1,721,198 research outputs found
Mitochondrial respiratory activity in porcine longissimus muscle fibers of different pig genetics in relation to their meat quality
No full textThe pig genetics of Duroc, Pietrain (MHS homozygote negative, PiNN), Pietrain (MHS homozygote positive, PiPP) and a F2-Duroc-Pietrain cross-breed were analyzed. The animals had comparable (P > 0.05) carcass weights, but the PiPP pigs had higher carcass yield and lean meat values (P < 0.05). Considering the meat quality characteristics, the PiPP showed a faster pH drop and higher electrical conductivity, drip loss, shear force as well as lightness and redness values (P < 0.05). The PiPP animals had less slow-twitch-oxidative (STO) and more fast-twitch-glycolytic (FTG) muscle fibers, whereas the results of the Duroc animals were converse (P < 0.05). The STO and FTG fibers of the PiPP animals were larger than those of the other genetics (P < 0.05). The analysis of the mitochondrial respiratory activity (MRA) using permeabilized longissimus muscle fibers resulted in no differences between the pig genetics before and immediately after slaughter. During chilling the MRA decreased in all pigs but to a higher extent in the PiPP pigs (P < 0.05). (C) 2009 Elsevier Ltd. All rights reserved.Deutsche Forschungsgemeinschaft [WE 4079/1-1
Changes of the activities of glycolytic enzymes before and after slaughter of pigs and the relation to stress susceptibility of the animals
No full textIn the present study slaughter and meat quality characteristics as well as the activities of the glycogen-phosphorylase (GP), phosphofructokinase (PFK) and lactate dehydrogenase (LDH) - determined at different times before (24 h a.m.) and after (1 min p.m., 40 min p.m., 24 h p.m.) slaughter - of each 32 pigs of the genetics Pietrain with (PiPP) and without mutation (PiNN) in the gene of the ryanodine receptor (RyR) were investigated. In both experimental groups half of the animals were female. The PiPP pigs had significantly higher slaughter yields and meat percentages and significantly lower pH factors as well as higher electrical conductivity values and drip losses. Beside this the meat of these pigs was brighter (L ). The GP activities increase 1 min p.m. significantly then dropping with the following measurement 40 min p.m. again to the level determined 24 h a.m.. The activities of the PFK also increase shortly after slaughter (1 min p.m.), but remained at high level (40 min p.m.) before the activity dropped again 12 h p.m.. An increase of the LDH activities could be determined 40 min p.m., while at all other determination times the values were comparable. Differences between the genetics existed concerning the higher GP activities 1 min p.m. and the lower PFK activities 1 min and 40 min p.m. in the meat of the PiPP pigs. The investigation shows that the examined enzymes are involved in the meat development, whereas only the GP seems to influence the altered meat quality of the PiPP pigs
Changes of the activities of glycolytic enzymes before and after slaughter of pigs and the relation to stress susceptibility of the animals
No full textIn the present study slaughter and meat quality characteristics as well as the activities of the glycogen-phosphorylase (GP), phosphofructokinase (PFK) and lactate dehydrogenase (LDH) - determined at different times before (24 h a.m.) and after (1 min p.m., 40 min p.m., 24 h p.m.) slaughter - of each 32 pigs of the genetics Pietrain with (PiPP) and without mutation (PiNN) in the gene of the ryanodine receptor (RyR) were investigated. In both experimental groups half of the animals were female. The PiPP pigs had significantly higher slaughter yields and meat percentages and significantly lower pH factors as well as higher electrical conductivity values and drip losses. Beside this the meat of these pigs was brighter (L ). The GP activities increase 1 min p.m. significantly then dropping with the following measurement 40 min p.m. again to the level determined 24 h a.m.. The activities of the PFK also increase shortly after slaughter (1 min p.m.), but remained at high level (40 min p.m.) before the activity dropped again 12 h p.m.. An increase of the LDH activities could be determined 40 min p.m., while at all other determination times the values were comparable. Differences between the genetics existed concerning the higher GP activities 1 min p.m. and the lower PFK activities 1 min and 40 min p.m. in the meat of the PiPP pigs. The investigation shows that the examined enzymes are involved in the meat development, whereas only the GP seems to influence the altered meat quality of the PiPP pigs
Molecular changes in mitochondrial respiratory activity and metabolic enzyme activity in muscle of four pig breeds with distinct metabolic types
No full textSkeletal muscles are metabolically active and have market value in meat-producing farm animals. A better understanding of biological pathways affecting energy metabolism in skeletal muscle could advance the science of skeletal muscle. In this study, comparative pathway-focused gene expression profiling in conjunction with muscle fiber typing were analyzed in skeletal muscles from Duroc, Pietrain, and Duroc-Pietrain crossbred pigs. Each breed type displayed a distinct muscle fiber-type composition. Mitochondrial respiratory activity and glycolytic and oxidative enzyme activities were comparable among genotypes, except for significantly lower complex I activity in Pietrain pigs homozygous-positive for malignant hyperthermia syndrome. At the transcriptional level, lactate dehydrogenase B showed breed specificity, with significantly lower expression in Pietrain pigs homozygous-positive for malignant hyperthermia syndrome. A similar mRNA expression pattern was shown for several subunits of oxidative phosphorylation complexes, including complex I, complex II, complex IV, and ATP synthase. Significant correlations were observed between mRNA expression of genes in focused pathways and enzyme activities in a breed-dependent manner. Moreover, expression patterns of pathway-focused genes were well correlated with muscle fiber-type composition. These results stress the importance of regulation of transcriptional rate of genes related to oxidative and glycolytic pathways in the metabolic capacity of muscle fibers. Overall, the results further the breed-specific understanding of the molecular basis of metabolic enzyme activities, which directly impact meat quality.German Research Foundation (Deutsche Forschungsgemeinschaft, DFG
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Sulforaphane causes a major epigenetic repression of myostatin in porcine satellite cells
No full textSatellite cells function as skeletal muscle stem cells to support postnatal muscle growth and regeneration following injury or disease. There is great promise for the improvement of muscle performance in livestock and for the therapy of muscle pathologies in humans by the targeting of myostatin (MSTN) in this cell population. Human diet contains many histone deacetylase (HDAC) inhibitors, such as the bioactive component sulforaphane (SFN), whose epigenetic effects on MSTN gene in satellite cells are unknown. Therefore, we aimed to investigate the epigenetic influences of SFN on the MSTN gene in satellite cells. The present work provides the first evidence, which is distinct from the effects of trichostatin A (TSA), that SFN supplementation in vitro not only acts as a HDAC inhibitor but also as a DNA methyltransferase (DNMT) inhibitor in porcine satellite cells. Compared with TSA and 5-aza-2'-deoxycytidine (5-aza-dC), SFN treatment significantly represses MSTN expression, accompanied by strongly attenuated expression of negative feedback inhibitors of the MSTN signaling pathway. miRNAs targeting MSTN are not implicated in posttranscriptional regulation of MSTN. Nevertheless, a weakly enriched myoblast determination (MyoD) protein associated with diminished histone acetylation in the MyoD binding site located in the MSTN promoter region may contribute to the transcriptional repression of MSTN by SFN. These findings reveal a new mode of epigenetic repression of MSTN by the bioactive compound SFN. This novel pharmacological, biological activity of SFN in satellite cells may thus allow for the development of novel approaches to weaken the MSTN signaling pathway, both for therapies of human skeletal muscle disorders and for livestock production improvement
Author Correction: The cell cycle stage of bovine zygotes electroporated with CRISPR/Cas9-RNP affects frequency of Loss-of-heterozygosity editing events
No full textGenomic background and genetic relationships between boar taint and fertility traits in German Landrace and Large White
No full textDue to ethical reasons, surgical castration of young male piglets in their first week of life without anesthesia will be banned in Germany from 2021. Breeding against boar taint is already implemented in sire breeds of breeding organizations but in recent years a low demand made this trait economically less important. The objective of this study was to estimate heritabilities and genetic relationships between boar taint compounds androstenone and skatole and maternal/paternal reproduction traits in 4'924 Landrace (LR) and 4'299 Large White (LW) animals from nucleus populations. Additionally, genome wide association analysis (GWAS) was performed per trait and breed to detect SNP marker with possible pleiotropic effects that are associated with boar taint and fertility
Regulation of Nrf2 and NF-κB during lead toxicity in bovine granulosa cells
No full textLead (Pb), one of the pervasive and protracted environmental heavy metals, is believed to affect the female reproductive system in many species. The Nrf2 and NF-κB are the two key transcriptional factors regulating cellular redox status and response against stress and inflammation respectively, showing an interaction between each other. The aim of this study is to investigate the effect of Pb on bovine granulosa cells (GCs) and its association with the regulation of Nrf2 and NF-κB pathways. For this, bovine GCs were cultured in vitro and exposed to different doses of Pb for 2 h. Cellular response to Pb insult was investigated 24 h post treatment. Results showed that exposure of GCs to Pb-induced ROS accumulation and protein carbonylation. Additionally, GCs exhibited reduction in cell viability and decrease in the expression of cell proliferation marker genes (CCND2 and PCNA). This was accompanied by cell cycle arrest at G0/G1 phase. Moreover, Pb downregulated both Nrf2 and NF-κB and their downstream genes. Lead increased the expression of endoplasmic reticulum (ER) stress marker genes (GRP78 and CHOP) and the proapoptotic gene (caspase-3) while the antiapoptotic gene (BCL-2) was reduced. Our findings suggest that Pb-driven oxidative stress affected GCs proliferation, enhances ER stress, induces cell cycle arrest and mediates apoptosis probably via disruption of Nrf2/NF-κB cross-talk. However, further functional analysis is required to explain different aspects of Nrf2 and NF-κB interactions under metal challenge
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