Multidimensional assessment of meat quality across anatomical regions of Kazakh horses: an integrative evaluation of meat quality traits, amino acid profiles, and fatty acid composition

Branched-chain amino acids (BCAA), including leucine (Leu), isoleucine (Ile), and valine (Val), play critical roles in energy homeostasis and lipid metabolism in addition to their other functions, such as in protein metabolism. This study investigated the effects of different dietary BCAA ratios on the intramuscular fat (IMF) content and fatty acid composition in different location of skeletal muscles, including the longissimus dorsi (LD), biceps femoris (BF), and psoas major (PM) muscles of growing pigs, and also examined the mRNA expression levels of genes involved in lipid metabolism in these muscle tissues. The experiment was performed on 40 growing pigs (Large White×Landrace) with a similar initial weight (9.85±0.35kg). The pigs were randomly assigned to one of five diets: diet A was a positive control and contained 20% crude protein (CP) with a Leu:Ile:Val ratio of 1:0.51:0.63 according to the recommendation of the National Research Council (NRC); for diets B to E, the CP level was reduced to 17%, and the Leu:Ile:Val ratios were 1:1:1, 1:0.75:0.75, 1:0.51:0.63, and 1:0.25:0.25, respectively. No significant difference was observed in the average feed intake and feed efficiency of the pigs fed the low protein diet (17% CP) with BCAA treatments relative to the positive control. However, there was a tendency for increased feed efficiency of the 1:0.75:0.75 group compared with the 1:1:1 group (P=0.09). The BCAA ratio of 1:0.75:0.75 (17% CP) increased the IMF content of BF muscle (P<0.01). Moreover, varied dietary BCAA supplementation with a reduced protein level had different effects on the fatty acid composition of the LD, BF, and PM muscles. The BCAA ratio of 1:0.51:0.63-1:0.75:0.75 (17% CP) significantly lowered the ratio of n-6 to n-3 polyunsaturated fatty acid in these muscles compared with the positive control group (20% CP). This effect was associated with an increase in mRNA expression levels of acetyl-CoA carboxylase, lipoprotein lipase, fatty acid transport protein, and fatty acid binding protein 4 in the muscles (P<0.05). The results indicated that the reduced protein diet (17% CP) with the BCAA ratio within 1:0.25:0.25-1:0.75:0.75 could increase the IMF content in BF muscle and significantly improve the fatty acid composition in different skeletal muscles accompanied by changes in the expression of genes involved in lipid metabolism, compared with those in the pigs that received adequate dietary protein (20%), which might result in improved eating quality and nutritional value of the meat.

Shear values of raw samples of 14 bovine muscles and their relation to muscle collagen characteristics

Influence of diet on serum glucose and insulin concentrations, insulin receptor concentration in adipose and muscle tissues, and oxygen consumption in liver and muscle in gilts

Skeletal muscles are characterized as fast and slow muscles, according to the expression pattern of myosin heavy chain (MyHC) isoforms in the muscle fibers. To investigate the relationships between MyHC isoforms and myogenic regulatory factors (MRFs) including MyoD, Myf5, myogenin, and MRF4 in adult skeletal muscles, expressions of these MRFs in the ten muscles of three cows were analyzed by a semi-quantitative RT-PCR. The results showed that MyoD expression was significantly lower in the lingual muscles (TN), masseter (MS) and diaphragm (DP), which lack MyHC-2x (fast glycolytic) expression and abound with MyHC-slow (slow oxidative) and/or MyHC-2a (fast oxidative), than it was in the pectoralis (PP), psoas major (PM), longissimus thoracis (LT), spinnalis (SP), semitendinosus (ST), semimembranosus (SM), and biceps femoris (BF). In contrast, the Myf5 expression in TN, MS, and DP was significantly higher than in PM, LT, ST, SM, and BF. No significant difference was observed in myogenin and MRF4 expression among the muscles tested. The results suggest that MyoD and Myf5 influence the MyHC isoform expression, although the effects are not decisive in specifying the phenotypes of adult muscles.

The objective of this study was to determine the extent of variation in, and relationships among, biochemical and palatability traits within and among 11 major beef muscles. Longissimus thoracis et lumborum (LD), psoas major (PM), gluteus medius (GM), semimembranosus (SM), adductor (AD), biceps femoris (BF), semitendinosus (ST), rectus femoris (RF), triceps brachii (TB), infraspinatus (IS), and supraspinatus (SS) from one side of 31 Charolais × MARC III steer carcasses were vacuum-packaged, stored at 2°C until 14 d postmortem, and then frozen at −30°C. The 2.54-cm-thick steaks were obtained from two or three locations within muscles in order to assess biochemical traits and Warner-Bratzler shear force, and from near the center for sensory trait evaluation. The PM was most tender and was followed by IS in both shear force and tenderness rating (P < 0.05). The other muscles were not ranked the same by shear force and tenderness rating. The BF had the lowest (P < 0.05) tenderness rating. The PM, GM, and LD had lower (P < 0.05) collagen concentration (2.7 to 4.5 mg/g muscle) than muscles from the chuck and round (5.9 to 9.0 mg/g), except for the AD (4.9 mg/g). Desmin proteolysis was highest (P < 0.05) for BF and LD (60.7 and 60.1% degraded), and was lowest (P < 0.05) for PM (20.2%). The PM, TB, IS, RF, and ST had relatively long sarcomere lengths (>2.1 μm), whereas the GM had the shortest (P < 0.05) sarcomere length (1.7 μm). Cooking loss was lowest (P < 0.05) for BF (18.7%) and was followed by LD and IS (20.7%); it was highest (P < 0.05) for ST (27.4%). Across all muscles, tenderness rating was highly correlated (r > 0.60) with shear force, connective tissue rating, sarcomere length, and collagen content. Within a muscle, correlations among all traits were generally highest in LD and lowest in AD. Within muscle, location effects were detected (P < 0.05) for shear force (PM, ST, BF, SM, and RF), sarcomere length (PM, ST, BF, LD, SS, IS, SM, and RF), collagen concentration (PM, BF, SS, IS, SM. AD, TB, and RF), desmin degradation (PM, GM, BF, SM, AD, and, RF), and cooking loss (all muscles except SS and AD). There is a large amount of variation within and among muscles for tenderness traits and tenderness-related biochemical traits. These results increase our understanding of the sources of variation in tenderness in different muscles and provide a basis for the development of muscle-specific strategies for improving the quality and value of muscles.

The objective of this study was to determine the extent of variation in, and relationships among, biochemical and palatability traits within and among 11 major beef muscles. Longissimus thoracis et lumborum (LD), psoas major (PM), gluteus medius (GM), semimembranosus (SM), adductor (AD), biceps femoris (BF), semitendinosus (ST), rectus femoris (RF), triceps brachii (TB), infraspinatus (IS), and supraspinatus (SS) from one side of 31 Charolais x MARC III steer carcasses were vacuum-packaged, stored at 2 degrees C until 14 d postmortem, and then frozen at -30 degrees C. The 2.54-cm-thick steaks were obtained from two or three locations within muscles in order to assess biochemical traits and Warner-Bratzler shear force, and from near the center for sensory trait evaluation. The PM was most tender and was followed by IS in both shear force and tenderness rating (P < 0.05). The other muscles were not ranked the same by shear force and tenderness rating. The BF had the lowest (P < 0.05) tenderness rating. The PM, GM, and LD had lower (P < 0.05) collagen concentration (2.7 to 4.5 mg/g muscle) than muscles from the chuck and round (5.9 to 9.0 mg/g), except for the AD (4.9 mg/g). Desmin proteolysis was highest (P < 0.05) for BF and LD (60.7 and 60.1% degraded), and was lowest (P < 0.05) for PM (20.2%). The PM, TB, IS, RF, and ST had relatively long sarcomere lengths (> 2.1 microm), whereas the GM had the shortest (P < 0.05) sarcomere length (1.7 microm). Cooking loss was lowest (P < 0.05) for BF (18.7%) and was followed by LD and IS (20.7%); it was highest (P < 0.05) for ST (27.4%). Across all muscles, tenderness rating was highly correlated (r > 0.60) with shear force, connective tissue rating, sarcomere length, and collagen content. Within a muscle, correlations among all traits were generally highest in LD and lowest in AD. Within muscle, location effects were detected (P < 0.05) for shear force (PM, ST, BF, SM, and RF), sarcomere length (PM, ST, BF, LD, SS, IS, SM, and RF), collagen concentration (PM, BF, SS, IS, SM. AD, TB, and RF), desmin degradation (PM, GM, BF, SM, AD, and, RF), and cooking loss (all muscles except SS and AD). There is a large amount of variation within and among muscles for tenderness traits and tenderness-related biochemical traits. These results increase our understanding of the sources of variation in tenderness in different muscles and provide a basis for the development of muscle-specific strategies for improving the quality and value of muscles.

The tropical legume Indigofera zollingeriana may be utilized as a ruminant ration base to optimize intramuscular polyunsaturated fatty acid (PUFA) composition in Kacang goat. The objective of this research was to investigate how diets incorporating I. zollingeriana affect the fatty acid composition in the Supraspinatus (SS), Longissimus dorsi (LD), and Biceps femoris (BF) muscle tissue of Kacang goats. In this study, 16 male goats were prepared and arranged using a completely randomized design. The treatments were CON, IZ60, IZ75, and IZ90, containing 0%, 60%, 75%, and 90% I. zollingeriana, respectively. The goats were slaughtered after 84 days of rearing, and samples were collected from the SS, LD, and BF muscles. SS muscle had the highest PUFA content (37%), while the lowest thrombogenicity index (TI) and cholesterol of 0.68 and 55.38 g/100g respectively were found in the IZ90 treatment. In the LD muscle, the highest PUFA content (31.29%) and PUFA/SFA ratio (0.82) were found in the IZ75 treatment, while the TI value was 0.94. Moreover, in the BF muscle, the highest PUFA content (30.84%) was found in the IZ75 treatment with a fat content of 0.20%. The CON, IZ75, and IZ90 treatments resulted in similar fatty acid profiles in BF and LD muscles. The inclusion of I. zollingeriana in the diet of Kacang goats can effectively increase the levels of total PUFA in muscle tissue. These findings suggest that I. zollingeriana can serve as a valuable feed source to enhance the nutritional quality of goat meat by improving its fatty acid profile.

The aim of this study was to evaluate the effect of three levels of feed intake (1.5%, 2% or 2.5% of body weight) and individual muscle on quality and histochemical parameters of 10 dromedary camel (1–2 year-old). Meat quality including ultimate muscle pH, Warner-Bratzler shear force, sarcomere length, myofibrillar fragmentation index, expressed juice, cooking loss%, and colour L*, a*, b* were measured using standard methods. The histochemical staining properties of the myosin ATPase and succinate dehydrogenase stains were evaluated. The pH from the left side of Infraspinatus (IS), Triceps brachii (TB), Longissimus thoracis (LT), Biceps femoris (BF), Semitendinosus (ST) and Semimembranosus (SM) muscles was monitored using a portable pH meter at 1, 2, 4, 8, 12, 24 and 48 hr postmortem. Feeding level had no significant effect on the initial muscle pH or rate of pH decline or muscle fibre type or meat quality characteristics. However, type of muscle had a significant effect on quality and muscle fibre type proportion and diameter. The LT muscle had the highest cooking loss (33.7%) and TB muscle had the lowest (28.8%). The Shear force values of ST (9.3 kg), SM (10.5 kg) and BF (9.9 kg) muscles were significantly higher than LT (5.7 kg) and IS (6.68 kg) muscles. The LT muscle had significantly higher values for L*, a*, b* than ST. The IS muscle had the highest myofibrillar fragmentation index (74.5), while BF muscle had the lowest value (63.0). The BF muscle had the highest proportion of Type I and the lowest proportion of Type IIA than other muscles. This study indicated that type of muscle had more effect than feeding level on quality characteristics of dromedary camel.

SUMMARY—This research was to determine whether quantitative differences in total pigment and myoglobin concentration could be detected, chemically, in muscles which differed in visual color. For this purpose, a portion of the longissimus dorsi, psoas major, biceps femoris, and semitendinosus muscles was removed at specific locations, from choice‐grade steer carcasses, for use as experimental material. Each muscle was subjected to total pigment, myoglobin, fat, and moisture analysis. Hemoglobin content was determined by the difference between total pigment and myoglobin concentrations, Correction of total pigment and myoglobin concentration for fat and/or moisture was used to determine its influence upon the variation in the quantity of muscle pigmentation.Precise results were obtained with the total pigment and myoglobin procedures. Total pigment concentration was greatest in the biceps femoris and least in the semitendinosus. Little difference was obtained between the longissimus dorsi and psoas major. Myoglobin concentration, in decreasing order of magnitude, for the muscles studied was biceps femoris, longissimus dorsi, psoas major, and semitendinosus. The difference between myoglobin and total pigment concentration in the psoas major muscle was a result of hemoglobin constituting a greater portion of the total pigmentation. Results also indicated that hemoglobin contributed more to total pigment concentration and probably to muscle color than previously reported. The significance of the results obtained was not altered by correcting the data for fat and/or moisture.

Thermal transition of collagen in ovine connective tissues

Fatty acid composition of water buffalo meat

Changing fatty acid composition is a potential nutritional strategy to shape microbial communities in pigs. However, the effect of different n-6/n-3 polyunsaturated fatty acid (PUFA) ratios on serum fatty acid composition, microbiota, and their metabolites in the intestine of pigs remains unclear. Our study investigated the changes in serum fatty acid composition and metabolome–microbiome responses induced by dietary n-6/n-3 PUFA ratio based on a Heigai-pig model. A total of 54 Heigai finishing pigs (body weight: 71.59 ± 2.16 kg) fed with 3 types of diets (n-6/n-3 PUFA ratios are 8:1, 5:1, and 3:1) were randomly divided into 3 treatments with 6 replications (3 pigs per replication) for 75 days. Results showed that dietary n-6/n-3 PUFA ratio significantly affected biochemical immune indexes including glucose (Glu), triglycerides (TG), total cholesterol (TChol), non-esterified fatty acid (NEFA), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total thyroxine (TT4), and medium- and long-chain fatty acid composition, especially n-3 PUFA and n-6/n-3 PUFA ratio in the serum. However, no significant effects were found in the SCFAs composition and overall composition of the gut microbiota community. In the low dietary n-6/n-3 PUFA ratio group, the relative abundance of Cellulosilyticum, Bacteroides, and Alloprevotella decreased, Slackia and Sporobacter increased. Based on the metabolomic analysis, dietary n-6/n-3 PUFA ratio altered the metabolome profiles in the colon. Moreover, Pearson’s correlation analysis indicated that differential microbial genera and metabolites induced by different n-6/n-3 PUFA ratio had tight correlations and were correlated with the n-6 PUFA and n-3 PUFA content in longissimus dorsi muscle (LDM) and subcutaneous adipose tissue (SAT). Taken together, these results showed that lower dietary n-6/n-3 PUFA ratio improved serum fatty acid composition and metabolome–microbiome responses of Heigai pigs and may provide a new insight into regulating the metabolism of pigs and further better understanding the crosstalk with host and microbes in pigs.

ABSTRACTMyofibrils isolated from bovine longissimus (L), semitendinosus (ST) and psoas major (PM) muscles at‐death and at 1, 2, 3, 6 and 10 days postmortem storage (2 and 25°C) were analyzed with sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis. One of the subunits of troponin, troponin T, disappeared from L and ST muscle during postmortem storage at 25°C, and concurrently a 30,000 dalton component appeared. Storage of muscles at 25°C accelerated these changes in myofibrils from L and ST muscles, but SDS polyacrylamide gels of PM muscle changed little during storage at either 2 or 25°C. Crude preparations of a Ca2+‐activated factor (CAF) were isolated from bovine L, ST and PM muscles. Total CAF activity was high and similar in L and ST muscles, but PM muscle contained less than half the total CAF activity of L and ST muscles. Incubation of purified CAF with myofibrils isolated from at‐death muscle caused Z‐disk degradation and disappearance of troponin T and the simulataneous appearance of a 30,000 dalton component. That incubation of purified CAF with purified troponin caused degradation of troponin‐T to a 30,000‐dalton component indicates that the 30,000‐dalton component in whole myotibrils originates from troponin‐T. The effects of CAF on Z‐disk and troponin‐T degradation and the relative total activity of CAF in L, ST and PM muscles are similar to the effects of postmortem storage in myofibril fragmentation, myotibrillar protein degradation and WB shear force values. These parallel effects indicate that the limited and. specific proteolysis of myofibrillar proteins is caused by a Ca2+‐activated factor endogenous to the muscle cell.

Influence of type of muscles on nutritional value of foal meat

Mutton is one of the most popular meats among the public due to its high nutritional value. In this study, we compared and analyzed the nutritional composition and volatile flavor substances in longissimus dorsi (LD), psoas major (PM), and biceps femoris (BF) of the Chaka sheep, and then analyzed the lipid composition using the technique of UHPLC-Q-Exactive Orbitrap MS/MS. Our results indicated that the LD had the highest crude protein content (22.63%), the highest levels of aspartic acid (5.72%) and histidine (2.76%), the BF had the highest contents of glycine (3.40%) and proline (2.88%), the PM had the highest abundance of ω-6 polyunsaturated fatty acids (7.06%), linoleic acid (C18:2n6c; 5.03%), and volatile flavor compounds (alcohols, ketones, and esters). Moreover, our study detected 2,639 lipid molecules classified into 42 classes, among which phospholipids were the major lipids, accounting for nearly half of the total lipids. Among them, phosphatidylethanolamine (PE; 18:2/18:2) and phosphatidylcholine (PC; 25:0/11:3) were the characteristic lipids in LD. Phosphatidylserine (PS; 20:3e/20:4), lysophosphatidylcholine (LPC; 18:3), PE (8:1e/12:3), triacylglycerol (TG; 18:0e/16:0/18:1), TG (18:0/18:0/18:0), TG (18:0e/18:0/18:1), and TG (18:0e/18:1/18:1) were marker lipids in PM. LPC (16:0), LPC (18:1), lysophosphatidylethanolamine (18:1), PC (15:0/22:6), PE (18:1/18:1), Hex1Cer (d24:1/18:1), and PC (10:0e/6:0) were representative lipids in BF. Intermolecular correlations between PC, PE, Hex1Cer, PS, TG, diacylglycerol, and cardiolipid were revealed by correlation analysis. In conclusion, this study provided the interpretation of the specific nutritional indicators and lipid profile in the tripartite muscle of Chaka sheep, which can be used as a guidance for future research on the nutritional qualities and economic benefits of mutton.