Journal of Animal Science and Technology最新文献

The objective of this study was to investigate the effects of electron beam (EB) and X-ray (XR) irradiation on dry pet food during long-term storage. The samples were irradiated with EB and XR at doses of 0, 2.5, 5, 10, and 20 kGy, and their microbial safety and quality/oxidation properties were analyzed over 56 days under storage conditions of 25°C and 70% relative humidity. As a result, total aerobic bacteria and yeasts and molds significantly decreased as the doses of EB and XR increased. When treated with 10 kGy for both irradiations, no bacteria were detected in the dry pet food, and this effect remained during the 56-day storage period. While EB and XR were effective in reducing aflatoxin B1 in solution, they showed limited effect on dry pet food. On the other hand, changes in quality traits such as proximate compositions, pH, water activity, color, and volatile basic nitrogen due to EB and XR were negligible. However, both types of irradiation induced lipid and protein oxidation in dry pet food. Also, a significant increase was observed in oxidation-related volatile compounds such as hydrocarbons, aldehydes, and ketones with EB and XR treatment, which suggested these changes could potentially impact the flavor of the dry pet food. The current findings confirm the efficient microbial reduction of dry pet food by EB and XR and the consequent changes in quality and oxidative properties. Future research should focus on sensory evaluations to understand the implications of these oxidized substances on pet preferences and explore potential methods to mitigate negative effects.

Lactococcus lactis subsp. lactis DOME 6301, isolated from bovine milk, produces an antimicrobial compound that inhibits oral pathogens including Streptococcus mutans, Prevotella intermedia, and Fusobacterium nucleatum. The entire genome of L. lactis DOME 6301 was sequenced and assembled de novo using the PacBio RS II platform. The genome was 2,532,858 bp in length, assembled into three contigs, and had a guanine and cytosine (G + C) ratio of 35%. The annotation results revealed 2,469 protein-coding sequences, 22 rRNA genes, and 78 tRNA genes. Genes involved in the utilization of complex carbohydrates (i.e., cellulose, xylose, pullulan, amylose, maltodextrin, and arabinofuranose) and synthesis of the bacteriocin, nisin Z, were detected. In addition, genes encoding antimicrobial resistance and virulence factors (i.e., hemolysin and enterotoxin) were detected. Whole-genome analysis of strain DOME 6301 contributed to our understanding of the evolution of the taxa and provided the basis for the correct selection of probiotic candidates for downstream applications.

Glucose-regulated protein 78 (GRP78), which belongs to the heat shock protein 70 family, is a chaperone essential for maintaining cellular balance in the endoplasmic reticulum. It acts as a receptor on the cell surface, affecting cell growth and survival. Recent research has emphasized the involvement of GRP78 in protein folding, endoplasmic reticulum stress signaling, and cancer cell proliferation and highlighted its presence on sperm cells, where it contributes to spermatogenesis and sperm capacitation. Despite these findings, the association of GRP78 with sperm motility and motion kinematic parameters remains insufficiently understood. This study assessed the correlation between GRP78 and various sperm motility and kinematic parameters, which are essential for the capacitation process. GRP78 expression was positively correlated with linearity and straightness and negatively correlated with total sperm motility and beat cross frequency. However, GRP78 expression did not exhibit a significant correlation with progressive sperm motility, average path velocity, curvilinear velocity, straight-line velocity, and amplitude of lateral head displacement. These results provide novel insights into the correlation between GRP78 and sperm motility, as well as its potential implications for male fertility.

Respiratory diseases have been recognized as a significant cause of reduced livestock productivity since 1995. Respiratory diseases in the swine industry caused by both biological and non-biological factors are collectively referred to as porcine respiratory disease complex (PRDC). However, there is a lack of eco-friendly anti-inflammatory drugs (AIDs) that can effectively control lung inflammation caused by PRDC. P2Y purinoreceptor 14 (P2Y₁₄) has been identified as a key regulator of macrophage inflammatory responses; however, its regulatory role in porcine lung inflammation remains unclear. In this study, we investigated the role of P2Y₁₄ in inflammation in 3D4/31 porcine macrophages and attempted to develop a novel AID. An extract of the Mexican medicinal plant Aporocactus flagelliformis water extract (AFWE) reduced reactive oxygen species production and pro-inflammatory cytokine expression in phorbol myristate acetate-stimulated 3D4/31-PAMs. It also reduced glucose uptake, glycogen accumulation, and expression of genes related to the P2Y₁₄ cascade. Polarity-based fractionation and liquid chromatography-mass spectrometry identified limonin as an anti-inflammatory compound in AFWE. Limonin reduced P2RY₁₄ and proinflammatory gene expression induced by the P2Y₁₄ ligand UDPG in 3D4/31-PAMs, demonstrating its inhibitory effect on P2Y₁₄-mediated inflammation. These results suggest that P2Y₁₄ is an inflammatory receptor in PAMs and an effective target for AID development. We also propose AFWE and limonin as candidate AIDs for pigs.

In the present study, we developed a general-purpose preservative using natural extracts to reduce the residual toxicity and negative health effects of chemical preservatives. This study was conducted to improve the yield of optimized extracts of Psidium guajava, Ecklonia cava, and Paeonia japonica (Makino) Miyabe & Takeda extracts, which have already proven to exert antibacterial effects and verify their effectiveness in meat products. Ultrasonic extraction, a well-known eco-friendly extraction method, was performed to confirm the extraction yield, content of bioactive compounds in the extract, and antimicrobial activity and thus improve the extraction yield of the ethanol extract. In addition, ultrasound extraction was applied to sausages to confirm quality characteristics, including sensory evaluation. The extraction yield increased by 56.8% (P. guajava), 182.0% (E. cava), and 235.0% (Paeonia japonica) compared to the ethanol obtained through ultrasonic extraction of three types of natural products. Furthermore, a 32.53% increase in the extraction yield for the mixture extract was obtained through ultrasonic extraction. The MIC and MBC results for foodborne pathogens to measure the antimicrobial activity demonstrated that extracts obtained through ultrasonic extraction exhibited increased antimicrobial activity against certain pathogens. Total plate counts, Coliform, and Escherichia coli were not detected in all treatments in the sausage storage experiment (4 weeks). Although no significant difference was noted in the VBN of sausages among all treatments during the storage period (4 weeks), TBARS during storage was significantly lower in the natural extract treatments. Among the sensory characteristic evaluations, the overall acceptance scores were significantly higher for P. guajava, E. cava, and Paeonia japonica (Makino) Miyabe & Takeda extracts than for the grapefruit seed extract. Altogether, the extraction yield of P. guajava, E. cava, and Paeonia japonica (Makino) Miyabe & Takeda extracts was improved by about 32.53%, and almost the same effect was confirmed in the sausage application test.

Selected feed additives (probiotics, prebiotics, synbiotics, postbiotics, phytogenics, feed enzymes, and organic acids) are reviewed for reported biological responses, and some recent developments when incorporated into laying hen diets. Several feed enzymes (phytase, carbohydrase, protease, and multi-enzymes) have been adopted to improve the nutritive quality of feedstuffs by mitigating inherent digestive function inefficiencies, complementing endogenous enzyme activity, and cleaving anti-nutritional factors abundant in vegetable-based poultry diets. Phytase use is targeted at hydrolyzing phytate to liberate phosphorus and possibly other encapsulated nutrients, with widely reported environmental and economic benefits. Proteases often improve the hydrolysis of amino acids and protein complexes to improve dietary protein digestibility and utilization, potentially restoring performance losses and maintaining the egg quality of hens fed low-protein diets whose CP level has been further reduced. The digestibility-enhancing effects of fiber-degrading carbohydrases are associated with the reduction of intestinal viscosity and improved energy utilization through depolymerization of soluble non-starch polysaccharides. Considering that nutrients exist in a complex matrix involving starch and non-starch polysaccharides, protein, lipids, minerals, and vitamins, laying hens could also benefit from potential additive and synergistic effects accrued from adopting defined feed enzyme combinations. The incorporation of gut-health-promoting feed additives (pre, pro, syn- and postbiotics, phytogenics, organic acids) optimizes feed nutrient utilization by inducing immuno-stimulatory, antimicrobial, and antioxidant activities, modulating gut immune function, and microbial balance and population. Hen responses to feed additives are context-dependent and highly variable due to various factors, including rearing system, age, breed, health status, environmental factors, feed composition and quality, and management. However, on balance, feed additive products with proven efficacy and financial value are recommended for inclusion in laying hen diets; and could potentiate optimized performance and egg quality, reduced feed costs, improved animal welfare and skeletal health, and reduced environmental stress due to nutrient excretion, thereby improving the economic and environmental sustainability of hen egg production. Strategic application of feed additive combinations could potentiate additive and synergistic responses.

Machine learning models were developed to predict the degree of microbial quality of beef by a non-destructive method using a near-infrared hyperspectral imaging system. Beef was stored under aerobic conditions at different temperature scenarios (refrigerated, thawed after freezing, or left at room temperature) for a period of 15 days to induce freshness change and microbial growth. Hyperspectral data cubes were obtained from a data acquisition system in a darkroom environment. The total aerobic bacteria (TAB) experiment was performed in the established meat science manner to provide reference values for the microbial contamination level of the sample. The region of interest designated as the red meat region was selected for spectral extraction. Regression models were developed to predict the TAB value from the extracted data. Partial least squares regression, support vector machine, artificial neural network, and one-dimensional convolutional neural network methods were employed to construct TAB prediction models. Chemical maps were also created for each developed model to visualize the performance of the model. The model development process concluded with the iteration of all previous steps at completely different times and with different beef samples, generating the data for verification and applying it to the developed model to evaluate its versatility. As a result of the development, it was confirmed that the microbial quality of beef can be predicted by models generated from hyperspectral data (Best validation R ² = 0.8593, RMSE = 0.6947). Accurate quality prediction helps livestock breeders develop and apply better husbandry practices, which ultimately leads to higher quality beef production.

This study was carried out to examine the effects of varying levels of β-mannanase supplementation in corn-soybean meal (SBM)-based diet on growth performance, nutrient digestibility, blood metabolites, and diarrhea incidence of weaning pigs. A total of 160 pigs with an initial body weight (BW) of 8.66 ± 0.060 kg were used in the experiment. Using a randomized complete block (RCB) design, they were assigned to 4 treatments with 5 replicates and 8 pigs per pen, considering sex and initial BW. Treatments for early (0-2 weeks) and late weaning phases (2-5 weeks) were as follows: β-Man0: corn-SBM-based basal diet + β-mannanase 0%; β-Man0.05: basal diet + β-mannanase 0.05%; β-Man0.1: basal diet + β-mannanase 0.1%; and β-Man0.15: basal diet + β-mannanase 0.15%. During the early weaning phase, average daily gain tended to increase when β-mannanase level increased (linear, p = 0.07). When β-mannanase level increased in the late weaning phase, the average daily feed intake tended to decrease (linear, p = 0.08), and gain to feed ratio (G:F ratio) increased (linear, p = 0.02). Throughout the whole experimental period, G:F ratio tended to increase as β-mannanase level increased (linear, p = 0.06). According to nutrient digestibility, crude fat digestibility increased when the β-mannanase level increased (linear, p = 0.04). Accordingly, the total protein and triglyceride concentration increased as β-mannanase level increased in the early weaning phase (linear, p = 0.01; p = 0.01). During the entire experimental period, the total cholesterol concentration increased significantly (linear, p < 0.01), whereas the high-density lipoprotein cholesterol and low-density lipoprotein cholesterol concentration increased with higher levels of β-mannanase (linear, p = 0.02; p = 0.02). Lastly, diarrhea incidence showed no significant variation during the early and late weaning phases according to β-mannanase levels. As the level of β-mannanase supplementation in the weaning pig diet increased, growth performance, nutrient digestibility, and blood metabolites showed some positive trends. Therefore, supplementing β-mannanase up to 0.15% in the diet of weaning pigs could enhance their productivity.

Alkaline phosphatase (ALP) is an enzyme present in various tissues and plays an important role in biochemical processes, by catalyzing the hydrolysis of organic phosphates and energy metabolism. Despite significant ALP activity in seminal plasma across species, its role in sperm function remains unclear. Several studies have revealed the important role of taurine in male reproductive functions, due to its antioxidant and membrane-stabilizing activity, and ability to enhance sperm quality. Therefore, this study examined the influence of taurine on ALP activity and pH stability in liquid boar semen during storage. Boar spermatozoa were exposed to different concentrations of ALP (0-5 IU/mL), and sperm motility, viability, acrosome integrity, and ALP activity were examined. In addition, liquid boar semen with varying concentrations of taurine (10-80 mM) was stored at 17°C for 7 days, and the ALP activity, pH level, and fertilization competence of spermatozoa were investigated through the storage period. Higher ALP activity was detected in fresh spermatozoa compared with capacitated spermatozoa. Motility, viability, and acrosome integrity decreased significantly in sperm incubated with 1-5 IU/mL ALP. An immunofluorescence assay revealed that ALP was localized on the acrosome, equatorial segment, and tail, and the fluorescence intensity indicated that ALP levels gradually decreased during storage. When the pH of liquid boar semen was maintained at 7.4 during storage, it showed higher ALP activity and sperm quality compared to sperm stored in a medium where pH was not maintained at a stable level. Also, when boar spermatozoa were stored in the diluent containing taurine, the pH and ALP activity were stable during the storage period. The generation of intracellular reactive oxygen species decreased in sperm stored with taurine, and higher levels of sperm motility and viability were observed. The expression of mRNA associated with fertilization competence was higher in the sperm stored with 40 mM taurine compared to that of sperm stored without taurine. Thus, it can be concluded that ALP activity and pH stability are crucial for maintaining sperm quality during liquid boar semen storage, and these factors can be regulated by the addition of taurine, suggesting its applicability in assisted reproductive techniques in mammals.

Developmental patterns of the gut microbiota are important for improving chicken health and productivity. However, the influence of litter and litter microbes on cecal microbiota is still unclear. This study aimed to identify broiler cecal microbiota at different ages according to litter usage in cage (without litter) and conventional (with litter) conditions. The cecal contents of the broilers from each group were collected from 1-5 wk. The development and function of the gut microbiota were evaluated using 16S rRNA gene sequencing. The final body weight of the chickens was higher in the cage group than that in the conventional group. In particularly, α-diversity was higher at 3 wk than that at 1 wk. The phyla Firmicutes predominated at 3 wk. In contrast, the abundance of Bacteroidetes and fibrinolytic bacteria increased significantly at 1 and 2 wk compared to that at 3 and 5 wk. Corynebacterium was the most abundant genus in the conventional group after 3 wk. In conclusion, the cecal microbiota are influenced by environmental factors, such as cage, which improves the chicken gut environment.