weight via the PI3K signaling pathway and lowered immune response function upon undernutrition. These findings will help in further exploring microbe-host interactions.

Effects of Clostridium butyricum on growth performance, meat quality, and intestinal health of broilers.

This study investigated the effects of Clostridium butyricum on the growth performance, meat quality and intestinal health of broilers. A total of 800 one-day-old male Arbor Acres broilers were randomly assigned to two groups with 16 replicates of 25 broilers per group and fed with a basal diet (CON) or a basal diet supplemented with 1.5 × 109 cfu/kg C. butyricum and 5 × 108 cfu/kg C. butyricum at 1-21 d and 22-42 d, respectively (CB). The results indicated that C. butyricum significantly increased the final body weight, average daily gain at 1-42 d in the growth performance of broilers (P < 0.05). Moreover, C. butyricum significantly increased a 24 h * value and pH24h value of breast meat but reduced the drip loss and shear force (P < 0.05). Regarding serum antioxidant indices, C. butyricum significantly increased the total superoxide dismutase (T-SOD) and total antioxidative capacity activities and reduced the malondialdehyde content (P < 0.05). Furthermore, the broilers in the CB demonstrated an increase in jejunal lipase and trypsin activities, villus height (VH) and VH-to-crypt depth ratio at 42 d compared with those in the CON (P < 0.05). C. butyricum also upregulated the intestinal mRNA levels of zonula occludens-1, nuclear factor erythroid 2-related factor 2 (Nrf2), SOD1 and interleukin-10 in the jejunal mucosa (P < 0.05), but it downregulated the mRNA levels of nuclear factor kappa B (NF-κB) and tumor necrosis factor-α (P < 0.05). These results indicate that C. butyricum can improve the growth performance and meat quality of broilers. In particular, C. butyricum can improve the intestinal health of broilers, which is likely to be related to the activation of the Nrf2 signaling pathway and inhibition of the NF-κB signaling pathway.

Green tea powder inclusion promoted hatchability through increased yolk antioxidant activity.

Dietary supplementation of green tea powder (GTP) changes egg quality of hens, however, whether these changes affect incubation is still unknown. This study was to compare the proteomic difference of incubated eggs from hens with GTP supplemented or not. Huainan partridge chickens (1,080) at 35 wk of age were allocated into 2 groups, one group fed basal diet (CG) and one group fed basal diet plus 1% GTP (EG). After 4 wk feeding, artificially fertilized eggs were collected for yolk cholesterol determination and incubation. During incubation, 6 embryos from each group were randomly selected in each day for yolk protein extraction and quantification. Yolk cholesterol content was significantly lower, while the hatchability was significantly higher in EG than that of the CG group (P < 0.05). Yolk protein concentration at embryonic days (ED) of 0, 2, 6, and 13 showed significant changes and were selected for proteomic analysis by 2-dimensional gel electrophoresis combined with liquid chromatography-tandem mass spectrometry. Fifty-one differentially expressed (DE) protein spots were identified among different incubation stages between CG and EG group which were mainly classified into vitellogenin, immunoglobulin, and ovoinhibitor, and occupied 45.1, 23.5, and 15.7%, respectively, to the total DE proteins. Ovotransferrin, participated in extracellular sequestering of iron ion process, was significantly lower in EG group than that of the CG group (P < 0.05). Ig light chain precursor (Immunoglobulin) exhibited higher expression at ED6 in EG group as compared with that of the CG group, and was participated in immune response related processes. Ovoinhibitor, mainly involved in protease binding activity, showed lower abundance at ED13 in EG group as compared with that of the CG group. Vitellogenin-3, showed lower expression in EG group as compared with that of the CG group, was mainly participated in lipid transportation and localization according to GO enrichment. Chickens fed diet with GTP provided eggs more antioxidant ability that increased hatchability, indicated that GTP could be considered as additive in breeding layer.

Effect of L-theanine on meat quality, muscle amino acid profiles, and antioxidant status of broilers.

This study investigated the effect of L-theanine on carcass traits, meat quality, muscle antioxidant capacity, and amino acid (AA) profiles of broilers. Three hundred 1-day-old Ross 308 male broilers were randomly allotted to five groups with six replicates. Birds were fed the basal diet or basal diet with 300, 600, 900, or 1,500 mg/kg L-theanine for 42 consecutive days. The results showed that L-theanine quadratically increased dressing percentage, eviscerated percentage, and leg muscle yield (p < .05). Meanwhile, drip loss, cooking loss, shear force, L*24h, and muscle lactate content decreased quadratically in response to dietary L-theanine supplementation (p < .05), while pH24h and muscle glycogen content were quadratically improved by L-theanine (p < .05). Notably, the contents of muscle malondialdehyde and protein carbonyl, and the activities of muscle total antioxidant capacity, catalase, and glutathione peroxidase decreased quadratically in response to dietary L-theanine supplementation (p < .05), suggesting that the oxidative stress level of muscle was decreased quadratically. Moreover, L-theanine quadratically increased the concentrations of most of muscle essential AA, nonessential AA, and flavor AA (p < .05). In conclusion, L-theanine can be used as a valuable feed additive to modulate carcass traits, meat quality, muscle antioxidant status, and AA profiles of boilers, and its optimum addition level is 600 mg/kg based on the present study.

Egg-laying and brooding stage-specific hormonal response and transcriptional regulation in pituitary of Muscovy duck (Cairina moschata).

Broodiness is an interesting topic in reproductive biology for its reduced egg production. The strong brooding trait of Muscovy duck has become a major factor restricting the development of its industry. Broody phenotype and environmental factors influencing broodiness in poultry have been extensively studied, but the molecular regulation mechanism of broodiness remains unclear. In this research, the Muscovy duck reproductive endocrine hormones and pituitary transcriptome profiles during egg-laying phases (LP) and brooding phases (BP) were studied. During BP (n = 19), prolactin (PRL) levels was higher, while progesterone (P4) and estradiol (E2) were lower as compared to ducks during their LP (n = 20) (P < 0.01). We then examined the pituitary transcriptome of Muscovy duck at the 2 reproductive stages. A total of 398 differentially expressed genes included 20 transcription factors were identified (fold change ≥ 1.5, P < 0.01). There were 109 upregulated and 289 downregulated genes at brooding phases (n = 6) compared with egg-laying phases (n = 6). Real-time quantitative PCR analysis was carried out to verify the transcriptome results. The present study suggested that neuroactive ligand-receptor interaction pathway, calcium signaling pathway, and response to steroid hormones biological process are critical for controlling broodiness in the ducks. Further analysis revealed that SHH, PTGS2, RLN3, and transcription factor AP-1 may act as central signal modulators of hormonal and behavioral regulation mechanism associated with broodiness.

NRDR inhibits estradiol synthesis and is associated with changes in reproductive traits in pigs.

Cumulus cells secreting steroid hormones have important functions in oocyte development. Several members of the short-chain dehydrogenase/reductase (SDR) family are critical to the biosynthesis of steroid hormones. NADPH-dependent retinol dehydrogenase/reductase ( NRDR), a member of the SDR superfamily, is overexpressed in pig breeds that also show high levels of androstenone. However, the potential functions and regulatory mechanisms of NRDR in pig ovaries have not been reported to date. The present study demonstrated that NRDR is highly expressed in pig ovaries and is specifically located in cumulus granulosa cells. Functional studies showed that NRDR inhibition increased estradiol synthesis. Both pregnant mare serum gonadotropin and human chorionic gonadotropin downregulated the expression of NRDR in pig cumulus granulosa cells. When the relationship between reproductive traits and single-nucleotide polymorphisms (SNPs) of the NRDR gene was examined, we found that two SNPs affected reproductive traits. SNP rs701332503 was significantly associated with a decrease in the total number of piglets born during multiparity, and rs326982309 was significantly associated with an increase in the average birth weight during primiparity. Thus, NRDR has an important role in steroid hormone biosynthesis in cumulus granulosa cells, and NRDR SNPs are associated with changes in porcine reproduction traits.

Immune Responses Induced by pVAX/TgERK7 against Toxoplasma gondii Infection in BALB/c Mice.

BACKGROUND: Toxoplasma gondii can infect all the warm-blooded vertebrates and cause serious toxoplasmosis. Extracellular signal-regulated kinase 7 in T. gondii (TgERK7) mediated the proliferation of this parasite may be a potential vaccine candidate. Thus, immune responses induced by TgERK7 were investigated in this study using a DNA vaccine strategy. METHODS: pVAX/TgERK7 plasmid was constructed and used to immunize BALB/c mice for three times with two-week intervals. The challenge and the investigation of humoral and cellular immune responses were performed at two weeks post the last immunization, and the survival times of the infected mice were daily recorded until all of them were dead. RESULTS: The innate immune response with higher concentrations of IFN-γ, TNF-α, IL2 and IL12p70 in sera (P < 0.05), and the adaptive immune responses were evoked by the DNA immunizations, including specific antibody, lymphocyte proliferation, and the CD3e+CD4+ and CD3e+CD8a+ T cell-mediated response effects. Interestingly, no significant difference was detected in their survival times among all the experimental groups of mice that were challenged with GT1 tachyzoites or PRU cysts (P>0.05). CONCLUSION: The successive immunizations with pVAX/TgERK7 can provoke the innate and adaptive immune responses of BALB/c mice, whereas the DNA vaccine-induced immunological efficacy is not sufficient for complete protection the host against T. gondii infection.

Protective effects of resveratrol against high ambient temperature-induced spleen dysplasia in broilers through modulating splenic redox status and apoptosis.

BACKGROUND: Resveratrol has been shown to prevent high ambient temperature (HT)-induced spleen dysplasia, but the mechanisms of action are not clear. This study aims to examine the hypothesis that HT-induced spleen dysplasia may be associated with HT-induced oxidative stress and apoptosis, and resveratrol may activate the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway, thus reducing oxidative stress and apoptosis. RESULTS: Results showed that HT caused spleen dysplasia in broilers, reflecting the lower relative weight of the spleen (P < 0.05). Compared with birds in a normal ambient temperature group, birds in the HT group exhibited higher (P < 0.05) malondialdehyde (MDA), protein carbonyl (PC), 8-hydroxydeoxyguanosine (8-OHdG) and Bcl-2 associated X protein (Bax) content, higher Bax, caspase-3 and caspase-9 mRNA levels, and caspase-3 and caspase-9 activity, and a higher Bax/B-cell lympoma/leukemia-2 (Bcl-2) ratio, but they exhibited lower (P < 0.05) glutathione (GSH) and Bcl-2 content, and lower Nrf2, glutathione peroxidase (Gpx), MnSOD, heme oxygenase 1, glutathione reductase (GR) and Bcl-2 mRNA levels, and lower total antioxidant capacity (T-AOC), T-SOD and catalase and maganese superoixide dismutase (CAT) activity, indicating HT-induced oxidative stress and apoptosis. Compared with birds in the HT group, birds in the HT + Res group exhibited higher (P < 0.05) GSH and Bcl-2 content, higher Nrf2, CAT, MnSOD, GR and Bcl-2 mRNA levels, and higher T-AOC, T-SOD and CAT activity, but lower (P < 0.05) MDA content, and Bax and caspase-3 mRNA levels, lower caspase-3 and caspase-9 activities, and Bax/Bcl-2 ratio, indicating that resveratrol activated the Nrf2 signaling pathway and decreased apoptosis in the spleen. CONCLUSION: Resveratrol was effective in ameliorating HT-induced spleen dysplasia in broilers through the activation of the Nrf2 signaling pathway, thereby decreasing apoptosis, suggesting that resveratrol may offer a potential nutritional strategy to protect against some HT-induced detriments. © 2018 Society of Chemical Industry.

Effect of dietary resveratrol supplementation on meat quality, muscle antioxidative capacity and mitochondrial biogenesis of broilers.

BACKGROUND: The naturally occurring polyphenol resveratrol has been acknowledged with many beneficial biological effects. The aim of this study was to evaluate the influence of dietary resveratrol supplementation on meat quality, muscle antioxidative capacity and mitochondrial biogenesis of broilers. One hundred and eighty 21-day-old male Cobb broilers were randomly assigned to two groups and fed on a 0 mg kg-1 or 400 mg kg-1 resveratrol-supplemented diet for 21 days. Then, chickens were slaughtered and pectoralis major muscle (PM) samples were collected for analysis. RESULTS: The results showed that resveratrol not only tended to increase (P < 0.10) PM pH24h but also significantly decreased (P < 0.05) PM L*45min , pH decline, drip loss and lactate content. Meanwhile, PM total antioxidative capacity and catalase activity were significantly increased (P < 0.05) by resveratrol, while malondialdehyde content was decreased (P < 0.10). Moreover, resveratrol significantly increased (P < 0.05) PM peroxisome proliferator-activated receptor γ coactivator 1α and nuclear respiratory factor 1 mRNA levels, along with increased (P < 0.05) citrate synthase activity. CONCLUSION: Resveratrol can be used as a feed additive to improve meat quality of broilers, which may be associated with improved muscle antioxidative status and mitochondrial biogenesis. © 2017 Society of Chemical Industry.

Resveratrol beneficially affects meat quality of heat-stressed broilers which is associated with changes in muscle antioxidant status.

This study was conducted to evaluate the effect of dietary resveratrol (Res) supplementation on serum parameters, meat quality and muscle antioxidant status of broilers under heat stress (HS). A total of 270 21-day-old male Cobb broilers were randomly assigned to three treatment groups with six replicates of 15 birds each. The three treatment groups were as follows: the control group, in which birds were reared at 22 ± 1°C, and the HS and HS + Res (400 mg/kg) groups, in which birds were reared at 33 ± 1°C for 10 h (08.00-18.00 h) and 22 ± 1°C for the rest of the time. Compared with birds in the control group, birds in the HS group exhibited increased serum corticosterone (CORT) and triacylglycerol contents, L*, drip loss and muscle malondialdehyde content, and decreased serum glucose content, pH24 h , muscle total antioxidant capacity (T-AOC), catalase (CAT) and glutathione peroxidase (GSH-PX) activities (P < 0.05). Compared with birds in the HS group, birds in HS + Res group exhibited increased serum glucose content, a*, pH24 h , muscle T-AOC and CAT activities, and decreased serum CORT and triacylglycerol contents, L*24 h , drip loss and muscle malondialdehyde content (P < 0.05). In conclusion, Res beneficially protects against HS-impaired meat quality of broilers through regulating muscle antioxidant status.

Effects of Caponization on Expression of Gonadotropin-Releasing Hormone-I and Gonadotropin Subunits Genes in Roosters.

We evaluated the effects of caponization on mRNA levels of gonadotropin-releasing hormone-I (GnRH-I), gonadotropin subunit and other hypothalamic and hypophyseal peptide genes in male chicken. Thirty roosters (25 d) with similar weight were equally divided into the experimental (capons) and control (sham-operated males) groups randomly. Caponization was performed at 28 days of age and birds were slaughtered at 140 days of age. Caponization resulted in increasing levels of luteinizing hormone ß (LHß) and follicle-stimulating hormone ß (FSHß) mRNA in the pituitary gland and levels of LH and FSH in serum (P<0.05 or P<0.01). There were no significant differences in levels of GnRH-I, Gonadotropin releasing hormone receptor (GnRHR), neuropeptide Y (NPY) and Proopiomelanocortin (POMC) mRNA between the two groups. Capons exhibited lower levels of follistatin (FS), estrogen receptor α (ERα) and higher levels of androgen receptor (AR) mRNA in the pituitary gland compared with sham-operated males (P<0.05). These results suggest that increased LH and FSH concentrations in serum and LHß and FSHß mRNA levels in pituitary after castration are not depended on GnRH synthesis. And changed expression of ERα, AR and FS genes in the pituitary gland may be important components of regulating gonadotropin in capons.

Follicle characteristics and follicle developmental related Wnt6 polymorphism in Chinese indigenous Wanxi-white goose.

In birds, downy feather quantity mainly affected by the follicles. Wnt6, a secreted cysteine-rich protein, plays a key role in follicular development as an intercellular signaling molecule. The present study was to investigate the follicle development and Wnt6 polymorphism in Wanxi-white geese, a Chinese indigenous breed. In total, 300 fertilized eggs were hatched. At embryonic stage and on early birth goslings, the diameter and density of follicles from different sites were examined after sectioning and staining. The results showed that the diameter of primary feather follicles in thorax, venter, dorsum and flank had no difference at embryonic stage. In contrast, after birth, thorax and ventral feather follicles had greater diameter than those on dorsum and flank. Similarly, the primary feather follicle density was higher in thorax and venter than in dorsum and flank at embryonic stage. The secondary feather follicle diameter in flank was greater than that in other sites examined. The secondary follicle showed lush growth in E27 with thickest in ventral and thorax. Overall, follicle formed consistently in dorsal and flank, and follicle in thorax and ventral formed in another consistent way. The polymorphism study showed 2 single nucleotide polymorphisms of Wnt6 and 3 genotypes identified. Sequencing revealed two nucleotide transitions, T451C and A466G, which were synonymous mutations causing codons for aspartate and lysine to change from GAU to GAC and from AAA to AAG, respectively. This information about follicle development and Wnt6 polymorphisms would provide potential utilization in marker-assisted selection program for down feather selection.