Journal of Animal Science and Technology最新文献

This study investigates the bioconversion efficiency and nutrient accumulation in black soldier fly (BSF; Hermetia illucens), focusing on the effects of feeding on two different substrates (tofu by-products and food waste) and harvesting at two developmental stages (larvae and prepupae) within a 2 × 2 factorial arrangement. The growth performance, conversion efficiency, nutrient composition, amino acid profile, fatty acid composition, and nutrient composition of BSF meal were assessed. Results indicated that BSF reared on tofu by-products exhibited superior weight gain compared to those fed food waste, with significant enhancements observed in weight, length, and width upon harvesting at the prepupae stage. Moreover, tofu by-products promoted higher bioconversion rates, protein conversion efficiency, and lipid yield, while food waste favored lipid conversion. Analysis of nutrient composition revealed higher crude protein content in BSFs fed tofu by-products, with elevated levels of crude protein, ether extract, and chitin in prepupae-stage BSFs. Higher concentrations of isoleucine, leucine, and tryptophan were observed in tofu by-product-fed BSF. Conversely, BSFs harvested at the prepupae stage exhibited increased levels of threonine, alanine, and tyrosine, regardless of substrate. Higher proportions of α-linolenic acid (C18:3n3) and docosahexaenoic acid (C22:6n3) were observed in tofu by-product-fed BSF. Conversely, BSF harvested at the larval stage displayed higher levels of saturated fatty acids, including lauric acid (C12:0) and myristic acid (C14:0). In conclusion, tofu by-products emerged as a promising substrate for enhancing essential amino acid and unsaturated fatty acid content in BSF, while harvesting at the prepupae stage offered advantages in nutrient density and storage stability of the harvested biomass.

This study was conducted to measure the seasonal concentrations of particulate matter (PM) and ammonia (NH₃) emissions in laying hens performed according to the Verification of Environmental Technologies for Agricultural Production (VERA) Test Protocol and to calculate corresponding emission factors. During the winter and summer, the concentration of emitted PM₁₀ was high at 391.6 μg/m³ and low at 223.7 μg/m³, respectively, whereas that of PM_2.5 was high at 50.4 μg/m³ and 62.8 μg/m³ in the winter and spring, respectively. Furthermore, the concentration of emitted NH₃ was high at 9.33 and 8.37 ppm during winter and spring, respectively. The annual average emission concentrations for PM₁₀ and PM_2.5 were 323.5 and 49.6 5 μg/m³, respectively, whereas that for NH₃ was 5.75 ppm. The emission factors of PM₁₀ and PM_2.5 were highest in summer and lowest in winter; and those in fall were higher than those in spring. Similarly, the highest and lowest NH₃ emission factor values were recorded in the summer and winter, respectively. The annual emission factors of PM₁₀, PM_2.5, and NH₃ were 0.027, 0.0045, and 0.383 kg/head/year, respectively. Our finding in this study highlight the importance of monitoring for the effective management of PM and NH₃ emissions that occur over short time periods and indicate that the ventilation volume should also be considered on a seasonal basis.

This study indicated that dietary natural phytoncide feed additives altered immune-related serum parameters and serum metabolites in Hanwoo bulls. Cypress (CYP) and mugwort (MUG) extracts were supplemented at 0.5 mg/kg of concentrate diet for 90 days. A total of 15 bulls with initial body weights of 196.00±5.33 kg (control), 196.00±3.91 kg (CYP), and 196.00±3.31 kg (MUG) were used in a 90-day feeding experiment. Changes in serum immunological parameters were analyzed following a lipopolysaccharide (LPS) challenge. To minimize stress, a jugular vein catheter was installed in each animal, and animals were acclimated for 24 hours before sampling. Blood samples were collected 13 times at 30-minute intervals after the third sampling point, following intravenous injection of LPS (1 µg/kg bodyweigth). Serum albumin (ALB), glucose (GLU), total protein (TP), triglycerides (TG), inorganic phosphorus (IP), non-esterified fatty acids (NEFA), cortisol, and proinflammatory cytokines including interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were analyzed using standard procedures. After LPS injection, serum GLU and TG levels increased (p > 0.05), whereas serum NEFA levels decreased (p < 0.05). Neither serum GLU nor TG levels were significantly affected by phytoncide supplementation. Proinflammatory cytokines such as IL-1β, IL-6, and TNF-α increased over time after LPS injection; however, serum TNF-α levels tended to be lower in the phytoncide-treated groups compared to the CON (p > 0.05). Additionally, serum cortisol levels were lower in phytoncide-treated groups than in the CON following LPS challenge, although the difference was not statistically significant (p > 0.05). In conclusion, dietary supplementation with natural phytoncide modified serum metabolite profiles and contributed to a reduction in proinflammatory cytokine responses in Hanwoo bulls under LPS-induced immune stress.

This study investigated the effects of dietary crude protein (CP) levels on body weight (BW), laying performance, egg quality, and nitrogen (N) balance in laying hens from 18 to 62 weeks of age. A total of 84 Hy-Line Brown hens at 18 weeks old were randomly assigned to two groups, each with six replicates. The control group (CON) received diets with 17.5%, 16.5%, 15.5%, and 14.5% CP from weeks 18-38, 39-46, 47-54, and 55-62, respectively. The reduced protein group (RP) was fed diets with 1.5% less CP than the CON group during the same periods (16.0%, 15.0%, 14.0%, and 13.0%, respectively). The RP group showed significantly lower BW from weeks 30-62 (p < 0.05) and reduced hen-day egg production during weeks 18-38 and 54-62 (p < 0.05). Egg weight (EW) was significantly higher in the CON group than the RP group during weeks 54-62 (p = 0.003), and feed efficiency was also reduced in the RP group across multiple phases (p < 0.05). At week 38, Haugh units (HU) were lower in the RP group (p = 0.034), and yolk color was lighter at week 62 (p = 0.006). N balance parameters showed that the RP group had significantly lower N intake at weeks 46, 54, and 62 (p < 0.01), and N excretion was reduced throughout the trial (p < 0.05). Total N retention was lower in the RP group at weeks 26, 38, 54, and 62 (p < 0.05), and N retained in eggs was also reduced at weeks 26, 38, and 62 (p < 0.05). In summary, lowering dietary CP levels by 1.5% decreased N excretion, suggesting environmental benefits. In summary, reduction of dietary CP levels by 1.5% reduced N excretion but also compromised BW, laying performance, HU, and N retention. These findings highlight the need for further refinement of amino acid formulations to achieve both environmental and production goals.

The current study aimed to estimate the standardized ileal digestible (SID) calcium (Ca) and phosphorus (P) requirements of broiler chickens based on response surface methodology (RSM). Nine experimental diets were formulated with different SID Ca and P concentrations (2.80 and 5.50, 3.44 and 4.44, 3.44 and 6.56, 5.00 and 7.00, 5.00 and 5.50, 5.00 and 4.00, 6.56 and 4.44, 6.56 and 6.56, and 7.20 and 5.50 g/kg, respectively). A total of 480 10-day-old Ross 308 male broilers were weighed and randomly assigned to nine treatments based on body weight. Each treatment had five replicates, except for the central treatment (5.00 g/kg Ca and 5.50 g/kg P), which had eight replicates with 10 birds per pen. On day 21, body weight and feed leftovers were recorded to calculate body weight gain (BWG) and the gain-to-feed ratio (G:F). Left tibia bones were also collected for compositional analysis and bone mineral density (BMD) assessment. Response surface analysis revealed significant quadratic models for all criteria. The maximum BWG was estimated at 5.13 and 5.74 g/kg for SID Ca and P, respectively. The maximum G:F was observed when 6.41 and 7.00 g/kg of SID Ca and P were used, respectively. Multi-objective optimization analysis demonstrated that 6.02 g/kg of SID Ca and 6.61 g/kg of SID P were required to achieve both optimal BWG and G:F. Furthermore, the ideal SID Ca and P concentrations for optimal tibia ash, tibia Ca, tibia P, and BMD were estimated at 7.20 and 7.00 g/kg, 5.75 and 5.87 g/kg, 7.20 and 7.00 g/kg, and 7.20 and 6.96 g/kg, respectively. Multi-objective optimization indicated that 6.50 and 6.83 g/kg of SID Ca and P, respectively, are required to achieve optimal growth performance and bone mineralization. This study's findings suggest that RSM is a feasible and effective approach to determining the optimal SID Ca and P requirements of broiler chickens, as it efficiently evaluates multiple factors while considering several response criteria.

Asthma, a prevalent respiratory condition in animal science, involves bronchial inflammation, leading to symptoms like coughing and difficulty breathing. Mast cells and macrophages, pivotal immune cells, contribute to the inflammatory response triggered by various factors. Extracellular vesicles (EVs), including exosomes, play crucial roles in intercellular communication and have been implicated in murine asthma. We hypothesize that murine asthma-derived EVs modulate immune cell responses in animals. Our study investigates the role of these EVs in immune cell activation, shedding light on asthma pathogenesis. Using a murine asthma model induced by ovalbumin (OVA), we assessed serum EVs via Nanoparticle Tracking Analysis (NTA). Serum EVs from normal and asthmatic mice were subjected to Enzyme-linked immunosorbent assay (ELISA) and proteomic analysis for component identification. Elevated EV concentration and inflammatory cytokines, such as Interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α, were found in asthma-derived EVs. Additionally, variations in immunoglobulin light chain types were identified. Surprisingly, murine asthma EVs failed to activate T lymphocytes, B lymphocytes, eosinophils, and macrophages but stimulated mouse bone marrow-derived mast cells (mBMMCs) via enhanced degranulation and MAP kinase phosphorylation. These results suggest murine asthma-derived EVs as potential therapeutic targets for managing asthmatic symptoms in animal science. Further research into their mechanisms and clinical applications is warranted.

Plumage color is an important economic trait in chickens and is mainly affected by genetic factors than environmental factors. This study aimed to detect the single-nucleotide polymorphisms (SNPs) in CDKN2A, MTAP, and PMEL genes and explore their influence on plumage color variation in chickens. We used 428 chicken blood samples, consisting of all-black: 62, all-white: 246, and black and white barred: 120 chickens of F2 population produced from crossing the F1 progenies. The F1 population was produced by crossing Yeonsan Ogye and White Leghorn. The SNPs in the CDKN2A, MTAP, and PMEL genes were initially detected by sequencing. PACE Genotyping technology was used for genotyping and results were observed for a synonymous SNP, rs316391660C/T of the MTAP gene, missense SNPs, rs312616138A/G and rs14684281T/C of the PMEL gene. The association test between the genotypes in MTAP (SNP: rs316391660C/T) and PMEL (SNP: rs14684281T/C) genes was performed by Chi-square test while Fisher's exact test to evaluate association the genotypes of Please italize PMEL gene (SNP: rs312616138A/G) with plumage color variations. The missense SNP, rs1058656732C/T in CDKN2A gene was monomorphic and could not be used for the association test. There was a significant (p < 0.05) association between genotypes of MTAP and PMEL genes with the three plumage color variations: all-black, all-white, and black and white barred. Our results confirm the genotype effects of the PMEL gene on the dominant white plumage color, and suggest that the synonymous SNP (rs316391660C/T) of the MTAP gene could be used as a genetic marker for the breeding of chickens with black-and-white barred plumage.

South Korea recently revised its livestock regulations to enforce mandatory group housing for pregnant sows beyond six gestation weeks until 2030. However, group housing of pregnant sows can influence their social hierarchy and feed competition, thereby affecting their reproductive performance and welfare. Although governing regulations of minimum space requirements for group-housed pregnant sows have not yet been established in South Korea, a minimum space of 1.9 m² per sow is estimated to be necessary. Therefore, this study investigated the effects of space allowance (SA; 1.9 m², 2.3 m²) during pregnancy and social training (ST; -, +) during the growing period on the productivity and welfare of primiparous sows. Thirty-six gilts were divided into four groups based on space allowance during gestation and social training during the growing period: 1) SA 1.9 m², non-ST (-), 2) SA 1.9 m², ST (+), 3) SA 2.3 m², non-ST (-), and 4) SA 2.3 m², ST (+). Measurements were basic performance, reproductive performance, colostrum composition, lameness score, and number of skin lesions of primiparous sows. The sow group in SA 1.9 m² had higher (p < 0.05) body weight during farrowing crate relocation, litter weight of total litter, stillbirth, and alive born, and number of skin lesions during the overall period of group housing than that in SA 2.3 m². However, there were no effects of SA on colostrum composition and lameness score of sows. The sow group with ST had higher (p < 0.10) litter size of total born and alive born and fewer (p < 0.05) number of skin lesions during the overall period of group housing than that without ST. However, no effects of ST were found on sow performance, colostrum composition, and lameness score. In addition, there were no interaction effects between SA and ST on all measurements in this study. In conclusion, primiparous sow aggression may be reduced by increasing space allowance during gestation with social training during the growing period.

Stocking density is a crucial parameter that impacts animal welfare, performance, and economic returns for producers. In our current investigation, we explored the influence of stocking density on the growth performance, litter quality, footpad dermatitis, and corticosterone concentrations in broiler chickens. Low and high stocking densities were defined as 16.7 birds/m² (certified for animal welfare, n = 32,000; initial body weight [BW] = 42.1±0.32 g; Arbor Acres) and 20.3 birds/m² (commercial farm, n = 32,000; initial BW = 42.9±0.31; Arbor Acres), respectively. A basal diet typical of commercial standards was developed to meet or surpass the nutritional requirements outlined by the National Research Council (NRC) for broiler chickens. The control group was housed for 29 days to compare productivity and animal welfare indicators in high stocking density (20.3 birds/m²) as per livestock industry regulations and low stocking density (16.7 birds/m²) according to animal welfare standards. During the grower periods (21-29 days) and the overall period (0-29 days) of the experiment, feed intake and BW were lower in the lower stocking density group (p < 0.05). Additionally, the feed conversion ratio significantly improved at the lower stocking density. By day 29, the average footpad dermatitis score, litter moisture, NH₃ concentration, and feather cleanliness were significantly higher at the higher stocking density. Corticosterone concentrations decreased by 2.35% at the lower stocking density by day 29. These results indicate that decreasing stocking density enhances the welfare and growth performance of broiler chickens, as indicated by decreases in litter moisture, footpad dermatitis, and corticosterone concentrations.

Spores present in milk survive heat treatments and can persist during downstream processing. In Korea, the development of the dairy industry is also growing. However, studies related to the distribution and diversity of spore-forming bacteria for the quality control of raw milk and dairy products are insufficient. This study aimed to evaluate the contamination levels of spore-forming species in raw milk derived from five dairy farm environments in Korea. The isolated strains were also identified using 16S rRNA sequencing and characterized based on the environmental factors in farms, which affect raw milk production. Representative spore-forming bacteria communities in the samples include Bacillaceae, Lachnospiraceae, Paenibacillaceae, and Caryophanaceae at the family level, and Bacillus, Clostridium, and Paenibacillus were the most diverse and predominant at the genus level. A total of 1,102 isolates of 16 genera could be assigned to the genus Bacillus (67.3% and 742 isolates), Clostridium (12.3% and 135 isolates), Paenibacillus (9.3% and 102 isolates), and Oceanobacillus (5.9% and 65 isolates). Among 173 species, the prominent members were Bacillus licheniformis, Bacillus kochii, Bacillus clausii, and Clostridium sporogenes. Twenty-seven spore-forming species (Bacillus licheniformis, Bacillus coagulans, Bacillus sonorensis, Bacillus sporothermodurans, Clostridium sporogenes, Clostridium tyrobutyricum, and Paenibacillus validus) detected in raw milk were the same species found in the dairy farm environments. Our result clearly shows that specific provinces have distinct proportions of spore formers that may cause spoilage of raw milk and milk products, such as cheese and yogurt. The biodiversity of spore-forming bacteria in the dairy farms were greatly influenced by several factors such as dairy farm conditions and milking environments. Recommending proper management of hygienic and production practices, including strengthening laws and implementing Hazard Analysis and Critical Control Points (HACCP) principles, would be effective in eradicating contamination during the production of raw milk.