Animal Bioscience最新文献

Objective: Sodium butyrate (SB) is a potentially useful feed additive; however, its effects on lipid metabolism in adipose and liver tissues of lambs are still not fully explored. This study systematically examined the effects and underlying mechanisms of dietary SB supplementation on lipid metabolism in lamb adipose and liver tissues from an adipose-blood-liver perspective.

Methods: Twelve 3-month-old male lambs (22.37±2.05 kg) were randomly divided into a control group and an SB group. We measured the adipose tissue cellular morphology and lipid metabolism-related indices in both adipose and liver tissues.

Results: The results indicated that SB significantly reduces abdominal and perirenal adipose tissue mass, as well as the average area and diameter of adipocytes (p<0.05). Dietary supplementation with SB activated adenosine 5'-monophosphate-activated protein kinase α1 (AMPKα1) in lamb adipose tissue, resulting in upregulated mRNA expression of hormone-sensitive triglyceride lipase (HSL) and downregulated mRNA expression of sterol regulatory element-binding protein 1 and fatty acid synthase (p<0.05). Simultaneously, adiponectin secretion and receptor expression in adipose tissue, as well as serum adiponectin levels, were significantly elevated (p<0.05). Moreover, dietary supplementation with SB increased the levels of tricarboxylic acid cycle metabolites in lamb liver, including oxaloacetate, citrate, cis-aconitate, and succinate (p<0.05), while simultaneously activating the liver AMPKα1 signaling pathway. These changes led to upregulated HSL, platelet glycoprotein 4, and long-chain acyl-CoA synthetase mRNA expression (p<0.05), thereby enhancing liver fatty acid metabolism.

Conclusion: In summary, dietary supplementation with SB alters adiponectin levels in lambs, activates the AMPK signaling pathway, promotes adipose tissue lipolysis, and regulates liver lipid metabolism. The findings provide valuable insights into the use of SB for managing lamb body fat reserves and offer a robust basis for further research in animal bioscience.

Objective: Poultry producers use alternative housing arrangements, such as free-range systems, to allow birds to express their natural behaviors and to enhance consumer confidence in poultry products. Free-range systems provide hens with access to open spaces and better airflow, offering opportunities for thermoregulation through natural behaviors such as seeking shade or dust bathing. Compared to confined cage conditions, this can help reduce the negative effects of heat stress. In this study, we examined the productivity of laying hens segregated for the naked neck gene (Na) and raised in two distinct housing systems.

Methods: A total of 540 laying hens, 24 weeks of age, were randomly assigned to a 2×3 factorial design consisting of three genotypes (NaNa, Nana, and nana) and two housing systems (wire cages and free-range pens). Productive performance, egg quality characteristics, immune response, and blood parameters were evaluated over a threemonth period during the hot summer season.

Results: The results showed that introducing the Na gene into chickens raised under hot climate conditions improved egg production, cell-mediated immunity, and eggshell strength. A significant reduction in blood cholesterol levels and the cumulative percentage of broken eggs was observed in naked neck genotypes (NaNa and Nana) compared to the normally feathered genotype (nana). Hens kept in cages produced significantly heavier eggs compared to those in the free-range system. Laying hens kept in a free-range system exhibited a higher relative yolk weight and an increased shell percentage. Additionally, a significant decrease in plasma cholesterol levels was found in layers raised in free-range systems compared to those in wire cages. Eggs produced by hens reared in free-range systems also had a darker yellow yolk color compared to those from caged hens.

Conclusion: Introducing the Na gene into laying hens raised in free-range housing could be beneficial for improving egg production, immunity, and egg quality under high ambient temperatures.

Objective: Establishing chicken primordial germ cells (PGCs) in vitro is critical for producing genetically modified (GM) chickens. Efficient and reliable isolation and cultivation of PGCs remain significant challenges in advancing avian genetic modifications. To address these challenges, we employed a streamlined and practical approach for the efficient isolation and stable cultivation of chicken gonadal PGCs.

Methods: Chicken gonadal PGCs were isolated from embryonic gonads, surgically removed and dissociated using trypsin. The PGCs were isolated by exploiting differential adhesion properties, allowing fibroblasts to attach while PGCs remained suspended. Cultivation was performed with mitotically inactivated SIM mouse embryo-derived thioguanineresistant (STO) feeder cells under optimized culture conditions.

Results: PGCs proliferated robustly, reaching over 105 cells within one month, which is comparable to previously reported methods. Characterization assays confirmed the expression of PGC-specific markers, including SSEA-1 and DAZL, along with pluripotencyrelated genes such as OCT4 and NANOG. Additionally, injected PGCs successfully migrated to recipient embryonic gonads, where their presence was confirmed by fluorescence analysis and PCR.

Conclusion: This study highlights the effectiveness of the STO feeder-based culture system in avian germ cell research, contributing to progress in the production of germline chimeric and GM chickens.

Objective: This study aimed to determine the effects of cecropin on the growth performance, antioxidant capacity, immune function, rumen fermentation parameters, and rumen microbiota of goats.

Methods: Twelve male Yudong black goats were randomly divided into two groups, with 6 replicates per group. The control group (CON) was fed a basic diet, while the antimicrobial peptide group (AMP) received a diet supplemented with 500 mg/kg cecropin. The experimental period lasted for 60 days.

Results: Compared with the CON group, the AMP group showed significantly improved FW (35.46 vs. 37.33 kg, p<0.05), average daily gain (205.19 vs. 234.78 g/d, p<0.05), and reduced feed-to-gain ratio (6.45 vs. 5.66, p<0.05). The AMP group presented significantly higher SOD, GSH-Px, and CAT activities and total antioxidant capacitylevels in the serum, while the MDA content was significantly lower (p<0.05). Furthermore, compared with the CON group, the les of IgG, IgA, and IL-10 in the AMP group were significanveltly increased, while the levels of IL-2, IL-6, IL-1β, and TNF-α were significantly decreased (p<0.05). In the rumen fluid, the AMP group presented significantly greater propionate and total volatile fatty acid levels, with a significantly lower acetate/propionate ratio (p<0.05). Microbial analysis revealed differences in rumen microbiota diversity and composition between the two groups. At the phylum level, the AMP group presented significantly greater abundances of Bacteroidota, Fibrobacterota, Desulfobacterota, and Elusimicrobiota, whereas the Firmicutes abundance was significantly lower than that in the CON group (p<0.05). At the genus level, the AMP group presented significantly greater abundances of Prevotella, Rikenellaceae_RC9_gut_group, F082, Fibrobacter, Prevotellaceae_ UCG-003, Bacteroidales_RF16_group, Christensenellaceae_R-7_group, and UCG-010, whereas the abundances of Prevotellaceae_UCG-001 and Butyrivibrio were significantly lower (p<0.05).

Conclusion: Overall, these results suggest that adding 500 mg/kg cecropin to the diet promotes goat growth performance by improving serum antioxidant capacity and immune function, optimizing rumen fermentation parameters, and modulating rumen microbiota.

Objective: Bacillus coagulans is a spore-forming probiotic known for its resilience and metabolic activity, both of which are desirable in promoting gut health and oxidative balance. Nonetheless, the beneficial effects of B. coagulans-fermented bedding (BFB) on raising native Chinese chicken breed farming remain largely unknown. This study was conducted to evaluate BFB supplementation on growth performance, meat quality and gut health in Jiuyuan Black chicken.

Methods: A total of 120 male chicks were allocated to the control (CON, using traditional litter) and BFB groups with four replicates per group containing fifteen birds. The chickens were monitored for 70 days; growth performance was evaluated on days 35 and 70, while meat quality, intestinal integrity, antioxidant capacity, and animal welfare were evaluated on day 70.

Results: The results showed that, after 70 days, the chickens in the BFB group exhibited significantly higher average daily gain, lower feed conversion ratio, and increased semi-eviscerated yield and intramuscular fat content compared to the CON group (P < 0.05). Breast muscle from the BFB group showed enhanced flavor and juiciness than the CON group (P < 0.05). Furthermore, the histological analysis of the jejunum demonstrated increased villus height-to-crypt depth ratio, alongside upregulated expression of tight junction proteins (Claudin-1 and ZO-1) (P < 0.05). Additionally, total antioxidant capacity, catalase, and superoxide dismutase activities were increased, with reduced malondialdehyde levels in the serum and jejunal tissue (P < 0.05). Furthermore, BFB improved Jiuyuan Black chickens feather coverage (P < 0.05).

Conclusion: This study indicated that BFB treatment was a good source of reducing oxidative stress in broilers by improving gut health, antioxidant capacity and meat quality which may provide an essential proof for the practical application to enhance growth performance without causing welfare issues in poultry.

Objective: This study aimed to investigate the intrinsic relationships between meat quality, protein properties, and enzyme activities of pork longissimus dorsi treated with L-lysine (Lys) during postmortem aging.

Methods: The pork samples were collected from 18 twelve-month-old crossbred pigs (120 kg, Duroc×Long White Large×White, longissimus dorsi muscle) in three batches of six samples each. The meat was then immediately placed in a thermal container and transported to the laboratory within 1 hour for subsequent processing at 4°C. After removing fat and connective tissue, the pork was cut into 20 g±1 g meat blocks. Then, the samples were vacuum sealed and left in a freezer (4°C) for 0, 1 and 3 days.

Results: The results showed that Lys addition (0.10%, 0.15%, and 0.20%) improved pork quality (water-holding capacity and tenderness). On the third day of aging, the shear force values reached their lowest levels (p<0.05), measuring 38.21 N, 34.04 N, and 30.94 N for the respective treatment groups. In addition, the postmortem addition of Lys significantly increased the myofibrillar fragmentation index and actomyosin solubility during pork aging (p<0.05), with maximum values of 105.07% and 90.35%, respectively. Meanwhile, microscopic structure and electrophoresis results indicated that Lys treatment disrupted the muscle fiber structure, promoted the degradation of myofibrillar proteins (MPs) and dissociation of actomyosin. Furthermore, with increasing Lys addition, calpain-1 activity, caspase-3 activity, and Ca2+-ATPase activity in the muscle significantly increased (p<0.05), reaching maximum values of 17.46 ng/mL, 55.68 μg/mL, and 2.79 μmol (Pi)/min·mg protein, respectively. The activation of these enzymes promoted the dissociation and hydrolysis of key structural proteins.

Conclusion: Lys improved pork quality by increasing calpain-1, caspase-3, and Ca2+-ATPase activity during the postmortem aging, thereby promoting the degradation of MPs and the dissociation of the actomyosin.

Objective: The growth and development of secondary hair follicles primarily determine the economic value of cashmere traits, significantly influencing the quality of cashmere fineness. Previous studies have concentrated on the periodic growth regulation of hair follicles in Inner Mongolia cashmere goats (IMCGs), identifying numerous candidate genes that influence cashmere traits. Research on the factors and regulatory mechanisms affecting cashmere fineness in different body parts is currently limited.

Methods: The differences of cashmere fineness traits among different body parts or ages were determined by multiple comparison analysis testing in analysis of variance. RNA-seq and Gene Ontology (GO) & Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were used to assess the differentially expressed genes (DEGs) across different body parts of IMCGs. The candidate genes were validated using quantitative realtime polymerase chain reaction techniques.

Results: Ages and different body parts had significant effects on cashmere diameter of IMCGs (p<0.05). Cashmere diameter was coarsest in the abdomen, but finest in the neck and back. A total of 2,178 DEGs were specifically screened among four body parts based on cashmere diameter. GO and KEGG analyses showed that these DEGs were mainly enriched in signaling pathways related to hair growth, such as MAPK signaling pathway and extracellular matrix-receptor interaction. The expression of MATN2 and CA12 were consistent with the phenotype of cashmere fineness in different body parts.

Conclusion: The differences of cashmere fineness among different body parts of IMCGs were investigated through transcriptome and phenotype analysis, which provide a basis for understanding molecular regulation of cashmere growth in cashmere goats. ATN2 and CA12 have been validated as regulatory genes influencing the heterogeneity of cashmere fineness in various parts of IMCGs.

Objective: This study aimed to characterize the genomic distribution and amino acid homology of porcine endogenous retrovirus (PERV) subtypes in three pig breeds, Jeju native pigs (JNPs), Duroc, and Landrace.

Methods: Genomic DNA was extracted from hair and ear tissue samples of JNPs, Duroc, and Landrace breeds using DirEx Fast Hair Kit and Exgene Tissue SV Plus kit (GeneAll). Whole-genome resequencing (WGR) was performed by using the Illumina NovaSeq 6000 platform. Sequencing libraries were prepared using the TruSeq Nano DNA Kit and qualitychecked using QUAST and BUSCO, and aligned to the Sus scrofa 11.1 reference genome with Bowtie2. Polymerase chain reaction (PCR) and quantitative real-time PCR were conducted with subtype-specific primers targeting gag, pol, and env regions. Amplicons were verified via agarose gel electrophoresis, purified, and subjected to Sanger sequencing.

Results: WGR revealed breed-specific differences in PERV insertion, with JNPs exhibiting a higher frequency compared with the commercial breeds. PERV-B was the most abundant subtype, followed by PERV-CA and PERV-A, whereas PERV-C was absent in all the breeds. Chromosomal mapping highlighted variations in the localization of PERV, with notable absence on chromosomes 10 and 18. Homology analysis of amino acid sequences of PERV-A, PERV-B, and PERV-CA revealed breed-specific variations in the gag, pol, and env regions, indicating potential differences in viral replication and infectivity. The presence of all PERV subtypes were confirmed using polymerase chain reaction, with PERV-C detected in some Western breeds and all the JNPs analyzed. Sequencing of the PERV-C env region revealed single nucleotide polymorphisms, indicating genetic divergence among pig breeds.

Conclusion: The study findings highlight the need for breed-specific strategies in PERV inactivation for xenotransplantation applications. The distinct chromosomal distribution patterns and functionally significant PERV insertions identified in this study provide a foundation for future research into host-virus interactions and retroviral evolution.

The objective of this review was to describe the enzymatic properties of multiple inositol polyphosphate phosphatase (MINPP1/MIPP) as an unusual member of histidine acid phosphatase, distinct from conventional microbial phytases and their additional physiological functions besides degrading phytate. Considering parameters such as pH activity profile, substrate specificity, catalytic efficiency, and stability, MINPP1 is of merit as a novel phytase source for developing an ideal feed additive supported by functional metagenomics fused with recombinant DNA technology and classical protein engineering. In addition, MINPP1 appears to be involved in some biological activities such as cell survival, stress, lipopolysaccharide and inorganic polyphosphate-induced inflammatory response, milk fatty acid composition-related metabolism and bone-related growth and pathophysiology, which can be important for the production performance of farm animals. Future directions need profound studies revealing the direct effects of MINPP1 on these physiological events.

Objective: Oocyte quality is critical for the stable transmission of genetic information and affects early embryonic development. But the precise mechanisms governing oocyte meiotic progression remains largely unclear. Transcription regulation through chromatin compaction and decompaction is regulated through various chromatin-remodeling complexes such as nucleosome remodeling and histone deacetylation (NuRD) complex. GATAD2B is known to be a component of the NuRD complex but whether GATAD2B regulates chromatin modification in mouse oocyte meiosis remains unclear. We hope to explore the role of GATAD2B in mouse oocyte meiosis.

Methods: In this study, we initially utilized western blot and immunofluorescence to delineate the expression and subcellular localization of GATAD2B during oocyte meiotic maturation. To further elucidate the role of GATAD2B in regulating oocyte meiotic division, we employed the method of microinjection of Gatad2b-specific siRNA to knock down the protein expression of GATAD2B. Subsequently, dynamic changes in oocyte meiotic division were captured in real-time using live-cell imaging with Geri. Additionally, spindle staining, DNA staining, spread analysis, and reanalysis of RNA-seq data were performed to investigate the mechanisms through which GATAD2B regulates oocyte meiotic division.

Results: GATAD2B was stably expressed during oocyte meiosis and was significantly increased during the metaphase II (MII) stage. To further explore the effect of GATAD2B on oocyte meiotic maturation, we observed increased abnormal spindle, severe chromosome misalignment and metaphase I (MI) block in GATAD2B knocked-down (GATAD2B-KD) oocytes. Interestingly, the distribution of microtubule organizing center was abnormal and aneuploidy was significantly increased in GATAD2B-KD oocytes. In addition, some deacetylation-related genes were significantly downregulated and acetylated proteins accumulated abnormally in GATAD2B-KD oocytes.

Conclusion: These findings implicate GATAD2B as a novel regulator of histone deacetylation during oocyte maturation and provide evidence that such deacetylation is required for proper spindle assembly.