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Objective: Subclinical mastitis decreases milk production and quality, despite the normal appearance of the mammary glands and milk. Herein, we aimed to investigate changes in factors monitored via automatic milking systems (AMS) prior to subclinical mastitis onset and identify differences in hematological and biochemical parameters and milk composition at subclinical mastitis onset., Methods: Thirty-two Holstein cows were divided into two groups according to somatic cell counts (SCC) from AMS and milk composition analysis and the California mastitis test (CMT): healthy cows (controls [CON], n = 16, SCC <500×103 cells/mL and negative for CMT) and cows with subclinical mastitis (SCM, n=16, SCC ≥500×103 cells/mL and positive for CMT). Eventually, 121 milk samples from the CON ([mCON], n = 60) and SCM ([mSCM], n = 61) groups were obtained; SCM samples were categorized as those from non-inflamed (mNQ) or subclinically-inflamed (mIQ) quarters. We evaluated AMS factors; hematological, biochemical, and milk composition parameters; and bacterial isolation., Results: In cows with SCM, milk yield decreased, and electrical conductivity (EC) changed before disease onset. Milk EC decreased in mNQ although increased in mIQ (p<0.05). The SCM group had higher globulin levels and lower basophil counts; albumin-to-globulin ratio; and total cholesterol, albumin, and blood urea nitrogen levels than the CON group (p<0.05). The mIQ group had higher SCC but lower levels of lactose and milk solids-notfat than those in the mCON and mNQ groups (p<0.05). The mCON group had higher levels of milk non-protein nitrogen than the mNQ group (p<0.05). Opportunistic mastitis pathogens were isolated in the mIQ group., Conclusion: Changes in milk yield and EC measured using AMS occurred prior to subclinical mastitis, which may be associated with variation in basophil counts; albumin-toglobulin ratio; and total cholesterol, albumin, blood urea nitrogen, globulin, SCC, milk lactose, and milk solids-not-fat levels at disease onset. These findings provide new insights into early-stage subclinical mastitis.

Objective: In Korea, dairy cattle breeding programs have historically prioritized productive, conformation traits, leading to positive improvements, yet reproductive traits have lagged in development. This study was conducted to develop the breeding program of key reproductive traits in the Korean dairy cattle population., Methods: Utilizing data from 7,596 farms and over seven million observations, we conducted quality control to rectify manual entry errors and selected traits in line with international genetic evaluation standards. Traits analyzed included heifer conception rate (HCR), interval from calving to first insemination (CF), cow conception rate (CCR), interval from first to last insemination (FL), and days open (DO). Genetic parameters were estimated using a single trait animal model for HCR and a multiple lactation animal model for CF, CCR, FL, and DO, considering contemporary group of herd-insemination year, insemination month, and monthly age as fixed effects., Results: Results showed low heritability estimates, ranging from 0.007 to 0.035 across different traits and lactations. Theoretical reliability appears to be low on average due to the influence of heritability, but it showed sufficiently high reliability in some sires (over 0.8). In terms of genetic and phenotypic trends, capacity for reproductive traits declined for a long time until around 2014. In recent individuals, improved trend can be found., Conclusion: This study addressed the critical need for enhancing reproductive efficiency to complement the existing breeding goals, thereby supporting sustained economic viability in the dairy industry. The results underscore the need for improved data quality and methodological adjustments for reproduction records to enhance the genetic evaluation of dairy cattle in Korea.

Objective: The objective was to investigate the effects of dietary benzoic acid (BA) on nitrogen (N) balance, urinary pH, slurry pH, and odorous compounds in feces and slurry of pigs., Methods: Twelve barrows with an initial body weight of 56.2±2.6 kg were individually housed in metabolism crates. The animals were allocated to a replicated 6×4 incomplete Latin square design with 12 animals, 6 experimental diets, and 4 periods, resulting in 8 observations per treatment. The basal diet consisted mainly of corn, soybean meal, and rapeseed meal. Benzoic acid was supplemented to the basal diet at 0.5%, 1.0%, 1.5%, 2.0%, or 2.5% at the expense of corn starch. Each period consisted of a 4-day adaptation period and a 24-h collection period for slurry, followed by a 4-day collection period for feces and urine. On day 5, feces and urine were collected for 24 h and mixed to obtain slurry samples., Results: The daily digested N linearly increased (p<0.05) with increasing BA supplementation. Supplemental BA lowered urinary pH (p<0.001) and slurry pH (p<0.05) in a linear and quadratic manner. In the fecal samples, the concentrations of acetate, propionate, butyrate, and skatole linearly decreased (p<0.05) with supplemental BA. In the slurry samples, the concentrations of butyrate, isovalerate, and skatole linearly decreased (p<0.05) by supplemental BA., Conclusion: In conclusion, supplemental benzoic acid has the potential to improve nitrogen digestion in a dose-dependent manner for pigs. Additionally, dietary benzoic acid lowers urinary pH, slurry pH, and concentrations of odorous compounds in pig feces and slurry.

Objective: We investigated genetic parameters of calving ease (CE) using several animal models in Korean Holstein and searched for suitable models for routine evaluation of CE., Methods: Two phenotypic datasets of CE (DS5 and DS10) on first-parity Korean Holstein calves were prepared. DS5 and DS10 included at least 5 and 10 CE records per herd-year level and comprised 117,921 and 80,389 observations, respectively. The CE phenotypes ranged from 1 to 4, from a normal to extreme difficulty calving scale. The CE was defined as a trait of the calf. The BLUPF90+ software was used for (co)variances estimation through four animal models with a maternal effect (M1 to M4), where all models included effects of a fixed calf-sex, a fixed dam calving age (covariate), and one or more fixed contemporary group (CG) terms. The CG effects were different across models-a herd-year-season (M1, HYS), a herd-year and year-season (M2, HY+YS), a herd-year and season (M3, HY+S), and a herd and year-season (M4, H+YS)., Results: Direct heritability (h2) estimates of CE ranged from 0.005 to 0.234 across models and datasets. Maternal h2 values were low (0.001 to 0.090). Genetic correlations between direct and maternal effects were strongly negative to lowly positive (-0.814 to 0.078), further emphasizing its importance in CE evaluation models. These genetic parameter estimates also indicate slower future selection progress of CE in Korean Holsteins. The M1 fitted many levels with fewer observations per level deriving unreliable parameters, and the M4 did not account for confounded herd and animal structures. The M2 and M3 were deemed more realistic for implementation, and they were better able to account for data structure issues (incompleteness and confounding) than other models., Conclusion: As the pioneering study to employ animal models in Korean Holstein CE evaluation, our findings hold significant potential for this breed's future and routine evaluation development.

Objective: This study evaluated the effects of increased levels of dietary total digestible nutrient (TDN) and crude protein (CP) using protected fat (PF), soybean meal (SB), and heat-treated soybean meal (HSB) on performance, physiological parameters, and behavioral measurements of early-fattening Hanwoo steers under heat stress conditions., Methods: Thirty-six steers (480.9±58.6 kg, 15.9±1.4 months) were assigned to 4 treatments: control (TDN 75%, CP 15%, rumen degradable protein [RDP]:rumen undegradable protein [RUP] = 62:48); PF (TDN 82.5%, CP 15%, RDP:RUP = 62:48); PF+SB (TDN 82.5%, CP 16.5%, RDP:RUP = 62:48); and PF+SB+HSB (TDN 82.5%, CP 16.5%, RDP:RUP = 48:52) for a total of 16 weeks with division of 4 weeks. The average temperature-humidity index (THI) was 82.9 (1st; moderate), 76.9 (2nd; mild), 70.9 (3rd; comfort), and 65.8 (4th period; comfort)., Results: Dry matter intake during whole period did not differ among treatments but decreased by 34% and 19%, respectively during 1st and 2nd compared to 4th. Average daily gain (ADG) of PF+SB+HSB was higher (p<0.05) than that of control during the 1st period, and those of both PF+SB and PF+SB+HSB were higher (p<0.05) than Control during the 2nd. The ADG during whole period was in the order of PF+SB+HSB (1.23), PF+SB (1.18), PF (1.11), control (0.98 kg/d) (p<0.05). As THI increased, rectal temperature and all blood parameters increased, while blood glucose levels decreased (p<0.05). Behavioral changes during 1st period compared to 3rd included decreases in lying (24%), walking (48%), and eating (40%), and increases in total standing (50%) and drinking (43%) (p<0.05). Rumination during standing was 38% higher, and rumination during lying was 32% lower (p<0.05)., Conclusion: This study demonstrates 10% of increased levels of dietary TDN using PF and CP considering RUP can prevent performance reduction in early-fattening of heatstressed Hanwoo steers and have positive effects on performance recovery from post-heat stress.

Objective: This study aimed to investigate effects of apparent metabolizable energy (AMEn) levels in diets on productivity, fat deposition, and biochemical parameters of Woorimatdag1 (WMD1) breeder pullets., Methods: A total of 240 four-week-old WMD1 breeder pullets were divided into four dietary groups with five replicates (12 birds per replicate). These groups had the following dietary energy levels: standard ME (SME), SME-200, SME-100, and SME+100 (diets containing 2,800, 2,600, 2,700, and 2,900 kcal AMEn/kg, respectively). These pullets were provided with diets and water ad libitum until 16 weeks old., Results: Weight gain was significantly (p < 0.05) higher in SME-100, SME, and SME+100 groups than in the SME-200 group. SME+100 and SME groups exhibited significantly (p < 0.05) improved feed conversion ratio compared to the SME-200 group. Laying ages of 30% egg production occurred significantly (p < 0.05) earlier in SME-100, SME, and SME+100 groups than in the SME-200 group. SME and SME+100 groups had significantly (p < 0.05) higher liver fat (%) than the SME-200 group. Additionally, the SME+100 group had higher (p < 0.05) abdominal fat (%) than other groups. However, blood parameters were not significantly different among dietary groups., Conclusion: SME-100 (2,700 kcal AMEn/kg) might be suitable for improving productivity and fat deposition of WMD1 breeder pullets.

Objective: Yellow Korean native chicken (KNC-Y) is one of the five pure Korean indigenous chicken breeds that were restored through a government project in 1992. KNC-Y is recognized for its superior egg production performance compared to other KNC lines. In this study, we performed runs of homozygosity (ROH) analysis to discover selection signatures associated with egg production traits in the KNC-Y population., Methods: A total of 675 DNA samples from KNC-Y were genotyped to generate single nucleotide polymorphism (SNP) data using custom 60K Affymetrix SNP chips. ROH analysis was performed using PLINK software, with predefined parameters set for the analysis. The threshold of ROH island was defined as the top 1% frequency of SNPs withing the ROH among the population., Results: In the KNC-Y population, a total of 29,958 runs of homozygosity (ROH) fragments were identified. The average total length of ROH was 120.84 Mb, with each ROH fragment having an average length of 2.71 Mb. The calculated ROH-based inbreeding coefficient (FROH) was 0.13. Furthermore, we revealed the presence of ROH islands on chromosomes 1, 2, 4, 5, 7, 8, and 11. Within the identified regions, a total of 111 genes were annotated, and among them were genes related to economic traits, including PRMT3, ANO5, HDAC4, LSS, PLA2G4A, and PTGS2. Most of the overlapping quantitative trait locus regions with ROH islands were found to be associated with production traits., Conclusion: This study conducted a comprehensive analysis of ROH in the KNC-Y population. Notably, among the findings, the PTGS2 gene is believed to play a crucial role in influencing the laying performance of KNC-Y.

Objective: Carnosine and anserine affect the meat flavor. The contents of carnosine and anserine in meat are affected by genetic and environmental factors. This study aimed to discover the single-nucleotide polymorphisms (SNPs) in the histamine-N-methyl transferase (HNMT) and histamine-N-methyl transferase-like (HNMT-like) genes and to associate them with the content of carnosine and anserine in Korean native chickenred brown line (KNC-R)., Methods: This study used a total of 384 birds (males, n = 192; females, n = 192) aged 10 weeks old, for genotyping HNMT and HNMT-like genes. One synonymous SNP (rs29009298C/T) of the HNMT gene was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods whereas four missense SNPs (rs734406537G/A; rs736514667A/G; rs15881680G/A and rs316765035T/C) of the HNMT gene, and one missense SNP rs737657949A/C of the HNMT-like gene were genotyped by PCR allele competitive extension (PACE) genotyping technology. Two-way analysis of variance of the R program was used to associate HNMT genotypes with the contents of carnosine and anserine in KNC-R chickens., Results: There were significant associations (p<0.05) between the genotypes of the synonymous SNP:rs29009298C/T, missense SNP rs736514667A/G of the HNMT gene and the content of carnosine in KNC-Rs. This study also reported the sex effect on the carnosine content, where females had more content of carnosine compared to that of male KNC-R., Conclusion: Two SNPs (synonymous: rs735769522C/T) and missense: rs736514667A/G) in the HNMT gene might be used as genetic markers in the selection and breeding of chickens with better taste and high-flavored meat.

Objective: The aim of this study was to evaluate the effects of different levels of wheat inclusion on growth performance, glycolipid metabolism, and tibial properties of broiler chickens., Methods: A total of 480 1-d-old male broiler chickens were initially fed identical starter diets until d 10. Subsequently, they were divided into 3 treatments consisting of 8 replicates with 20 birds per replicate, i.e., 1) low-level wheat addition group, with wheat ratios of 15% and 25% during the grower and finisher periods, respectively; 2) medium-level wheat inclusion group, incorporating 30% and 40% wheat in the grower and finisher diets, respectively; and 3) high-level wheat addition group, containing 55.8% and 62.4% wheat in the grower and finisher diets, until d 39., Results: When compared to the low- and medium-level wheat diet, the high-level wheat inclusion in the diet increased feed intake and reduced the feed conversion ratio (both p<0.01), which was accompanied by a longer jejunum (p=0.031). Meanwhile, the high-level addition of wheat displayed a decreased abundance of Ruminococcin, Bacteroidetes, and Lactobacillus than the low-wheat group. With the increase of the proportion of wheat treatment, the contents of cholesterol, triglyceride, and high-density lipoprotein cholesterol were elevated in serum, whereas the concentration of serum C-terminal cross-linked telopeptide of type I collagen, a bone resorption marker, was decreased. In addition, the diet with medium and high levels of wheat improved the yield load of tibia, along with comparable bone dimension and weight., Conclusion: The medium- and high-level wheat additions increased serum glycolipid deposition and enhanced tibial mechanical properties, whereas the high-level wheat diet compromised the growth performance of broiler chickens, which might be associated with the alteration of gut microbiota.

Objective: MicroRNAs (miRNAs) are endogenous non-coding RNAs that can play a role in the post-transcriptional regulation of mammalian preadipocyte differentiation. However, the precise functional mechanism of its regulation of fat metabolism is not fully understood., Methods: We identified bta-miR-365-3p, which specifically targets the 3' untranslated region (3'UTR) of the FK506-binding protein 5 (FKBP5), and verified its mechanisms for regulating expression and involvement in adipogenesis., Results: In this study, we found that the overexpression of bta-miR-365-3p significantly decreased the lipid accumulation and triglyceride content in the adipocytes. Compared to inhibiting bta-miR-36 5-3p group, overexpression of bta-miR-365-3p can inhibit the expression of adipocyte differentiation-related genes C/EBPα and PPARγ. The dualluciferase reporter system further validated the targeting relationship between bta-miR-365-3p and FKBP5. FKBP5 mRNA and protein expression were detected by quantitative real-time polymerase chain reaction and Western blot. Overexpression of bta-miR-365-3p significantly down-regulated FKBP5 expression, while inhibition of bta-miR-365-3p showed the opposite, indicating that bta-miR-365-3p negatively regulates FKBP5. Adenosine 5'-monophosphate (AMP)-activated protein kinase/mammalian target of rapamycin (AMPK/mTOR) signaling pathway is closely related to the regulation of cell growth and is involved in the development of bovine adipocytes. In this study, overexpression of bta-miR-365-3p significantly inhibited mRNA and protein expression of AMPK, mTOR, and SREBP1 genes, while the inhibition of bta-miR-365-3p expression was contrary to these results. Overexpression of FKBP5 significantly upregulated AMPK, mTOR, and SREBP1 gene expression, while inhibition of FKBP5 expression was contrary to the above experimental results., Conclusion: In conclusion, these results indicate that bta-miR-365-3p may be involved in the AMPK/mTOR signaling pathway in regulating Yanbian yellow cattle preadipocytes differentiation by targeting the FKBP5 gene.

Objective: This study aimed to determine the effects of increasing energy and protein levels in diets by including protected fat (PF), glycerol (GL), and soybean meal (SBM) on growth performance, physiological parameters, carcass characteristics, and behavioral measurements of late-fattening Hanwoo steers under heat stress conditions., Methods: Thirty-six steers (initial body weight, 724.9±58.3 kg; age, 25.5±0.4 month) were assigned into control (total digestible nutrient [TDN] 76%, crude protein [CP] 15%), PF (TDN 83.6%, CP 15%), PF+GL (TDN 83.6%, CP 15%) and PF+GL+SBM (TDN 83.6%, CP 16.5%) by randomized complete block design for a total of 16 weeks with division of 4-week periods. The average temperature-humidity index was 87.0 (1st period; severe), 82.8 (2nd; moderate), 71.4 (3rd; comfort), and 68.1 (4th; comfort)., Results: The dry matter intake (DMI) showed no treatments differences during the whole experiment. However, DMI in 1st and 2nd period decreased by approximately 30% and 10% compared to 4th period, respectively. Higher average daily gain and feed conversion ratio were noted for treatments compared to control at both 1st and 2nd period (p<0.05). There were no treatment effects on rectal temperature (RT), cortisol, and behaviors during the entire experiment. However, both RT and cortisol in 0, 1st and 2nd period were higher than those of 3rd and 4th period (p<0.05). Carcass yield and grade remained unaffected by increasing TDN and CP levels. Behavioral changes in the hot season (1st period) included reduced lying (43%), increased standing (48%), decreased walking (62%), and decreased eating (38%) (p<0.05), with an increase in drinking by 54%. Rumination during standing was 53% higher, while rumination during lying was about 33% lower compared to the post-hot season (3rd period) (p<0.05)., Conclusion: Dietary supplementation of protected fat in late-fattening Hanwoo steers under heat stress had a positive effect on preventing a reduction in performance.

Objective: Jining Grey goat is a local Chinese goat breed that is well known for its high fertility and excellent meat quality but shows low meat production performance. Numerous studies have focused on revealing the genetic mechanism of its high fertility, but its highlighting meat quality and muscle growth mechanism still need to be studied., Methods: In this research, an integrative analysis of the genomics and transcriptomics of Jining Grey goats compared with Boer goats was performed to identify candidate genes and pathways related to the mechanisms of meat quality and muscle development., Results: Our results overlap among five genes (ABHD2, FN1, PGM2L1, PRKAG3, RAVER2) and detected a set of candidate genes associated with fatty acid metabolism (PRKAG3, HADHB, FASN, ACADM), amino acid metabolism (KMT2C, PLOD3, NSD2, SETDB1, STT3B, MAN1A2, BCKDHB, NAT8L, P4HA3) and muscle development (MSTN, PPARGC1A, ANKRD2). Several pathways have also been detected, such as the FoxO signaling pathway and Apelin signaling pathway that play roles in lipid metabolism, lysine degradation, N-glycan biosynthesis, valine, leucine and isoleucine degradation that involving with amino acid metabolism., Conclusion: The comparative genomic and transcriptomic analysis of Jining Grey goat and Boer goat revealed the mechanisms underlying the meat quality and meat productive performance of goats. These results provide valuable information for future breeding of goats.

Objective: The present work was conducted to evaluate suitable variables and develop prediction equations using chemical composition and physical characteristics for estimating standardized ileal digestibility (SID) of lysine (Lys) in full-fat soybeans (FFSB)., Methods: The chemical composition and physical characteristics were determined including trypsin inhibitor activity (TIA), urease activity (UA), protein solubility in 0.2% potassium hydroxide (KOH), protein dispersibility index (PDI), lysine to crude protein ratio (Lys:CP), reactive Lys:CP ratio, neutral detergent fiber, neutral detergent insoluble nitrogen (NDIN), acid detergent insoluble nitrogen (ADIN), acid detergent fiber, L* (lightness), and a* (redness). Pearson's correlation (r) was computed, and the relationship between variables was determined by linear or quadratic regression. Stepwise multiple regression was performed to develop prediction equations for SID of Lys., Results: Negative correlations (p<0.01) between SID of Lys and protein quality indicators were observed for TIA (r = -0.80), PDI (r = -0.80), and UA (r = -0.76). The SID of Lys also showed a quadratic response (p<0.01) to UA, NDIN, TIA, L*, KOH, a* and Lys:CP. The best-fit model for predicting SID of Lys in FFSB included TIA, UA, NDIN, and ADIN, resulting in the highest coefficient of determination (R2 = 0.94)., Conclusion: Quadratic regression with one variable indicated the high accuracy for UA, NDIN, TIA, and PDI. The multiple linear regression including TIA, UA, NDIN, and ADIN is an alternative model used to predict SID of Lys in FFSB to improve the accuracy. Therefore, multiple indicators are warranted to assess either insufficient or excessive heat treatment accurately, which can be employed by the feed industry as measures for quality control purposes to predict SID of Lys in FFSB.

Objective: This study aims to identify the significant regions and candidate genes of growth-related traits (adjusted backfat thickness [ABF], average daily gain [ADG], and days to 90 kg [DAYS90]) in Korean commercial GGP pig (Duroc, Landrace, and Yorkshire) populations., Methods: A genome-wide association study (GWAS) was performed using single-nucleotide polymorphism (SNP) markers for imputation to Illumina PorcineSNP60. The BayesB method was applied to calculate thresholds for the significance of SNP markers. The identified windows were considered significant if they explained ≥1% genetic variance., Results: A total of 28 window regions were related to genetic growth effects. Bayesian GWAS revealed 28 significant genetic regions including 52 informative SNPs associated with growth traits (ABF, ADG, DAYS90) in Duroc, Landrace, and Yorkshire pigs, with genetic variance ranging from 1.00% to 5.46%. Additionally, 14 candidate genes with previous functional validation were identified for these traits., Conclusion: The identified SNPs within these regions hold potential value for future markerassisted or genomic selection in pig breeding programs. Consequently, they contribute to an improved understanding of genetic architecture and our ability to genetically enhance pigs. SNPs within the identified regions could prove valuable for future marker-assisted or genomic selection in pig breeding programs.

Objective: This study aimed to assess the genetic parameters and accuracy of genomic predictions for twenty-four linear body conformation traits and overall conformation scores in Korean Holstein dairy cows., Methods: A dataset of 2,206 Korean Holsteins was collected, and genotyping was performed using the Illumina Bovine 50K single nucleotide polymorphism (SNP) chip. The traits investigated included body traits (stature, height at front end, chest width, body depth, angularity, body condition score, and locomotion), rump traits (rump angle, rump width, and loin strength), feet and leg traits (rear leg set, rear leg rear view, foot angle, heel depth, and bone quality), udder traits (udder depth, udder texture, udder support, fore udder attachment, front teat placement, front teat length, rear udder height, rear udder width, and rear teat placement), and overall conformation score. Accuracy of genomic predictions was assessed using the single-trait animal model genomic best linear unbiased prediction method implemented in the ASReml-SA v4.2 software., Results: Heritability estimates ranged from 0.10 to 0.50 for body traits, 0.21 to 0.35 for rump traits, 0.13 to 0.29 for feet and leg traits, and 0.05 to 0.46 for udder traits. Rump traits exhibited the highest average heritability (0.29), while feet and leg traits had the lowest estimates (0.21). Accuracy of genomic predictions varied among the twenty-four linear body conformation traits, ranging from 0.26 to 0.49. The heritability and prediction accuracy of genomic estimated breeding value (GEBV) for the overall conformation score were 0.45 and 0.46, respectively. The GEBVs for body conformation traits in Korean Holstein cows had low accuracy, falling below the 50% threshold., Conclusion: The limited response to selection for body conformation traits in Korean Holsteins may be attributed to both the low heritability of these traits and the lower accuracy estimates for GEBVs. Further research is needed to enhance the accuracy of GEBVs and improve the selection response for these traits.

Objective: Pig breeders cannot obtain phenotypic information at the time of selection for sow lifetime productivity (SLP). They would benefit from obtaining genetic information of candidate sows. Genomic data interpreted using deep learning (DL) techniques could contribute to the genetic improvement of SLP to maximize farm profitability because DL models capture nonlinear genetic effects such as dominance and epistasis more efficiently than conventional genomic prediction methods based on linear models. This study aimed to investigate the usefulness of DL for the genomic prediction of two SLP-related traits; lifetime number of litters (LNL) and lifetime pig production (LPP)., Methods: Two bivariate DL models, convolutional neural network (CNN) and local convolutional neural network (LCNN), were compared with conventional bivariate linear models (i.e., genomic best linear unbiased prediction, Bayesian ridge regression, Bayes A, and Bayes B). Phenotype and pedigree data were collected from 40,011 sows that had husbandry records. Among these, 3,652 pigs were genotyped using the PorcineSNP60K BeadChip., Results: The best predictive correlation for LNL was obtained with CNN (0.28), followed by LCNN (0.26) and conventional linear models (approximately 0.21). For LPP, the best predictive correlation was also obtained with CNN (0.29), followed by LCNN (0.27) and conventional linear models (approximately 0.25). A similar trend was observed with the mean squared error of prediction for the SLP traits., Conclusion: This study provides an example of a CNN that can outperform against the linear model-based genomic prediction approaches when the nonlinear interaction components are important because LNL and LPP exhibited strong epistatic interaction components. Additionally, our results suggest that applying bivariate DL models could also contribute to the prediction accuracy by utilizing the genetic correlation between LNL and LPP.

Objective: Beef of Jeju black cattle (JBC) is considered as a healthy meat type due to its significantly higher unsaturated fatty acids (UFA). Lipid (e.g., UFA) is highly susceptible to oxidizing agents, which results in the quality deterioration and economic value loss of meat products. Therefore, development and application of novel preservative techniques is necessary to improve the shelf-life stability of high-UFA beef. The objective of this study was to assess the applicability of chitosan-based coatings in preservation of JBC beef., Methods: Different coating solutions: 2% chitosan alone, and 2% chitosan containing 0.1% or 0.3% gallic acid were prepared to investigate their applicability in preservation of fresh beef during storage. Jeju black cattle beef (2-cm thick steaks) were non-coated (control) or coated with the above coating solutions, placed on trays, over-wrapped with plastic film and stored at 4°C. The microbiological indices, color, total volatile basic nitrogen (TVBN) and lipid oxidation of the beef were investigated after 1, 10, and 21 days of storage., Results: Coating with 2% chitosan alone reduced the spoilage bacteria count, TVBN and thiobarbituric acid reactive substances levels in the beef compared with control during storage (p<0.05). Noticeably, coating with 2% chitosan containing 0.1% or 0.3% gallic acid was more effective on retardation of spoilage bacteria growth, lipid oxidation and discoloration in the beef compared to the chitosan coating alone over the storage period (21 days) (p<0.05)., Conclusion: Taken together, the combined chitosan and gallic acid coating could be used as a bio-preservative technique in the meat industry.

Objective: The objective of this study was to evaluate the effect of biogas slurry application on biomass production and the silage quality of corn., Methods: A field experiment was conducted in which corn was grown using different biogas slurry application rates. The effect of 25% to 500% biogas slurry nitrogen replacement (T1 to T14) on the yield and quality indices of corn were studied by field plot experiments., Results: The results revealed that biogas slurry application improved the stem diameter and relative feed value of corn silage in treatments T13 and T11. Moreover, the fermentation quality of corn silage was improved due to an increase in lactic acid content; in comparison with the chemical synthetic fertilizer (CF) group. The crude protein contents of corn silage had no obvious change with increasing biogas slurry application. However, the forage quality index of acid detergent fiber was decreased (p<0.05) in the T11 group compared with the CF group. In addition, higher (p<0.05) 30 h in vitro dry matter digestibility and 30 h in vitro neutral detergent fiber digestibility were observed in the T11 and T13 groups than in the CF group., Conclusion: Based on these results, it was concluded that the optimum biogas slurry application rate for corn was approximately 350% to 450% biogas slurry nitrogen replacement under the present experimental conditions.

Objective: This study aimed to identify the single-nucleotide polymorphisms (SNPs) in the dual-specificity phosphatase 8 (DUSP8) and insulin-like growth factor 2 (IGF2) genes and to explore their effects on inosine-5'-monophosphate (IMP), inosine, and hypoxanthine contents in Korean native chicken -red-brown line (KNC-R Line)., Methods: A total sample of 284 (males, n = 127; females n = 157) and 230 (males, n = 106; females, n = 124) aged of 10 weeks old KNC-R line was used for genotyping of DUSP8 and IGF2 genes, respectively. One SNP (rs313443014 C>T) in DUSP8 gene and two SNPs (rs315806609A/G and rs313810945T/C) in IGF2 gene were used for genotyping by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and KASP methods, respectively. The Two-way analysis of variance of the R program was used to associate DUSP8 and IGF2 genotypes with nucleotide contents in KNC-R chickens., Results: The DUSP8 (rs313443014 C>T) was polymorphic in KNC-R line and showed three genotypes: CC, CT, and TT. The IGF2 gene (rs315806609A/G and rs313810945T/C) was also polymorphic and had three genotypes per SNP, including GG, AG, and AA for the SNP rs315806609A/G and genotypes: CC, CT, and TT for the SNP rs313810945T/C. Association resulted into a strong significant association (p<0.01) with IMP, inosine, and hypoxanthine. Moreover, the significant effect of sex (p<0.05) on nucleotide content was also observed., Conclusion: The SNPs in the DUSP8 and IGF2 genes might be used as genetic markers in the selection and production of chickens with highly flavored meat.

Objective: The purpose of this study was to perform a comparative analysis of metabolite levels in serum and milk obtained from cows fed on different concentrate to forage feed ratios., Methods: Eight lactating Holstein cows were divided into two groups: a high forage ratio diet (HF; 80% Italian ryegrass and 20% concentrate of daily intake of dry matter) group and a high concentrate diet (HC; 20% Italian ryegrass and 80% concentrate) group. Blood was collected from the jugular vein, and milk was sampled using a milking machine. Metabolite levels in serum and milk were estimated using proton nuclear magnetic resonance and subjected to qualitative and quantitative analyses performed using Chenomx 8.4. For statistical analysis, Student's t-test and multivariate analysis were performed using Metaboanalyst 4.0., Results: In the principal component analysis, a clear distinction between the two groups regarding milk metabolites while serum metabolites were shown in similar. In serum, 95 metabolites were identified, and 13 metabolites (include leucine, lactulose, glucose, betaine, etc.) showed significant differences between the two groups. In milk, 122 metabolites were identified, and 20 metabolites (include urea, carnitine, acetate, butyrate, arabinitol, etc.) showed significant differences., Conclusion: Our results show that different concentrate to forage feed ratios impact the metabolite levels in the serum and milk of lactating Holstein cows. A higher number of metabolites in milk, including those associated with milk fat synthesis and the presence of Escherichia coli in the rumen, differed between the two groups compared to that in the serum. The results of this study provide a useful insight into the metabolites associated with different concentrate to forge feed ratios in cows and may aid in the search for potential biomarkers for subacute ruminal acidosis.

Objective: This study determined the effects of dietary treatments and castration on meat quality, fatty acids (FAs) profiles, and volatile compounds in Korean native black goats (KNBG, Capra hircus coreanae), including the relationship between the population of rumen microbiomes and meat FA profiles., Methods: Twenty-four KNBG (48.6±1.4 kg) were randomly allocated to one of four treatments arranged into a 2×2 factorial structure. The factors were dietary forage to concentrate ratio (high forage [HF, 80:20] and low forage [LF, 20:80]), and a castration treatment (castration [CA] vs non-castration [NCA])., Results: Among meat quality traits, the CA group exhibited a higher percentage of crude fat and water holding capacity (p<0.05). The profiles of the saturated fatty acid (SFA) in meat sample derived from CA KNBG showed a significantly lower percentage compared to NCA individuals, due to the lower proportion of C14:0 and C18:0. Feeding a high-forage diet to KNBG increased the formation of C18:1n7, C18:3n3, C20:1n9, C22:4n6 in meat, and polyunsaturated fatty acid (PUFA) profiles (p<0.05). Consequently, the n6:n3 ratio declined (p<0.05). There was an interaction between dietary treatment and castration for formation of C20:5n3 (p<0.05), while C18:1n9, C22:6n3, monounsaturated fatty acid (MUFA) and the MUFA:SFA ratio were influenced by both diet and castration (p<0.05). Nine volatile compounds were identified and were strongly influenced by both dietary treatments, castration (p<0.05), and their interaction. In addition, principal component analysis (PCA) revealed distinctly different odor patterns in the NCA goats fed LF diets. Spearman correlation analysis showed a high correlation between rumen bacteria and meat PUFAs., Conclusion: These results suggest the essential effects of the rumen microbial population for the synthesis of meat FAs and volatile compounds in KNBG meat, where dietary intake and castration also contribute substantially.

Objective: For decades, LYD ([Landrace×Yorkshire] ♀×Duroc ♂) pigs are the most commonly-used commercial breed for meat production in Korea. Recently, due to the increasing demand for premium pork, the National Institute of Animal Science (Korea) has synthesized a novel pig breed named Woori Heukdon (WHD). This study aimed at comparing the carcass traits, meat yield and quality characteristics between the LYD and WHD pigs under identical rearing condition., Methods: The WHD and LYD pigs (n = 15 each) were reared under identical conditions and fed the same commercial diet until reaching recommended market weight (100 to 120 kg). After slaughter, the carcasses were evaluated for traits and meat yield, and the meat quality was assessed on shoulder butt and belly cuts., Results: Although no significant differences (p>0.05) occurred in slaughter weight between two pig types, WHD had a lower meat yield (by about 6 kg corresponding to approximately 7%) compared to the LYD pigs (p<0.05). The WHD had a higher fat content (by 4.26% and 13.52% in the shoulder butt and belly, respectively) compared to those of LYD pigs (p<0.05). The WHD meat showed a lower cooking loss and higher a* (redness) value (p<0.05). The WHD belly had a significantly (p<0.05) higher oleic acid content and concentrations of nonanal, octanal and decanal associated with fatty odor while, the LYD meat had a higher number of pyrazines associated with roasty odor. Regarding sensory quality, higher flavor, juiciness, and acceptability higher scores were given for the WHD meat than for the LYD meat (p<0.05)., Conclusion: Under identical rearing conditions the WHD exhibited a better meat quality and sensory properties. However, the use of this diet resulted in a high fat level that may be associated with high trimming loss for the WHD.

Objective: The better understanding of laying pattern of birds is crucial for developing breed-specific proper breeding scheme and management., Methods: Daily egg production until 50 wk of age of six chicken breeds including one layer (White Leghorn, WL), three dual-purpose (Rhode Island Red, RIR; Columbian Plymouth Rock, CR; and Barred Plymouth Rock, BR), one synthetic dwarf (DY), and one indigenous (Beijing-You Chicken, BYC) were used to characterize their clutch traits and egg production. The age at first egg, egg number, average and maximum clutch length, pause length, and number of clutches and pauses were calculated accordingly., Results: The egg number and average clutch length in WL, RIR, CR, and BR were higher than those in DY and BYC (p<0.01). The numbers of clutches and pauses, and pause length in WL, RIR, CR, and BR were lower than those in DY and BYC (p<0.01). The coefficient variations of clutch length in WL, RIR, CR, and BR (57.66%, 66.49%, 64.22%, and 55.35%, respectively) were higher than DY (41.84%) and BYC (36.29%), while the coefficient variations of egg number in WL, RIR, CR, and BR (9.10%, 9.97%, 10.82%, and 9.92%) were lower than DY (15.84%) and BYC (16.85%). The clutch length was positively correlated with egg number (r = 0.51 to 0.66; p<0.01), but not correlated with age at first egg in all breeds., Conclusion: The six breeds showed significant different clutch and egg production traits. Due to the selection history, the high and median productive layer breeds had higher clutch length than those of the less productive indigenous BYC. The clutch length is a proper selection criterion for further progress in egg production. The age at first egg, which is independent of clutch traits, is especially encouraged to be improved by selection in the BYC breed.

Objective: This study investigated the effects of corn silage as a source of microbial inoculant containing antifungal and carboxylesterase-producing bacteria on fermentation, aerobic stability, and nutrient digestibility of fermented total mixed ration (FTMR) with different energy levels., Methods: Corn silage was used as a bacterial source by ensiling for 72 d with an inoculant mixture of Lactobacillus brevis 5M2 and L. buchneri 6M1 at a 1:1 ratio. The corn silage without or with inoculant (CON vs MIX) was mixed with the other ingredients to formulate for low and high energy diets (LOW vs HIGH) for Hanwoo steers. All diets were ensiled into 20 L mini silo (5 kg) for 40 d in quadruplicate., Results: The MIX diets had lower (p<0.05) acid detergent fiber with higher (p<0.05) in vitro digestibilities of dry matter and neutral detergent fiber compared to the CON diets. In terms of fermentation characteristics, the MIX diets had higher (p<0.05) acetate than the CON diets. The MIX diets had extended (p<0.05) lactic acid bacteria growth at 4 to 7 d of aerobic exposure and showed lower (p<0.05) yeast growth at 7 d of aerobic exposure than the CON diets. In terms of rumen fermentation, the MIX diets had higher (p<0.05) total fermentable fraction and total volatile fatty acid, with lower (p<0.05) pH than those of CON diets. The interaction (p = 0.036) between inoculant and diet level was only found in the immediately fermentable fraction, which inoculant was only effective on LOW diets., Conclusion: Application of corn silage with inoculant on FTMR presented an antifungal effect by inhibiting yeast at aerobic exposure and a carboxylesterase effect by improving nutrient digestibility. It also indicated that fermented feedstuffs could be used as microbial source for FTMR. Generally, the interaction between inoculant and diet level had less effect on this FTMR study.

Objective: This study was conducted to investigate the effects of energy and protein levels in the diet of Hanwoo heifers on growth response and animal behavior., Methods: Forty heifers were randomly allocated into three experimental groups according to the target daily weight gain in 8 pens (T-0.2, 2 replications; T-0.4 and -0.6, 3 replications) based on similar body weight (BW) and age in months. The target average daily gain (ADG) was set at 0.2 (T-0.2), 0.4 (T-0.4), and 0.6 kg/d (T-0.6), and feed was based on National Institute of Animal Science (NIAS, 2017). In order to minimize hunger stress of T-0.2 and -0.4, the feeding ratio of rice straw was set to 55%, 50%, and 45% for T-0.2, -0.4 and T-0.6, respectively, so that the dry matter (DM) intake for all treatment groups was uniform but the energy and protein levels in the diet were adjusted differently. A total of 6 items (lying, standing, eating, rumination, walking and drinking) of animal behavior were analyzed., Results: During the whole period of the experiment, the ADG of the T-0.2, -0.4 and -0.6 treatments were 0.48, 0.56, and 0.65 kg/d (p<0.05), respectively, showing higher gain than the predicted value, especially for the low target ADG group. Based on these results, regression equations for the total digestible nutrient (TDN) and crude protein (CP) requirements were derived. No behavioral differences were found according to the energy and protein levels in the diet because the DM intake was kept constant by adjusting the roughage and concentration ratio. However, eating time was longer (p<0.05) at T-0.2 than T-0.6 during the whole day., Conclusion: Through this study, it was possible to derive regression equations for predicting TDN and CP requirements according to the target ADG and BW.

Objective: We aimed to evaluate the efficacy of a modified Double-Ovsynch protocol vs artificial insemination following estrus detection (AIED) for the enhancement of reproductive performance in Hanwoo cattle., Methods: Four hundred twelve Hanwoo cows were allocated to two treatment groups. The first group of cows were administered gonadotropin releasing hormone (GnRH) on Day 36 (±0.6), prostaglandin F2α (PGF2α) on Day 46 (8 to 12 days later), and GnRH on Day 49, which was followed by Ovsynch, consisting of an injection of GnRH on Day 56, PGF2α on Day 63, and GnRH 56 h and timed AI (TAI) 16 h later (modified Double-Ovsynch group, n = 203). The second group of cows underwent AIED (AIED group, n = 209) and were designated as controls., Results: The pregnancy per AI 60 days after the first AI was higher in the modified Double- Ovsynch (68.5%) than in the AIED (56.5%) group, resulting in a higher probability of pregnancy per AI (odds ratio: 1.68, p<0.05). Moreover, cows in the modified Double- Ovsynch group were more likely (hazard ratio: 1.28, p<0.05) to be pregnant by 150 days after calving than cows in the AIED group, and this difference was associated with a lower mean number of AIs per conception (1.27 vs 1.39, p<0.05) and a shorter median interval between calving and pregnancy (72 vs 78 days, p<0.1)., Conclusion: The modified Double-Ovsynch protocol, adjusted according to the herd visit schedule, can be readily used to increase the pregnancy per AI following the first AI and to shorten the interval between calving and pregnancy in beef herds.

Objective: Recently, indigenous Korean grass Sasa quelpaertensis Nakai (SQ) has garnered much interest as a roughage source for livestock to mitigate its adverse effects on habitat diversity. Thus, the objective of the present study was to evaluate the ruminal fermentation, palatability, and nutrient digestibility of SQ for Korean native beef cattle (Hanwoo) using in vitro rumen fermentation, in situ rumen degradability, and in vivo feeding trials., Methods: Using in vitro tests with rumen fluid as the inoculum for 48 h, ruminal fermentation of SQ was evaluated and compared with that of other roughage sources commonly used in Korea (i.e., rice straw, Timothy hay, and Italian ryegrass [IRG]). Additionally, an in situ trial 96 h was performed using three cannulated Hanwoo steers. Further, an in vivo trial was performed using eight Hanwoo steers to compare the palatability of SQ with rice straw in total mixed ration (TMR) and forage-concentrate separate feeding conditions. Finally, an in vivo digestibility trial of SQ fed as TMR of two particle sizes was performed with four Hanwoo steers., Results: In vitro and in situ trials revealed that SQ was comparable or superior to rice straw in terms of the ruminal fermentation characteristics of pH, gas production, total volatile fatty acid content, and effective ruminal dry matter digestibility (DMD), although its fermentability was lower than that of Timothy hay and IRG. In the palatability test, steers showed a greater preference for SQ when given as TMR. The total tract DMD of SQ fed as TMR was 75.9%±1.37%, and it did not differ by particle size., Conclusion: The feed value of SQ as a roughage source for Hanwoo steers is comparable or superior to that of rice straw, particularly when provided as TMR.

Objective: In this study, metabolites that changed in the rumen fluid, urine and feces of dairy cows fed different feed ratios were investigated., Methods: Eight Holstein cows were used in this study. Rumen fluid, urine, and feces were collected from the normal concentrate diet (NCD) (Italian ryegrass 80%: concentrate 20% in the total feed) and high concentrate diet (HCD) groups (20%: 80%) of dairy cows. Metabolite analysis was performed using proton nuclear magnetic resonance (NMR) identification, and statistical analysis was performed using Chenomx NMR software 8.4 and Metaboanalyst 4.0., Results: The two groups of rumen fluid and urine samples were separated, and samples from the same group were aggregated together. On the other hand, the feces samples were not separated and showed similar tendencies between the two groups. In total, 160, 177, and 188 metabolites were identified in the rumen fluid, urine, and feces, respectively. The differential metabolites with low and high concentrations were 15 and 49, 14 and 16, and 2 and 2 in the rumen fluid, urine, and feces samples, in the NCD group., Conclusion: As HCD is related to rumen microbial changes, research on different metabolites such as glucuronate, acetylsalicylate, histidine, and O-Acetylcarnitine, which are related to bacterial degradation and metabolism, will need to be carried out in future studies along with microbial analysis. In urine, the identified metabolites, such as gallate, syringate, and vanillate can provide insight into microbial, metabolic, and feed parameters that cause changes depending on the feed rate. Additionally, it is thought that they can be used as potential biomarkers for further research on subacute ruminal acidosis.

Objective: In this study, we aimed to position the Hungarian Merino among other Merino-derived sheep breeds, explore the characteristics of our sampled animals' genetic similarity network within the breed, and highlight single nucleotide polymorphisms (SNPs) associated with daily weight-gain., Methods: Hungarian Merino (n = 138) was genotyped on Ovine SNP50 Bead Chip (Illumina, San Diego, CA, USA) and positioned among 30 Merino and Merino-derived breeds (n = 555). Population characteristics were obtained via PLINK, SVS, Admixture, and Treemix software, within-breed network was analysed with python networkx 2.3 library. Daily weight gain of Hungarian Merino was standardised to 60 days and was collected from the database of the Association of Hungarian Sheep and Goat Breeders. For the identification of loci associated with daily weight gain, a multi-locus mixed-model was used., Results: Supporting the breed's written history, the closest breeds to Hungarian Merino were Estremadura and Rambouillet (pairwise FST values are 0.035 and 0.036, respectively). Among Hungarian Merino, a highly centralised connectedness has been revealed by network analysis of pairwise values of identity-by-state, where the animal in the central node had a betweenness centrality value equal to 0.936. Probing of daily weight gain against the SNP data of Hungarian Merinos revealed five associated loci. Two of them, OAR8&#95;17854216.1 and s42441.1 on chromosome 8 and 9 (-log10P>22, false discovery rate<5.5e-20) and one locus on chromosome 20, s28948.1 (-log10P = 13.46, false discovery rate = 4.1e-11), were close to the markers reported in other breeds concerning daily weight gain, six-month weight, and post-weaning gain., Conclusion: The position of Hungarian Merino among other Merino breeds has been determined. We have described the similarity network of the individuals to be applied in breeding practices and highlighted several markers useful for elevating the daily weight gain of Hungarian Merino.

Objective: This study examined the effects of dietary calcium (Ca) and non-phytate phosphorus (NPP) on performance, tibial characteristics, meat quality and plasma biochemical variables in yellow-feathered broilers during 85 to 105 d of age., Methods: A total of 720 heads of 85-d broilers were allocated into 9 groups and provided with three levels of Ca (0.65%, 0.75%, 0.85%), and NPP (0.25%, 0.30%, 0.35%) in diets for 21 d., Results: The final body weight (FW), average daily gain (ADG), average daily feed intake (ADFI), and feed to gain ratio (F:G) were affected (p<0.05) by dietary Ca. From the quadratic regressions, the optimal level of Ca in diet were 0.71% for FW and ADG, and 0.67% for ADFI. Dietary Ca and NPP both significantly affected tibial breaking strength and density. From the quadratic regressions, the optimal level of Ca and NPP in diet were 0.81% and 0.37% for tibial density. The shear force of breast muscle of broilers given 0.75% or 0.85% Ca were lower than that in birds with 0.65% Ca and drip loss of birds given 0.65% or 0.75% Ca was lower than that in birds with 0.85% Ca (p<0.05). The drip loss of birds given 0.25% NPP was lowest among all NPP treatments (p<0.05). Calcium affected (p<0.05) the plasmal contents of phosphorus, osteocalcin (OC), parathyroid hormone (PTH) and calcitonin and the contents of OC and PTH were also influenced by dietary NPP., Conclusion: Dietary Ca and NPP level affected tibial characteristics, meat quality and biochemical variables in plasma of finisher-phase yellow-feathered broilers (85 to 105 d) and Ca also affected growth performance. Dietary 0.71% Ca and 0.30% NPP were enough for growth performance, while considering the growth performance, tibial characteristics, meat quality and biochemical variables together, 0.75% Ca and 0.37% NPP were recommended.

Objective: This study aimed to evaluate the difference in the thigh meat quality of Ross 308 broiler from conventional and welfare farms., Methods: Thigh meat samples of Ross 308 broilers (age, 35 d; carcass weight, 1.1 kg) from conventional farm (RCF, n = 60) and animal welfare farms (RAWF, n = 60) were analyzed. Proximate composition, pH, color (lightness, redness, and yellowness), water-holding capacity (WHC), shear force, total aerobic bacteria (TAB), and volatile basic nitrogen (VBN) were measured and the levels of bioactive compounds such as dipeptides (anserine and carnosine), creatine, creatinine, and their anti-oxidation activity were determined., Results: The RCF and RAWF did not differ significantly in their proximate composition, WHC, color, and creatine and carnosine levels. The pH value was significantly lower in RAWF than in RCF on day 7. The shear force value was significantly higher in RAWF than in RCF throughout the storage duration. TAB in RCF on day 9 were significantly higher than those in RAWF. The VBN content of RAWF was significantly lower than that of RCF after 5 days of storage. Creatinine content was significantly higher in RAWF (3.50 mg/100 g) than in RCF (3.08 mg/100 g) on day 1. Along with higher carnosine and anserine contents of RAWF, it had significantly higher 2,2-diphenyl-1-picrylhydrazyl and 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) radical scavenging activities than those of RCF., Conclusion: These results imply that the animal welfare farming system beneficially affects the overall oxidative stability of Ross 308 thigh meat.

Objective: The study of Hanwoo (Korean native cattle) has mainly been focused on meat quality and productivity. Recently the field of microbiome research has increased dramatically. However, the information on the microbiome in Hanwoo is still insufficient, especially relationship between vagina and feces. Therefore, the purpose of this study is to examine the microbial community characteristics by analyzing the 16S rRNA sequencing data of Hanwoo vagina and feces, as well as to confirm the difference and correlation between vaginal and fecal microorganisms. As a result, the goal is to investigate if fecal microbiome can be used to predict vaginal microbiome., Methods: A total of 31 clinically healthy Hanwoo that delivered healthy calves more than once in Cheongju, South Korea were enrolled in this study. During the breeding season, we collected vaginal and fecal samples and sequenced the microbial 16S rRNA genes V3-V4 hypervariable regions from microbial DNA of samples., Results: The results revealed that the phylum-level microorganisms with the largest relative distribution were Firmicutes, Actinobacteria, Bacteroidetes, and Proteobacteria in the vagina, and Firmicutes, Bacteroidetes, and Spirochaetes in the feces, respectively. In the analysis of alpha, beta diversity, and effect size measurements (LefSe), the results showed significant differences between the vaginal and fecal samples. We also identified the function of these differentially abundant microorganisms by functional annotation analyses. But there is no significant correlation between vaginal and fecal microbiome., Conclusion: There is a significant difference between vaginal and fecal microbiome, but no significant correlation. Therefore, it is difficult to interrelate vaginal microbiome as fecal microbiome in Hanwoo. In a further study, it will be necessary to identify the genetic relationship of the entire microorganism between vagina and feces through the whole metagenome sequencing analysis and meta-transcriptome analysis to figure out their relationship.

Objective: Raw potato starch (RPS) is resistant to digestion, escapes absorption, and is metabolized by intestinal microflora in the large intestine and acts as their energy source. In this study, we compared the effect of different concentrations of RPS on the intestinal bacterial community of weaned piglets., Methods: Male weaned piglets (25-days-old, 7.03±0.49 kg) were either fed a corn/soybean-based control diet (CON, n = 6) or two treatment diets supplemented with 5% RPS (RPS5, n = 4) or 10% RPS (RPS10, n = 4) for 20 days and their fecal samples were collected. The day 0 and 20 samples were analyzed using a 16S rRNA gene sequencing technology, followed by total genomic DNA extraction, library construction, and high-throughput sequencing. After statistical analysis, five phyla and 45 genera accounting for over 0.5% of the reads in any of the three groups were further analyzed. Furthermore, short-chain fatty acids (SCFAs) in the day 20 fecal samples were analyzed using gas chromatography., Results: Significant changes were not observed in the bacterial composition at the phylum level even after 20 d post feeding (dpf); however, the abundance of Intestinimonas and Barnesiella decreased in both RPS treatment groups compared to the CON group. Consumption of 5% RPS increased the abundance of Roseburia (p<0.05) and decreased the abundance of Clostridium (p<0.01) and Mediterraneibacter (p< 0.05). In contrast, consumption of 10% RPS increased the abundance of Olsenella (p<0.05) and decreased the abundance of Campylobacter (p<0.05), Kineothrix (p<0.05), Paraprevotella (p<0.05), and Vallitalea (p<0.05). Additionally, acetate (p<0.01), butyrate (p<0.05), valerate (p = 0.01), and total SCFAs (p = 0.01) were upregulated in the RPS5 treatment group., Conclusion: Feeding 5% RPS altered bacterial community composition and promoted gut health in weaned piglets. Thus, resistant starch as a feed additive may prevent diarrhea in piglets during weaning.

Objective: Our study aimed to investigate the effects of a 2% increase in dietary total digestible nutrients (TDN) value during the growing (7 to 12 mo of age) and fattening (13 to 30 mo of age) period of Hanwoo steers., Methods: Two hundred and twenty Hanwoo steers were assigned to one of two treatments: i) a control group (basal TDN, BTDN, n = 111 steers, growing = 70.5%, early fattening = 71.0%, late fattening = 74.0%) or high TDN (HTDN, n = 109 steers, growing = 72.6%, early = 73.1%, late = 76.2%). Growth performance, carcass traits, blood parameters, and gene expression of longissimus dorsi (LD) (7, 18, and 30 mo) were quantified., Results: Steers on the BTDN diets had increased (p≤0.02) DMI throughout the feeding trial compared to HTDN, but gain did not differ appreciably. A greater proportion of cattle in HTDN received Korean quality grade 1 (82%) or greater compared to BTDN (77%), while HTDN had a greater yield grade (29%) than BTDN (20%). Redness (a*) of LD muscle was improved (p = 0.021) in steers fed HTDN. Feeding the HTDN diet did not alter blood parameters. Steers fed HTDN diet increased (p = 0.015) the proportion of stearic acid and tended to alter linoleic acid. Overall, saturated, unsaturated, monounsaturated, and polyunsaturated fatty acids of LD muscle were not impacted by the HTDN treatment. A treatment by age interaction was noted for mRNA expression of myosin heavy chain (MHC) IIA, IIX, and stearoyl CoA desaturase (SCD) (p≤0.026). No treatment effect was detected on gene expression from LD muscle biopsies at 7, 18, and 30 mo of age; however, an age effect was detected for all variables measured (p≤0.001)., Conclusion: Our results indicated that feeding HTDN diet could improve overall quality grade while minimum effects were noted in gene expression, blood parameters, and growing performance. Cattle performance prediction in the feedlot is a critical decisionmaking tool for optimal planning of cattle fattening and these data provide both benchmark physiological parameters and growth performance measures for Hanwoo cattle feeding enterprises.

Objective: Luxi Black Head sheep (LBH) is the first crossbreed specialized for meat production and was developed by crossbreeding Black Head Dorper sheep (DP) and Small Tailed Han sheep (STH) in the farming areas of northern China. Research on the genomic variations and selection signatures of LBH caused by continuous artificial selection is of great significance for identifying the genetic mechanisms of important traits of sheep and for the continuous breeding of LBH., Methods: We explored the genetic relationships of LBH, DP, and several Mongolian sheep breeds by constructing phylogenetic tree, principal component analysis and linkage disequilibrium analysis. In addition, we analysed 29 whole genomes of sheep. The genomewide selection signatures have been scanned with four methods heterozygosity (HP), fixation index (FST), cross-population extended haplotype homozygosity (XP-EHH) and the nucleotide diversity (θπ) ratio., Results: The genetic relationships analysis showed that LBH appeared to be an independent cluster closer to DP. The candidate signatures of positive selection in sheep genome revealed candidate genes for developmental process (HoxA gene cluster, BCL2L11, TSHR), immunity (CXCL6, CXCL1, SKAP2, PTK6, MST1R), growth (PDGFD, FGF18, SRF, SOCS2), and reproduction (BCAS3, TRIM24, ASTL, FNDC3A). Moreover, two signalling pathways closely related to reproduction, the thyroid hormone signalling pathway and the oxytocin signalling pathway, were detected., Conclusion: The selective sweep analysis of LBH genome revealed candidate genes and signalling pathways associated with developmental process, immunity, growth, and reproduction. Our findings provide a valuable resource for sheep breeding and insight into the mechanisms of artificial selection.

Objective: This study was designed to investigate the hypothesis that dietary quercetin (QUE) and coated sodium butyrate (SB) supplementation alleviate oxidative stress in the small intestine of diquat (DIQ)-challenged pullets., Methods: A total of 200 13-week-old pullets were divided into four groups: the control group (CON), the DIQ group, the QUE group, and the coated SB group, and injected intraperitoneally with either saline (CON) or diquat (DIQ, QUE, and SB) to induce oxidative stress on day 0., Results: On the first day, the malondialdehyde and superoxide dismutase (SOD) concentrations in the SB group were significantly different from those in the DIQ and QUE groups (p<0.05), and dietary supplementation with SB increased serum glutathione peroxidase (GSH-PX) levels compared with the DIQ group (p<0.05). Quercetin and SB increased the levels of CLAUDIN-1 and zonula occludens-1 (ZO-1) in the jejunum. On the tenth day of treatment, QUE attenuated the decrease in GSH-PX levels compared to those of the CON group (p<0.05), while SB increased SOD, GSH-PX, and total antioxidant capacity levels compared to those of the DIQ group. Nuclear factor erythroid 2-related factor 2 (NRF2) and heme oxygenase-1 (HO-1) mRNA levels in the QUE and SB groups increased (p<0.05) and CLAUDIN-1 mRNA levels in the QUE and SB groups were upregulated compared to those in the DIQ group ileum tissue., Conclusion: Supplementation of QUE and SB demonstrated the ability to relieve oxidative stress in pullets post DIQ-injection with a time-dependent manner and QUE and SB may be potential antioxidant additives for relieving oxidative stress and protecting the intestinal barrier of pullets.

Objective: The objective of this study was to determine whether dietary black soldier fly (Hermetia illucens, HI) larvae oil (HILO) could serve as an alternative fat source to soybean oil (SBO) in laying hen diets., Methods: We randomly assigned 25-week-old Hy-line Brown laying hens (n = 144) to receive (n = 6 hens/group; eight replicates) a control or an experimental diet in which SBO was replaced with 50% (50HILO) or 100% HILO (100HILO)., Results: Dietary HILO did not negatively affect body weight or productive performance during the study. The eggs also had similar quality parameters, proximate composition, and cholesterol levels. However, the yolk color index was significantly higher (p<0.01) in the 100HILO than in the other groups. Dietary HILO significantly altered the composition of fatty acids (FAs) in abdominal fat and eggs. Total saturated fatty acids (SFAs) and total polyunsaturated FAs (PUFAs) were significantly increased and decreased in the 50HILO and 100HILO groups, respectively, compared with those in the control group (p<0.001 and p<0.0001, respectively). Specifically, the medium-chain FAs lauric and myristic acids were remarkably increased in the abdominal fat of laying hens fed HILO (p<0.0001), whereas only myristic acid increased in eggs (p<0.0001). Undesirable heavy metal (aluminum, fluorine, arsenic, lead, mercury, and cadmium) concentrations were below permissible limits in eggs., Conclusion: We considered that HILO could be an alternative dietary fat to SBO for laying hens with maintained productive performance and good egg quality.

Objective: For improving meat quality especially tenderness, male cattle are usually castrated to removes both the testicles. This study was conducted to evaluate the effect castration method (half- and complete-castration) on meat yield and quality characteristics of Hanwoo male cattle., Methods: Thirty-two similar age (5.9 months) Hanwoo male calves were divided into: half-castration (HC) and complete-castration (CC) groups (n = 16 per group). At 7 months of age, all the animals were castrated in which the HC calves had only one testicle surgically removed while, the CC calves had both testicles surgically removed. The castrated animals were reared under identical conditions until 25 months of age. After slaughter, the carcasses were evaluated for carcass traits and meat yield of primal cuts. For examination of the castration effect on meat quality, L. lumborum and semimembranosus muscles were used. The meat samples were analyzed for chemical composition, color, pH, shear force and water holding capacity, fatty acids, metabolites and volatile aroma compounds., Results: The HC group showed higher meat yields of all primal cuts (p<0.05). As a result, the total meat yield was higher by approximately 44 kg in the HC group (303.32 kg, corresponding to 67.88%) compared to the CC group (259.30 kg, corresponding to 62.11%) (p<0.05). In terms of meat quality, the HC resulted in two times greater fat content in both muscles examined compared to intact males. More importantly, the shear force values did not differ between HC and CC groups for L. lumborum muscles (p>0.05). The meat from HC animals exhibited higher amount of free amino acids associated with sweetness (p<0.05). Furthermore, the castration method only exhibited a negligible effect on metabolites and volatile aroma compounds in the cooked meat., Conclusion: Half-castration emerged as an alternative practice to be used for increasing the yield and tenderness of male cattle meat.

Objective: This study was conducted to identify the functional long non-coding RNAs (lncRNAs) for swine lactation by RNA-seq data of mammary gland., Methods: According to the RNA-seq data of swine mammary gland, we screened lncRNAs, performed differential expression analysis, and confirmed the functional lncRNAs for swine lactation by validation of genome wide association study (GWAS) signals, functional annotation and weighted gene co-expression network analysis (WGCNA)., Results: We totally identified 286 differentially expressed (DE) lncRNAs in mammary gland at different stages from 14 days prior to (-) parturition to day 1 after (+) parturition, and the expressions of most of lncRNAs were strongly changed from day -2 to day +1. Further, the GWAS signals of sow milk ability trait were significantly enriched in DE lncRNAs. Functional annotation revealed that these DE lncRNAs were mainly involved in mammary gland and lactation developing, milk composition metabolism and colostrum function. By performing weighted WGCNA, we identified 7 out of 12 lncRNA-mRNA modules that were highly associated with the mammary gland at day -14, day -2, and day +1, in which, 35 lncRNAs and 319 mRNAs were involved., Conclusion: This study suggested that 18 lncRNAs and their 20 target genes were promising candidates for swine parturition and colostrum occurrence processes. Our research provided new insights into lncRNA profiles and their regulating mechanisms from colostrogenesis to lactogenesis in swine.

Objective: A formula is needed that is practical for current livestock breeding methods and that predicts the approximate rate of inbreeding (∆F) in populations where selection is performed according to four-path programs (sires to breed sons, sires to breed daughters, dams to breed sons, and dams to breed daughters). The formula widely used to predict inbreeding neglects selection, we need to develop a new formula that can be applied with or without selection., Methods: The core of the prediction is to incorporate the long-tern genetic influence of the selected parents in four-selection paths executed as sires to breed sons, sires to breed daughters, dams to breed sons, and dams to breed daughters. The rate of inbreeding was computed as the magnitude that is proportional to the sum of squared long-term genetic contributions of the parents of four-selection paths to the selected offspring., Results: We developed a formula to predict the rate of inbreeding in populations undergoing four-path selection on genomically enhanced breeding values and with discrete generations. The new formula can be applied with or without selection. Neglecting the effects of selection led to underestimation of the rate of inbreeding by 40% to 45%., Conclusion: The formula we developed here would be highly useful as a practical method for predicting the approximate rate of inbreeding (ΔF) in populations where selection is performed according to four-path programs.

Objective: A genomic region associated with a particular phenotype is called quantitative trait loci (QTL). To detect the optimal F2 population size associated with QTLs in native chicken, we performed a simulation study on F2 population derived from crosses between two different breeds., Methods: A total of 15 males and 150 females were randomly selected from the last generation of each F1 population which was composed of different breed to create two different F2 populations. The progenies produced from these selected individuals were simulated for six more generations. Their marker genotypes were simulated with a density of 50K at three different heritability levels for the traits such as 0.1, 0.3, and 0.5. Our study compared 100, 500, 1,000 reference population (RP) groups to each other with three different heritability levels. And a total of 35 QTLs were used, and their locations were randomly created., Results: With a RP size of 100, no QTL was detected to satisfy Bonferroni value at three different heritability levels. In a RP size of 500, two QTLs were detected when the heritability was 0.5. With a RP size of 1,000, 0.1 heritability was detected only one QTL, and 0.5 heritability detected five QTLs. To sum up, RP size and heritability play a key role in detecting QTLs in a QTL study. The larger RP size and greater heritability value, the higher the probability of detection of QTLs., Conclusion: Our study suggests that the use of a large RP and heritability can improve QTL detection in an F2 chicken population.

Objective: The objective was to test additivity of digestible energy and nutrient concentrations in the hatchery byproduct mixture fed to nursery pigs., Methods: In the previous studies, energy, phosphorus, calcium, and amino acid digestibility of infertile eggs, unhatched eggs, culled chicks, and a mixture of 3 hatchery byproduct ingredients was determined in nursery pigs (initial body weight = 9.4 to 14.2 kg). An additivity test was conducted using these determined values., Results: No difference was observed between determined and predicted metabolizable energy values in the mixture (3,998 and 3,990 kcal/kg as-is basis, respectively). Measured standardized total tract digestible phosphorus in the mixture was less than the predicted value (4.5 vs 5.3 g/kg as-is basis, respectively; p<0.05). Measured standardized total tract digestible calcium in the mixture was greater compared with the predicted value (40.0 vs 31.7 g/kg as-is basis, respectively; p<0.05). Measured standardized ileal digestible tryptophan in the mixture was greater than the predicted value (3.7 vs 3.1 g/kg as-is basis, respectively; p<0.05) whereas other amino acid values were additive., Conclusion: Energy and most of amino acid concentrations in hatchery byproducts are additive in the mixture fed to nursery pigs.

Objective: The highly pathogenic avian influenza virus (HPAIV) is a threat to the poultry industry as well as the economy and remains a potential source of pandemic infection in humans. Antiviral genes are considered a potential factor for HPAIV resistance. Therefore, in this study, we investigated gene expression related to cytokine-cytokine receptor interactions by comparing resistant and susceptible Ri chicken lines for avian influenza virus infection., Methods: Ri chickens of resistant (Mx/A; BF2/B21) and susceptible (Mx/G; BF2/B13) lines were selected by genotyping the Mx dynamin like GTPase (Mx) and major histocompatibility complex class I antigen BF2 genes. These chickens were then infected with influenza A virus subtype H5N1, and their lung tissues were collected for RNA sequencing., Results: In total, 972 differentially expressed genes (DEGs) were observed between resistant and susceptible Ri chickens, according to the gene ontology and Kyoto encyclopedia of genes and genomes pathways. In particular, DEGs associated with cytokine-cytokine receptor interactions were most abundant. The expression levels of cytokines (interleukin-1β [IL-1β], IL-6, IL-8, and IL-18), chemokines (C-C Motif chemokine ligand 4 [CCL4] and CCL17), interferons (IFN-γ), and IFN-stimulated genes (Mx1, CCL19, 2'-5'-oligoadenylate synthaselike, and protein kinase R) were higher in H5N1-resistant chickens than in H5N1-susceptible chickens., Conclusion: Resistant chickens show stronger immune responses and antiviral activity (cytokines, chemokines, and IFN-stimulated genes) than those of susceptible chickens against HPAIV infection.

Objective: The aim of the study was to evaluate the influence of gene polymorphisms and nongenetic factors on the somatic cell score (SCS) in the milk of Holstein (n = 148) and Simmental (n = 73) cows and their crosses (n = 6)., Methods: The SCS was calculated by the formula SCS = log2(SCC/100,000)+3, where SCC is the somatic cell count. Polymorphisms in the casein alpha S1 (CSN1S1), beta-casein (CSN2), kappa-casein (CSN3), beta-lactoglobulin (LGB), acyl-CoA diacylglycerol transferase 1 (DGAT1), leptin (LEP), fatty acid synthase (FASN), stearoyl CoA desaturase 1 (SCD1), and 1-acylglycerol-3-phosphate O-acyltransferase 6 (AGPAT6) genes were genotyped, and association analysis to the SCS in the cow's milk was performed. Further, the impact of breed, farm, year, month of the year, lactation stage and parity on the SCS were analysed. Phenotype correlations among SCS and milk constituents were computed by Pearson correlation coefficients., Results: Only CSN2 genotypes A1/A2 were found to have significant association with the SCS (p<0.05), and alleles of CSN1S1 and DGAT1 genes (p<0.05). Other polymorphisms were not found to be significant. SCS had significant association with the combined effect of farm and year, lactation stage and month of the year. Lactation parity and breed had not significant association with SCS. The phenotypic correlation of SCS to lactose content was negative and significant, while the correlation to protein content was positive and significant. The correlations of SCS to fat, casein, nonfat solids, urea, citric acid, acetone and ketones contents were very low and not significant., Conclusion: Only CSN2 genotypes, CSN1S1 and DGAT1 alleles did show an obvious association to the SCS. The results confirmed the importance of general quality management of farms on the microbial milk quality, and effects of lactation stage and month of the year. The lactose content in milk reflects the health status of the udder.

Objective: The aim of the study was to conduct metabolic profiling of dairy cattle serum and urine using proton nuclear magnetic resonance (1H-NMR) spectroscopy and to compare the results obtained with those of other dairy cattle herds worldwide so as to provide a basic dataset to facilitate research on metabolites in serum and urine., Methods: Six dairy cattle were used in this study; all animals were fed the same diet, which was composed of total mixed ration; the fed amounts were based on voluntary intake. Blood from the jugular neck vein of each steer was collected at the same time using a separate serum tube. Urine samples were collected by hand sweeping the perineum. The metabolites were determined by 1H-NMR spectroscopy, and the obtained data were statistically analyzed by performing principal component analysis, partial least squares-discriminant analysis, variable importance in projection scores, and metabolic pathway data using Metaboanalyst 4.0., Results: The total number of metabolites in the serum and urine was measured to be 115 and 193, respectively, of which 47 and 81, respectively were quantified. Lactate (classified as an organic acid) and urea (classified as an aliphatic acylic compound) exhibited the highest concentrations in serum and urine, respectively. Some metabolites that have been associated with diseases such as ketosis, bovine respiratory disease, and metritis, and metabolites associated with heat stress were also found in the serum and urine samples., Conclusion: The metabolites measured in the serum and urine could potentially be used to detect diseases and heat stress in dairy cattle. The results could also be useful for metabolomic research on the serum and urine of ruminants in Korea.

Objective: In most retail centers, primal pork cuts for sale are usually prepared into retail-ready slices and overwrapped with air-permeable plastic film. Also, meat of Korean native black pig (KNP) is reputed for its superior quality, however, its shelf life during retail display has not been studied. Thus, the objective of this study was to evaluate shelf life of prepackaged retail-ready KNP belly and shoulder butt slices during refrigerated display., Methods: Bellies and shoulder butt obtained at 24 h post-mortem from finishing KNP were used. Each belly or shoulder butt was manually cut into 1.5 cm-thick slices. The slices in each cut type were randomly taken and placed on white foam tray (2 slices/tray) overwrapped with polyvinyl chloride film. The retail-ready packages were then placed in a retail display cabinet at 4°C. Shelf life and sensory quality of the samples were evaluated on day 1, 3, 6, 9, 12, and 15 of display., Results: The shoulder butt reached the upper limit (20 mg/100 g) of volatile basic nitrogen for fresh meat after 9 days while, the belly remained within this limit throughout the display time (15 days). Both the cuts reached a thiobarbituric acid reactive substances level of above 0.5 mg malondialdehyde/kg after 9 days. The a* (redness) values remained unchanged during first 9 days in both cuts (p>0.05). After 9 days, off-flavor was not found in either cut, but higher off-flavor intensity was found in shoulder butt after 12 days. The shoulder butt was unacceptable for overall eating quality after 12 days while, belly still was acceptable after 12 days., Conclusion: The belly showed a longer shelf life compared to the shoulder butt, and a shelf life of 9 and 12 days is recommended for the prepackaged retail-ready KNP shoulder butt and belly slices, respectively.

Objective: An experiment was conducted to evaluate the effects of bamboo leaf extract (BLE) on the production performance, rumen fermentation parameters, and rumen bacterial communities of heat-stressed dairy cows., Methods: The experiment comprised a 14-day adaptation period and a 21-day experimental period and was conducted in a high-temperature and humidity environment (daily mean ambient temperature = 33.5°C±1.3°C; daily mean relative humidity = 64.9%±0.8%, daily mean temperature-humidity index = 86.2±0.4). Twelve Holstein dairy cows were randomly allocated into two groups. A total mixed ration supplemented with BLE at 0 (CON) and 1.3 g/kg dry matter (DM) were fed, respectively. Feed intake and milk yield were recorded daily. Milk samples were collected on 1, 11, and 21 d of the experimental period to analyze milk performance. Rumen fluid samples were collected on 21 d of the experimental period to analyze rumen fermentation parameters and rumen bacterial communities., Results: Compared with the control group, supplementation of BLE increased milk yield (p<0.01), milk fat yield (p = 0.04), 4% fat-corrected milk (p<0.01) and milk fat content (p<0.01); reduced somatic cell count (p<0.01). No differences in DM intake and milk protein or lactose content were observed between two groups. Supplementation of BLE also increased the rumen total volatile fatty acid (p<0.01), acetate (p<0.01), butyrate (p<0.01), and valerate (p = 0.05) concentrations. However, no significant effects were observed on rumen pH, ammonia nitrogen, propionate, acetate/propionate ratio, isobutyrate, or isovalerate. Furthermore, BLE increased the rumen bacterial abundance and the diversity of the rumen bacterial community. The BLE reduced the Firmicutes/Bacteroidetes abundance ratio and increased the abundances of Butyrivibrio&#95;2 (p<0.01) and Ruminococcus&#95;2 (p<0.01)., Conclusion: The BLE supplementation at 1.3 g/kg DM could improve production performance and rumen fermentation in dairy cows during heat stress.

Objective: The objectives of the present study were to determine digestible energy (DE), metabolizable energy (ME), and standardized total tract digestibility (STTD) of phosphorus (P) in meat meal (MM) and to compare these values with those in fish meal (FM), and soybean meal (SBM) fed to pigs., Methods: Two experiments were conducted to determine energy concentrations and STTD of P in MM, FM, and SBM fed to growing pigs. In Exp. 1, DE and ME in the 3 test ingredients were measured using 24 barrows with initial body weight (BW) of 77.7±8.3 kg. A corn-based diet and 3 diets containing corn and 22% to 30% of each test ingredient were prepared. In Exp. 2, the STTD of P in the 3 test ingredients was measured using 24 barrows (90.9±6.6 kg BW). Three diets were formulated to contain each test ingredient as the sole source of P., Results: In Exp. 1, the DE and ME values in MM (3,310 and 2,856 kcal/kg dry matter [DM]) were less (p<0.05) than those in FM (4,121 and 3,572 kcal/kg DM) and SBM (4,390 and 4,032 kcal/kg DM). In Exp. 2, FM (64.3%) had greater (p<0.05) STTD of P than SBM (44.8%) with MM (55.8%) having intermediate STTD of P., Conclusion: The MM contains less energy concentrations compared with FM and SBM, and digestibility of phosphorus in MM does not differ from that in FM and SBM.

Objective: Pork belly is considered as the most commercially important and preferable primal cut by consumers worldwide. Thus, this study was conducted to determine the effects of fat levels on the meat quality characteristics of pork bellies., Methods: Seventy-eight growing-finishing pigs collected from different commercial pig farms were slaughtered and used in the present study. After slaughter 24 h, bellies were fabricated according to the Korean Pork Cutting Specification, and immediately sampled for analysis of their fat content. Based on the fat levels, the bellies were segregated into three different groups: low fat (LF, fat ≤20%, n = 15), medium fat (MF, fat 21% to 30%, n = 30), and high fat (HF, fat ≥31%, n = 33). The bellies were then analyzed for meat quality traits, fatty acids, flavor compounds and eating quality properties., Results: The HF group had lower moisture and cooking loss levels compared to the other groups (p<0.05). The LF group presented higher proportions of polyunsaturated fatty acids compared to the other groups (p<0.05). The LF group showed higher amounts of the Maillard reaction-derived flavor compounds (e.g., 2,5-dimethyl pyrazine, 2-ethyl-3,5-dimethyl, and 4-methylthiazole) associated with meaty and roasty flavors whereas, the HF group showed higher amounts of oleic acid- derived compounds (e.g., nonanal and octanal) associated with the fatty and oily flavors. Interestingly, significantly higher scores for all the eating quality attributes (flavor, juiciness, tenderness, and overall acceptance) were found in the HF group compared to those in the LF or MF group (p<0.05)., Conclusion: The high-fat bellies (fat ≥31%) had a better technological quality and eating quality compared to the low-fat bellies (fat ≤20%). Thus, increasing the fat content may improve the technological quality and eating quality traits of pork bellies, however, this increase may also result in more trimmed loss due to excessively deposited body fat.

Objective: This study aimed to validate and evaluate the dry matter (DM) intake prediction model of the Korean feeding standards for dairy cattle (KFSD)., Methods: The KFSD DM intake (DMI) model was developed using a database containing the data from the Journal of Dairy Science from 2006 to 2011 (1,065 observations 287 studies). The development (458 observations from 103 studies) and evaluation databases (168 observations from 74 studies) were constructed from the database. The body weight (kg; BW), metabolic BW (BW0.75, MBW), 4% fat-corrected milk (FCM), forage as a percentage of dietary DM, and the dietary content of nutrients (% DM) were chosen as possible explanatory variables. A random coefficient model with the study as a random variable and a linear model without the random effect was used to select model variables and estimate parameters, respectively, during the model development. The best-fit equation was compared to published equations, and sensitivity analysis of the prediction equation was conducted. The KFSD model was also evaluated using in vivo feeding trial data., Results: The KFSD DMI equation is 4.103 (±2.994)+0.112 (±0.022)×MBW+0.284 (±0.020) ×FCM-0.119 (±0.028)×neutral detergent fiber (NDF), explaining 47% of the variation in the evaluation dataset with no mean nor slope bias (p>0.05). The root mean square prediction error was 2.70 kg/d, best among the tested equations. The sensitivity analysis showed that the model is the most sensitive to FCM, followed by MBW and NDF. With the in vivo data, the KFSD equation showed slightly higher precision (R2 = 0.39) than the NRC equation (R2 = 0.37), with a mean bias of 1.19 kg and no slope bias (p>0.05)., Conclusion: The KFSD DMI model is suitable for predicting the DMI of lactating dairy cows in practical situations in Korea.