Meat tenderness is a critical quality trait that varies even among carcasses of similar USDA quality grades. In this comparative study of beef cattle and sheep, we investigated how gene expression profiles in muscle and adipose tissues are associated with carcass quality grades and Fat Classes. Fifteen steers and fifteen wethers were raised to produce carcasses spanning Standard, Select, and Choice USDA quality grades (beef) or varying Fat Classes (sheep). In beef, higher quality grade was associated with significantly improved tenderness (lower shear force), while sheep tenderness did not differ consistently across Fat Classes. Exploratory RNA sequencing identified hundreds to thousands of differentially expressed genes (DEGs) between high- and low-quality or fatness groups, particularly in sheep muscle. DEGs were enriched in pathways related to muscle growth, lipid metabolism, and immune signaling. While these transcriptomic differences suggest biological processes associated with carcass traits, the findings are correlational, should be interpreted as hypothesis-generating, and require further validation in larger independent populations. These exploratory findings suggest species-specific differences in the relationship between fatness and tenderness and identify candidate molecular pathways for future investigation.

In the Results and Discussion section of this article, 2 values were inverted. The 2 corrected numbers are marked in boldface below. There were 261 cows from 32 farms classified into 1 of the 3 acidosis risk groups, 26.1% of the cows classified as high risk, 26.8% as medium risk, and 47.1% as low risk for acidosis (Table 3). The authors regret the error. Characterizing ruminal acidosis risk: A multiherd, multicountry studyJournal of Dairy ScienceVol. 106Issue 5PreviewA multicenter observational study was conducted on early lactation Holstein cows (n = 261) from 32 herds from 3 regions (Australia, AU; California, CA; and Canada, CAN) to characterize their risk of acidosis into 3 groups (high, medium, or low) using a discriminant analysis model previously developed. Diets ranged from pasture supplemented with concentrates to total mixed ration (nonfiber carbohydrates = 17 to 47 and neutral detergent fiber = 27 to 58% of dry matter). Rumen fluid samples were collected <3 h after feeding and analyzed for pH, and ammonia, d- and l-lactate, and volatile fatty acid (VFA) concentrations. Full-Text PDF Open Access

Background and Objectives: With continued advances in treatment options, patients with endoprosthetic reconstruction are living longer and consequently relying upon their devices for a longer duration. Major causes of endoprosthesis failure include aseptic loosening and mechanical failure. In the setting of tumor resection, loss of bone stock and use of radiation therapy increase the risk for these complications. As such, considerations of remaining native bone and stem length and diameter may be increasingly important. We asked the following questions: (1) What was the overall rate of endoprosthesis failure at a minimum of 5-year follow-up? (2) Does resection length increase implant failure rates? (3) Does implant size and its ratio to cortical width of bone alter implant failure rates?Methods: We retrospectively analyzed patient outcomes at a single institution between the years of 1999-2022 who underwent cemented endoprosthetic reconstruction at the hip or knee and identified 150 patients. Of these 150, 55 had a follow-up of greater than 5 years and were used for analysis. Radiographs of these patients at time of surgery were assessed and measured for resection length, bone diameter, stem diameter, and remaining bone length. Resection percentage, and stem to bone diameter ratios were then calculated and their relationship to endoprosthesis failure were analyzed.Results: Patients in this cohort had a mean age of 55.8, and mean follow-up of 59.96 months. There were 78 distal femoral replacements (52%), 16 proximal femoral replacements (10.7%), and 56 proximal tibial replacements (37.3%). There were five patients who experienced aseptic loosening and six patients who experienced mechanical failure. Patients with implant failure had a smaller mean stem to bone diameter (36% vs. 44%; p = 0.002). A stem to bone diameter of 40% appeared to be a breaking point between success and failure in this series, with 90% of patients with implant failure having a stem: bone ratio less than 40%. Stem to bone ratio less than 40% increased risk for failure versus stems that were at least 40% the diameter of bone (6/19 [31.6%] vs. 0/36 [0%]; odds ratio 0.68; p < 0.001). Resection length did not appear to have an impact on the rates of aseptic loosening and mechanical failure in this series.Conclusions: Data from this series suggests a benefit to using stems with a larger diameter when implanting cemented endoprostheses at the hip or knee. Stems which were less than 40% the diameter of bone were substantially more likely to undergo implant failure.

A multicenter observational study was conducted on early lactation Holstein cows (n = 261) from 32 herds from 3 regions (Australia, AU; California, CA; and Canada, CAN) to characterize their risk of acidosis into 3 groups (high, medium, or low) using a discriminant analysis model previously developed. Diets ranged from pasture supplemented with concentrates to total mixed ration (nonfiber carbohydrates = 17 to 47 and neutral detergent fiber = 27 to 58% of dry matter). Rumen fluid samples were collected <3 h after feeding and analyzed for pH, and ammonia, d- and l-lactate, and volatile fatty acid (VFA) concentrations. Eigenvectors were produced using cluster and discriminant analysis from a combination of rumen pH, and ammonia, d-lactate, and individual VFA concentrations and were used to calculate the probability of the risk of ruminal acidosis based on proximity to the centroid of 3 clusters. Bacterial 16S ribosomal DNA sequence data were analyzed to characterize bacteria. Individual cow milk volume, fat, protein, and somatic cell count values were obtained from the closest herd test to the rumen sampling date (median = 1 d before rumen sampling). Mixed model analyses were performed on the markers of rumen fermentation, production characteristics, and the probability of acidosis. A total of 26.1% of the cows were classified as high risk for acidosis, 26.8% as medium risk, and 47.1% as low risk. Acidosis risk differed among regions with AU (37.2%) and CA (39.2%) having similar prevalence of high-risk cows and CAN only 5.2%. The high-risk group had rumen phyla, fermentation, and production characteristics consistent with a model of acidosis that reflected a rapid rate of carbohydrate fermentation. Namely, acetate to propionate ratio (1.98 ± 0.11), concentrations of valerate (2.93 ± 0.14 mM), milk fat to protein ratio (1.11 ± 0.047), and a positive association with abundance of phylum Firmicutes. The medium-risk group contains cows that may be inappetant or that had not eaten recently or were in recovery from acidosis. The low-risk group may represent cattle that are well fed with a stable rumen and a slower rumen fermentation of carbohydrates. The high risk for acidosis group had lower diversity of bacteria than the other groups, whereas CAN had a greater diversity than AU and CA. Rumen fermentation profile, abundance of ruminal bacterial phyla, and production characteristics of early lactation dairy cattle from 3 regions were successfully categorized in 3 different acidosis risk states, with characteristics differing between acidosis risk groups. The prevalence of acidosis risk also differed between regions.

Abstract Bovine respiratory disease (BRD) contributes to high rates of mortality and morbidity among feedlot animals. Thus, there is a need to discover robust predictive biological indicators of infection status and disease severity in feedlot cattle. This study aimed to explore the use of 1H nuclear magnetic resonance (NMR) based metabolite profiling to characterize serum molecular markers associated with a viral-bacterial respiratory disease challenge in beef cattle. Crossbred beef steers [n = 24; initial body weight (BW) = 293 kg) were inoculated intranasally with bovine herpes virus-1 (2×108 PFU) and intratracheally with Mannheimia haemolytica (MH, 2.15×1010 CFU) on d -3 and 0, respectively (n = 16; MH-challenge), or similarly inoculated with phosphate-buffered saline (n = 8; Control-challenge). Blood was collected via jugular venipuncture on d -3, -1, 0, 2, 3, 5, 7, 10, and 14 relative to MH challenge for complete blood count and haptoglobin analysis, with additional serum samples stored at -80°C for subsequent metabolomic analysis. Continuously recorded variables included rumen temperature, activity, rumination, dry matter intake, and feeding behavior. Wottlin et al. (2020) reported that rumen temperature was increased (P < 0.04) in MH-challenged steers until d 6 post-MH inoculation (40.8 vs 39.3°C in MH-challenged and Control-challenged steers several hours post-MH inoculation). Dry matter intake was reduced (P < 0.01) by 42% in MH-challenged compared with Control-challenged steers during the 14-d post-MH inoculation period. Further, haptoglobin concentrations were increased (P < 0.05) in MH-challenged steers from d 2 to 7 of the post-MH inoculation period. Serum samples underwent small molecule metabolite extraction and untargeted 1H NMR metabolomics. The 1H NMR spectra of serum metabolites were evaluated for this study, resulting in the unambiguous identification and quantification of 64 polar metabolites. Univariate analysis was conducted to examine the effect of the MH challenge on relative metabolite concentrations between d 2 and 5 relative to MH challenge, indicating differences between metabolites of MH-challenge and Control-challenged steers. However, multivariate analysis using unsupervised 2-dimensional principal component analysis (2D-PCA) could not differentiate MH-challenged from Control-challenged steers based on distinct serum metabolite profiles. Results indicate the potential of specific metabolites to indicate BRD infected cattle; however, a larger cohort of cattle and expanded metabolite profile coverage may be required to more fully differentiate between BRD vs healthy cohorts. Opportunities exist to further investigate the role of metabolomics to discover robust early biological indicators that are predictive of the onset of BRD in feedlot cattle.

A multicenter observational study to evaluate genome-wide association was conducted in early-lactation Holstein cows (n = 293) from 36 herds in Canada, the USA, and Australia. Phenotypic observations included rumen metabolome, acidosis risk, ruminal bacterial taxa, and milk composition and yield measures. Diets ranged from pasture supplemented with concentrates to total mixed rations (nonfiber carbohydrates = 17 to 47, and neutral detergent fiber = 27 to 58% of dry matter). Rumen samples were collected <3 h after feeding and analyzed for pH, ammonia, d- and l-lactate, volatile fatty acid (VFA) concentrations, and abundance of bacterial phyla and families. Eigenvectors were produced using cluster and discriminant analyses from a combination of pH and ammonia, d-lactate, and VFA concentrations, and were used to estimate the probability of the risk of ruminal acidosis based on proximity to the centroid of 3 clusters, termed high (24.0% of cows), medium (24.2%), and low risk (51.8%) for acidosis. DNA of sufficient quality was successfully extracted from whole blood (218 cows) or hair (65 cows) collected simultaneously with the rumen samples and sequenced using the Geneseek Genomic Profiler Bovine 150K Illumina SNPchip. Genome-wide association used an additive model and linear regression with principal component analysis (PCA) population stratification and a Bonferroni correction for multiple comparisons. Population structure was visualized using PCA plots. Single genomic markers were associated with milk protein percent and the center logged ratio abundance of the phyla Chloroflexi, SR1, and Spirochaetes, and tended to be associated with milk fat yield, rumen acetate, butyrate, and isovalerate concentrations and with the probability of being in the low-risk acidosis group. More than one genomic marker was associated or tended to be associated with rumen isobutyrate and caproate concentrations, and the center log ratio of the phyla Bacteroidetes and Firmicutes and center log ratio of the families Prevotellaceae, BS11, S24-7, Acidaminococcaceae, Carnobacteriaceae, Lactobacillaceae, Leuconostocaceae, and Streptococcaceae. The provisional NTN4 gene, involved in several functions, had pleiotropy with 10 bacterial families, the phyla Bacteroidetes and Firmicutes, and butyrate. The ATP2CA1 gene, involved in the ATPase secretory pathway for Ca2+ transport, overlapped for the families Prevotellaceae, S24-7, and Streptococcaceae, the phylum Bacteroidetes, and isobutyrate. No genomic markers were associated with milk yield, fat percentage, protein yield, total solids, energy-corrected milk, somatic cell count, rumen pH, ammonia, propionate, valerate, total VFA, and d-, l-, or total lactate concentrations, or probability of being in the high- or medium-risk acidosis groups. Genome-wide associations with the rumen metabolome, microbial taxa, and milk composition were present across a wide geographical and management range of herds, suggesting the existence of markers for the rumen environment but not for acidosis susceptibility. The variation in pathogenesis of ruminal acidosis in the small population of cattle in the high risk for acidosis group and the dynamic nature of the rumen as cows cycle through a bout of acidosis may have precluded the identification of markers for acidosis susceptibility. Despite a limited sample size, this study provides evidence of interactions between the mammalian genome, the rumen metabolome, ruminal bacteria, and milk protein percentage.

Targets for finished livestock are often determined by expected fat, either subcutaneous or intramuscular. These targets are used frequently to improve eating quality. Lower intramuscular fat, lack of product uniformity, and insufficient tenderness can negatively impact beef acceptability. This study aimed to investigate the differences in gene expression that alter metabolism and intercellular signaling in the muscle and adipose tissue in beef carcasses at different fat endpoints. In this study, longissimus thoracis muscle samples and adipose tissue were collected at harvest, and RNA was extracted and then sequenced using RNAseq. Differential expression was determined using edgeR, and p-values were adjusted using the Benjamini-Hochberg method. A corrected p-value of 0.005 and log2 (fold change) of >1 were the threshold to identify differential expression. Comparison between intermuscular and subcutaneous fat showed no differences in the genes activated in the two adipose tissue depots, suggesting that subcutaneous fat was an adequate sample. Carcass data allowed the classification of carcasses by USDA quality grades (marbling targets). In comparing muscle from Standard and Choice carcasses, 15 genes were downregulated, and 20 were upregulated. There were 49 downregulated and 113 upregulated genes comparing adipose tissue from Standard and Choice carcasses. These genes are related to the metabolism of fat and energy. This indicates that muscle transcript expression varies less than adipose. In addition, subcutaneous fat can be used to evaluate transcript changes in fat. However, it is unclear whether these fat tissues can be used as surrogates for marbling.

Growth is frequently described as weight gain over time. Researchers have used this information in equations to predict carcass composition and estimate fat deposition. Diet, species, breed, and gender all influence fat deposition. Alterations in diets result in changes in fat deposition as well as the fatty acid profile of meat. Additionally, the amount and composition of the fat can affect lipid stability and flavor development upon cooking. Fat functions not only as a storage of energy and contributor of flavor compounds, but also participates in signaling that affects many aspects of the physiological functions of the animal. Transcription factors that are upregulated in response to excess energy to be stored are an important avenue of research to improve the understanding of fat deposition and thus, the efficiency of production. Additionally, further study of the inflammation associated with increased fat depots may lead to a better understanding of finishing animals, production efficiency, and overall health.

Backfat and carcass fatness is an important quality attribute in meat animals. A substantial economic gain in the livestock industry may result from the discovery of metabolites, which can improve methods for predicting desirable livestock traits before harvest. Complex phenotypes can be identified for genetic selection or precision management using metabolic and genetic biomarkers. An analysis of ovine samples collected before harvest from wethers with different degrees of back fat was conducted using serum samples obtained from 15 sheep (5 from each back fat class), 60 d, 30 d, and just before harvest. This study quantified 55 serum metabolites that play important roles in ovine metabolism by 1H nuclear magnetic resonance (NMR) spectroscopy. An RNAseq dataset was generated from each sheep's muscle and adipose tissue at harvest. A statistical analysis of the data was performed using MetaboAnalyst Version 5.0 software in R. The results of multiple analyses showed that three metabolites, betaine, choline, and dimethylamine, are associated with sheep's fat class at a significance of (P < 0.01). Integration with gene expression datasets is still underway due to the limitations of annotating sheep genes. In addition, these metabolites are novel and have never been shown to modulate fat class in sheep. To elucidate methods of predicting which livestock produce ideal carcasses, further research is needed to investigate how betaine and choline impact fatness in sheep.

Fat deposition is important to carcass value and some palatability characteristics. Carcasses with higher USDA quality grades produce more value for producers and processors in the US system and are more likely to have greater eating satisfaction. Using genomics to identify genes impacting marbling deposition provides insight into muscle biochemistry that may lead to ways to better predict fat deposition, especially marbling and thus quality grade. Hereford steers (16) were managed the same from birth through harvest after 270 days on feed. Samples were obtained for tenderness and transcriptome profiling. As expected, steaks from Choice carcasses had a lower shear force value than steaks from Select carcasses; however, steaks from Standard carcasses were not different from steaks from Choice carcasses. A significant number of differentially expressed (DE) genes was observed in the longissimus lumborum between Choice and Standard carcass RNA pools (1257 genes, p < 0.05), but not many DE genes were observed between Choice and Select RNA pools. Exploratory analysis of global muscle tissue transcriptome from Standard and Choice carcasses provided insight into muscle biochemistry, specifically the upregulation of extracellular matrix development and focal adhesion pathways and the downregulation of RNA processing and metabolism in Choice versus Standard. Additional research is needed to explore the function and timing of gene expression changes.

Patients with cancer to bone or soft tissues undergoing orthopedic procedures may be unable to receive pharmacologic prophylaxis for venous thromboembolism (VTE). Inferior vena cava (IVC) filters may be an effective method to prevent fatal pulmonary embolism (PE) in these patients.

Indicator traits associated with disease resiliency would be useful to improve the health and welfare of feedlot cattle. A post hoc analysis of data collected previously (Kayser et al., 2019a) was conducted to investigate differences in immunologic, physiologic, and behavioral responses of steers (N = 36, initial BW = 386 ± 24 kg) that had differential haptoglobin (HPT) responses to an experimentally induced challenge with Mannheimia haemolytica (MH). Rumen temperature, DMI, and feeding behavior data were collected continuously, and serial blood samples were collected following the MH challenge. Retrospectively, it was determined that 9 of the 18 MH-challenged steers mounted a minimal HPT response, despite having similar leukocyte and temperature responses to other MH-challenged steers with a greater HPT response. Our objective was to examine differences in behavioral and physiological responses between MH-challenged HPT responsive (RES; n = 9), MH-challenged HPT nonresponsive (NON; n = 9), and phosphate-buffered saline-inoculated controls (CON; n = 18). Additionally, 1H NMR analysis was conducted to determine whether the HPT-responsive phenotype affected serum metabolite profiles. The RES steers had lesser (P < 0.05) cortisol concentrations than NON and CON steers. The magnitude of the increases in neutrophil concentrations and rumen temperature, and the reduction in DMI following the MH challenge were greatest (P < 0.05) in RES steers. Univariate analysis of serum metabolites indicated differences between RES, NON, and CON steers following the MH challenge; however, multivariate analysis revealed no difference between HPT-responsive phenotypes. Prior to the MH challenge, RES steers had longer (P < 0.05) head down and bunk visit durations, slower eating rates (P < 0.01) and greater (P < 0.05) daily variances in bunk visit frequency and head down duration compared with NON steers, suggesting that feeding behavior patterns were associated with the HPT-responsive phenotype. During the 28-d postchallenge period, RES steers had decreased (P < 0.05) final BW, tended (P = 0.06) to have lesser DMI, and had greater (P < 0.05) daily variances in head down and bunk visit durations compared with NON steers, which may have been attributed to their greater acute-phase protein response to the MH challenge. These results indicate that the HPT-responsive phenotype affected feeding behavior patterns and may be associated with disease resiliency in beef cattle.

USDA quality and yield grade are primary driving forces for carcass value in the United States. Carcass improvements can be achieved by making selection decisions based on the results of genetic evaluations in the form of expected progeny differences (EPD), real-time ultrasound imaging, and physical evaluation of candidate breeding animals. In an effort to advance their ability to accurately predict the breeding value of potential sires for carcass traits, the American Simmental Association launched the Carcass Merit Program as a means to collect progeny sire group carcass information. All records were extracted from the American Simmental Association database. Progeny data were organized by sire family and progeny performance phenotypes were constructed. Sire genotypes were filtered, and a multi-locus mixed linear model was used to perform an association analysis on the genotype data, while correcting for cryptic relatedness and pedigree structure. Three chromosomes were found to have genome-wide significance and this conservative approach identified putative QTL in those regions. Three hundred ninety-three novel regions were identified across all traits, as well as 290 novel positional candidate genes. Correlations between carcass characteristics and maternal traits were less unfavorable than those previously reported.

The objective of this study was to identify small molecule metabolites in a serum sample taken at entry into the feedlot that can predict performance, and animal health. One-hundred and thirty-one Angus x Simmental steers from a single ranch were sampled at a commercial feedlot in Chappell, NE. Blood samples for metabolite analysis, chute score, exit velocity, and blood lactate concentration for temperament classification were collected in addition to feedlot performance data and carcass quality measurements. The GLM and LSM procedures of SAS (SAS 9.4, 2014) were used to evaluate differences between temperament classifications. Steers were divided into three exit velocity classifications one standard deviation from the mean were classified as fast and exit velocities lower than one standard deviation from the mean were slow. Forty metabolites were quantified using 1H NMR Spectroscopy from serum. Metaboloanalyst was used to analyze serum metabolites and phenotypic values using one way- ANOVA, PCA, PLS-DA, and a permutation test to cross validate. Data were normalized and scaled. No metabolites were predictive of any of the animal health metrics collected. Five metabolites were different in exit velocity class at (P < 0.01; Methanol, Isopropanol, Lactate, Isobutyrate, and Pyruvate). Similarly, seven metabolites were different in chute score classes at (P < 0.01) (Methanol, Isobutyrate, Creatinine, Dimethly Sulfone, Hippurate, Isopropanol, and Succinate). Furthermore, several metabolites in serum at entry in the feedlot were related to carcass quality metrics; Back Fat (Urea and 2-Hydroxyisobutyrate at (P < 0.01), a trend for prediction of quality grade at (P = 0.068), carcass value (P = 0.085). The relationship between serum metabolites identified on entry into the feedlot, feedlot performance traits, and eventual carcass quality warrants further research to elucidate the roles these metabolites play during the feedlot period and in predicting carcass merit.

Fold change and FPKM data from RNAseq of Muscle tissue samples from Red-Faced Herefords of differing carcass quality collected at harvest.