Animal Bioscience最新文献

Objective: This study explored the molecular mechanism of the hypothalamus-pituitary-gonadal (HPG) axis on the regulation of brooding behavior and laying performance of Wanxi white geese (WWG). The transcriptome of the hypothalamus, pituitary, and ovarian tissues of laying and brooding WWG was sequenced to identify genes and long noncoding RNAs (lncRNAs) that may be important in regulating the egg-laying performance and broodiness behavior of WWG.

Methods: This study sequenced the lncRNA on the hypothalamus, pituitary, and ovarian tissues of WWG white geese during laying and broodiness periods to determine the differentially expressed lncRNA (DElncRNA) in the hypothalamus-pituitary-ovary axis. lncRNA- microRNA (miRNA)-messenger RNA (mRNA) (ceRNA) regulatory network was constructed using selected differentially expressed genes (DEGs), differentially expressed microRNAs (DEMs), and DElncRNAs. Differentially expressed DEGs, DEMs, and DElncRNAs were further confirmed via real-time quantitative polymerase chain reaction. The dual luciferase reporter gene assay confirmed a targeting relationship between the MSTRG.1166. 1/miR-450-x/SOX8 axis.

Results: A total of 184 (brooding period hypothalamus vs laying period hypothalamus), 180 (brooding period pituitary vs laying period pituitary), and 880 (brooding period ovary vs laying period ovary) DElncRNAs were screened. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes functional enrichment analysis showed that the DElncRNAs significantly enriched Steroid hormone biosynthesis, Neuroactive ligand-receptor interaction, Calcium signaling, and other pathways. The ceRNA regulatory network of laying performance and nesting behavior was constructed through the database. MSTRG.1166.1-miR-450-x-SOX8, MSTRG. 7163.5-miR-182-x-CSMD1, XR_007167835.1- miR-277-z-RAB3B, MSTRG. 7163.5-miR-151-y-PAQR9, MSTRG.4615.2-miR-96-x-DAPK1, XR_007164924.1-miR-144-y-TFPI, XR_007161186.1-miR-205-x-THRB, MSTRG.10196.1/XR_001206277.2-miR-339-x-TRAF4, and MSTRG.9442.1-miR-9-y-FBN3 may play an important role in the ovarian development of WWG. The dual luciferase reporter gene assay confirmed a targeting relationship between the MSTRG.1166.1/miR-450-x/SOX8 axis. The results of this study systematically expounded on how the HPG axis involves lncRNA, miRNA, and mRNA to post-transcriptionally regulate the broodiness behavior and laying performance of WWG.

Conclusion: The results will improve knowledge of the complex interaction between lncRNA and genes controlling laying performance and broodiness behavior.

Objective: Vanaraja is a highly successful backyard chicken variety developed by crossing males of Vanaraja male line (PD-1) with females of Vanaraja female line (PD-2). Vanaraja was improved over the generations through selection in parent lines. This study was designed to estimate the genetic parameters and trend for major traits in PD-2 line in order to determine the future breeding strategy in the population.

Methods: Seven generations data of PD-2 population was utilized to precisely examine the existing additive genetic variability for the major growth and production traits. Egg mass at 52 weeks of age (EM52) is the primary selection trait. The best-fitted model for each trait was utilized out of the six models to obtain the genetic parameters. Subsequently, estimated breeding values were used to plot genetic trend for the major production traits.

Results: Models with maternal genetic and permanent environmental effects were identified as the best-fitted for most of the body weight traits. Model 1 with direct additive effect only as random effect was adjudged as the best for the primary selection trait EM52. EM52, was low heritable with the estimates as 0.13±0.03. The average estimated breeding value of EM52 increased linearly and significantly as a direct response to selection in PD-2 line and was 0.47 kg after seven generations of selection.

Conclusion: Based on the findings, PD-2 population still has sufficient genetic variability for the selection trait and other performance traits. The present breeding program can continue in order to produce genetic improvement in the Vanaraja chicken.

Objective: Phosphates are traditionally employed to improve emulsification and texture in meat products. In response to growing consumer demand for healthier, non-chemical alternatives, this study explored the potential of a non-thermal processing technology-high-voltage electrostatic field (HVEF)-to improve emulsification properties while preserving protein structures. Specifically, the objective was to evaluate the effects of HVEF treatment on the quality of phosphate-free emulsified pork batter.

Methods: Fresh ham was cut and randomly allocated into four groups, including conventional refrigerator with 0.15% phosphate, phosphate (1) and phosphate-free without HVEF (0 kV/m) (2), and HVEF group, phosphate-free with low and high voltage -90 kV/m (3) and -150 kV/m (4) for 24 hours. Making the pork batter and analyzing the emulsifying activity index, emulsifying stability index, total expressible fluid and scanning electron microscope (SEM).

Results: The results showed that the -150 kV/m HVEF group exhibited a significantly higher emulsifying activity index than Phosphate and 0 kV/m group (p<0.05), enhancing emulsification. After processing, the -90 kV/m HVEF group retained more moisture than phosphate and 0 kV/m groups (p<0.05). For total exudate loss (TEF) and fat loss, -150 kV/m group exhibited the highest TEF and fat loss, whereas the -90 kV/m group had lower TEF than 0 kV/m group, suggesting -90 kV/m HVEF improves emulsion stability. SEM revealed denser and smoother structures in phosphate and -90 kV/m groups.

Conclusion: -90 kV/m HVEF enhances water retention and structural stability in emulsified pork batter, offering a viable phosphate alternative for high-quality meat products.

Nanostructured lipid carriers (NLCs) are promising in target and efficient delivery of bioactive compounds with high loading capacity of bioactives, better physical stability, better encapsulation efficiency, solubility and bioavailability in comparison to the conventional delivery systems for lipophilic and hydrophobic bioactives such as essential oils and phytochemicals as well as functional feed ingredients. There are different types of NLCs combining solid lipid and liquid lipid in a single nanoparticulate matrix that have advantages over other drug delivery systems. The NLCs can be synthesized in form of imperfect, amorphous, oil-enriched, surface modified or functionalized, hybrid or composite and multiple-compartment or double-shell NLCs. Moreover, the synthesized NLCs safety, efficacy, toxicity, encapsulation efficiency, drug loading and releasing capacity, reproducibility in large scale were evaluated. The application of NLCs for the effective and target delivery of bioactive compounds are widely reported in biomedical and therapeutic studies. However, utilization of NLCs for the effective delivery of bioactive compounds is very limited in swine and poultry health. There are some recent studies reported that NLCs with can enhance growth, antioxidant capacity, immunity, gut health and microbiome as well as disease resistance in swine and poultry. This review focuses on recent developments and future prospects of utilizing NLCs in swine and poultry health management. Regardless of the potential beneficial effects of NLCs in nanodelivery of bioactive compounds, further research on long-term field oriented studies in livestock and poultry farms and economic analysis of manufactured NLCs should be carried out.

Amino acid (AA) requirements reported in previous literature, such as those of the National Research Council (NRC) published in 2012 based on pre-2010 data, do may not adequately reflect the improved genetic potential of pigs and thus require updating. Accordingly, this review aimed to provide recent updates on the AA requirements of pigs based on the standardized ileal digestible (SID) lysine (Lys) to net energy (NE) ratio (SID Lys:NE) and the ideal ratios of SID methionine (Met), threonine (Thr), tryptophan (Trp), valine (Val), and isoleucine (Ile) to SID Lys (SID AA:Lys), derived from meta-analyses for average daily gain (ADG) and gain-to-feed ratio. The optimal SID Lys:NE for ADG in this review are consistently greater than the ratios reported by the NRC across different phases, indicating that the improved genetic potential for lean growth requires greater optimal SID Lys:NE. The optimal SID Met:Lys, SID Trp:Lys, and SID Ile:Lys for ADG remain constant with increasing body weight (BW) of pigs, but the ratios are also greater than those reported by the NRC. However, the optimal SID Thr:Lys for ADG increases as BW of pigs increases, likely due to the increasing proportion of maintenance requirement relative to the total Thr requirement. The optimal SID Val:Lys for ADG is greater in the nursery phase than in the grower phases, suggesting that weaning-associated intestinal and immune challenges would increase requirement for Val. Both optimal SID Thr:Lys and SID Val:Lys are greater than the ratios reported by the NRC. In conclusion, these results suggest that the optimal SID Lys:NE and SID AA:Lys in pig diets are greater than the ratios reported by the NRC, and different ratios of SID Thr:Lys and SID Val:Lys should be applied for pigs with different BW.

Objective: The objective of this study is to investigate the nutritional metabolism and growth development of broiler chickens under different methionine (Met):cysteine (Cys) ratios, with a focus on proteomic alterations in the hypothalamus and ileum to elucidate potential regulatory mechanisms.

Methods: A total of 216 one-day-old Arbor Acres broiler chicks were randomized into three groups: low (LMCR, 0.34%:0.56%), medium (MMCR, 0.45%:0.45%), and high (HMCR, 0.53%:0.37%) Met:Cys ratios, with total sulfur amino acids fixed at 0.9%. Each group comprised 6 replicates of 12 chicks, and the experiment spanned 21 days.

Results: Results demonstrated that HMCR significantly improved average daily gain (ADG, p< 0.05), reduced feed conversion ratio (F:G, p<0.05), and enhanced protein/lipid utilization efficiency. Mechanistically, HMCR promoted hypothalamic neurodevelopment, downregulated key components of the protein kinase A (PKA) signaling pathway (P< 0.05) and leptin expression (p< 0.001), while upregulating growth hormone and gastrointestinal hormone secretion. Through the hypothalamic-hormonal-ileal axis, HMCR modulated ileal cell physiology by upregulating inositol 1,4,5-trisphosphate receptors (IP3R, P< 0.05) and phosphoinositide 3-kinase (PI3K,p< 0.05), thereby enhancing ileal villus morphology and nutrient absorption capacity. The improved ileal structure further augmented energy utilization efficiency (p< 0.05).

Conclusion: In conclusion, a dietary Met:Cys ratio of 0.53%:0.37% optimizes broiler growth performance by coordinately regulating metabolic pathways in the hypothalamus and ileum, as well as modulating brain-gut peptide signaling. These findings provide a scientific foundation for formulating sulfur amino acid-optimized diets to enhance poultry productivity and feed efficiency.

Objective: The present study aimed to evaluate the effects of compound probiotics on growth performance, diarrhea incidence, fecal pathogenic microorganisms, and serum parameters in newborn calves.

Methods: A total of 48 healthy newborn calves with similar body weights (mean ± SD: 37.0 ± 2.0 kg) were randomly assigned to three groups (n = 16 per group). Control group (CON), yeast group (CP1), Bacillus licheniformis + yeast group (CP2). The feeding trial lasted for 60 days. Growth performance, diarrhea incidence, fecal scores, and serum parameters were assessed on days 1, 30, and 60 of the trial, while fecal samples collected on days 15 and 30 were analyzed for pathogenic microorganism positivity.

Results: Compared with CON group, calves in the CP2 group had higher body weight (BW; day 30; p<0.05), average daily gain (ADG; days 1-30; p<0.05), and feed efficiency (FE; days 1-30; p<0.05). Compared with CON group, the incidence of diarrhea and fecal scores (days 1-60) were lower in both CP1 and CP2 groups (p<0.05). Fecal samples from these groups also exhibited reduced positive rates of pathogenic microorganisms (rotavirus, coronavirus, cryptosporidium). Notably, compared with CON group, serum antioxidant and immune markers, total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and immunoglobulin A (IgA) levels were elevated (p<0.05), whereas malondialdehyde (MDA) and tumor necrosis factor-alpha (TNF-α) levels were decreased (p<0.05), and serum diamine oxidase (DAO) levels were also reduced in the CP1 and CP2 groups (p<0.05). Furthermore, compared with the CON group, calves in the CP2 group exhibited lower serum cortisol (Cor) and higher growth hormone (GH) levels (p<0.05). No interactions between treatment and period were observed.

Conclusion: The combined use of Bacillus licheniformis and yeast exerts synergistic effects by promoting growth and development in newborn calves, reducing diarrhea incidence, enhancing antioxidant and immune functions, and improving overall health.

Objective: Salmonella Thompson is a major cause of large-scale foodborne disease outbreaks worldwide; however, research on S. Thompson remains limited. This study investigates the development of a predictive model for the growth of S. Thompson in unpasteurized liquid egg products, such as liquid egg white, liquid egg yolk, and liquid whole egg, to understand the associated health risks.

Methods: Unpasteurized liquid egg products, confirmed to be free of Salmonella spp., were inoculated with S. Thompson and incubated at various temperatures. Growth kinetic parameters were estimated using both primary and secondary predictive models, including the Baranyi and Roberts model and second-order polynomial models. The effects of environmental factors on S. Thompson growth were analyzed to establish a comprehensive risk assessment framework.

Results: The growth curves of S. Thompson exhibited a typical bacterial sigmoidal pattern characteristic of bacterial proliferation, with the Baranyi model providing the best fit for describing the growth kinetics. The secondary model accurately predicted the effect of temperature on growth rate, demonstrating that S. Thompson proliferates rapidly under specific environmental conditions. Model validation indicated high accuracy, confirming the reliability of the developed model for risk assessment applications.

Conclusion: The established predictive model enables quantitative assessment of the growth behavior of S. Thompson in unpasteurized liquid egg products. This model can be used in risk assessment and food safety management strategies to mitigate the risk of foodborne pathogen contamination in the food industry.

Objective: This study aimed to investigate the effects of protocatechuic acid (PCA) on Sertoli cells (SCs) in Tibetan sheep, focusing on its impact on cell proliferation, lactate synthesis, and the underlying molecular mechanisms.

Methods: Primary SCs were isolated from the testes of Tibetan sheep and cultured. The effects of PCA on SCs function were evaluated through in vitro experiments, and its molecular mechanisms were further explored. Meanwhile, both in vivo and in vitro mouse models were employed to validate the regulatory mechanisms of PCA on male reproductive function and SCs.

Results: PCA significantly upregulated the expression of proliferation and lactate synthesis-related genes in Tibetan sheep SCs, and increased the intracellular pyruvate and lactate levels. Mechanistically, PCA activated the AMP-activated protein kinase (AMPK) pathway and inhibited the mechanistic target of rapamycin (mTOR) pathway, thereby inducing autophagy in SCs. The use of autophagy inhibitors and AMPK inhibitors effectively blocked PCA-induced promotion of SCs proliferation and lactate synthesis. In mouse model studies, PCA improved sperm count, pregnancy rate, and litter size, and reduced sperm abnormality rate. It also elevated activin A levels and decreased inhibin B levels in testicular tissues, increased serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone (T) levels, enhanced testicular antioxidant enzyme activities, and reduced malondialdehyde (MDA) content. Furthermore, PCA upregulated the expression of proliferation and lactate synthesis-related proteins in mouse testicular tissues and primary SCs, modulated the AMPK/mTOR pathway, and increased autophagic activity.

Conclusion: PCA promotes the proliferation and lactate synthesis in SCs of Tibetan sheep through AMPK/mTOR-mediated autophagy.

Objective: The rumen microbiota plays a pivotal role in fermenting plant biomass, which is essential for nutrient conversion. Although extensive research has examined the intestinal microbiome of Tibetan livestock, the rumen microbiota of semi-fine wool sheep (SF-sheep) remains poorly characterized. This study aimed to profile age-related changes in the rumen microbiota and fermentation parameters of SF-sheep to uncover potential microbial-mediated adaptations to different growth stages.

Methods: Full-grazing male SF-sheep were randomly assigned into three age groups: two-month-old lambs, yearling sub-adults, and approximately 50-month-old adults. 16S rRNA gene sequencing and high-performance liquid chromatography were used to analyze the rumen microbiota composition and short-chain volatile fatty acids (SCVFAs).

Results: Age-dependent differences were observed in ruminal NH₃-N concentrations, with sub-adult sheep exhibiting higher levels than young and adult individuals, whereas SCVFAs concentrations remained relatively stable. With age, the rumen microbial community structure tended to become more homogeneous, whereas microbial diversity and complexity showed a marked increase during adulthood. At the phylum level, Saccharibacteria and Succiniclasticum were enriched in sub-adults, whereas Euryarchaeota and Prevotellace_UCG_001 were more abundant in adults; no microbial biomarkers were detected in young sheep. Correlation analyses indicated that age and NH₃-N concentrations were the primary factors shaping the rumen microbiota. SCVFAs, including acetate, butyrate, and propionate, were positively associated with fibrolytic and polysaccharide-degrading bacteria such as Prevotella_1, Treponema_2, and Selenomonas_1. The rumen microbial communities were classified into two enterotypes. Enterotype 1, predominantly observed in young SF-sheep, showed higher abundances of KEGG Orthologs (e.g., K00656, K00239, K01966) associated with acetate, propionate, and butyrate synthesis.

Conclusion: The rumen microbial ecosystem of SF-sheep undergoes pronounced age-dependent restructuring in microbial composition and diversity, accompanied by nitrogen metabolism. These changes reflect dynamic microbial adaptation to the host's physiological state and potential developmental shifts in nutrient requirements, offering valuable insights for age-specific nutritional management strategies.