Study on the fatty acid profile of phospholipid and neutral lipid in Hanwoo beef and their relationship to genetic variation

Maize which has very high omega-6 fatty acid content has been used as a main feed grain for Hanwoo beef production to increase marbling, and thus omega-6 to omega-3 fatty acids ratio in Hanwoo beef is expected to be biased. To elucidate the current status of omega fatty acids ratio in Hanwoo beef, fatty acid profiles of neutral lipid and phospholipid fraction were analyzed separately using 55 Hanwoo steers’ longissimus dorsi muscle slaughtered at Pyeongchang, Korea from Oct. to Nov. 2015. In addition, an association study was conducted to evaluate associations between single nucleotide polymorphism (SNP) markers from references and omega fatty acid profiles in phospholipid of Hanwoo beef samples using analysis of variance (ANOVA). In neutral lipid fraction, composition of saturated and monounsaturated fatty acids was higher and polyunsaturated fatty acids was lower compared to those in phospholipid fraction. The mean n-6/n-3 ratios of Hanwoo were 56.059 ± 16.180 and 26.811 ± 6.668 in phospholipid and neutral lipid, respectively. There were three SNPs showing statistically significant associations with omega fatty acid content. GA type of rs41919985 in fatty acid synthase (FASN) was significantly associated with the highest amount of C20:5 n-3 (p = 0.031). CC type of rs41729173 in fatty acid-binding protein 4 (FABP4) was significantly associated with the lowest amount of C22:2n-6 (p = 0.047). AG type of rs42187261 in FADS1 was significantly linked to the lowest concentration of C20:4 n-6 (p = 0.044). The total n-6/n-3 ratio of the steer which has all four SNP types in above loci (27.905) was much lower than the mean value of the total n-6/n-3 ratio in phospholipid of the 55 Hanwoo steers (56.059 ± 16.180). It was found that phospholipid and neutral lipid of Hanwoo have very high n-6/n-3 ratios compared to the reported data from different cow breeds. Four SNPs in genes related with fatty acid metabolism showed significant associations with the fatty acid profile of phospholipid and may have potential as SNP markers to select Hanwoo steers in terms of n-6/n-3 balance in the future

Genetic, management, and nutritional factors affecting intramuscular fat deposition in beef cattle — A review

Intramuscular fat (IMF) content in skeletal muscle including the longissimus dorsi muscle (LM), also known as marbling fat, is one of the most important factors determining beef quality in several countries including Korea, Japan, Australia, and the United States. Genetics and breed, management, and nutrition affect IMF deposition. Japanese Black cattle breed has the highest IMF content in the world, and Korean cattle (also called Hanwoo) the second highest. Here, we review results of research on genetic factors (breed and sex differences and heritability) that affect IMF deposition. Cattle management factors are also important for IMF deposition. Castration of bulls increases IMF deposition in most cattle breeds. The effects of several management factors, including weaning age, castration, slaughter weight and age, and environmental conditions on IMF deposition are also reviewed. Nutritional factors, including fat metabolism, digestion and absorption of feed, glucose/starch availability, and vitamin A, D, and C levels are important for IMF deposition. Manipulating IMF deposition through developmental programming via metabolic imprinting is a recently proposed nutritional method to change potential IMF deposition during the fetal and neonatal periods in rodents and domestic animals. Application of fetal nutritional programming to increase IMF deposition of progeny in later life is reviewed. The coordination of several factors affects IMF deposition. Thus, a combination of several strategies may be needed to manipulate IMF deposition, depending on the consumer’s beef preference. In particular, stage-specific feeding programs with concentrate-based diets developed by Japan and Korea are described in this article

Comparison of transcriptome between high- and low-marbling fineness in longissimus thoracis muscle of Korean cattle

Objective: This study compared differentially expressed genes (DEGs) between groups with high and low numbers of fine marbling particles (NFMP) in the longissimus thoracis muscle (LT) of Korean cattle to understand the molecular events associated with fine marbling particle formation. Methods: The size and distribution of marbling particles in the LT were assessed with a computer image analysis method. Based on the NFMP, 10 LT samples were selected and assigned to either high-(n = 5) or low-(n = 5) NFMP groups. Using RNA sequencing, LT transcriptomic profiles were compared between the high-and low-NFMP groups. DEGs were selected at p<0.05 and |fold change| >2 and subjected to functional annotation. Results: In total, 328 DEGs were identified, with 207 up-regulated and 121 down-regulated genes in the high-NFMP group. Pathway analysis of these DEGs revealed five significant (p<0.05) Kyoto encyclopedia of genes and genomes pathways; the significant terms included endocytosis (p = 0.023), protein processing in endoplasmic reticulum (p = 0.019), and adipocytokine signaling pathway (p = 0.024), which are thought to regulate adipocyte hypertrophy and hyperplasia. The expression of sirtuin4 (p<0.001) and insulin receptor substrate 2 (p = 0.043), which are associated with glucose uptake and adipocyte differentiation, was higher in the high-NFMP group than in the low-NFMP group. Conclusion: Transcriptome differences between the high-and low-NFMP groups suggest that pathways regulating adipocyte hyperplasia and hypertrophy are involved in the marbling fineness of the LT.Y

Comparison of reducing sugar content, sensory traits, and fatty acids and volatile compound profiles of the among Korean cattle, Holsteins, and Angus steers

Objective This study was performed to compare fat content, reducing sugar contents, sensory traits, and fatty acid (FA) and volatile compound profiles in longissimus thoracis (LT) among Korean cattle (KC), Holstein (HO), and Angus (AN) steers. Methods Twelve LT samples (about 500 g each) of KC with an average age of 31±0.42 months, an average carcass weight of 431±12.5 kg, and a quality grade (QG) of 1+ were obtained from the joint livestock products market. Twelve LT samples of HO cattle with an average age of 24±0.54 months, an average carcass weight of 402±7.81 kg, and a QG of 2 were also obtained from the same market. Twelve LT samples of AN steers with an average age of about 20 months and a QG of choice were purchased from a beef delivery company. After slaughter, samples were kept at 4°C for 42 days and prepared for immediate analysis or stored at appropriate conditions. The chemical composition, color, pH, shear force, collagen content, reducing sugars, sensory evaluation, FA composition, and volatile compound content for each LT sample were analyzed. Results The LT of KC had the highest (p<0.05) fat content, the highest reducing sugar content, and the highest scores in the sensory evaluation (flavor, tenderness, juiciness, and overall acceptance). All the sensory traits were positively correlated (p<0.001) with intramuscular fat and reducing sugar content. Several FAs and volatile compound profiles varied among the breeds. KC LT had the highest (p<0.05) concentrations of acetaldehyde, 3-methyl butanal, and 3-hydroxy-2-butanone, and these volatile compounds were positively correlated (p<0.05) with all the sensory traits. Conclusion Variations in fat content and reducing sugar contents and FA and volatile compound profiles may contribute to differences in the sensory quality of LT among breeds

Supplementation with rumen-inert fat in the growing phase altered adipogenic gene expression and the size and number of adipocytes in Hanwoo steers

International audienceAbstract We hypothesized that the provision of rumen-inert fat (RIF) to growing cattle (9 to 13 mo of age) would affect the expression of genes involved in lipid metabolism and thereby affect the size and number of adipocytes of steers slaughtered at 30 mo of age. Thirty steers with an average initial body weight (BW) of 239 ± 25 kg were allocated to six pens, balanced for BW and genetic merit for marbling, and assigned to one of two treatment groups: control (only basal diet) or test diet (basal diet with 200 g of RIF per day, on an as-fed basis) for 5 mo. Biopsy samples of longissimus lumborum (LM) muscle were then collected for analysis of fatty acid composition and gene expression. Both groups were then fed the same basal diets during the early and late fattening phases, without RIF, until slaughter (average shrunk BW = 759 kg). Supplementation with RIF increased the longissimus thoracis (LT) intramuscular fatty acid concentration at slaughter (P = 0.087) and numerically increased the quality grade score (P = 0.106). The LM intramuscular relative mRNA expression of genes such as PPARα, ZFP423 and SREBP1, FASN, SCD, FABP4, GPAT1, and DGAT2 were downregulated (P &lt; 0.1) following RIF supplementation. Supplementation of RIF decreased (P &lt; 0.1) diameter and concomitantly increased intramuscular adipocytes per viewing section at slaughter. This likely was caused by promotion of triacylglycerol hydrolysis during the growing phase. Another possible explanation is that the relative mRNA expression of gene ATGL was upregulated by RIF supplementation during the growing (P &lt; 0.1) and the fattening phases (P &lt; 0.05), while the genes associated with fatty acid uptake (FABP4) and esterification (DGAT2) were downregulated during the growing phase and upregulated (P &lt; 0.1) during the fattening phase. This implies that the lipid turnover rate was higher for steers during the growing than fattening phase. This study demonstrated that RIF supplementation during the growing phase induced a carryover effect on the lipogenic transcriptional regulation involved in adipocyte lipid content of intramuscular adipose tissue; increased triacylglycerol hydrolysis during the growing phase subsequently was followed by increased lipid accumulation during the fattening phases

Pseudoprevotella muciniphila gen. nov., sp. nov., a mucin-degrading bacterium attached to the bovine rumen epithelium.

A Gram-negative, strictly anaerobic mucin-degrading bacterium, which we designated strain E39T, was isolated from the rumen epithelium of Korean cattle. The cells were non-motile and had a coccus morphology. Growth of strain E39T was observed at 30-45°C (optimum, 39°C), pH 6.5-8.5 (optimum, pH 7.5), and in the presence of 0.0-1.0% (w/v) NaCl (optimum, 0.0-0.5%). Strain E39T contained C16:0, C18:0, C18:1 ω9c, iso-C15:0, and anteiso-C15:0 as the major fatty acids. The major polar lipids were phosphatidylethanolamine, unidentified aminophospholipid, and unidentified lipids. The major respiratory isoprenoid quinones were MK-8 and MK-9. The major fermented end-products of mucin were acetate and succinate. The G+C content of the genomic DNA was 46.4 mol%. Strain E39T was most closely related to Alloprevotella rava 81/4-12T with an 87.3% 16S rRNA gene sequence similarity. On the basis of phenotypic, chemotaxonomic, and molecular properties, strain E39T represents a novel genus of the family Prevotellaceae; as such, the name Pseudoprevotella muciniphila gen. nov., sp. nov. is proposed. A functional annotation of the whole genome sequences of P. muciniphila E39T revealed that this bacterium has a putative mucin-degrading pathway and biosynthetic pathways of extracellular polymeric substances and virulence factors which enable bacteria to adhere to the epithelial cells and avoid the host's immune responses

Electrochemical and electrocatalytic reaction characteristics of boron-incorporated graphene via a simple spin-on dopant process

Chemical doping is one of the most effective methods to tune the electrochemical properties of graphene. We report a simple and relatively low-temperature process for the fabrication of boron doped graphene by using a spin-on dopant (SOD) method. SOD-treated graphene was successfully doped with boron atoms at a temperature lower than 600 degrees C. The fabricated boron doped graphene exhibits a specific capacitance of 4 mF cm(-2), as well as a high-rate performance of 91.9% at 200 mV s(-1) as an electrode material for pseudo-capacitors. It also shows excellent oxygen reduction activity and durability with a current retention of 91.4% and methanol-tolerance properties. These features are beneficial for catalyst applications in the oxygen reduction reaction due to well-engineered boron sites with high electrical conductivity and many active sites for electrochemical reactions

Partial Substitution of Corn Grain in the Diet with Beet Pulp Reveals Increased Ruminal Acetate Proportion and Circulating Insulin Levels in Korean Cattle Steers

Simple Summary Intramuscular fat content is one of the important beef quality traits due to its contribution to beef palatability, including flavor, tenderness, and juiciness. Intramuscular fat content is determined by fat synthesis using substrates such as acetate and glucose in ruminants. Beet pulp is a byproduct of sugar beet processing and contains abundant neutral detergent fiber and pectin, with these two components readily fermentable in the rumen. Beet pulp may be a useful energy source in cattle to produce acetate during ruminal fermentation, thereby aiding in lipogenesis (fatty acid synthesis). In this study, partial substitution of corn grain in the diet with beet pulp increased ruminal acetate proportion and circulating insulin levels in beef cattle. Beet pulp could be used as a lipogenic energy source without affecting growth performance in cattle. We investigated the effects of the partial substitution of corn grain in the diet with beet pulp on growth performance, ruminal fermentation characteristics, microbial profiles, and blood lipogenic parameters in fattening steers. Twelve Korean cattle steers (body weight, 485 +/- 19.32 kg; age, 18.0 +/- 0.17 months) were equally divided into corn grain (CG) and beet pulp (BP) groups. Approximately 75% of dry matter of the requirement was offered as a concentrate portion, and the remaining 25% was offered as oat straw. Eighty percent of the concentrate portion was provided by a pelleted basal concentrate, and the remaining 20% with corn grain for the CG group, or 18% beet pulp plus 2.0% rumen-protected fat for the BP group, respectively, by top dressing. The experiment was conducted for 14 weeks, including a 2-week acclimation period. Growth rate was not affected by beet pulp feeding (p = 0.55). The molar proportions of ruminal acetate (p &lt; 0.05) on wk 4, the relative abundances of ruminal cellulolytic bacteria, including Fibrobacter succinogenes (p = 0.01) and Ruminococcus albus (p = 0.04) on wk 12, and serum insulin concentrations (p &lt; 0.05) on wk 12 were higher in the BP group than in the CG group, whereas the molar proportions of propionate (p &lt; 0.05) on wks 8 and 12 and serum nonesterified fatty acids (p &lt; 0.05) on wk 12 were lower in the BP group. Beet pulp could be used as a lipogenic energy source without affecting growth performance during the fattening period of cattle.N