Animal Bioscience最新文献

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.

Objective: Navel orange residue (NOR) is considered to improve the silage quality of whole-plant mulberry (WPM) because of its high water-soluble carbohydrate (WSC) content. In order to investigate the mechanism underlying NOR regulated WPM silage quality, the chemical composition, fermentation quality, bacterial community and in vitro digestibility of WPM and NOR mixed silages were analysed.

Methods: WPM and NOR were mixed at ratios of 10:0 (MCK), 7:3 (M7O3), 5:5 (M5O5), and 3:7 (M3O7) on a dry matter (DM) basis. Samples were collected after 15, 30 and 45 days of ensiling to study their chemical composition, fermentation quality, bacterial community and in vitro digestibility. The optimal treatment was identified through membership function analysis.

Results: In comparison with MCK, incorporating 30-70% NOR ensiled for 15-45 days significantly increased DM, WSC, lactic acid, and acetic acid (AA) contents (p<0.05). At the same time, it resulted in a significant decrease in the levels of crude protein, neutral detergent fiber, acid detergent fiber, pH, and NH3-N (p<0.05). The NOR addition encouraged the beneficial heterofermentative species Lactobacillus pontis, Lactobacillus panis, and Lactobacillus buchneri, whilst preventing unfavourable microorganisms (p<0.05). In addition, in vitro rumen fermentation analysis demonstrated that adding 30-70% NOR and ensiling for 15-30 days markedly increased in vitro dry matter digestibility, gas production, total volatile fatty acids, AA, and propionic acid (PA) (p<0.05), along with a significant decrease in the AA/PA ratio (p<0.05). M3O7 ensiled for 15 days and M5O5 ensiled for 30 days achieved high membership function values of 0.839 and 0.732, respectively.

Conclusion: Co-ensiling WPM with 30-70% NOR for 15-45 days significantly enhanced fermentation quality, improved bacterial diversity, and increased in vitro digestibility. Overall, the optimal strategies for producing high-quality silage are co-ensiling WPM with either 70% NOR for 15 days or 50% NOR for 30 days.

Objective: Heat stress adversely affects feed intake, milk production, and overall reproductive performance. One suggested nutritional strategy to mitigate these adverse effects is the optimization of dietary electrolyte balance (dEB) with bicarbonate supplementation, which regulates acid-base homeostasis and thermoregulatory responses. This study aimed to evaluate the effects of different dEB levels on lactating sow reproductive performance during heat stress.

Methods: A total of 40 lactating sows were assigned to four dietary treatments with varying dEB (mEq/kg) levels (230: sodium chloride 0.47%; 250: sodium chloride 0.34%+sodium bicarbonate 0.14%+potassium bicarbonate 0.05%; 270: sodium chloride 0.25%+sodium bicarbonate 0.26%+potassium bicarbonate 0.09%; 290: sodium bicarbonate 0.52%+potassium bicarbonate 0.13%) to evaluate the effects on reproductive performance, hair cortisol, the acid-base balance, inflammation, gut integrity, behavior, and intestinal microbiota of lactating sows during heat stress.

Results: Increasing dietary dEB levels during heat stress (temperature: 26.0-31.1 °C; temperature to humidity index: 78-84) linearly increased average daily feed intake of sows during lactation and improved piglet weaning weight. Blood pH decreased linearly with rising dEB levels, while hair cortisol content showed a decreasing trend. IL-1β tended to decrease with increasing dEB levels, and IL-10 showed a trend to a quadratic peak at 250 mEq/kg before declining. Behavioral analysis showed a quadratic response in standing behavior, peaking at 250 mEq/kg, while position changes decreased linearly with increasing dEB. Beta diversity analysis revealed differences in unweighted UniFrac Principal Coordinate Analysis between 230 and 290 mEq/kg dEB groups. The abundance of the actinobacteriota phylum tended to decrease linearly, however, the abundance of major phyla including the firmicutes and bacteroidota was unaffected.

Conclusion: In conclusion, increasing dietary dEB from 230 to 270-290 mEq/kg with bicarbonate supplementation improved feed intake and piglets weight at weaning, suggesting that a dEB around 270 mEq/kg is optimal for supporting sow reproductive performance under heat stress.

Objective: Rising poultry feed costs and shortages in Southeast Asia, particularly in Thailand, underscore the need for sustainable alternatives. This study evaluated shrimp meal (SM), a protein-rich byproduct, and yam bean (YB), an underutilized energy-rich root crop, as promising alternative feed ingredients for laying hens.

Methods: An in vitro analysis was conducted to determine the chemical composition and digestibility of diets containing SM and varying levels of YB. An 8-week in vivo trial was conducted using 90 ISA-Brown hens (25-week-old), divided into nine dietary groups: one control and eight treatment groups with 10% or 15% SM combined with 0%, 3%, 6%, and 9% YB. Laying performance, egg quality and composition, and nitrogen (N) retention were assessed.

Results: SM was rich in protein, while YB contained high nitrogen-free extracts and gross energy, supporting their use as alternative protein and energy sources, respectively. The inclusion of SM and YB had no negative effect on in vitro dry matter or protein digestibility. In vivo, combined inclusion of up to 15% SM and 9% YB did not adversely affect laying performance, egg quality, nutrient composition, or N retention compared to the control. Main effect analysis revealed that SM significantly enhanced yolk color, eggshell weight, and eggshell thickness, while reducing egg fat content. Although higher levels of SM were independently associated with reduced hen-day egg production and egg mass, these effects were mitigated when SM was combined with YB, resulting in no significant differences from the control group at the highest inclusion levels (15% SM and 9% YB).

Conclusion: SM and YB are viable, eco-friendly alternatives to conventional poultry feed ingredients. Their combined inclusion, up to 15% SM and 9% YB, is recommended to maintain laying performance and egg quality while promoting sustainable feeding practices through the utilization of processing byproducts and underutilized local crops.

Objective: The Licha Black pig (LC) is a nationally protected Chinese indigenous breed known for its superior meat quality and strong environmental adaptability. However, its population has declined rapidly due to extensive crossbreeding with commercial lines. Understanding the genetic basis of its economically important traits is crucial for conservation and genomic improvement.

Methods: Whole-genome resequencing was performed on 120 LC pigs and combined with genomic data from 285 pigs representing 32 global populations, including wild boars, commercial breeds, and other Chinese indigenous pigs. Population structure was investigated using phylogenetic trees, PCA, ADMIXTURE and TreeMix analysis. Selection signatures were identified through four complementary approaches (FST, θπ ratio, XP-CLR, and Tajima's D). Candidate genes were examined by functional enrichment analysis, protein structure prediction, and cross-referencing with trait association and tissue-specific expression databases. Phenotypic data on body size and teat number were also collected in LC pigs for targeted genotype-phenotype analysis.

Results: Phylogenetic analyses showed clear stratification among global pig populations, with Chinese indigenous breeds broadly separated by the Qinling-Huaihe Line. LC pigs formed a distinct genetic cluster between northern Chinese and European breeds. Selective sweep analyses revealed several candidate genes under positive selection, including SOCS6 and ATP2B4 (skeletal muscle development), RASAL2 (adipogenesis), and DOCK2 (male fertility). Trait-focused analyses identified ZNRF3 as a major locus for body size, with a missense mutation (g.46228935G>A; Gln→Arg) predicted to influence Wnt/β-catenin signaling. Signals of selection in ADGRB3, a gene potentially involved in teat patterning and mammary gland vascularization, were associated with variation in teat number.

Conclusion: Our comprehensive genomic analyses provide new insights into the genetic architecture underlying economically important traits and environmental adaptation in the LC. These findings establish a foundation for genomic-informed selective breeding and offer valuable molecular tools for the genetic improvement and sustainable utilization of this indigenous genetic resource.