Higher Intramuscular Fat Research Articles

Effects of Dietary Energy on Growth Performance, Rumen Fermentation and Bacterial Community, and Meat Quality of Holstein-Friesians Bulls Slaughtered at Different Ages.

Simple SummaryBeef tenderness, flavour and juiciness are quality characteristics of consumer eating satisfaction. Marbling level of beef could determine quality characteristics by concentrating water soluble flavour molecules and releasing low fat-solubility volatiles faster. Increasing number of Holstein-Friesians bulls are used for beef production, and this breed is considered to have lower meat quality than purebred and crossbred beef cattle. Therefore, in this study we designed different dietary energy levels and slaughter ages to find ways to improve the meat quality of Holstein-Friesians bulls in beef production. We found that Holstein-Friesians bulls fed with 10.90 and 11.68 MJ/kg metabolizable energy diets, compared to a diet with 10.12 MJ/kg of metabolizable energy, had higher average daily gain, dressing percentage, intramuscular fat content and water holding capacity at 23 or 26 months of age. This study provides a basis to use bulls to produce beef by providing indicators of growth performance, rumen fermentation and ruminal bacteria community, and meat quality.The objective of this study was to evaluate the effects of dietary energy levels on growth performance, rumen fermentation and bacterial community, and meat quality of Holstein-Friesians bulls slaughtered at different ages. Thirty-six Holstein-Friesians bulls (17 months of age) were divided into a 3 × 3 factorial experiment with three energy levels (LE, ME and HE; metabolizable energy is 10.12, 10.90 and 11.68 MJ/kg, respectively) of diets, and three slaughter ages (20, 23 and 26 months). Results indicated that bulls fed with ME and HE diets had higher dry matter intake, average daily gain, and dressing percentage at 23 or 26 months of age. The ME and HE diets also reduced bacterial diversity, altered relative abundances of bacteria and produced lower concentrations of acetate, but higher butyrate and valerate concentrations in rumen fluid. Increasing in dietary energy and slaughter age increased the intramuscular fat (IMF) and water holding capacity. In summary, Holstein-Friesians bulls fed with ME and HE diets, slaughtered at 23 and 26 months of age could be a good choice to produce beef with high IMF. Slaughter age may have less influence than dietary energy in altering fermentation by increasing amylolytic bacteria and decreasing cellulolytic bacteria, and thus, further affecting meat quality.

Evaluation of the Changes in Composition of Pork Chops During Cooking

ObjectivesThe objective was to determine the change in extractable lipid concentration during cooking of boneless pork chops to different endpoint temperatures. Intramuscular fat (IMF) concentration of pork chops changes during the cooking process when chops are cooked to 63°C, water is lost thereby concentrating extractable lipid. When chops are cooked to 71°C, water is lost, but it was hypothesized that lipid is lost as well. This would result in less variability in IMF of cooked chops compared with raw chops. This reduction in variability may explain the lack of sensory perception differences between chops with substantial marbling and chops with little marbling. This is important because consumers use marbling to make purchasing decisions. The hypothesis was that the range in IMF would be lessened after cooking due to moisture loss and potentially lipid loss at higher cooking temperatures. Ultimately, the variation in IMF in cooked pork chops would be less than that of fresh pork chops.Materials and MethodsPork loins (152 total) were used by cutting 3 consecutive chops from each loin. Chop 1 was evaluated raw (not cooked), chop 2 was cooked to 63°C, and chop 3 was cooked to 71°C before evaluation for IMF. These chops were divided into 3 separate bins based on raw IMF percentages. The low group consisted of chops with an IMF percentage equal to or less than 3%, the average group consisted of IMF percentages between 3 and 4% and the high IMF group consisted of chops with an IMF greater than 4%. Moisture and IMF were determined using duplicate 10-g samples from each chop. Samples were dried and IMF was determined with the chloroform-methanol solvent method. Cook loss was calculated by weighing chops before and after cooking. Warner-Bratzler Shear Force (WBSF) was determined by shearing 5 cores from each chop. Data were analyzed using a one-way ANOVA with the fixed effect of IMF level. Means were separated using a probability of difference statement and considered significantly different at P < 0.05.ResultsRaw high IMF chops (4.94%) had greater (P < 0.0001) IMF than average IMF chops (3.51%). Raw average IMF chops (3.51%) had greater (P < 0.0001) IMF than low IMF chops (2.47%). High IMF chops cooked to 63°C (5.59%) had greater (P < 0.0001) IMF than average IMF chops cooked to 63°C (4.17%). Average IMF chops cooked to 63°C (4.17%) had greater (P < 0.0001) IMF than low IMF chops cooked to 63°C (3.39%). High IMF chops cooked to 71°C (6.12%) had greater (P < 0.0001) IMF than average IMF chops cooked to 71°C (4.55%). Average IMF chops cooked to 71°C (4.55%) had greater (P < 0.0001) IMF than low IMF chops cooked to 71°C (3.88%). Additionally, WBSF was not different (P ≥ 0.32) among high, average or low groups when cooked to 63°C or 71°C. Cook loss was not different (P ≥ 0.31) among high, average, or low groups when cooked to 63°C or 71°C. However, WBSF (2.77 kg) and cook loss (18.70%) was less in chops cooked to 63°C than when cooked to 71°C (3.10 kg, 23.37%).ConclusionThe hypothesis was that the range and variability in IMF would be lessened after cooking due to moisture loss and potentially lipid loss at higher cooking temperatures. This was not the case and the differences in IMF percentages persisted even after cooking. Furthermore, WBSF and cook loss did not differ among chops categorized as high, average, and low IMF categories. Ultimately, IMF percentage of raw or cooked chops did not affect tenderness.

Influence of Farm Management for Calves on Growth Performance and Meat Quality Traits Duration Fattening of Simmental Bulls and Heifers.

Simple SummaryCattle have been selected for their adaptation to a specific environment and productive system, in which they show, in theory, their best economical results. With appropriate nutrition, the calf’s performance enhances during early life and improve the production limit providing distinctive opportunities to optimize feeding strategies and increase the profitability of beef production. There is considerable variation in fattening protocols as well as in farm conditions. Meat quality parameters and carcass traits are the main objectives of most research carried out in the beef production area. Optimizing meat quality parameters and carcass traits are important for farmer profits and consumer satisfaction. According to that, at the phenotypic level, growth performance and traits could be observed. Rearing practices are known to have an impact on cattle carcasses and meat characteristics. The rearing practices applied after calving have an influence on the animal’s performance at the growth period and can involve different animal properties at the beginning of the fattening period.This study assessed the effects of farm management during rearing practices in the first months of a calf’s life on growth performance and meat quality traits during the fattening period. A total of 48 Simmental calves were divided into two groups at a commercial cattle feedlot. In the first group were calves from the same farm and herd (n = 12 male and n = 12 female). The second group included calves from several different herds and farms (n = 12 male and n= 12 female). Calves were transferred to a feedlot and fed with a commercial feedlot ration at three to four months of age. The aim was to determine if identical fattening conditions at feedlot can reduce initial calf rearing differences between cattle during the fattening period. Bulls grew faster than heifers reaching higher total gain and showed significantly higher slaughter weight than heifers. Meat samples of heifers from the same herd had the highest intramuscular fat content and reddest color with significant differences among cattle groups. The most abundant fatty acid was oleic acid (C18:1), followed by palmitic (C16:0), stearic (C18:0), linoleic (C18:2), and myristic acid (C14:0). Meat samples of heifers from different herds were darkest with highest content of iron (Fe) with significant differences among cattle groups.

Dietary vitamin E supplementation reduces lamb meat browning on display following up to 70 days of chilled storage

Rapid browning limits the retail display of lamb meat, particularly following extended chilled storage that is typical of international shipment. Lamb stored chilled for short periods browns more rapidly on retail display when the meat has high levels of marbling (intramuscular fat), a high pH or greater oxidative capacity. In contrast, high muscle vitamin E concentration reduces browning of short stored lamb meat on retail display. However, the capacity of dietary vitamin E supplementation to reduce retail browning in lamb meat following extended chilled storage is unknown. Additionally, the ability of vitamin E to mitigate the negative impacts of intramuscular fat, pH and oxidative capacity on meat browning following chilled storage is unknown. Sixty six industry sires of Terminal, Merino and Maternal breed types were bred with Merino and Merino-cross dams to produce 132 lambs. The two lambs from each sire were divided into two vitamin E treatment groups that were housed in 12 pens (6 pens per treatment) for 8 weeks leading up to slaughter. Control lambs (6 pens of 11 lambs) were fed a pelleted ration containing basal levels of vitamin E (30 mg/kg feed) while supplemented lambs (6 pens of 11 lambs) were fed the same ration with increased vitamin E content (275 mg/kg feed). After slaughter, the m. longissimus lumborum was sampled for measurement of vitamin E concentration, intramuscular fat, pH, oxidative enzyme isocitrate dehydrogenase activity, and retail meat colour. Colour samples were vacuum packaged for storage at −1 °C for 5, 35 and 70 d, before being re-sliced, wrapped and placed under stimulated retail display where meat redness (R630/R580) was measured 24 hourly for 72 h. Lamb pens supplemented with vitamin E produced redder loin meat at 24, 48 and 72 h of display compared to control pens of lambs (P < 0.05), regardless of storage time. Increasing muscle vitamin E concentration from 0.8 to 4 mg/g of loin muscle improved meat redness to a slightly greater extent in meat stored for 35 d than 5 or 70 d (P < 0.05). High intramuscular fat reduced redness in 5 day stored lamb (P < 0.05) and increasing muscle vitamin E had a greater effect improving the display colour in this highly marbled meat. These results demonstrate that dietary vitamin E supplementation will improve the display colour of highly marbled or long stored lamb meat.

Comparison of slaughter performance, meat traits, serum lipid parameters and fat tissue between Chaohu ducks with high- and low-intramuscular fat content

This study was conducted to investigate the effect of intramuscular fat (IMF) on carcass traits of Chaohu ducks. Two-hundred-forty ducks were separated by sex and raised in separate pens. Slaughter performance, meat quality, and serum lipid parameters were identified. Based on IMF, samples were divided into males with high IMF (CHM) or low IMF (CLM) and females with high IMF (CHF) or low IMF (CLF). There were significant differences in the living body weight, abdominal fat ratio (%), shear force, IMF, total cholesterol (TC), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) content between female and male ducks. In addition, compared with the CLM group, the shear force (p = 0.001) was significantly greater but the lightness (p = 0.006) was lower in the CHM group. TC, HDL and LDL content were also significantly higher (p = 0.033, 0.027 and 0.012, respectively) in the CHM group. The butcher ratio (0.028), eviscerating rate (0.039) and breast meat ratio (0.028) in the CHF group was significantly lower than that in CLF group, while these parameters showed no difference between CHM and CLM. In conclusion, IMF had a significantly positive correlation with subcutaneous fat and abdominal fat and was also positively correlated with TC, HDL and LDL in Chaohu ducks.

Meat quality, fatty acids, volatile compounds, and antioxidant properties of lambs fed pasture versus mixed diet.

The aim of the present work was to investigate the effects of feeding regimens (pasture vs. mixed diet) on meat quality, fatty acids, volatile compounds, and antioxidant properties in lamb meat. In total, 24 lambs were allotted into two feeding regimens at 10.23 kg live weight. Lambs were fed on pasture grass (PG group, n = 12) or mixed diet (M group, n = 12). Longissimus thoracis (LT) muscle samples from the M group had a higher intramuscular fat (IMF) (p < 0.05), pH45minvalue (p < 0.01), and ash (p < 0.05) than the PG group. In contrast, the shear force (p < 0.05), L*(p < 0.05), and b* (p < 0.001) in M group were lower than in PG group. Analyses indicated that PG group contained higher linolenic acid (C18:3n3) and docosatrienoic acid (C22:3n6) (p < 0.05) than the M group. Major volatile compounds in the muscles included hexanal, heptanal, nonanal, octanal, 1‐pentanol, 1‐hexanol, 1‐octen‐3‐ol, and 2,3‐octanedione. The levels of hexanal, nonanal, and 2,3‐octanedione were significantly lower in PG lamb muscle (p < 0.01). In contrast, 1‐pentanol and 1‐hexanol levels were higher in M lamb muscle (p < 0.01). Muscle from PG lamb exhibited higher catalase (CAT) and glutathione peroxidase (GPx) activity (p < 0.05). PG muscle also contained a higher radical‐scavenging ability (RSA; p < 0.001) and cupric‐reducing antioxidant capacity (CUPRAC; p < 0.05). Overall, the improved antioxidant status in PG muscle inhibited lipid peroxidation (aldehydes and ketones), thereby improving the meat quality.

The Changes of the Volatile Compounds Derived from Lipid Oxidation of Boneless Dry‐Cured Hams During Processing

The generation of aroma during processing of boneless dry‐cured hams is investigated by evaluating neutral and acid lipases, phospholipase, lipoxygenase (LOX), thiobarbituric acid reactive substances (TBARS) values, fatty acid composition, and volatile substances derived from lipid oxidation (VCDFLO). It is found that moisture content, acid lipase, and phospholipase decreases in the whole processing, but sodium chloride content and TBARS increase. Neutral lipase, LOX, and total fatty acids increase from raw ham to the end of resting and decrease subsequently. 15 VCDFLO containing six ketones, three aldehydes, three hydrocarbons, one alcohol, one carboxylic acid, and one furan are identified. The total peak area of VCDFLO increases during the entire processing and indicates 39.76–40.75% of total volatile compounds. Hexanal, 1‐octen‐3‐ol, octanal, and nonanal are the major characteristic volatiles of boneless dry‐cured hams. Therefore, VCDFLO formation is associated with lipid‐related enzymes and helpful for the aroma.Practical Applications: The pork that has high intramuscular fat content is usually selected to produce boneless dry‐cured hams, because intramuscular phospholipids, and triglycerides are important precursors to produce aroma compounds. Exploring the formation mechanism of flavor associated with lipid oxidation will be beneficial for improving the quality of hams. Therefore, this study demonstrates the relationship between lipolysis‐oxidation and the generation of flavor compounds during the processing of boneless dry‐cured hams.This study demonstrates that thiobarbituric acid reactive substances (TBARS) values can reveal the changed trend of volatile compounds derived from lipid oxidation (VCDFLO) very well, and that lipid‐related enzymes plays an important role in the development of VCDFLO.

Adding heat-treated rapeseed to the diet of yak improves growth performance and tenderness and nutritional quality of the meat.

Heat-treated rapeseed was supplemented to indoor fed yaks in winter to test the effect on dry matter intake (DMI), body mass change, and meat quality. Sixteen 3-year-old yak steers (124±15.3kg) were divided randomly into two groups and were offered either heat-treated rapeseed (HTR) or rapeseed meal (CONT). The yaks were allowed 14days for adjustment and measurements were made over 120 d. There was no difference in DMI between groups (p=0.67), but average daily gain tended to be higher (p<0.056) and feed to gain ratio tended to be lower (p=0.050) in HTR than in CONT yaks. Meat from HTR yaks was more tender (p=0.006), had higher intramuscular fat (p=0.013), and had lower cholesterol content (p=0.009) than from CONT yaks. In addition, the atherogenic index was lower (0.37 vs. 0.43; p=0.049), the PUFA:SFA ratio was higher (0.55 vs. 0.37; p=0.049), and the n-6:n-3 (n-6 PUFA to n-3 PUFA) ratio was lower (2.76 vs. 4.78; p=0.003) in HTR than in CONT yaks, which all favoured the HTR yaks. Meat from HTR yaks met human health standards of a PUFA:SFA ratio of above 0.4 and n-6:n-3 ratio of less than 4, whereas meat from CONT yaks just missed these standards.

Suckler Bulls Slaughtered at 15 Months of Age: Effect of Different Production Systems on the Fatty Acid Profile and Selected Quality Characteristics of Longissimus Thoracis.

The objective was to compare the quality of beef from bulls reared in typical Irish indoor systems or in novel grass-based systems. Bulls were assigned to one of the following systems: (a) grass silage plus barley-based concentrate ad libitum (CON); (b) grass silage ad libitum plus 5 kg of concentrate (SC); (c) grazed grass without supplementation (G0); (d) grazed grass plus 0.5 kg of the dietary dry matter intake as concentrate (GC) for (100 days) until slaughter (14.99 months). Carcass characteristics and pH decline were recorded. Longissimus thoracis was collected for analytical and sensory analysis. Lower carcass weight, conformation and fatness scores were found for grazing compared to CON and SC groups. CON bulls had highest intramuscular fat and lighter meat colour compared with grazing bulls. The SC meat (14 days aged) was rated higher for tenderness, texture, flavour and acceptability compared with grazing groups. CON saturated and monounsaturated fatty acid (FA) concentration was highest, conversely, omega-3 FA concentration was higher for GC compared with CON, while no differences were found in polyunsaturated FA. In conclusion, while market fatness specification was not reached by grazed grass treatments, beef eating quality was not detrimentally affected and nutritional quality was improved.

Efficacy of ω-3 supplementation on nutritional status, skeletal muscle, and chemoradiotherapy toxicity in cervical cancer patients: A randomized, triple-blind, clinical trial conducted in a middle-income country.

Supplementation with ω-3 has been shown to favor the preservation of body weight and skeletal muscle. The aim of this study was to evaluate the efficacy of ω-3 supplementation on nutritional status, skeletal muscle quantity and quality, and toxicity for treatment of women with cervical cancer. This was a randomized, triple-blinded, placebo-controlled clinical trial in women diagnosed with cervical cancer who underwent chemoradiotherapy between March 2016 and August 2017. The intervention group received four capsules with ω-3 (2.5 g/d) and the control group (CG) received the same number of identical-looking capsules with olive oil, for 45 d. Nutritional status was measured by anthropometry and Patient-Generated Subjective Global Assessment. Body composition was assessed by computed tomography. The skeletal muscle index was calculated using the range -29 to +150 HU. For skeletal muscle quality, the area comprised between -29 and +29 HU was denominated low-radiodensity skeletal muscle index and the range between +30 and +150 HU high-radiodensity skeletal muscle index, representing the skeletal muscle area with high or low intramuscular fat infiltration, respectively. The study population comprised 40 patients, with an average age 44.53 ± 8.73. The intervention group maintained body weight and showed an improvement in Patient-Generated Subjective Global Assessment score. A significant reduction in skeletal muscle index was observed in both groups. However, in regard to skeletal muscle quality, patients in the intervention group preserved low- and high-radiodensity skeletal muscle index, whereas those in the control group had increased low-radiodensity skeletal muscle index and significantly reduced high-radiodensity skeletal muscle index, reflecting high intramuscular fat infiltration only in the control group. The incidence of chemotherapy toxicity was significantly lower in the intervention group. The results suggest that ω-3 supplementation is effective in maintaining nutritional status, skeletal muscle quality, and reduced symptoms of chemoradiotherapy among women with cervical cancer.

Expression and single-nucleotide polymorphisms of the H-FABP gene in pigs

Heart fatty acid-binding protein (H-FABP) belongs to a family of intracellular fatty acid-binding proteins that are involved in the transport of long-chain fatty acids. Previous studies have indicated that H-FABP is significantly associated with intramuscular fat (IMF) content in pig. In this study, we compared the mRNA and protein expression of H-FABP between Tibetan pig (with high IMF) and Large White pig (with low IMF). The expression of H-FABP at both mRNA and protein levels in the tissues of backfat, longissimus dorsi muscle and liver was found to be significantly higher in TP than in LW. Single-nucleotide polymorphisms (SNPs) in a 2 kb region upstream of the start codon of the gene were screened using Sanger sequencing. We accordingly identified three SNPs (C-1375G, C-314T and T-158G) between the TP and LW populations and genotyped these based on PCR-restriction fragment length polymorphisms (PCF-RFLPs) analysis. The results showed that the C-1375G site might regulate H-FABP gene expression and thus be associated with fat deposition in pigs. Our study provides important data for further investigating the regulatory mechanism of H-FABP for fat deposition in pigs.

Comparison of liver transcriptome from high- and low-intramuscular fat Chaohu ducks provided additional candidate genes for lipid selection.

The meat quality of ducks is closely related to the intramuscular fat (IMF) content. This study explored the candidate regulatory genes of IMF formation and lipid deposition in Chaohu ducks. The IMF of breast muscle in 100 ducks was determined and statistically analysed by normal distribution test. Duck liver samples with high IMF (CH, n = 3) and low IMF (CL, n = 3) were selected for transcriptome analysis by RNA sequencing (RNA-Seq). The IMF was in accordance with normal distribution (T = 0.001, P = 0.999). The IMF from two tails of the normal distribution was significantly different with 2.9983% ± 0.3296% in the CH group and 1.1960% ± 0.1481% in the CL group (P < 0.0001). RNA-Seq revealed 147 differentially expressed genes, including 78 up-regulated and 69 down-regulated genes in both groups. Validation by qRT-PCR was in agreement with RNA-Seq (R 2 = 0.838). Gene ontology analysis revealed that organophosphate catabolism, oxidation-reduction process, cellular lipid catabolism, lipid transport, lipid localisation, lipid biosynthesis and cellular lipid catabolism were involved in lipid metabolism. Meanwhile, Kyoto Encyclopedia of Genes and Genomes pathway analysis suggested that steroid hormone biosynthesis, ovarian steroidogenesis, alpha-linolenic acid metabolism, glycosylphosphatidylinositol anchor biosynthesis and linoleic acid metabolism were involved in lipid deposition, wherein the genes COMT, NT5E, PDE4D, PLA2G4F, A-FABP, ADRA2A, HSD17B2, PPP1R3C, PPP1R3B and NR0B2 were involved in lipid deposition. This study provided insights into the molecular mechanism for regulating lipid metabolism and identified candidate genes for selecting markers to control IMF formation in Chaohu ducks.

Gene expression of Hanwoo satellite cell differentiation in longissimus dorsi and semimembranosus

BackgroundKorean Hanwoo cattle are known for their high meat quality, especially their high intramuscular fat compared to most other cattle breeds. Different muscles have very different meat quality traits and a study of the myogenic process in satellite cells can help us better understand the genes and pathways that regulate this process and how muscles differentiate.ResultsCell cultures of Longissimus dorsi muscle differentiated from myoblast into multinucleated myotubes faster than semimembranosus. Time-series RNA-seq identified a total of 13 differentially expressed genes between the two muscles during their development. These genes seem to be involved in determining muscle lineage development and appear to modulate the expression of myogenic regulatory factors (mainly MYOD and MYF5) during differentiation of satellite cells into multinucleate myotubes. Gene ontology enriched terms were consistent with the morphological changes observed in the histology. Most of the over-represented terms and genes expressed during myoblast differentiation were similar regardless of muscle type which indicates a highly conserved myogenic process albeit the rates of differentiation being different. There were more differences in the enriched GO terms during the end of proliferation compared to myoblast differentiation.ConclusionsThe use of satellite cells from newborn Hanwoo calves appears to be a good model to study embryonic myogenesis in muscle. Our findings provide evidence that the differential expression of HOXB2, HOXB4, HOXB9, HOXC8, FOXD1, IGFN1, ZIC2, ZIC4, HOXA11, HOXC11, PITX1, SIM2 and TBX4 genes could be involved in the differentiation of Longissimus dorsi and Semimembranosus muscles. These genes seem to modulate the muscle fate of the satellite cells during myogenesis through a differential expression profile that also controls the expression of some myogenic regulatory factors (MYOD and MYF5). The number of differentially expressed genes across time was unsurprisingly large. In relation to the baseline day 0, there were 631, 155, 175, 519 and 586 DE genes in LD, while in SM we found 204, 0, 615, 761 and 1154 DE genes at days 1, 2, 4, 7 and 14 respectively.

Emotional responses to the consumption of dry-cured hams by Spanish consumers: A temporal approach

The objective of this study was to describe for the first time the emotional responses during the consumption of three types of Spanish dry-cured hams, namely, ‘Iberian’, ‘Serrano’ and ‘Curado’. Moreover, dynamic sensory techniques such as Temporal Dominance of Emotions and Temporal Dominance of Sensations were applied to identify the dominant emotions and sensory attributes perceived during ham consumption. >50 emotional terms were generated during sample consumption including positive, negative and neutral terms. Noticeable differences were detected among the three types of dry-cured ham for their emotional profiles. The most dominant emotions evoked by Iberian dry-cured hams were “intense”, “authentic” and “pleasant” and could be associated with the domination of cured flavour and juiciness, with both attributes being closely related to their high intramuscular fat content. However, in Serrano and Curado dry-cured hams, the domination of saltiness attribute seemed to contribute to evoking negative emotions as “ordinary”, “indifferent” and “dissatisfied”. Finally, high duration of the domination of positive emotions as “desirable”, “intense”, “pleasant” and “authentic” contributed to high overall liking scores.

Genome-wide association study for intramuscular fat content in Chinese Lulai black pigs.

ObjectiveIntramuscular fat (IMF) content plays an important role in meat quality. Identification of single nucleotide polymorphisms (SNPs) and genes related to pig IMF, especially using pig populations with high IMF content variation, can help to establish novel molecular breeding tools for optimizing IMF in pork and unveil the mechanisms that underlie fat metabolism.MethodsWe collected muscle samples of 453 Chinese Lulai black pigs, measured IMF content by Soxhlet petroleum-ether extraction method, and genotyped genome-wide SNPs using GeneSeek Genomic Profiler Porcine HD BeadChip. Then a genome-wide association study was performed using a linear mixed model implemented in the GEMMA software.ResultsA total of 43 SNPs were identified to be significantly associated with IMF content by the cutoff p<0.001. Among these significant SNPs, the greatest number of SNPs (n = 19) were detected on Chr.9, and two linkage disequilibrium blocks were formed among them. Additionally, 17 significant SNPs are mapped to previously reported quantitative trait loci (QTLs) of IMF and confirmed previous QTLs studies. Forty-two annotated genes centering these significant SNPs were obtained from Ensembl database. Overrepresentation test of pathways and gene ontology (GO) terms revealed some enriched reactome pathways and GO terms, which mainly involved regulation of basic material transport, energy metabolic process and signaling pathway.ConclusionThese findings improve our understanding of the genetic architecture of IMF content in pork and facilitate the follow-up study of fine-mapping genes that influence fat deposition in muscle.

Evaluation of DNA damage and modulation of gene expression in the heart of rats that received vitamin D3 supplemented or deficient diets

Excess adiposity is a well-known risk factor for heart failure (HF). Fat accumulation in and around the peripheral skeletal muscle may further inform risk for HF.The purpose of this study was to evaluate the association between intramuscular and intermuscular fat deposition and incident HF in a longitudinal cohort of community-dwelling older adults.The associations of intramuscular and intermuscular fat with incident HF were assessed using Cox models among 2,399 participants from the Health ABC (Health, Aging and Body Composition) study (70-79 years of age, 48% male, 40.2% Black) without baseline HF. Intramuscular fat was determined by bilateral thigh muscle density on computed tomography and intermuscular fat area was determined with computed tomography.After a median follow-up of 12.2 years, there were 485 incident HF events. Higher sex-specific tertiles of intramuscular and intermuscular fat were each associated with HF risk. After multivariable adjustment for age, sex, race, education, blood pressure, fasting blood sugar, current smoking, prevalent coronary disease, and creatinine, higher intramuscular fat, but not intermuscular fat, was associated with higher risk for HF (HR: 1.34 [95% CI: 1.06-1.69]; P = 0.012, tertile 3 vs tertile 1). This association remained significant after additional adjustment for body mass index (HR: 1.32 [95% CI: 1.03-1.69]), total percent fat (HR: 1.33 [95% CI: 1.03-1.72]), visceral fat (HR: 1.30 [95% CI: 1.01-1.65]), and indexed thigh muscle strength (HR: 1.30 [95% CI: 1.03-1.64]). The association between higher intramuscular fat and HF appeared specific to higher risk of incident HF with reduced ejection fraction (HR: 1.53 [95% CI: 1.03-2.29]), but not with HF with preserved ejection fraction (HR: 1.28 [95% CI: 0.82-1.98]).Intramuscular, but not intermuscular, thigh muscle fat is independently associated with HF after adjustment for cardiometabolic risk factors and other measurements of adiposity.

Growth, carcass characteristics and meat quality of Chinese indigenous Yanan pig crossbred with Duroc and Berkshire genotypes

The objective of the present study was to evaluate the effects of crossbreeding on the growth, carcass characteristics and meat quality of Chinese native Yanan (YN) pig breed and related crossbreeds, including Duroc × Yanan (DY) and Duroc × (Berkshire × Yanan) (DBY). In total, 60 pigs (20 per breed) were used in the study. The results showed that both crossbreeds, especially DBY pigs, exhibited improved growth and carcass characteristics compared with those of purebred YN pigs. Moreover, the two crossbreeds, especially DBY pigs, produced acceptable meat-quality characteristics (normal pH and meat-colour values, high intramuscular fat content and water-holding capacity, acceptable muscle-fibre parameters, and strong pork flavour) similar to those of YN pigs. M. longissimus lumborum contained eight essential amino acids, with high contents in all pigs. C18:1, C16:0, C18:0, and C18:2 were the main fatty acids in M. longissimus lumborum in the three breeds, and a polyunsaturated:saturated fatty acid ratio of ~0.2 was observed in DBY and YN pigs. These results indicated that DBY pigs exhibit an acceptable total production performance and could be extensively used in commercial pig production to provide high-quality niche products.

Evaluation of a new select-breeding carp variety with high fillet quality

The morphological characters, fillet texture, and nutrient contents of the F3 generation of Barbless carp (Cyprinus pellegrini,BC) female × Heilongjiang carp (Cyprinus carpio,HLC, geographical population of common carp) male hybrid, which were named as High-quality carp F3 (HQC F3), were studied. The main morphological characteristics of HQC F3 were between BC and HLC, but closer to the BC. The fillet amino acids and crude protein showed significant differences between HQC F3 and BC. But, only fillet crude fat showed significant differences between HQC F3 and HLC. HQC F3's fillet had significantly different with BC's on the contents of myristic acid, linolenic acid, and stearic acid, and with HLC's on the contents of linoleic acid, linolenic acid, EPA, palm oleic acid, and 20 carbon-dilute acid. HQC F3 broodstocks were selected with high intramuscular fat and effective population size. HQC F4 were bred and showed improved intramuscular fat content compared to F3. The intramuscular fat of 2-year-old HLC F4 was significantly (p < 0.05) correlated with body weight/standard length. Intramuscular fat is a stable trait that can be continuously passed on to the next generation. This study will lay a foundation for further carp selective breeding study to improve fillet quality.

Multivariate genome-wide association studies on tenderness of Berkshire and Duroc pig breeds.

Genome-wide association studies (GWAS) have been steadily used for identification of genomic links to disease and various economical traits. Of those traits, a tenderness of pork is one of the most important factors in quality evaluation of consumers. In this study, we use two pig breed populations; Berkshire is known for its excellent meat quality and Duroc which is known for its high intramuscular fat content in meat. Multivariate genome-wide association studies (MV-GWAS) was executed to compare SNPs of two pigs to find out what genetic variants occur the tenderness of pork. Through MV-GWAS, we have identified candidate genes and the association of biological pathways involved in the tenderness of pork. From these direct and indirect associations, we displayed the usefulness of simple statistical models and their potential contribution to improving the meat quality of pork. We identified a candidate gene related to the tenderness in only Berkshire. Furthermore, several of the biological pathways involved in tenderness in both Berkshire and Duroc were found. The candidate genes identified in this study will be helpful to use them in breeding programs for improving pork quality.

Evaluación de la calidad de las paletas curados de diferentes líneas genéticas de cerdos Ibéricos

In this work the comparative quality of dry cured shoulders was studied from different genetic lines: Retinto x Entrepelado RxT (n=6), Torbiscal TxT (n=6), Entrepelado ExE (n=10), Retinto RxR (n=6) and Entrepelado x Torbiscal TxE/ExT (n=8). Dry-cured shoulders were evaluated w1tr EVACAL method, an original method from SiPA. This method includes physico-chemical analys1s (moisture, intramuscular fat, proteins, NaCI, myoglobin, fatty acid profile, volatile compound s and lipid oxidation), instrumental analysis (instrumental colour, pH and texture) and sensory analysis. The obtained results exposed that RxR batch shows a higher ratio in oleic/steric and MUFAISAT, which is related with a high quality. This was confirmed in the sensory analysis with high scores of fat fluidity and lean brightness. The TxE/ExT batch is characterized by high quantities of myoglobin which resulted in high quantities of volatile compounds from aminoacid (2-metylbutanal y 3-metylbutan al). These facts were shown in the sensory analysis results with higher flavour persistence and higher juiciness in comparison with the other batches. Moreover, RxE batch reveals a high quantity oi intramuscular fat and higher scores in sensory attributes regarding the appearance (fat fluidity), texture (juiciness) and odour intensity in comparison with the other batches. We can conclude that there are three genetics lines which result in high quality products. The convenience of using one of these depends on other aspects like the prolificacy.