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We investigated the effects of Sarcodon aspratus, Agaricus bisporus, and Lentinula edodes aqueous extracts on the tenderization of bovine longissimus dorsi muscle. Meat quality and muscle protein degradation were examined as well. Beef chunks were marinated in distilled water (control), 5% S. aspratus (SA), 5% A. bisporus (AB), or 5% L. edodes (LE) extracts. SA was shown to have a higher enzymatic activity (p

Data Availability Statement: Full-length MYH3 CDS sequence from KNP, KX538787; full-length MYH3 CDS sequence from Landrace, KX538788. Two-kb of 5’-UTR MYH3 genomic DNA sequence from KNP, KX549312; 0.5-kb of 3’-UTR MYH3 genomic DNA sequence from KNP, KX549313. Two-kb of 5’-UTR MYH3 genomic DNA sequence from Landrace, KX549311; 0.5-kb of 3’-UTR MYH3 genomic DNA sequence from Landrace, KX549314. Resequencing data access information is provided in S10 Table. All the raw data to produce figures and tables are available at https://datadryad.org/review?doi=doi:10.5061/dryad.dr32n87, Muscle development and lipid accumulation in muscle critically affect meat quality of livestock. However, the genetic factors underlying myofiber-type specification and intramuscular fat (IMF) accumulation remain to be elucidated. Using two independent intercrosses between Western commercial breeds and Korean native pigs (KNPs) and a joint linkage-linkage disequilibrium analysis, we identified a 488.1-kb region on porcine chromosome 12 that affects both reddish meat color (a*) and IMF. In this critical region, only the MYH3 gene, encoding myosin heavy chain 3, was found to be preferentially overexpressed in the skeletal muscle of KNPs. Subsequently, MYH3-transgenic mice demonstrated that this gene controls both myofiber-type specification and adipogenesis in skeletal muscle. We discovered a structural variant in the promotor/regulatory region of MYH3 for which Q allele carriers exhibited significantly higher values of a* and IMF than q allele carriers. Furthermore, chromatin immunoprecipitation and cotransfection assays showed that the structural variant in the 5'-flanking region of MYH3 abrogated the binding of the myogenic regulatory factors (MYF5, MYOD, MYOG, and MRF4). The allele distribution of MYH3 among pig populations worldwide indicated that the MYH3 Q allele is of Asian origin and likely predates domestication. In conclusion, we identified a functional regulatory sequence variant in porcine MYH3 that provides novel insights into the genetic basis of the regulation of myofiber type ratios and associated changes in IMF in pigs. The MYH3 variant can play an important role in improving pork quality in current breeding programs., This work was carried out with the support of >Cooperative Research Program for Agriculture Science & Technology Development (Project title: A research on performance improvement of ‘Nanchukmacdon’, a high quality pig breed developed using Korean native black pigs (KNP) in Jeju Island, Project No. PJ01012301 and PJ01262701)> Rural Development Administration (http://www.rda.go.kr), Republic of Korea. This work was also supported by the Korea Research Institute of Bioscience and Biotechnology (KRIBB) Research Initiative Program, Republic of Korea (www.kribb.re.kr). M.P.E work was funded by AGL2016-78709-R (Ministerio de Economía y Competitividad, Spain; http://www.mineco.gob.es/portal/site/mineco/). T

Variations of fresh meat quality exist because the quality traits are affected by various intrinsic and extrinsic factors. Because the meat quality is basically dependent on muscle fiber characteristics, numerous studies have reported the relationship between quality traits and fiber characteristics. Despite intensive research, the relationship is yet to be fully established, however, the present knowledge suggests several potential ways to manipulate muscle fiber characteristics to improve meat quality. The present paper reviews the definition of fresh meat quality, meat quality traits and variations of meat quality. Also, this review presents recent knowledge underlying the relationship between fresh meat quality traits and muscle fiber characteristics. Finally, the present work proposes several potential factors including breed, genotype, sex, hormone, growth performance, diet, muscle location, exercise and ambient temperature that can be used to manipulate muscle fiber characteristics and subsequently meat quality in animals.

Three single nucleotide polymorphisms (SNPs) in the porcine . MYOD1 gene were used for association analysis and haplotype construction to evaluate the effects of their substitution. Four hundred and three pigs of Yorkshire and Berkshire breeds were used. The mRNA expression levels of . MYOD1 were examined. The g.489. C. >. T and g.1264. C. >. A SNPs were significantly associated with several muscle fiber characteristics, the loin eye area, and lightness. Particularly, animals having hetero-genotypes of both sites showed good performance both in lean meat production and meat quality traits. The results of haplotype substitution were similar to the associations of individual SNPs. Moreover, the 2 SNPs had significant effects on mRNA expression. Therefore, the g.489. C. >. T and g.1264. C. >. A SNPs in . MYOD1 may be meaningful DNA markers that can be used for improving important porcine economic traits.

The purpose of this study was to determine the structure of the porcine PPARGC1A 5' upstream region, and to find suitable molecular markers for improved meat quality and good lean meat production. Ten DNA polymorphisms, including 7 SNPs, 2 microsatellites, and 1 insertion or deletion were newly found in the 5' upstream region of PPARGC1A. Three SNPs that had restriction enzyme site were evaluated for associations with muscle fiber characteristics and production traits. Two hundred fifty-two pigs (Yorkshire and Landrace) were used in this analysis. The c.-2894GA genotypes was significantly associated with muscle fiber characteristics, including the number of fiber type I and IIb composition (P 0.05), mean cross-sectional area of fibers (P 0.01), and fiber number per unit area (P 0.05). The animals with the GG genotype had a higher percentage of type I fibers and a lower percentage of type IIb fibers with better meat quality [higher pH value (P 0.05) and lower drip loss (P 0.05)] and lean meat production [larger loin eye area (P 0.05)]. Moreover, the mRNA expression levels of PPARGC1A among genotypes were significantly different with the highest level of GG genotype. The c.-2885GT and c.-1402AT sites showed similar results that had significant effects on the mean cross-sectional area (CSA; P 0.05), fiber number per unit area (P 0.05) and loin eye area (P 0.01). Therefore, we suggest that the c.-2894GA polymorphism in the 5' upstream region of the porcine PPARGC1A gene can be used as a meaningful molecular marker for simultaneous improvement of lean meat production and quality traits.

This study examined the effect of dietary alpha-tocopheryl acetate on lipid and cholesterol oxidation in retail packed chicken meat during refrigerated storage. Male broiler chicks were randomly assigned to five pens containing 30 chicks each, which was subjected to one of five dietary treatments (0, 50, 100, 200, or 400 IU of alpha-tocopheryl acetate/kg diet). Five different levels of alpha-tocopherol were supplied to the chicks from 3 to 6 weeks. After 42 d of feeding all the broilers were slaughtered, and the carcasses were packed in polyethylene bags individually, bags similar to those used in the retail trade, and stored for 12 d at 4 degrees C. Growth performance and fatty acid composition were not affected by the dietary alpha-tocopherol levels. The alpha-tocopherol content in breast and thigh muscles increased as the level of dietary alpha-tocopherol increased. The supplementation with 200 or 400 IU of alpha-tocopherol was more effective in reducing the level of lipid oxidation (P0.05) and total cholesterol oxidation products (P0.05). Therefore, an increase in the dietary alpha-tocopherol level from 200 to 400 IU/kg feed causes major improvements in the oxidative stability of chicken meat during refrigerated storage.

Background In the 1980s, Korean native black pigs from Jeju Island (Jeju black pigs) served as representative sample of Korean native black pigs, and efforts were made to help the species rebound from the brink of extinction, which occurred as a result of the introduction of Western pig breeds. Geographical separation of Jeju Island from the Korean peninsula has allowed Jeju black pigs not only to acquire unique characteristics but also to retain merits of rare Korean native black pigs. Results To further analyze the Jeju black pig genome, we performed whole-genome re-sequencing (average read depth of 14×) of 8 Jeju black pig and 6 Korean pigs (which live on the Korean peninsula) to compare and identify putative signatures of positive selection in Jeju black pig, the true and pure Korean native black pigs. The candidate genes potentially under positive selection in Jeju black pig support previous reports of high marbling score, rare occurrence of pale, soft, exudative (PSE) meat, but low growth rate and carcass weight compared to Western breeds. Conclusions Several candidate genes potentially under positive selection were involved in fatty acid transport and may have contributed to the unique characteristics of meat quality in JBP. Jeju black pigs can offer a unique opportunity to investigate the true genetic resource of once endangered Korean native black pigs. Further genome-wide analyses of Jeju black pigs on a larger population scale are required in order to define a conservation strategy and improvement of native pig resources. Electronic supplementary material The online version of this article (doi:10.1186/s12863-014-0160-1) contains supplementary material, which is available to authorized users.

The purpose of this study was to establish the effects of weaning age and weight on pigs, and their interaction with carcass traits and meat quality. A total of 468 piglets were obtained from 57 sows and four boars and grouped by age at weaning (D21, 18-24 days; D28, 25-32 days). Each weaning group was subdivided into three weight groups (L, M and H) according to weaning weight. The D28 group had heavier carcass weight, redness and yellowness, but had lower marbling scores and less drip loss than the D21 group (P 0.05). The pigs with a light weight at weaning had higher carcass weights and lower yellowness than did pigs with a medium or heavy weight at weaning (P 0.05). Weaning age was found to have a negative correlation with drip loss, while weaning weight was negatively correlated with carcass weight and drip loss (P 0.05). We concluded that carcass and meat quality traits in pigs were significantly related to their age and weight at weaning. Therefore, we find that piglet weaning age and weight are no less important than post-weaning growth performance and behavior, with regard to carcass traits and meat quality.

A total of six fiber types, including four pure types (type I, IIA, IIX, and IIB) and two hybrid types (type IIAX and IIXB), were classified according to the expression of myosin heavy chain (MHC) isoforms by immunohistochemistry with MHC specific monoclonal antibodies. The comparison of the muscle fiber characteristics and pork quality between pork quality groups (DFD: dark, firm, and dry; PSE: pale, soft, and exudative; RFN: reddish pink, firm, and nonexudative; and RSE: reddish pink, soft, and exudative) classified by muscle pH, drip loss, and lightness was conducted and the relationship of myofiber characteristics to pork quality was investigated. The DFD group had the highest value of IIAX fiber density (P0.05). The DFD group also showed the greatest fiber relative area of type I, IIA, and IIAX (P0.05) whereas there were no significant differences in area composition for types I, IIA, and IIAX among the other groups including PSE, RFN, and RSE (P0.05). The DFD group had the highest cross-sectional area (CSA) in types I, IIA, and IIX among the groups. The increase in density of type IIAX was related with the higher pH and the lower hue and drip loss. An increase in the fiber number composition of hybrid type IIXB increased the lightness and cooking loss and decreased sarcoplasmic protein solubility (SPS). Regarding fiber relative area, pure type I and IIA and hybrid type IIAX were greater in the DFD group and had lower lightness and drip loss. Hybrid type IIAX influences the desirability of the pork due to its association with low lightness and high pH and water-holding capacity (WHC). In contrast, type IIXB was related to poor quality pork, including pale color, low WHC in cooked meat, and low SPS.

The purpose of this study was to compare parameters associated with pork quality, muscle fiber, and eating quality among various breeds, and to examine if differences in eating quality were associated to pork quality and muscle fiber characteristics. For carcass and pork quality, although there were significant differences among breeds, the values of parameters in all pigs were assigned a normal quality class, a likely outcome of the similarity in the area percentage of type I and IIB fibers. For eating quality, pork loins from Berkshire pigs were more tender and full of pork flavor than Landrace and Yorkshire pigs. Except juiciness and mouth coating, over 20% of the variability in the eating quality parameters can be explained by pork quality traits and muscle fiber characteristics using multiple regression analysis. Furthermore, differences in muscle pH(24h), cooking loss, shear force, and NPPC marbling score could explain a large proportion of variation in eating quality parameters associated with the texture of pork.