• Asian-Australasian Journal of Animal Sciences
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• v.33 no.5
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• pp.704-711
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• 2020

Objective: Muscle fiber types, numbers and area are crucial aspects associated with meat production and quality. However, there are few studies of pig muscle fibre traits in terms of the detection power, false discovery rate and confidence interval precision of whole-genome quantitative trait loci (QTL). We had previously performed genome scanning for muscle fibre traits using 183 microsatellites and detected 8 significant QTLs in a White Duroc×Erhualian F₂ population. The confidence intervals of these QTLs ranged between 11 and 127 centimorgan (cM), which contained hundreds of genes and hampered the identification of QTLs. A whole-genome sequence imputation of the population was used for fine mapping in this study. Methods: A whole-genome sequences association study was performed in the F₂ population. Genotyping was performed for 1,020 individuals (19 F₀, 68 F₁, and 933 F₂). The whole-genome variants were imputed and 21,624,800 single nucleotide polymorphisms (SNPs) were identified and examined for associations to 11 longissimus dorsi muscle fiber traits. Results: A total of 3,201 significant SNPs comprising 7 novel QTLs showing associations with the relative area of fiber type I (I_RA), the fiber number per square centimeter (FN) and the total fiber number (TFN). Moreover, one QTL on pig chromosome 14 was found to affect both FN and TFN. Furthermore, four plausible candidate genes associated with FN (kinase non-catalytic C-lobe domain containing [KNDC1]), TFN (KNDC1), and I_RA (solute carrier family 36 member 4, contactin associated protein like 5, and glutamate metabotropic receptor 8) were identified. Conclusion: An efficient and powerful imputation-based association approach was utilized to identify genes potentially associated with muscle fiber traits. These identified genes and SNPs could be explored to improve meat production and quality via marker-assisted selection in pigs.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2002.05a
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• pp.17-25
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• 2002

Application of electrical stimulation in the red meat species (eg. beef and sheep) processing has been erratic around the world and this may reflect an incomplete knowledge of how to optimise the technology. Although it is well established that stimulation increases the rate of post-mortem glycolysis other biochemical and biophysical effects have been implicated with the use of this technology. On the basis of currently available knowledge, this mini-review seeks to examine the current theories about the effect of stimulation on post-mortem muscle. The classical view that stimulation prevents muscle from shortening excessively during rigor development has been expanded to include the possibility that it also results in physical disruption of muscle structure. The interaction of these effects with the acceleration of the rate of proteolysis through activation of the calpain protease system has not been comprehensively reviewed in the past. As a result of conclusion driven, this article highlights several areas that may prove fruitful for further research. The challenge for further development of electrical stimulation systems is optimisation of the activation of the enzyme systems in parallel with manipulation of chilling regimes so as to ensure rigor mortis is achieved at temperatures which minimise shortening. The potential of regional stimulation of sections of the carcass to achieve this outcome is worthy of study given the different fibre composition of muscles and temperature gradients.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.137-146
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• 1982

Histological study of eel was carried out to determine the effect of drying on muscular tissue and fat movement. The results are as follows: (1) Changes of muscular tissue during drying may he divided into two stages early and late. In the early stage there was apparent dehydration of connective tissue while in the late stage muscle fibre dehydration appears to occur. (2) Movement of fat during drying depends upon division and contraction of the myocommata caused by inner structural changes. This phenomenon appeared to be more apparent in the late rather than the early drying stage.(3) After freeze-drying traces of ice crystals were detected around the muscle cells. These ice crystals remained even after rehydration. (4) When muscular tissue was heated the connective tissue melted while muscle fiber dehydrated and solidified.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8053-8058
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• 2016

Metformin is known as a hypoglycaemic agent that regulates glucose homeostasis by inhibiting liver glucose production and increasing muscle glucose uptake. Colorectal cancer (CRC) is one of the most common cancers worldwide, with about a million new cases diagnosed each year. The risk factors for CRC include advanced age, smoking, black race, obesity, low fibre diet, insulin resistance, and the metabolic syndrome. We have searched Medline for the metabolic syndrome and its relation to CRC, and metformin as a potential treatment of colorectal cancer. Administration of metformin alone or in combination with chemotherapy has been shown to suppress CRC. The mechanism that explains how insulin resistance is associated with CRC is complex and not fully understood. In this review we have summarised studies which showed an association with the metabolic syndrome as well as studies which tackled metformin as a potential treatment of CRC. In addition, we have also provided a summary of how metformin at the cellular level can induce changes that suppress the activity of cancer cells.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.12
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• pp.1764-1772
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• 2017

Objective: This study investigated the effects of different dietary energy sources on early postmortem muscle metabolism of finishing pigs. Methods: Seventy-two barrow ($Duroc{\times}Landrace{\times}Yorkshire$, DLY) pigs ($65.0{\pm}2.0kg$) were allotted to three iso-energetic and iso-nitrogenous diets: A (44.1% starch, 5.9% crude fat, and 12.6% neutral detergent fibre [NDF]), B (37.6% starch, 9.5% crude fat, and 15.4% NDF) or C (30.9% starch, 14.3% crude fat, and 17.8% NDF). After the duration of 28-day feeding experiment, 24 pigs (eight per treatment) were slaughtered and the M. longissimus lumborum (LL) samples at 45 min postmortem were collected. Results: Compared with diet A, diet C resulted in greater adenosine triphosphate and decreased phosphocreatine (PCr) concentrations, greater activity of creatine kinase and reduced percentage bound activities of hexokinase (HK), and pyruvate kinase (PK) in LL muscles (p<0.05). Moreover, diet C decreased the phosphor-AKT level and increased the hydroxy-hypoxia-inducible $factor-1{\alpha}$ ($HIF-1{\alpha}$) level, as well as decreased the bound protein expressions of HK II, PKM2, and lactate dehydrogenase A (p<0.05). Conclusion: Diet C with the lowest level of starch and the highest levels of fat and NDF could enhance the PCr utilization and attenuate glycolysis early postmortem in LL muscle of finishing pigs.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.1
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• pp.26-33
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• 2002

In order to assess the effect of feeding raw or processed cotton (Gossypium) seed meal (CSM) on meat and wool production, 30 male crossbred lambs (3-4 months) of uniform body weight were assigned equally to five dietary treatments in a completely randomised design. The CSM was processed by three different methods i.e., cooking the meal at $100^{\circ}C$ for 45 minutes, treatment with 1% calcium hydroxide ($Ca(OH)_2$) for 24 h and iron treatment in the ratio of 1 part free gossypol (FG) to 0.3 parts of iron for 30 minutes. The lambs were fed isonitrogenous and isocaloric concentrate mixtures, containing 30% deoiled peanut meal (reference diet) and 40% of either raw, cooked, $Ca(OH)_2$ or iron treated CSM for 180 days. The raw and variously processed CSM replaced about 50% nitrogen of reference concentrate mixture. The concentrate mixtures were fed to meet 80% of the protein requirements (NRC, 1985) along with ad libitum chopped maize (Zea mays) hay. The slaughter weight, empty body weight and carcass weight was higher ($p{\leq}0.01$) in lambs fed cooked CSM incorporated diets, compared to diets containing deoiled peanut meal (DPNM). These parameters were not influenced by feeding diets containing either raw, $Ca(OH)_2$ or iron treated CSM in comparison DPNM diets. The carcass length, loin eye area and edible and inedible portion of carcass and the meat: bone ratio in whole carcass were also not affected by feeding CSM based diets. Among various primal cuts, the yield of legs was lower ($p{\leq}0.05$) from raw CSM fed lambs in comparison to DPNM fed lambs. The fat content in the Longissimus dorsi muscle was reduced ($p{\leq}0.05$) in lambs fed processed CSM based diets compared to those fed DPNM diet. Replacing DPNM with either raw or processed CSM based diets did not influence the sensory attributes and overall acceptability of meat. The wool yield was higher ($p{\leq}0.05$) in iron treated CSM fed lambs. The fibre length and fibre diameter were comparable among lambs on various dietary regimes. Among lambs fed variously processed CSM diets, the feed cost per kg of edible meat production was lower ($p{\leq}0.05$) on $Ca(OH)_2$ treated CSM, followed by cooked CSM diet and then on raw CSM based diets compared to DPNM diet. The CSM after 1% $Ca(OH)_2$ treatment or cooking for 45 minutes appears to be a satisfactory protein supplement in lamb diets for meat and wool production to replace at least 50% nitrogen of scarce and costly peanut meal.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.80-84
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• 2005

An experiment was conducted to study the performance, carcass traits, serum lipid profile and immune competence in commercial broilers (2 to 42 d of age) fed graded levels (25, 50, 75 and 100%) of finger millet (FM) (Elusine coracana) in place (w/w) of yellow maize (YM). Each diet was fed to eight replicates (five female Vencobb broilers/replicate) housed in stainless steel battery brooders. The estimated metabolizable energy content of FM was about 540 kcal less than the YM. FM contained more protein (10.42 vs. 9.05%) and fibre (9.52 vs. 2.24%) compared to YM. Body weight gain, ready to cook yield, relative weights of giblet, liver, intestine and length of intestine at 42 d of age was not affected due to replacing YM with FM. But, the feed efficiency decreased in broilers fed diets containing 75 and 100% FM in place of YM at both 21 and 42 d of age. The amount of fat deposited in abdominal area decreased and the relative weight of gizzard increased with increase in level of FM in the diet. The serum HDL cholesterol at 21 and 42 d of age and serum triglycerides at 42 d of age decreased with increase in level of FM in diet. The relative weight of spleen and antibody titers against sheep red blood cells (SRBC) at 5 d post inoculation (PI) decreased in broilers fed FM at 100% of YM. However, the relative weight of bursa, SRBC titers at 10 d PI, antibody titers against ND virus and mortality were not affected due to incorporation of FM in place of YM in diet. The fat content in thigh muscle and liver decreased, while the protein content in these tissues increased with increase in the level of FM in broiler diet. Based on the results, it may be concluded that YM can be replaced with FM up to 25% on weight basis without affecting weight gain, carcass yields and immunity in commercial broiler diet (up to 42 d of age). Further, inclusion of finger millet reduced the fat deposition in thigh muscle, liver and in abdominal area compared to those fed maize as the principal source of energy.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.2
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• pp.217-223
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• 2006

Fifty castrated crossbred ($Landrace{\times}Yorkshire$) pigs, weighing an average of $60.6{\pm}3.1kg$ were allotted to one of five treatments in a randomized block design to examine the effects of dietary inclusion of 0.1% L-carnitine (50 ppm carnitine), 0.1% selenium-enriched yeast (0.3 ppm selenium), 0.1% Jujube fruit or 0.1% Hwangto (Red clay) on pig performance and carcass quality. All diets were based on corn, wheat, soybean meal and wheat bran and were formulated to supply 13.8 MJ DE/kg. Dietary supplementation did not influence daily gain (p = 0.57), feed intake (p = 0.52), or feed conversion (p = 0.32). Digestibility of dry matter (p = 0.60), organic matter (p = 0.74), crude protein (p = 0.76), crude fibre (p = 0.70) and energy (p = 0.75) were also unaffected by inclusion of any of the additives. Tissue samples taken from the longissimus muscle showed that the levels of carnitine (p = 0.0001) and selenium (p = 0.0001) were significantly higher with dietary inclusion of carnitine or selenium-enriched yeast. Dietary treatment did not affect dressing percentage (p = 0.33), carcass lean yield (p = 0.99) or first, $10^{th}$ and last rib midline backfat depth (p = 0.45, 0.82 and 0.47, respectively). Dietary treatment also did not affect the percentages of tenderloin (p = 0.37), bacon (p = 0.36), fat and bone (p = 0.56), picnic shoulder (p = 0.25), skirt (p = 0.80), fresh ham (p = 0.31) or ribs (p = 0.79). However, pigs fed the diet containing Jujube fruit had a higher percentage of Boston butt than pigs fed the carnitine or selenium supplemented diets (p = 0.01). Pigs fed added Hwangto had a higher (p = 0.04) percentage of loin compared with pigs fed supplementary selenium or Jujube fruit. Loin muscle from pigs fed carnitine had a significantly lower Hunter colour value for L (whiteness, p = 0.004) and a higher value for $a^*$ (redness; p = 0.069). The overall results indicate that supplementation with L-carnitine and selenium-enriched yeast can produce pork containing higher levels of carnitine and selenium, which could provide health benefits for consumers of pork without detrimental effects on pig performance.

• Animal Bioscience
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• v.35 no.8
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• pp.1223-1234
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• 2022

Objective: The objectives of this study were to evaluate the effects of daily feed intake during the laying period on embryonic myogenic differentiation 1 (MYOD1), myogenic factor 5 (MYF5), and myogenic factor 6 (MYF6) gene expression in genetically fat and lean lines of chickens. Methods: An experiment in a 2×2 factorial design was conducted with two dietary intake levels (100% and 75% of nutrition recommendation) and two broiler chicken lines (fat and lean). Two lines of hens (n = 384 for each line) at 23th week of age were randomly divided into 4 treatments with 12 replicates of 16 birds. The experiment started at 27th week of age (5% egg rate) and ended at 54th week of age. Hatched eggs from the medium laying period were collected. Real time polymerase chain reaction analysis was used to analyse the MYOD1, MYF5, and MYF6 mRNA levels of E7, E9, E11, E13, and E15 body tissues and E17, E19, and E21 chest and thigh muscle samples. Results: The results indicated that there were significant effects of line, dietary intake, and interactions between them on MYOD1, MYF5, and MYF6 gene mRNA expression levels in embryonic tissues. Low daily feed intake did not change the expression trend of MYOD1 mRNA in either line, but changed the peak values, especially in lean line. Low daily feed intake altered the trend in MYF5 mRNA expression level in both lines and apparently delayed its onset. There was no apparent effect of low daily feed intake on the trends of MYF6 mRNA expression levels in either line, but it significantly changed the values on many embryonic days. Conclusion: Maternal nutrient restriction affects myogenesis and is manifested in the expression of embryonic MYOD1, MYF5, and MYF6 genes. Long term selection for fat deposition in broiler chickens changes the pattern and intensity of myogenesis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.1
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• pp.15-27
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• 1974

Since the summer of the year 1972 ulcer disease of common carp, colour carp ana goldfish had suddenly spread widely and caused a serious mortality at fish farms especially around Gim-hae and Yang-san, near Busan. The present study aimed to find out the causative organisms, histopathological changes and the way of treatment, and the results are summarized as follows : Two kinds of pathogenic bacteria, i. e, Chondrococcus columnaris and Aeromonas sp. were isolated from the mucus of the lesion. According to the macroscopic findings, these symptoms began with the hemorrhagic spots under scales which fell out, after the collapse of the dermis, which was followed by lesion to form ulcer, and then the muscle was exposed. The fin was eroded mostly from the distal part, but sometimes from the basal part. Gills showed grey colour, and this part of the tissue collapsed. According to the histopathological findings, the dermis was exposed after the collapsed of the epithelium of the skin, and the necrosis of the musculature occurred, the muscular fibre being destroyed. The epithelial cells of gill tissue proliferated, thus gill filaments were conglutinated and collapsed. Fatty degeneration happened at the liver but the other organs seem to be normal. Treatment with the following mixtures were effective the water temperature of $22\~25^{\circ}C$, but not effective when the temperature was under as low as $13\~15^{\circ}C$. Mixture 1. Aivet (HB-115.HCI) 0.3ppm Malachite green 0.2ppm. Dipterex 0.4ppm Mixture 2. Furanace (P-7138) 0.05ppm Malachite green 0.2ppm Dipterex 0.4ppm When lesion healed, the epithelium, dermis, and the muscular fibre were regenerated.