Improve Meat Quality Research Articles

Ablation of LKB1 gene changes the lipid profiles of goat intramuscular fat and enhances polyunsaturated fatty acids deposition

The content and composition of intramuscular fat (IMF) affect the cooked meat palatability such as tenderness and juiciness. Thus, elucidation of lipid deposition and its composition in goat IMF is necessary. Here, Jianzhou big-ear goats with higher IMF content is associated with lower mRNA level of LKB1 gene, compared with those of Chuannan black goats. Functionally, knockdown of LKB1 promoted intramuscular adipocyte lipid accumulation. Next, LC-MS/MS based pseudo target analysis found that 409 lipids existed in goat intramuscular adipocytes, of which polyunsaturated fatty acids accounted for most lipids. Compared with the control, 78 differential lipids were screened in the siLKB1 group, enriched in the triacylglycerols and fatty acids subclasses. The combined analysis between lipidomic and published transcriptomic data showed that siLKB1 enhanced polyunsaturated fatty acids synthesis through upregulation expression of HACD4. Finally, the promotion of lipid accumulation and polyunsaturated fatty acids synthesis in the LKB1 knockdown cells were partly rescued by ablation of HACD4. Collectively, these data provide a genetic target to produce PUFA enriched functional goat meat and expand new insights into improvement of meat quality.

Insight into the chemical composition, antioxidant capacity, meat quality, fatty acid profile, and volatile compounds of yellow-feathered chickens fed with fermented pineapple residue

This study aimed to evaluated the effect of dietary fermented pineapple residue (FPR) on chemical composition, antioxidant capacity, meat quality, fatty acid profile, and volatile compounds in yellow-feathered chickens. GC-IMS technique combined with multivariate analysis were performed to clarify the key volatile compounds. The results showed that dietary FPR improved meat quality by increasing the antioxidant capacity, pH value, and decreasing cooking loss of breast muscle. The fatty acids profile was altered in breast muscle of chickens that fed with FPR. GC-IMS detected 43 volatile compounds in breast muscle, including mainly aldehydes, esters, and alcohols. Among them, 12 volatile compounds could serve as potential aroma markers to distinguish meat flavor of chickens fed with FPR. Correlation analysis revealed that C18:1n9c, C18:2n6, and PUFA are important contributor for meat flavor formation. In conclusion, dietary FPR improved antioxidant capacity, meat quality, fatty acids profile, and volatile compounds of breast muscle in chickens.

Application of an attention bias test after surgical castration in piglets

Surgical castration of male piglets is a routine procedure performed to improve meat quality. Prior studies have shown that pain due to castration can last for up to 4 days, negatively impacting animal welfare, however the impact on affect, such as anxiety, is unclear. The objective of this study was to test the application of a novel attention bias test to assess anxiety in piglets that underwent surgical castration with or without practical pain alleviation methods. Piglets were surgically castrated (n = 22), castrated with analgesics (n = 21), or sham-handled (n = 22) at 3 days of age. An attention bias test was performed in week 1 (n = 32, 10–11/treatment) and 12 (n = 29, 9–10/treatment) to assess anxiety (an affective state), with feed (positive stimulus), loud bangs, and flashing lights (negative stimuli) presented simultaneously. Latency to visit the feeder, behavioral responses, and activity were recorded during the test. Additional data on piglets’ activity, tails, and grimaces were collected at three timepoints, at 1, 6, and 24 h after castration to determine pain experience. Piglets’ increased activity (P = 0.065), the fact that fewer piglets visited the feeder (P = 0.029), and tended to have longer latencies to visit the feeder (P = 0.092) in the attention bias test in week 1 might suggest that pain caused by surgical castration increased anxiety. No differences were detected in week 12. Castration treatment and sampling timepoint impacted activity levels hours after treatments, however, other measures were not impacted. These results suggest that more research is needed to determine how affect is impacted by pain caused by surgical castration. Activity and behavioral results somewhat support previous findings that surgical castration causes pain in piglets. As this is the first study assessing the relationship between painful procedures and piglet anxiety, more research is needed to determine a valid method to understand the impacts of these procedures on pig affect.

Comparison of High n-3 PUFA Levels and Cyclic Heat Stress Effects on Carcass Characteristics, Meat Quality, and Oxidative Stability of Breast Meat of Broilers Fed Low- and High-Antioxidant Diets.

This study investigated the individual and combined effects of a high dietary n-3 PUFA intake and cyclic heat stress (HS) on the carcass characteristics, meat quality, and oxidative stability of broiler breast meat and the potential of antioxidant supplementation (vitamins E, C, and selenium) to mitigate these effects. A total of 192 one-day-old male Ross 308 broilers were randomly assigned to 24 pens within two controlled environment chambers and fed with the following diets: a basal diet low in antioxidants according to NRC recommendations (NRC group), a basal diet according to Aviagen recommendations additionally supplemented with 200 IU/kg vitamin E, 250 mg/kg vitamin C, and 0.15 mg/kg selenium (HAOX group), and these two diets further supplemented with 5% linseed oil (NRC N-3 and HAOX N-3 groups). On day 22, the broilers were exposed to the following two environmental conditions: thermoneutral (TN, 21 °C) or cyclic HS (HS, 34 ± 1 °C, 7 h/d) in a 2 × 2 × 2 factorial design. A high intake of n-3 PUFAs significantly decreased growth performance, dressing percentage, and breast yield, while the incidence of pale, soft, and exudative (PSE) meat characteristics and malondialdehyde (MDA) levels increased. Cyclic HS reduced body weight (BW) and average daily feed intake (ADFI), but had limited effects on meat quality. No interactions between n-3 PUFAs and HS were observed for any measurements. High antioxidant supplementation increased breast yield, improved meat quality, and reduced oxidative stress, as evidenced by an enhanced antioxidant activity and lower MDA levels. In conclusion, n-3 PUFAs had a negative effect on both the carcass characteristics and meat quality of broilers, while HS primarily affected only carcass characteristics, with neither stressor having severe adverse effects. High levels of antioxidants could mitigate the negative effects of dietary- and heat-induced oxidative stress by enhancing the oxidative stability of broiler meat.

CircARID1A Inhibits Tail Fat Cell Differentiation in Guangling Large-Tailed Sheep by Regulating the miR-493-3p/YTHDF2 Axis.

The Guangling Large-Tailed sheep is renowned for its unique tail fat deposition, with a significant proportion of its total body fat being localized in the tail region. Fat deposition is a complex biological process regulated by various molecular mechanisms. Our previous studies have identified a large number of differentially expressed circular RNAs (circRNAs) in the tail adipose tissue of the Guangling Large-Tailed sheep. These circRNAs may play a pivotal role in the process of fat deposition. Given the potential regulatory functions of circRNAs in adipose metabolism, investigating their roles in tail fat deposition is of significant scientific importance. In this study, we identified novel circARID1A. Using various experimental methods, including lentivirus infection, RNase R treatment, actinomycin D assay, qPCR, western blotting, and dual-luciferase reporter assays, we determined that circARID1A inhibits the expression of miR-493-3p through competitive binding, thereby regulating adipocyte differentiation. Further research revealed that miR-493-3p promotes adipocyte differentiation by targeting YTH domain family 2 (YTHDF2), and this regulatory effect is also influenced by circARID1A. In conclusion, our findings suggest that circARID1A inhibits tail fat cell differentiation in the Guangling Large-Tailed sheep through the circARID1A/miR-493-3p/YTHDF2 axis, providing theoretical support for improving meat quality and fat deposition in sheep.

Comparative performance of selected triploid oysters Crassostrea (Magallana) gigas, produced by chemical induction and mated triploid techniques, to their diploid counterparts

The partial sterility of triploid (3n) oysters enables year-round harvest, improved meat quality, and superior growth compared to diploids. Two main techniques are used to produce shellfish triploids: 1) the ‘chemical induction’ method, where the release of polar body 2 in embryos is blocked via chemical treatment and 2) the ‘mated triploid’ method, widely used, where tetraploid (4n) males are crossed with diploid females to produce all triploid offspring. There have been growing concerns however that mated triploids may be more vulnerable to diseases or climate-driven stressors.In this research the long-term performance of selectively bred 3n oysters [Crassostrea (Magallana) gigas] obtained using different induction methods was evaluated both in the laboratory and in the field to identify any potential trade-offs from each method. Using genetically related parental stock, one diploid control (2n) and triploids derived from chemical induction (3nC) or mated triploids (3nM) were produced in the hatchery and multiple performance indicators - including growth, survival, reproductive effort, and tolerance to environmental stressors (OsHV-1 and acute heat stress) - were assessed at key life stages.Chemical induction yielded 96.3 % triploid D-larvae compared to 100 % for the mated triploids. Larval performances (e.g., survival) of 3nM and 2n were comparable, whereas 3nC had lower spat yield than 3nM. Triploid larvae grew faster than their related 2n, with no advantage amongst 3n groups. Lab-based OsHV-1 infection of spat showed no advantages from any groups with high survival across ploidy, while acute heat-stress challenges of adults showed that 3nM were more thermotolerant than 2n and 3nC.Remaining oysters were then deployed to multiple grow-out sites and their survival and growth assessed periodically. Field-survival after 20 months was high (>80 % for all groups) across all sites, with 3nM being on average 17 % larger than 3nC, and 40 % larger than their 2n counterparts. Combined number of eggs produced by 3nC and 3nM females was significantly lower than that of all 2n females (i.e., 5.5 % of 2n); however, reproductive potential amongst triploids was generally higher in 3nM than 3nC, particularly in oysters grown in warmer waters. Collectively, these findings inform stakeholders in assessing the feasibility of using tetraploids or direct chemical induction for 3n oyster spat production.

Effects of aging and repeated freeze-thaw cycles on quality attributes, physicochemical and biochemical properties, and sensory characteristics of beef sirloins

This study aimed to evaluate the influence of aging before freezing and repeated freezing on quality attributes of beef sirloins. At 5 days postmortem, pairs of sirloins (M. gluteus medius) were collected from 20 beef carcasses (USDA Choice grade). The sirloin samples from each side were assigned to either no additional aging (A0) or 4 weeks of aging (A4). Samples were then subjected to either single freeze-thawing (A0FT and A4FT) or repeated freeze-thawing (A0FT × 2 and A4FT × 2) over 3 weeks. Following aging (2 °C), freezing (−20 °C), and thawing (2 °C), the samples were evaluated for water-holding capacity (WHC), Warner-Bratzler shear force (WBSF), myofibrillar fragmentation index (MFI), color, 2-thiobarbituric acid reactive substances (TBARS), carbonyl and thiol contents, and consumer sensory evaluation (n = 120). Freezing without aging increased freeze-thaw and drip losses in A0FT and A0FT × 2 compared to A4FT and A4FT × 2 (p < 0.05). Freezing and repeated freezing decreased WBSF values (p < 0.05) regardless of aging status. Similarly, MFI was higher in A0FT and A4FT compared to A0 and A4, respectively (p < 0.05). Both freezing and repeated freezing increased TBARS levels (p < 0.05). Moreover, freezing without aging reduced CIE L*, a*, b* and chroma values (p < 0.05). However, aged/frozen samples retained similar color attributes to never frozen counterparts (p > 0.05). Consumer sensory panel reported improved sensory attributes of aged/frozen samples, without any adverse effects from repeated freezing. These findings indicate that aging can improve WHC, color, and tenderness of single or repeated frozen/thawed beef sirloins, suggesting it as a practical strategy for the industry to improve meat quality and value of frozen/thawed beef.

Antibiotics and lectin C for diarrhea control intervention in piglets and influences

The study was conducted on 60 L of suckling piglets out of 775 piglets, of which 227 piglets had diarrhea litres of piglets, and out of 775 piglets, 227 piglets had diarrhoea syndrome. There were 3 interventions in separate trials as follows: 1 and 2 involved antibiotic use (Enrofloxacin and Gentamicin); Trial 3 used the supplement Lectin C (LvCLT3 and LvCLT4) for a treatment period of 3–7 days. Intervention results on 227 piglets with diarrhea showed the highest cure rate when supplemented with Lectin C, with no mortality rate, longer treatment time, and no reinfection rate. While the two antibiotic trials still had lower cure rates, mortality and reinfection rates were higher. After 05 days of recovery, piglets were tested for MCV, MCH, and MCHC, showing an apparent decrease in the group supplemented with Lectin C, while the two groups using antibiotics still had high rates, with a confidence level of P < 0.05; 0.01 and 0.001. Antibiotics treat piglets in their early stages, so there is a risk of immunodeficiency and low infection response. It is necessary to supplement substances derived from dietary supplements. Supplementing Lectin C increases resistance, enhances immune response, improves the effectiveness of treating diarrhoea syndrome in piglets, and ensures safe meat quality in the future. Lectin C supplementation will improve piglet health and breed quality efficiency. This heralds a promising future for the pig industry with improved meat quality and reduced environmental impact.

Initial Evaluation of Safety and Immunomodulatory Potential of Dietary Supplementation with Mangosteen Pericarp Extract for Sustainable Meat Production in Native Crossbred Chickens.

The utilization of mangosteen biomass not only solves environmental problems but also raises the value of agricultural waste. The current study aimed to evaluate the potential of mangosteen pericarp extract (MPE) for enhancing the immunity and productivity of Thai native crossbred chickens on-farm. A total of 180 three-week-old chickens were divided into negative control and supplemented groups, with 1000 mg MPE/kg of diet. The safety of MPE was further confirmed by the absence of noticeable differences in mortality and biochemical parameters during the entire study period. The MPE-supplemented group displayed significant differences in the relative transcription levels of IL-10 compared to the basal diet group (p ≤ 0.01). Preslaughter body weight, average daily gain, and carcass weight in the MPE-supplemented group were higher than those in the basal diet group (p ≤ 0.05). Furthermore, MPE supplementation improved meat quality by enhancing the nutritional composition of protein and fat (p ≤ 0.05), as well as improving water-holding capacity, lowering boiling, and lowering grilling losses (p ≤ 0.01). These findings indicate that MPE can be an effective supplement for enhancing flock immunity, growth performance, and meat quality in poultry. This contributes to more sustainable agriculture and food security within agroecosystems.

Beef Carcasses Aged at Mild Temperature to Improve Sustainability of Meat Production

Beef carcass aging, which enhances tenderness and flavor through proteolysis, is traditionally costly and slow, requiring long-term storage at temperatures near 0 °C. To reduce energy consumption, a new technique using moderate cooling room temperatures was tested. Six carcasses of Holstein bulls were used. From each carcass, two shoulders were processed in different ways: one was refrigerated at 8 °C (W), and after spraying with a solution with calcium chloride and sodium chloride, was coated with sodium alginate. The other shoulder was stored at 2 ± 1 °C as a cold control (C). After five days of aging, the shoulders were dissected, and two muscles (Caput longum triceps brachii and Supraspinatus) were subjected to physico-chemical analysis, microbiological safety assessment, and sensory testing. The remaining samples of both muscles were stored in domestic conditions for an additional 5 days at various temperatures (2, 4, 8 °C), where the same physic-chemical and sensory tests were conducted. The results showed that moderate aging temperature improved meat quality, significantly reducing the shear force (p = 0.001) and increasing sarcomere length, the myofibrillar fragmentation index, and sensory tenderness (p = 0.042, p = 0.039, and p = 0.027, respectively). However, domestic storage post-dissection should not exceed 4 °C to prevent rapid lipid oxidation, as observed at 8 °C for both muscles (p &lt; 0.001). Mild aging temperature maintained legal safety standards, enhanced certain meat qualities, and promoted enzymatic activity similar to traditional dry aging while reducing high energy consumption.

PPM1J regulates meat quality feature and glycerophospholipids composition in broiler by modulating protein dephosphorylation

The quality of broiler meat affects consumers’ purchasing decisions. Numerous studies have shown that phosphorylation of proteins in muscle can affect muscle quality. Here, metabolomics and transcriptomics were used to systematically identify the genetic regulation of differences in meat flavor among different broiler. By constructing the meat flavor-related metabolite-gene networks, we identified that protein phosphatase magnesium/manganese-dependent 1J (PPM1J), which is known to regulate a range of biological processes by modulating reversible protein phosphorylation, was a differentially expressed gene with the highest connectivity to meat flavor-related metabolites. Gain- and loss-of-function analysis revealed that PPM1J induced muscular atrophy, improved meat quality and regulated the composition of glycerophospholipids. More importantly, phosphoproteome and metabolome results found that PPM1J participates in the regulation of meat quality feature and glycerophospholipids composition by catalyzing protein dephosphorylation. Our study provides a basis for further understanding the molecular mechanism of meat quality feature and glycerophospholipids composition in broiler.

Glycogen Supplementation in Vitro Promotes pH Decline in Dark-Cutting Beef by Reverting Muscle's Metabolome toward a Normal Postmortem Muscle State.

Dysregulated muscle glycogen metabolism preslaughter contributes to aberrant postmortem muscle pH (>5.8) in dark-cutting beef phenotypes. However, the underlying mechanisms have remained elusive. Herein, we examine the glycogen dependent regulation of postmortem muscle pH decline and darkening in beef. We show that supplementation of glycogen in vitro restores postmortem pH decline in dark-cutting beef by reverting the metabolome toward a typical postmortem muscle state characterized by increased activities of enzymes glycogen phosphorylase and lactate dehydrogenase (p < 0.05) coupled with a pronounced abundance of glycolytic metabolites and reduced abundance of tricarboxylic acid cycle and amino acid metabolites. Furthermore, concurrent inhibition of mitochondrial respiration at complexes I, IV, and V with glycogen supplementation stimulates greater pH decline. Together, our findings show that supplementing glycogen at low concentrations (10 mM) can reprogram the dark-cutting beef muscle's metabolome toward typical postmortem state and promote muscle acidification. Thus, enhancing glycogen levels could represent a promising strategy for mitigating dark-cutting beef phenotypes and improving meat quality.

Effect of NR1D1 on the proliferation and differentiation of yak skeletal muscle satellite cells.

The severe conditions at high altitudes, where yaks inhabit, contribute to delayed muscular growth and compromised tenderness of their muscle tissue. Myosatellite cells are responsible for the growth and regeneration of skeletal muscle after birth and have the potential to proliferate and differentiate, its development is closely related to meat quality, and the nuclear receptor gene NR1D1 is involved in muscle formation and skeletal muscle regulation. Therefore, in order to understand the effect of NR1D1 on muscle satellite cells, we identified the mRNA expression levels of marker genes specifically expressed in muscle satellite cells at different stages to determine the type of cells isolated. Eventually, we successfully constructed a primary cell line of yak muscle satellite cells. Then we constructed NR1D1 overexpression vector and interference RNA, and introduced them into isolated yak skeletal muscle satellite cells. We performed qPCR, CCK8, and fluorescence-specific to detect the expression of genes or abundance of proteins as markers of cell proliferation and differentiation. Compared with those in the control group, the expression levels of proliferation marker genes KI-67, CYCLIND1, and CYCLINA were significantly inhibited after NR1D1 overexpression, which was also supported by the CCK-8 test, whereas differentiation marker genes MYOD, MYOG, and MYF5 were significantly inhibited. Fluorescence-specific staining showed that KI-67 protein abundance and the number of microfilaments both decreased, while the opposite trend was observed after NR1D1 interference. In conclusion, we confirmed that NR1D1 inhibited the proliferation and differentiation of yak skeletal muscle satellite cells, which provides a theoretical basis for further research on the effect of NR1D1 on improving meat quality traits and meat production performance of yaks.

Methyl Donor Micronutrients Orchestrate Lipid Metabolism: The Role of DNA Methylation Modification

DNA methylation, a key epigenetic modification, plays a crucial role in regulating lipid metabolism. Consistent correlations have been observed between aberrant DNA methylation patterns and lipid metabolic disorders. Emerging evidence indicates that methyl donor micronutrients could influence DNA methylation patterns, consequently exerting an influence on lipid metabolism. Specifically, the deficiency or excesses of methyl donor micronutrients (folate, choline, betaine, B vitamins and methionine) have been associated with altered DNA methylation patterns linked to lipid metabolism. These alteration in DNA methylation levels, occurring globally and within promoter regions, could affect gene expression related to lipid metabolism. However, the mechanisms through which methyl donor micronutrients regulate lipid metabolism via the DNA methylation modification and the role of methyl donor micronutrients supplementation on DNA methylation profiles remain unclear. In this review, we summarized the regulatory role of DNA methylation in lipid metabolism, and highlighted recent findings investigating the impact of methyl donor micronutrients on lipid metabolism, as well as DNA methylation-mediated adipogenesis and adipose deposition. Taken together, this review deepened our understanding of how the complex interplay between methyl donor micronutrients, DNA methylation, and lipid metabolism, and provides valuable information for accurately regulating lipid metabolism of livestock and poultry, thereby improving meat quality, and promoting the development of animal husbandry.

Effects of preslaughter handling approach and aging on carcass and meat quality attributes in goats

This study aimed to assess the impact of preslaughter handling method and aging on carcass and meat quality traits in goats. Twenty-seven male goats of Ardi breed were assigned into three treatment groups viz., the control (C), ear pulling (EP), and hind-leg pulling (HP). The carcasses were stored for post-mortem aging periods of 1, 7, and 14 days. On day 0 and the respective aging days, samples of the Longissimus thoracic et lumborum (LTL) muscles were collected and examined for various meat quality parameters. The preslaughter handling of goats significantly increase the total bacterial count, total Enterobacteriaceae count, and total Clostridium count. It also had a significant effect on the pH of LTL muscle during aging. A significantly lower values for pH were recorded in the treatment groups (EP and HP) as compared to the pH of the C group on day 1 of aging. Notably, both treatment groups were found to increase the shear force, hardness, and chewiness of the meat, ultimately compromising its quality. The proper treatment of meat animals, especially goats, is crucial for enhancing carcass and meat quality. Careful preslaughter handling practices by avoiding ear and hind-leg pulling can minimize negative impacts on the final product. Therefore, the significance of conducting this study lies in its potential to enhance animal welfare, improve meat quality, boost economic benefits for producers, and foster consumer confidence in meat products.

Enhancing growth performance and health of coloured-broiler chickens with signal grass meal (Brachiaria decumbens) supplementation under tropical conditions

This study examines the impact of signal grass (Brachiaria decumbens) as a phytobiotic supplement on the production performance and health of coloured-broiler chickens reared in tropical environments. A total of 216 day-old Sasso broiler chicks were randomly assigned to six treatment groups with six replications each. All six treatments received the same commercial diets with some adjustments: Treatment 1 (negative control) with only commercial feed, Treatment 2 (positive control) with 100 mg kg-1g kg-1 oxytetracycline, Treatment 3, 4, 5, and 6 with 1.25, 2.50, 3.75, and 5.00 g kg-1 of B. decumbens grass meal, respectively, without antibiotic. Throughout the eight-week study, body weight and feed intake were recorded weekly for each replicate to calculate body weight gain and feed conversion ratio. Additional evaluations included nutrient digestibility, gut histomorphology, cecal microflora population, carcass characteristics, and meat quality. Blood biomarkers and biochemistry were also analysed to evaluate the chickens' health status. Results indicated that broilers supplemented with B. decumbens grass meal, particularly T6 showed significantly (p<0.05) superior growth performance compared to the negative with reduced FCR of 6.8%. Apparent ileal digestibility was also significantly improved in T6, with 22.32% higher CP digestibility. Enhanced gut histomorphology and a healthier cecal microbial population supported improved nutrient absorption and overall gut health, as evidenced by significant increases in the villi-to-crypt ratio and a higher coliform count than the control. Enhanced carcass characteristics, such as higher full gizzard and gastrointestinal tract weights of T6 broilers, further supported improved digestibility. The supplementation also improved meat quality, with blood biomarkers indicating lower stress and inflammation levels comparable to T2. Additionally, the blood biochemistry of T6 broilers suggested hepatoprotective and hypocholesterolemic effects. Therefore, broilers in T6 demonstrated that B. decumbens has significant potential as an effective feed additive to replace antibiotics in the tropical poultry sector due to its phytocompounds profile, including high saponin content.

Sustainable improvement of broiler meat quality using glucomannan extract from porang tubers (Amorphophallus oncophyllus Prain) as prebiotic

Abstract Glucomannan is a prebiotic present in porang tubers can improve digestive health and nutritional efficiency of animal feed thus affecting the quality of meat produced. The study purposed to evaluate the impact of glucomannan extract from porang tubers (Amorphophallus oncophyllus Prain) as prebiotic on the physical and chemical quality of broiler meat. Conducted at the Flour House, Research and Technology Laboratory, Chemistry Laboratory of FMIPA, and Baru Village, Pancur Batu District, Deli Serdang Regency in February 2024. The average initial weight of broilers was 1484.17 ± 81.45 g. The research used a completely randomized design (CRD) with four treatments: 0%, 0.2%, 0.4%, and 0.6% glucomannan, each with five replicates. Parameters measured included pH, water holding capacity (WHC), cooking loss, moisture content, fat content, and protein content. The results showed that the 0.4% glucomannan treatment produced the best results, with significantly improved pH stability, increased WHC, reduced cooking loss, and increased crude protein content while decreasing fat content. These results suggest that 0.4% glucomannan supplementation optimally improves the nutritional and physical quality of broiler meat. In conclusion, the inclusion of 0.4% glucomannan in broiler diets can improve meat quality and provide a sustainable alternative to synthetic feed additives in poultry production.

Transcriptomics and non-targeted metabolomics provide mechanistic insights into the improvement of the growth performance and meat quality of lambs supplemented with fermented Lycium barbarum residues

This study investigated the effects of Lycium barbarum residues (LBR) and fermented L. barbarum residues (FLBR) on the growth performance and meat quality of lambs. Eighteen lambs were randomly assigned into three groups and fed either a basal diet (CON) or the same diet supplemented with 5.0% LBR or FLBR for a period of 90 days. The underlying mechanisms responsible for the beneficial effect of LBR and FLBR on the longissimus thoracis (LT) and intramuscular fat (IMF) tissues of lambs were examined using multiomics techniques. Our findings showed that FLBR supplementation significantly enhanced the average daily gain, feed efficiency, and nutrient digestibility (P < 0.05 or P < 0.01). Serum total protein (P = 0.007) and glucose (P = 0.002) levels were higher in the FLBR-fed lambs, while urea nitrogen level was lower (P = 0.001). Additionally, the levels of rumen acetate (P = 0.002) and propionate (P = 0.011) were significantly elevated, while NH3-N, isobutyrate and isovalerate decreased (P < 0.05 or P < 0.01) following FLBR supplementation. Post-mortem meat quality was also improved by FLBR, as evidenced by enhanced total antioxidant capacity, superoxide dismutase activity, pH, color a*, tenderness and water holding capacity (P < 0.05 or P < 0.01), alongside a reduction in the malonaldehyde content (P < 0.001). Transcriptomic analysis identified 962 differentially expressed genes (DEGs, FLBR vs CON) and 782 DEGs (FLBR vs LBR) in LT, and 1313 DEGs (FLBR vs CON) and 1221 DEGs (FLBR vs LBR) in IMF. The ribosome signaling pathway related genes in LT tissue were activated by the FLBR diet (P < 0.05), showing a higher anabolism of protein. The genes involved in fatty acid biosynthesis in IMF tissue were upregulated by the FLBR diet (P < 0.05), showing a higher anabolism of lipids. Metabolomics analysis identified the 1732 differential metabolites in LT tissue following FLBR supplementation, with significant alterations in metabolites such as carnosine, L-arginine and L-proline, which may serve as potential biomarkers for meat quality betterment. In conclusion, FLBR supplementation might have modified anabolism of proteins and fatty acid, as well as muscle metabolomic profiles, leading to improvements in both growth performance and meat quality in fattening lambs.

Effect of precursor amino acids for carnosine synthesis on breast fiber microstructures and myofiber differentiation-related gene expression in slow-growing chicken.

The effects of carnosine synthesis on the structural and microstructural determinants of meat quality have not been studied to date. Therefore, this study aimed to investigate the effect of supplementation with carnosine synthesis precursors on the characteristics and microstructure of breast muscle fibers in slow-growing Korat chickens (KR). Slow-growing KR were fed a non-supplemented commercial diet (control group) or a commercial diet supplemented with 1.0% β-alanine, 0.5% L-histidine, or a combination of both 1.0% β-alanine and 0.5% L-histidine. At 10 weeks, KR were slaughtered, and the breast muscle was collected. Samples were fixed and extracted to study the microstructure, fat level, and porosity of the meat using X-ray and scanning electron microscopy, and real-time polymerase chain reaction was performed to analyze the expression of genes related to myofiber differentiation. L-histidine supplementation significantly altered myofiber diameter and muscle fiber density and compactness by regulating muscle fiber-type differentiation via carnosine synthase (CARNS1) and myocyte enhancer factor 2C expression, as well as myogenic differentiation antigen and myogenic regulatory factor 5 expression. While excess L-histidine potentially stimulated CARNS1 to modify muscle fiber arrangement and tenderness in breast meat, dietary β-alanine supplementation alone or in combination with L-histidine supplementation induced a relatively less remarkable but not significant (p<0.05) effect on the breast meat characteristics studied. Interestingly, the combination of β-alanine and L-histidine supplementation had no effect on meat microstructure, meat porosity, and fat content in comparison with the control group. Thus, this combination had the best selectivity for improving meat quality. However, further studies are required to clarify the effects of carnosine levels on meat processing.

Transcriptome and targeted metabolome analysis of lipid profiles, nutrients compositions and volatile compounds in longissimus dorsi of different pig breeds.

Improving meat quality is important for commercial production and breeding. The molecular mechanism of intramuscular fat (IMF) deposition and meat characteristics remain further study. This study aimed to study the mechanism of IMF deposition and meat characteristics including redox potential, nutrients compositions and volatile compounds in longissimus dorsi (LD) by comparing with different pig breeds including Shanghai white (SW), Duroc x (Landrace Yorkshire) (DLY) and Laiwu (LW) pigs. Results showed that the contents of IMF, triglyceride (TG), total cholesterol (TC), and redox potential parameters were lower, while the content of MDA and activity of lactate dehydrogenase (LDH) were higher in LD of SW pigs compared with LW pigs (p<0.05). No differences were observed about these parameters between SW and DLY pigs. Also, the contents of medium-long chain fatty acids and γ-aminobutyric acid (GABA) were higher, while Asp was lower in LD of SW pigs compared with LW pigs (p<0.05). Volatile compounds results showed that 6 ketones, 4 alkenes, 11 alkanes, 2 aldehydes, 1 alcohol were increased and cholesterol was decreased in SW pigs compared with LW pigs. Transcriptome results showed that differential expressed genes involved in lipid synthesis, metabolism and transport in LD between SW and LW pigs, which were further verified by qPCR. Spearman correlation showed that HSL and Nedd4 were positively related to contents of TG and IMF, while negatively related to volatile compounds and fatty acids (p<0.05). Plin3 and Mgll were negatively related to contents of TG, IMF and cholesterol, while positively related to MDA, LDH, and volatile compounds (p<0.05). PPARA was negatively related to contents of TC and IMF, and activity of SOD, while positively related to volatile compounds (p<0.05). Our study provided new insights into potential mechanisms of IMF deposition, nutrients composition and volatile compounds of muscular tissues of different pig breeds.