Animal Bioscience最新文献

Objective: Post-hatching myogenesis is a critical determinant of meat yield and quality, with potential regulatory roles of specific genes remaining underexplored in Muscovy ducks (Cairina moschata). This study aimed to identify hub genes governing post-hatching myogenesis through transcriptomic profiling .

Methods: Three white-feathered male Muscovy ducks at 1-day-old (1D) and 80-day-old (80D) were selected, respectively. Following humane euthanasia, the left leg muscles were collected for subsequent RNA extraction, library construction, genome alignment, and transcriptome sequencing. Differential gene expression analysis was performed using DESeq2 (ver. 1.16.1), with significant differentially expressed genes (DEGs) selected under the thresholds of |log2FC|>1 and p-value<0.05. Subsequent functional characterization included enrichment analyses (Gene Ontology, KEGG, and PANTHER pathways) implemented through DAVID and KOBAS, followed by protein-protein interaction network modeling via STRING. Topological analysis with CytoHubba further pinpointed hub genes functionally linked to myogenesis.

Results: Totally 1,683 DEGs were identified between 80D and 1D muscles, including 865 upregulated and 818 downregulated genes . Totally ten hub genes, such as CD3E, ITK, COL4A6, and IVD, were prioritized as key regulators of myogenesis . Functional analysis revealed their enrichment in L-leucine catabolic processes and fatty acid β-oxidation . Pathway mapping further associated these genes with glycine/serine/threonine metabolism, and branched-chain amino acid degradation .

Conclusion: This study delineates a molecular framework for post-hatching myogenesis in Muscovy ducks, highlighting ten hub genes that orchestrate myogenesis through metabolic reprogramming . These findings advance genetic strategies for improving poultry meat production and quality .

Objective: This study aimed to investigate the effect of different levels of phytase supplementation on growth performance parameters, nutrient digestibility, amino acid digestibility, and blood inositol concentration in weanling piglets that fed corn-soybean meal diet.

Methods: Weanling piglets were allocated to one of the five feeding treatments: control, a corn-soybean meal diet; dietary supplementation of 500 FTU/kg phytase; dietary supplementation of 750 FTU/kg phytase; dietary supplementation of 1,000 FTU/kg phytase; dietary supplementation of 1,500 FTU/kg phytase. The experiment had two feeding phases (phase 1, d 1 to 21; phase 2, d 22 to 42) to clarify effects of dietary phytase supplementation.

Results: The final body weight, average daily gain, and gain-to-feed ratio in the whole experimental period were increased linearly in response to elevated levels of dietary phytase supplementation (p<0.01). There was no significant difference in average daily feed intake in the whole experimental period. In phase 1, there was a linear increase in apparent total tract digestibility of crude protein (CP), gross energy, and calcium as the level of dietary phytase supplementation increases. Phosphorus digestibility tended to be linearly increased (p = 0.056). In phase 2, linear increases were observed (p<0.01) in calcium and phosphorus digestibility. Additionally, CP digestibility was linearly increased (p<0.05). Dry matter digestibility showed a quadratic effect (p<0.05). The digestibility of arginine, leucine, lysine, tryptophan, alanine, and phenylalanine and cysteine showed a linear increase (p<0.01). There was a linear increase (p<0.01) in blood myo-inositol levels in phase 2.

Conclusion: Dietary phytase supplementation at levels greater than 1,000 FTU/kg significantly improved growth performance, nutrient digestibility, and blood myo-inositol concentrations in weanling pigs. However, further studies are necessary to investigate the effects of super dosing and to determine the optimal phytase dosage.

Objective: Since the liver is key to poultry lipid metabolism and fasting models are widely used in studying animal nutrition metabolism, this study used fasting to explore chicken liver lipid metabolism characteristics, providing a basis for poultry lipid metabolism research.

Methods: RNA-seq and metabolomics were combined to analyze 72-hour fasting effects on chicken liver lipid metabolism. Key lipid metabolism-related genes and metabolites were identified, with their mechanisms explored via RNAi and Oil Red O staining.

Results: Metabolomics identified 648 differential metabolites, including 8 (e.g., Arachidonoyl amine) with levels 160-fold higher than controls. Transcriptomics found 849 differentially expressed genes (DEGs), 78 involved in lipid metabolism; Protein-protein interaction analysis revealed hub genes like EHHADH. Transcriptome-metabolome correlation analysis showed 101 DEGs correlated with 99 metabolites, with EHHADH associated with 54 metabolites (the most) and linked to 2-methylcrotonoyl-CoA and 5 pathways via KEGG Markup Language. Fasting upregulated EHHADH, whose overexpression/interference altered mRNA levels of Fabp7, Plin2, ACACA, FASN, PPARα, as well as cholesterol/triglyceride levels. EHHADH overexpression reduced LMH cell lipid deposition, while interference increased it, indicating its role in reducing lipid deposition.

Conclusion: Fasting significantly alters chicken liver lipid metabolism, and EHHADH helps reduce liver lipid deposition.

Objective: Although there is some evidence linking weaning stress to altered gut flora and stunted development, the exact nature of this relationship is still up for debate.

Methods: In this study, we employed Granger causality inference to compare the dynamic changes in gastrointestinal microbiota between stressed and non-stressed goat kids, and we validated our findings through a randomized controlled trial involving rumen microbiota transplantation.

Results: Our findings indicated that the alpha diversity and microbial maturity of the rumen microbiota in stressed kids were significantly lower than those in non-stressed kids during the weaning period (p<0.05). Furthermore, the rumen microbiota at pre-weaning could accurately predict the body weight changes during weaning stress period (R2 = 0.99, root-mean-square error of prediction = 0.19). We found that the majority of high-abundance rumen bacteria (89.22%) were retained by the cultured rumen microbiota, and that transplanting this microbiota successfully changed the rumen microbiota (analysis of similarity of microbiota, p<0.05), improved growth performance (p<0.05) during weaning, and enhanced microbial maturity (p<0.05), but had no effect on the gut microbiota (p>0.05). Additionally, transplantation of the cultured rumen microbiota reduced intestinal permeability and inflammation while increasing antioxidant levels in weaned kids (p<0.05).

Conclusion: These findings provide evidence for the association between rumen microbiota and weaning stress, demonstrating that manipulating rumen microbiota is an effective strategy for alleviating weaning stress in goat kids.

Objective: This study evaluated the rheological properties of pork myofibrillar protein (MP) gels, as well as the physicochemical and textural properties of low-fat model sausages (LFMS) formulated with various levels of chickpea powder (CPP) processed via freezedrying (FCP) or oven-drying (OCP).

Methods: Pork MP gels and LFMS were prepared with varying concentrations (0%-1.5%) of CPP, either as FCP or OCP. Viscosity, cooking yield, gel strength, protein surface hydrophobicity, and sulfhydryl group levels were analyzed, in conjunction with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and low-vacuum scanning electron microscopy (LV-SEM) investigations, to evaluate the rheological properties and protein structural changes in MP gels after CPP addition. Additionally, cooking loss, expressible moisture, texture profile, SDS-PAGE, and LV-SEM analyses were conducted to assess the physicochemical and textural properties of LFMS containing CPP. The data were analyzed using one-way and two-way ANOVA, followed by Duncan's multiple range test (p<0.05) to determine significant differences.

Results: Increases in CPP concentration enhanced MP gel viscosity, cooking yield, and gel strength; 1.5% CPP yielded optimal water retention and structural integrity. CPP reduced protein surface hydrophobicity and sulfhydryl content while increasing disulfide bond formation, indicating improved gel network formation. SDS-PAGE confirmed myosin heavy chain reduction and the formation of higher-molecular-weight polymers. In LFMS, CPP reduced cooking loss and expressible moisture; OCP was more effective at higher levels. Texture analysis showed increased hardness and chewiness, whereas cohesiveness and springiness remained unchanged. Microscopy revealed a denser, more uniform structure in sausages containing 1.5% CPP. These changes were correlated with improved water retention and texture.

Conclusion: The findings in this study suggest that CPP, particularly OCP, is a promising functional ingredient for efforts to improve meat product quality by enhancing water retention, gel strength, and texture. CPP also promotes protein polymerization, contributing to a more stable gel network.

Objective: Chickens and ducks are among the most important poultry species in the livestock industry. However, the availability of SNP chips for these species is limited, and developing separate chips for each species requires considerable cost. To overcome this limitation, we developed the first poultry SNP chip that can be applied to both species simultaneously. The 60K SNP chip was designed to include 30,816 SNPs for chickens and 35,209 SNPs for ducks. The performance of the chip was evaluated using non-pooled datasets (chicken only and duck only) and a pooled dataset in which chicken and duck DNA were mixed to verify that genotyping accuracy was maintained without cross-species interference.

Methods: DNA was extracted from 28 Korean native chickens and 28 Korean native ducks. Genotyping was performed on the Illumina platform with chicken-only, duck-only, and pooled chicken-duck SNP panels. Genotype accuracy and concordance were evaluated with PLINK. Sample and SNP quality were assessed according to the Illumina genotyping protocol. Principal component analysis (PCA) was conducted to assess and compare the chicken-duck pooled dataset with the non-pooled datasets.

Results: The mean genotype concordance of non-pooled (chicken only and duck only) datasets exceeded 99%, while concordance between non-pooled and chicken-duck pooled datasets was higher than 97.8%. All datasets satisfied quality thresholds for call rate, GenCall score, 10% GenCall score, and cluster separation. PCA revealed consistent clustering patterns, with no significant differences observed between non-pooled and pooled datasets.

Conclusion: We successfully developed and validated the first poultry SNP chip incorporating chicken-duck pooled samples. This chip provides reliable genotyping performance for both species and offers a cost-effective solution for large-scale SNP chip development in the livestock industry.

Objective: The study aimed to investigate the effects of varying dietary crude protein levels on laying performance, nitrogen balance, odor emission, and yolk corticosterone in laying hens from 33 to 64 weeks.

Methods: Two hundred and forty laying hens (Hy-Line Brown) were randomly assigned to one of four varying protein diets from 18.5 to 12.5% at 33-45 weeks, from 18.0 to 12.0% at 46-55 weeks, and from 17.0 to 11.0% at 56 to 64 weeks.

Results: Laying performance (i.e., egg weight, egg production, and egg mass, p < 0.05) was linearly declined with decreasing dietary crude protein levels. Eggshell thickness decreased (quadratic effect, p = 0.033) at 44 weeks of age, while increased (linear effect, p < 0.001) at 52 weeks of age as dietary protein levels lowered. Decreasing dietary protein levels linearly increased (p < 0.05) Haugh unit at 52 and 64 weeks. Apparent digestibility of dry matter and crude protein increased at 45 and 55 weeks of age as dietary protein levels decreased. Lowering dietary protein levels increased the concentration of high-density lipoprotein cholesterol (linear effect, p = 0.012) but decreased (linear effect, p = 0.021) uric acid levels in serum samples at 64 weeks of age. Nitrogen excretion linearly declined as dietary protein levels decreased at all ages. Among the odors analyzed, fecal volatile fatty acids increased at 55 weeks of age with decreasing dietary protein levels. Finally, yolk corticosterone was not altered by dietary protein levels during the laying cycle.

Conclusion: It is concluded that decreasing dietary protein levels fortified with limiting amino acids can be applied to mitigate nitrogen excretion without affecting nutrition-mediated stress in laying hens.

Objective: Weaning stress impairs calf health by causing growth retardation and immune dysfunction, underscoring the need for targeted interventions. Maternal bovine appeasing substance (MBAS) has been proposed as a novel therapy for stress in cattle, but its efficacy against weaning stress remains unclear. This study assessed the health impacts of weaning and evaluated MBAS as a potential intervention.

Methods: Health impacts were first evaluated in 60 weaned Holstein calves. Then, another 60 healthy calves of similar age were randomly divided into two groups (n=30/group). Control calves received a single 2.5 mL saline spray one day pre-weaning, while the MBAS group received a single 2.5 mL spray of MBAS (100 mg/mL).

Results: Weaning stress increased diarrhea (56.52% to 78.26%) and respiratory disease incidence (10.17% to 15.88%), elevated exercise steps (32196±1267 vs 38226±1132, p=0.0043), and reduced dry matter intake (2.78±0.03 vs 2.59±0.06 kg/d at D4, p=0.0041) and average daily gain (ADG, 0.89±0.05 vs 0.71±0.04 kg/d, p=0.0230) within 15 days post-weaning. MBAS improved ADG (0.92±0.15 vs 1.25±0.14 kg/d at D7, p=0.0120), lowered respiratory disease (23.07% to 17.42%) and diarrhea incidence (83.70% to 52.70%), and shortened diarrhea duration (4.32±0.47d vs 3.15±0.32d, p=0.0090). It also reduced serum interleukin-1 (49.39±2.40 vs 43.51±1.64 pg/mL, p=0.0350), haptoglobin (58.29±3.3 vs 49.40±3.65 μg/mL, p=0.0050), and cortisol (37.42±1.67 vs 33.05±2.24 nmol/L, p=0.0310), while increasing immunoglobulin G (10.30±1.46 vs 13.50±1.58 μg/mL, p=0.0131) and interferon-γ (6.89±0.47 vs 7.94±0.63 ng/L, p=0.0330) on D5.

Conclusion: MBAS alleviates weaning stress by inhibiting inflammation, enhancing immunity, and reducing anxiety, providing an effective strategy to improve calf health.

Objective: This study sought to delineate the molecular mechanisms through which the deubiquitinase MYSM1 modulates the proliferation and differentiation of bovine skeletal muscle satellite cells (BSMSCs), thereby offering novel theoretical insights into the regulation of muscle growth and development in beef cattle.

Methods: An in vitro BSMSC model was established to investigate the role of MYSM1. Temporal expression patterns of MYSM1 during cell proliferation and differentiation were analyzed using qRT-PCR. MYSM1 knockdown models were generated, and expression of proliferation markers (PAX7, Ki67) and differentiation markers (MYHC, MYOG) was examined by qRT-PCR and Western blotting. Protein-protein interaction predictions (STRING database) identified BRG1 as a potential MYSM1 interactor, and its function was assessed. Downstream signaling pathways were analyzed by detecting phosphorylation changes in AKT/mTOR pathway proteins. In addition, global histone ubiquitination (H2AK119ub1) and methylation (H3K27me3, H3K4me3) were measured following MYSM1 knockdown.

Results: MYSM1 expression was dynamically regulated, exhibiting significant upregulation during differentiation and reaching a peak at days 2-3 (p < 0.05). Silencing of MYSM1 markedly decreased the expression of PAX7, Ki67, MYHC, and MYOG (p < 0.05). Histone modification analyses demonstrated elevated levels of H2AK119ub1 and H3K27me3, accompanied by reduced H3K4me3 (p < 0.05). Mechanistic investigations further revealed that MYSM1 knockdown suppressed BRG1 expression (p < 0.05), and silencing of BRG1 produced comparable reductions in proliferation- and differentiation-related markers. Moreover, interference with either MYSM1 or BRG1 significantly attenuated activation of the AKT/mTOR/NF-κB pathway, as evidenced by decreased phosphorylation of AKT1, mTOR, and p65 (p < 0.05).

Conclusion: s: MYSM1 promotes the proliferation and differentiation of BSMSCs through BRG1-mediated epigenetic regulation and activation of the AKT/mTOR/NF-κB signaling cascade. These findings establish a dual-target framework that not only advances the understanding of muscle development in beef cattle but also offers potential strategies for regenerative therapies.

Objective: Genome-wide association study and haplotype analysis to identified molecular markers and candidate genes associated with these fleece traits in Inner Mongolia cashmere goats.

Methods: Whole-genome resequencing and phenotypic data from 2,299 Inner Mongolia cashmere goats (IMCGs) were used to conduct Genome-wide association studies (GWAS) using multiple models. Significant SNPs were subsequently annotated and analyzed through functional enrichment. Additionally, Haplotypes were constructed for the significant sites, and association analysis was conducted between the haplotypes and phenotypes to identified molecular markers and candidate genes associated with these fleece traits.

Results: Nine key genes were detected to be associated with fleece traits using candidate gene-based association analysis. Including LAMA3, KCTD1, and PTK7 for cashmere yield (CY); FGFR3, LEF1, and TAPT1 for fiber length (FL); PTCH1 for cashmere length (CL); EVC and ELOVL6 for cashmere diameter (CD). Furthermore, Haplotype analysis identified that the A1A1, C1C1, E2E2, F1F1, G1G1, H1H1, and K1K1 haplotype combinations represent superior haplotype combinations for fleece traits. These could serve as important molecular markers to improve the accuracy of early selection and the economic efficiency of breeding programs.

Conclusion: In conclusion, this study revealed the genetic architecture of fleece traits through GWAS, gene annotation, and haplotype analysis, offering valuable theoretical and marker resources for molecular breeding in IMCGs.