Search Results (67)

Extensive beef systems in the tropics are the cheapest but require more land and longer rearing times with environmental impact. This study was carried out to evaluate three beef bull’s production systems in tropics: pasture-based system (PASTU), feedlot system immediately after weaning (FELOT) and a system with the combination of rearing in pasture and finishing in feedlot (PRIME) on animal performance and carcass characteristics of 30 bulls crossbred Angus x Nellore. The final weight, average daily gain and carcass weight (hot and cold) were higher (p < 0.050) for the FELOT system, intermediate for the PRIME system and lowest for the PASTU system. The carcass dressing (hot and cold), dripping losses, ratio (Longissimus dorsi) and degree of finishing were similar (p > 0.050). The carcass pH_24h was higher for the PRIME system (p < 0.010). Subcutaneous fat thickness (mm) was lower for the PASTU system (p < 0.050). Marbling was better for the PRIME system. The tissular composition was similar among systems related to muscle percentage but PASTU showed the highest bone percentage (p < 0.050) and lowest of adipose (p < 0.050). PRIME enable cost-effective, fast beef production with less environmental impact. Full article

Deposition of intramuscular fat (IM), also known as marbling, is the deciding factor of beef quality grade in the U.S. Defining molecular mechanisms underlying the differential deposition of adipose tissue in distinct anatomical areas in beef cattle is key to the development of strategies for marbling enhancement while limiting the accumulation of excessive subcutaneous adipose tissue (SAT). The objective of this exploratory study was to define the IM and SAT transcriptional heterogeneity at the whole tissue and single-nuclei levels in beef steers. Longissimus dorsi muscle samples (9–11th rib) were collected from two finished beef steers at harvest to dissect matched IM and adjacent SAT (backfat). Total RNA from IM and SAT was isolated and sequenced in an Illumina NovaSeq 6000. Nuclei from the same samples were isolated by dounce homogenization, libraries generated with 10× Genomics, and sequenced in an Illumina NovaSeq 6000, followed by analysis via Cell Ranger pipeline and Seurat in RStudio (v4.3.2) By the expression of signature marker genes, single-nuclei RNA sequencing (snRNAseq) analysis identified mature adipocytes (AD; ADIPOQ, LEP), adipose stromal and progenitor cells (ASPC; PDGFRA), endothelial cells (EC; VWF, PECAM1), smooth muscle cells (SMC; NOTCH3, MYL9) and immune cells (IMC; CD163, MRC1). We detected six cell clusters in SAT and nine in IM. Across IM and SAT, AD was the most abundant cell type, followed by ASPC, SMC, and IMC. In SAT, AD made up 50% of the cellular population, followed by ASPC (31%), EC (14%), IMC (1%), and SMC (4%). In IM depot, AD made up 23% of the cellular population, followed by ASPC at 19% of the population, EC at 28%, IMC at 7% and SMC at 12%. The abundance of ASPC and AD was lower in IM vs. SAT, while IMC was increased, suggesting a potential involvement of immune cells on IM deposition. Accordingly, both bulk RNAseq and snRNAseq analyses identified activated pathways of inflammation and metabolic function in IM. These results demonstrate distinct transcriptional cellular heterogeneity between SAT and IM depots in beef steers, which may underly the mechanisms by which fat deposits in each depot. The identification of depot-specific cell populations in IM and SAT via snRNAseq analysis has the potential to reveal target genes for the modulation of fat deposition in beef cattle. Full article

Beef fat injection technology, used to enhance the perceived quality of lower-grade meat, often results in artificially marbled beef that mimics the visual traits of Wagyu, characterized by dense fat distribution. This practice, driven by the high cost of Wagyu and the affordability of fat-injected beef, has led to the proliferation of mislabeled “Wagyu-grade” products sold at premium prices, posing potential food safety risks such as allergen exposure or consumption of unverified additives, which can adversely affect consumer health. Addressing this, this study introduces a smart sensing system integrated with handheld mobile devices, enabling consumers to capture beef images during purchase for real-time health-focused assessment. The system analyzes surface texture and color, transmitting data to a server for classification to determine if the beef is artificially marbled, thus supporting informed dietary choices and reducing health risks. Images are processed by applying a region of interest (ROI) mask to remove background noise, followed by partitioning into grid blocks. Local binary pattern (LBP) texture features and RGB color features are extracted from these blocks to characterize surface properties of three beef types (Wagyu, regular, and fat-injected). A support vector machine (SVM) model classifies the blocks, with the final image classification determined via majority voting. Experimental results reveal that the system achieves a recall rate of 95.00% for fat-injected beef, a misjudgment rate of 1.67% for non-fat-injected beef, a correct classification rate (CR) of 93.89%, and an F1-score of 95.80%, demonstrating its potential as a human-centered healthcare tool for ensuring food safety and transparency. Full article

Deposition of intramuscular adipose tissue (IMAT) is the primary determinant for beef quality grade in the U.S. Accumulation of subcutaneous (SCAT) and visceral (VIAT) adipose tissue precedes that of IMAT and often leads to excessive adiposity in beef cattle. Approaches to increase marbling while limiting subcutaneous and visceral adiposity are limited. Our objective is to define the depot-specific transcriptome profile and adipocyte function in IMAT, SCAT, and VIAT in beef steers. Transcriptomics revealed the upregulation of adipogenic and lipogenic genes in SCAT and VIAT vs. IMAT. Functional transcriptome analysis demonstrated the activation of pathways for lipid metabolic processes and biosynthesis in SCAT, accompanied by increased preadipocyte proliferation, adipocyte size, and insulin responses of SCAT in vitro. While IMAT had a greater abundance of preadipocytes, they proliferated at a lower rate and differentiated into adipocytes that were smaller and less responsive to insulin compared to SCAT. The upregulation of extracellular matrix genes in IMAT suggests that fat accumulation may be limited by the muscle microenvironment. The activation of inflammatory and immune response pathways, combined with a higher abundance of immune cells, highlighted VIAT as an immune-responsive depot. Our findings reveal transcriptional and cellular profiles underlying fat deposition in SCAT, VIAT, and IMAT in beef cattle. Full article

This study analyzes Brazilian consumer behavior regarding quality and visual cues in fresh red meat and cooked beef. Using eye tracking to collect visual attention metrics and psychological scales to assess food behavior, the research examines how visual attention to beef attributes impacts product choice. A discrete choice method combined nine hypothetical products with varied attributes. Results showed that consumers display different visual behaviors toward cues, influencing their probability of choosing a product. For fresh beef, color was the most significant factor, especially bright red and brown hues. Color influenced both the time to first fixation and total fixation time, while breed also affected total fixation time. Dark-red color and unspecified breed information increased the purchase probability, while Nellore breed and brown color decreased it. Total fixation numbers were significantly impacted by color, breed, marbling, and price. In cooked beef, tenderness, price, and flavor were key visual cues. Tenderness and flavor influenced the time to first fixation, whereas price and flavor impacted the number of fixations. This research contributes to understanding visual cues and attention in food choices, suggesting strategies for enhancing beef labeling and communication to better inform Brazilian consumers. Full article

Beef carcass grading plays a pivotal role in determining market value and consumer preferences. While traditional visual inspection by experts remains the industry standard, it suffers from subjectivity and inconsistencies, particularly in high-throughput slaughterhouse environments. To address these limitations, we propose a one-stage automated grading model based on EfficientViT, a lightweight vision transformer architecture. Unlike conventional two-stage methods that require prior segmentation of the loin region, our model directly predicts beef quality grades from raw RGB images, significantly simplifying the pipeline and reducing computational overhead. We evaluate the proposed model against representative convolutional neural networks (VGG-16, ResNeXt-50, DenseNet-121) as well as two-stage combinations of segmentation and classification models. Experiments were conducted on a publicly available beef carcass dataset consisting of over 77,000 labeled images. EfficientViT achieves the highest accuracy (98.46%) and F1-score (0.9867) among all evaluated models while maintaining low inference latency (3.92 ms) and compact parameter size (36.4 MB). In particular, it outperforms CNNs in predicting the top grade (1++), where global visual patterns such as marbling distribution are crucial. Furthermore, we employ Grad-CAM and attention map visualizations to analyze the model’s focus regions and demonstrate that EfficientViT captures holistic contextual features better than CNNs. The model also exhibits robustness across varying loin area proportions. Our findings suggest that EfficientViT is not only accurate but also efficient and interpretable, making it a strong candidate for real-time industrial applications in beef quality grading. Full article

Maternal overnutrition and targeted supplements during pregnancy strongly affect fetal development in beef cattle, influencing gene expression, tissue development, and productivity after birth. As modern feeding practices often result in cows receiving energy and protein above requirements, understanding the balance between adequate nutrition and overconditioning is critical for sustainable beef production. This review synthesizes findings from recent studies on maternal overnutrition and supplementation, focusing on macronutrients (energy, protein, methionine) and key micronutrients (e.g., selenium, zinc). It evaluates the timing and impact of supplementation during different gestational stages, with emphasis on fetal muscle and adipose tissue development, immune function, and metabolic programming. The role of epigenetic mechanisms, such as DNA methylation and non-coding RNAs, is also discussed in relation to maternal dietary inputs. Mid-gestation supplementation promotes muscle growth by activating muscle-specific genes, whereas late-gestation diets enhance marbling and carcass traits. However, maternal overnutrition may impair mitochondrial efficiency, encourage fat deposition over muscle, and promote collagen synthesis, reducing meat tenderness. Recent evidence highlights sex-specific fetal programming differences, the significant impact of maternal diets on offspring gut microbiomes, and breed-specific nutritional responses, and multi-OMICs integration reveals metabolic reprogramming mechanisms. Targeted trace mineral and methionine supplementation enhance antioxidant capacity, immune function, and reproductive performance. Precision feeding strategies aligned with gestational requirements improve feed efficiency and minimize overfeeding risks. Early interventions, including protein and vitamin supplementation, optimize placental function and fetal development, supporting stronger postnatal growth, immunity, and fertility. Balancing nutritional adequacy without excessive feeding supports animal welfare, profitability, and sustainability in beef cattle systems. Full article

Marbling is a crucial indicator that significantly impacts beef quality grading. Currently, Chinese beef processing enterprises rely on professional graders who visually assess marbling using national standard atlases. However, this manual evaluation method is highly subjective and time consuming. This study proposes a beef marbling grading algorithm based on an enhanced YOLOv8x model to address these challenges. The model integrates a convolutional neural network (CNN) augmented with an improved attention mechanism and loss function, along with a Region-of-Interest (ROI) preprocessing algorithm to automate the marbling grading process. A dataset comprising 1300 beef sample images was collected and split into training and test sets at an 8:2 ratio. Comparative experiments were conducted with other deep learning models as well as ablation tests to validate the proposed model’s effectiveness. The experimental results demonstrate that the improved YOLOv8x achieves a validation accuracy of 99.93%, a practical grading accuracy of 97.82%, and a detection time of less than 0.5 s per image. The proposed algorithm enhances grading efficiency and contributes to intelligent agricultural practices and livestock product quality assessment. Full article

This study evaluates the effects of a proprietary tannin blend (BX), supplemented with or without sodium monensin (MON), on beef cattle performance, carcass traits, and health. Steers (n = 2986; initial shrunk body weight (SBW) 254 ± 9.2 kg) were allocated into 48 pens (61–62 steers/pen; 12 pens/treatment) fed for 230 d. Treatments included: (1) no feed additives (CTL); (2) BX (7.95 g/animal daily); (3) MON + Tylosin phosphate (TYL; 437.52 mg MON/animal daily + 80 mg TYL/animal daily); or (4) MON + BX (437.52 mg MON/animal daily + 7.95 g BX/animal daily). Data were analyzed in R 4.2.1 using a randomized block design with pen as the experimental unit. Dry matter intake was lower (p < 0.001) in MON + TYL and MON + BX than in CTL. Steers fed MON + BX had greater carcass-adjusted final SBW (p = 0.002), average daily gain (p = 0.002), fat thickness (p = 0.035), and marbling score (p = 0.046) than BX. Feed conversion improved in MON + TYL and MON + BX (p < 0.001). CLT and BX had higher (p < 0.001) liver abscess prevalence compared to MON + BX and MON + TYL. The addition of BX did not improve the parameters measured. Steers fed MON + BX showed reduced liver abscesses and similar feed efficiency compared to MON + TYL. Full article

Intramuscular fat (IMF) content in beef cattle is a critical determinant of beef meat quality, as it positively influences juiciness, tenderness, and palatability. In China, the crossbreeding of Wagyu and Angus is a prevalent method for achieving a better marbling level. However, the molecular mechanisms governing IMF regulation in these crossbreeds remain poorly understood. To elucidate the mechanism of IMF deposition in these crossbred cattle, we conducted a comparative transcriptomic analysis of longissimus dorsi muscles and livers from cattle with divergent IMF content. RNA-seq revealed 940 and 429 differentially expressed genes (DEGs) in the liver and muscle, respectively, with 60 genes co-differentially expressed (co-DEGs) in both tissues. Functional enrichment highlighted lipid metabolism pathways including fatty acid β-oxidation, PPAR signaling, and glycerolipid metabolism. A total of eleven genes including ACAA2, ACADL, ACOX2, CPT1B, CPT2, LPL, SLC27A1, ACAT1, GK, ACOX3, and ACSM5, were screened as key candidate genes for IMF deposition. A “liver–muscle” regulatory network of IMF deposition was built to illustrate the tissues’ interaction. The reliability of the transcriptomic data was verified by quantitative reverse real-time PCR (qRT-PCR). Our findings provide novel molecular markers for increasing the IMF content and accelerating the genetic improvement of beef quality traits in crossbred cattle. Full article

Genetic polymorphisms have a great impact on enhancing quantitative traits in cattle. In this study, Fatty acid synthase (FASN) g. 16024 (A>G), Stearoyl-CoA desaturase (SCD) g. 10329 (C>T), and pleomorphic adenoma gene (PLAG1) g. 25003338 (C>G) genotypic and allelic polymorphisms were evaluated, along with their associations with fatty acid composition, adipogenic gene expression, and carcass characteristics (carcass weight, yield grade, backfat thickness, and marbling score) in Hanwoo steers. A total of 128 Hanwoo steers were selected for this study and the Polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method was used to identify polymorphism of these genes. The AG genotype and G allele in FASN g. 16024 (A>G), CT genotype and T allele in SCD g. 10329 (C>T), and GG genotype and G allele in PLAG1 g. 25003338 (C>G) showed higher frequency and positively correlated with carcass traits, yield, and quality grades. Fatty acid composition results indicate that C18:3n-6, C20:1, and C20:2n-6 were significantly higher in the AA genotype of FASN gene, C14:1 and C18:3n-6 in the CC genotype, and C16:1 in the TT genotype of SCD gene. C12:0, C14:0, C16:1, C18:0, and C20:0 were higher in the CC genotype of PLAG1 gene. Furthermore, RT-qPCR analysis of adipogenesis-related genes (AMP-activated protein kinase-α (AMPKα), Carnitine palmitoyl transferase-1β (CPT1), G-coupled protein receptor-43 (GPR43), and SCD) across different SNP genotypes suggests a systemic interaction between genetic factors and adipogenesis in beef cattle. This study emphasizes the significance of FASN g. 16024 (A>G), SCD g. 10329 (C>T), and PLAG1 g. 25003338 (C>G) SNPs for genetic selection to enhance beef quality and elucidate lipid metabolic pathways in Hanwoo cattle. Full article

The use of non-invasive technologies is among the most accurate methods for assessing meat quality parameters. Beef tenderness and palatability are strongly influenced by the amount of intramuscular fat, commonly referred to as marbling. Marbling is widely used in breeding programs to select animals with superior meat quality. In this study, we analyzed 236 Angus bulls and 22 Angus heifers from various farms in Lithuania, all aged 450 ± 112 days. Ultrasound examinations were performed using a linear transducer with a silicone standoff to evaluate the loin eye area. Key meat quality indicators, such as fat thickness, loin area and thickness, and intramuscular fat, were found to increase with the weight of bulls, ranging from 365 ± 12.70 kg to 825.57 ± 11.75 kg (p < 0.001), and heifers, ranging from 273 ± 20.71 kg to 767 ± 41.01 kg (p < 0.001). The highest intramuscular fat values were observed at 7.50 ± 0.75% (p < 0.05) to 6.9 ± 1.36% (p < 0.1) in bulls weighing 431.33–825.57 kg and 7.98 ± 0.28% (p < 0.001) in heifers weighing 603 kg. These findings demonstrate the feasibility of selecting Angus cattle for improved meat quality traits across different weight categories. Full article

The study objective was to compare the palatability of beef strip loin steaks from young and mature grain-finished cattle across a range of marbling scores. Grain-finished beef carcasses were selected from two maturity groups: old maturity (O; >30 months of age) and young maturity (Y; <30 months of age). Within maturity groups, carcasses were selected to represent five marbling degrees—slightly abundant or greater (SLAB), moderate (MD), modest (MT), small (SM), and slight (SL)—resulting in ten treatment groups. Longissimus dorsi samples were removed on day 2 postmortem and cut into 2.5 cm thick steaks for slice shear force measurement, consumer palatability analysis, and proximate analysis. Tenderness, juiciness, flavor liking and intensity, overall liking, acceptability, and willingness to pay were all affected (p < 0.01) by treatment group. Palatability ratings generally decreased as marbling score decreased, but adjacent marbling scores often produced similar eating quality. Maturity had the most apparent impact on tenderness, as Y vs. O maturity samples scored greater (p < 0.05) for tenderness within four of the marbling scores (SLAB, MD, MT, and SL). Maturity had limited to no impact on juiciness, flavor intensity, and flavor liking. SLAB-Y and MD-Y were more liked overall compared to their O counterparts, but no other maturity differences were noted for overall liking within marbling scores. Grain-finished mature cull cows generated a similar or slightly reduced eating experience to young beef, but greater marbling is required to offset tenderness differences in mature beef. Full article

The genetic improvement of beef cattle breeds is crucial for the advancement of the beef cattle industry. Whole-genome resequencing technology has been widely applied in genetic breeding as well as research on selection signatures in beef cattle. In this study, 20× whole-genome resequencing was performed on 282 Angus cattle from the Ningxia region, and a high-quality dataset encompassing extensive genomic variations across the entire genome was constructed. The iHS test identified 495 selection signal regions, which included pregnancy-associated glycoprotein (PAG) family genes and immune-related genes such as UL16-binding protein 21 (ULBP21), CD1b molecule (CD1B), and tumor necrosis factor ligand superfamily member 11 (TNFSF11). A quantitative trait locus (QTL) enrichment analysis revealed that several economic traits, including longissimus muscle area, marbling score, carcass weight, average daily gain, and milk yield, were significantly enriched in cattle with these selection signatures. Although the enrichment of QTLs for health traits was low, immune-related genes may indirectly contribute to improvements in production performance. These findings show the genetic basis of economic and adaptive traits in Ningxia Angus cattle, providing a theoretical foundation and guidance for further genetic improvement and breeding strategies. Full article

Wagyu beef is gaining worldwide popularity, primarily due to the fineness of its marbling. Currently, the evaluation of this marbling is performed visually by graders. This method has several issues: varying evaluation standards among graders, reduced accuracy due to long working hours and external factors causing fatigue, and fluctuations in grading standards due to the grader’s mood at the time. This paper proposes the use of fractal analysis for the grading evaluation of beef marbling to achieve automatic grading without the inconsistencies caused by human factors. In the experiments, cross-sectional images of the parts used for visual judgment were taken, and fractal analysis was performed on these images to evaluate them using fractal dimensions. The results confirmed a correlation between the marbling evaluation and the fractal dimensions, demonstrating that quantitative evaluation can be achieved, moving away from qualitative visual assessments. Full article