Beef Carcasses Research Articles

Prevalence, Characterization, and Antimicrobial Susceptibility of Listeria monocytogenes from Raw Beef and Slaughterhouse Environments in Korea.

The prevalence of Listeria monocytogenes in raw beef and in slaughterhouse environments was investigated from April 2019 to February 2020. Three hundred raw beef samples were purchased from 50 retailers and 10 restaurants (5 samples per source). One hundred and thirty-four samples from slaughterhouse environments were collected by swabbing (10 × 10 cm) the surfaces, gloves, splitting saw, and drains. L. monocytogenes was detected and identified according to the method described in ISO 11290-1, and confirmed by 16S rRNA sequencing. L. monocytogenes was detected in raw beef (2/300, 0.7%), gloves used in carcass splitting (6/21, 28.6%), the splitting saw (1/18, 5.6%), and the drain zone (1/15, 6.7%). All isolates were serotype 1/2a or 1/2c, based on screening using multiplex PCR-based serogrouping assay and serotyping kit for O-H antigens. Pulsed-field gel electrophoresis (PFGE) following ApaI digestion of eight PFGE pulsotypes and four PFGE groups were identified. Biofilm formation analysis using Crystal Violet staining revealed the highest biofilm formation in strain LM-16, followed by D190613. Although L. monocytogenes isolates were susceptible to most antimicrobials, some resistance to penicillin (8/15, 53.3%) and tetracycline (2/15, 13.3%) was observed. Through PFGE, G190426, G190829, and G200210 isolated from the same location in this study were genetically homologous similar to the LM-16 strain, previously isolated from beef carcass in 2006. These results suggest that LM-16 has been continuously present in biofilms in the slaughterhouse environments since 2006. Our study indicates that L. monocytogenes contamination in raw beef could consistently occur during beef processing in slaughterhouse environments through contact with gloves, splitting saws, and drains.

Характеристика замороженої яловичини за біохімічними і мікробіологічними показниками

Goal. To assess methods of storing frozen beef according to microbiological and chemical indicators. Methods. Microbiological and biochemical studies of fresh and frozen beef aiming at the determination of the indicators of freshness and microbiological safety were carried out by standard and generally accepted techniques. Results. It was found that the number of mesophilic microorganisms on fresh beef carcasses (24 h) was 12.7 times higher as compared to the number of psychrotrophic microorganisms. During 8-months’ storage of beef in a frozen state (–12°C) the number of mesophilic aerobic and optional anaerobic microorganisms decreased 7.8 times, Enterobacteriaceae — in 16.8, psychrotrophic microflora — only in 1.6 times. At the same time, fungal microflora for these storage modes increased 1.7 times. When storing beef at a temperature of –20...–25°C for 14 and 18 months, the gradual dying of microflora on its surface was revealed. At the same time, the amount of mesophilic and coliform microflora decreased on a larger scale — about 10 and 24 times, respectively. The number of psychrotrophic microflora thus decreased only 1.8 times against the initial amount, and the fungal one remained unchanged. Within 8-months’ storage of beef at –12°C deterioration was revealed of indicators and its freshness. At the same time, for storage of meat at –20...–25°C for 14 and 18 months, the presence of volatile fatty acids indicates its doubtful freshness. Also, the growth of products of peroxide oxidation of lipids is fixed in beef with long-term storage at –12°C. Conclusions. When storing beef in a frozen state at a temperature of –12°C for 8 months the development of mesophilic and psychrotrophic microflora is stopped. The most detrimental temperature of –12°C influences mesophilic and coliform bacteria. At the same time, the propagation of fungal microflora on the surface of the carcass is fixed. When storing beef at –20...–25°C for 14-18 months the microflora on its surface did not multiply, but gradually died. Within 8-months’ storage of beef at -12°C the deterioration was revealed of biochemical indicators of its freshness. At the same time, for storage at – 20...– 25°C for 14 and 18 months, beef had questionable freshness only by the content of volatile fatty acid.

Tenderness and Color Stability of Beef Longissimus Thoracis and Semimembranosus Steaks From Carcasses With Varying Hot Carcass Weights

Our objectives were to determine how beef hot carcass weights relate to temperature and pH decline, Warner-Bratzler shear force, and objective color of steaks from the longissimus thoracis and semimembranosus. Beef carcasses (N = 59) were selected at a commercial plant based on hot carcass weight and separated into either light- (< 363 kg), medium- (364–407 kg), or heavy-weight (> 408 kg) groups. Temperature and pH in the longissimus thoracis and semi-membranosus muscle were measured for 24 h. After carcasses were chilled for approximately 24 h, ribeye area, 12th rib backfat, kidney, pelvic, and heart fat percentage, marbling score, and USDA final yield grade were collected. Ribeye rolls (Institutional Meat Purchase Specification 112a) and inside rounds (Institutional Meat Purchase Specification 160a) were collected at the plant and transported to the North Dakota State University Meat Laboratory. Data were analyzed using the mixed procedure of SAS version 9.4 (SAS Institute Inc., Cary, NC) with carcass weight class as the fixed effect and day of collection as random. Longissimus thoracis muscle temperature of light-weight carcasses was lower at 4 h compared with heavy-weight carcasses (P = 0.02). Semimembranosus muscle temperature of light- and medium-weight carcasses was lower at 24 h compared with heavy-weight carcasses (P < 0.0001). There were no differences in pH decline (P ≥ 0.16) among carcass weight groups. There were no differences in fat thickness; kidney, pelvic, and heart fat percentage; or marbling score (P ≥ 0.12) among carcass groups. There were no differences in drip loss, cook loss, or Warner-Bratzler shear force in either longissimus thoracis or semimembranosus muscles (P ≥ 0.10) among carcass groups. Objective color measurements found that steaks from heavy-weight carcasses were redder than steaks from light-weight carcasses (P ≤ 0.02). Hot carcass weight group did not influence most meat quality attributes of steaks with the possible exception of color.

MALDI-TOF MS Based Typing for Rapid Screening of Multiple Antibiotic Resistance E. coli and Virulent Non-O157 Shiga Toxin-Producing E. coli Isolated from the Slaughterhouse Settings and Beef Carcasses.

Background: The emergence of multiple antibiotic resistance (MAR) Escherichia coli (E. coli) and virulent non-O157 Shiga toxin-producing Escherichia coli (STEC) poses a growing concern to the meat industry. Non-O157 STEC strains including O26, O45, O103, O111, O121, and O145 have been implicated in the occurrence of bloody diarrhea and hemolytic uremic syndrome in humans. This research assessed prevalence, matrix-assisted laser desorption/ionization-time of flight mass-spectrometry (MALDI-TOF MS) protein mass-spectra profiles, multidrug-resistance traits, polymerase chain reaction detection of virulence, and antibiotic-resistance genes of E. coli isolated from beef carcasses and slaughterhouse environments. Methods: A total of 180 convenience sponge samples were collected from two different sources-specific parts of beef carcasses and surfaces of the processing environment at the slaughterhouse of Ha′il, Saudi Arabia between September and November 2020. MALDI BioTyper and phylotype-based identification methods accurately identified and classified the samples as belonging to the genus belonging to the Escherichia coli domain of bacteria (NCBI txid: 562). Results: Expected changes were seen in the mass peak spectrum defining nine closely related isolates and four unrelated E. coli isolates. Serological typing of E. coli revealed enterotoxigenic E. coli O166 (19.10%); enteropathogenic E. coli O146 (16.36%) and O44 (18.18%); enterohemorrhagic E. coli O111 (31.18%) and O26 (14.54%). Forty-five percent of examined E. coli were resistant to seven antimicrobials; 75% of 20 selected isolates were resistant to three or more antimicrobials. phoA and blaTEM genes were detected in all selected E. coli isolates. Conclusion: This study confirmed the efficiency and validity of Matrix-assisted laser desorption/ionization time of flight mass-spectrometry in screening for multi-drug resistant E. coli isolated from slaughterhouse derived beef carcasses in Ha’il, Saudi Arabia. We contributed by revealing the distinction between related and non-related strains of E. coli in livestock. The findings in this study can inform improved policy development decision making and resource allocation related to livestock processing regarding antimicrobial use in food animals and rapid screening for effective multiple antibiotic resistance E. coli and virulent non-O157 STEC control in the slaughterhouses.

Using Bioelements Isotope Ratios and Fatty Acid Composition to Deduce Beef Origin and Zebu Feeding Regime in Cameroon.

The purpose of this study was to address the lack of knowledge regarding the stable isotopic composition of beef from zebu cattle reared in tropical Africa. Sixty beef carcasses belonging to the most common zebu breeds (Goudali, white Fulani, and red Mbororo) were selected and classified according to their subcutaneous fat color (white, cream or yellow). The stable isotope ratios of five bioelements—H, O, C, N, and S—in muscle fractions and the fatty acids composition were analyzed. Zebu meat from Cameroon shows peculiar δ13C values, related to the almost exclusive intake of grazed tropical grasses with photosynthetic cycle C4. It also shows δ2H and δ18O values higher than those reported in other areas of the world and correlated with the isotopic composition of animal drinking water. The white subcutaneous fat (“white type”) zebu showed higher δ2H and lower δ13C than the “yellow type”, that is correlated with a higher content of polyunsaturated fatty acid (PUFA) and a lower amount of saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA). Multielement analysis seems to provide promising results for tracing the regional origin of Cameroon beef and some aspects of the livestock system, such as the nutritional status of the animals.

Evaluation of Bacterial Contamination of Beef Carcasses in Namwala and Lusaka Districts of Zambia

Abattoirs have been purported to be ideal areas were possible microbial contamination of meat products is likely to occur. Food of animal origin, mainly beef, has been identified as a source of dietary protein for humans albeit it being a source of food-borne diseases including zoonoses. This study was carried out to evaluate bacterial contamination and the risk factors associated with contamination of beef carcasses during processing. A total of four abattoirs were sampled within three months with one in Namwala and three in Lusaka districts. A total of 314 beef carcass surface swabs were obtained from the neck region by swabbing the carcasses, immediately after evisceration and after washing. Results The results of mean total viable counts (TVC) of carcass contamination were enumerated as the mean log from 4.7 Log10 cfu/cm2 in an abattoir where Hazard Analysis and Critical Control Points (HACCP) was practiced to 5.8 Log10 cfu/cm2 without HACCP. Bivariate analysis showed a significant difference in carcass contamination when town abattoirs (Lusaka) were compared with rural ones (Namwala); χ2 = 43.87, P < 0.0001. Multiple logistic regression analysis identified poor hygiene practices, the absence of antemortem inspection, and lack of Hazard Analysis and Critical Control Points (HACCP) implementation as significant factors associated with carcass contamination. Conclusion A high microbial load as determined by the Total Viable Count is an indicator that beef is being produced under poor abattoir hygiene conditions. Therefore, beef carcasses with high bacterial loads are potential sources of foodborne pathogens leading to foodborne disease and hence there is need for advocating for good hygiene practices in the abattoirs.

Association between animal welfare indicators and microbiological quality of beef carcasses, including Salmonella spp., from a slaughterhouse in Ecuador.

Background and Aim:Pre-slaughter management and slaughter operations are considered critical factors for animal welfare and meat quality. Previous studies have found poor animal welfare management at municipal slaughterhouses in Ecuador, and little is known about how this affects the microbiological quality of the meat. Therefore, the aim of the study was to analyze the association of the microbiological quality of beef carcasses and animal welfare indicators in a municipal slaughterhouse in Ecuador.Materials and Methods:Data for 6 months were collected from a municipal slaughterhouse in Ecuador. Five trained researchers were strategically located along the slaughter process. A total of 351 animals were observed with regard to welfare indicators, and their carcasses were sampled to evaluate microbiological quality. Antemortem (slipping, falling, and vocalization) and postmortem animal welfare indicators (bleed interval, pH, temperature, and bruises) were measured. To determine the total aerobic bacteria (TAB) and Escherichia coli counts and the presence of Salmonella spp., we collected samples by swabbing four different points of each carcass. The association between microbiological quality and animal welfare indicators was studied using univariate and multivariate logistic regressions.Results:The mean TAB count was 5.3 log CFU/cm2, and the mean total count of E. coli was 2.4 log CFU/cm2. Salmonella spp. were isolated in 3.1% of the carcasses. An electric goad was used in all animals, 19.1% slipped at least once, and 19.9% vocalized. The mean pH of the carcasses was 7.2, and 79.2% of carcasses had bruises. Multivariate analysis showed that Salmonella spp. and the TAB count were associated with pH and the number of bruises (p = 0.01 in both cases).Conclusion:Although there was non-significant association between the majority of animal welfare indicators and microbiological quality, the poor management affecting animal welfare and carcass hygiene are worrisome.

Effects of Antimicrobial Interventions on Indicator Organisms during Beef Carcass Dressing

Beef slaughter establishments employ many interventions to help minimize the occurrence of pathogens in their products. This study explored the effectiveness of various common interventions on microbial load using the results of the Beef-Veal Carcass Baseline Survey conducted in 2014 to 2015. The Food Safety and Inspection Service analyzed swab samples taken from 1,135 carcasses at 139 establishments. These included paired samples from post-hide removal (before evisceration) and prechill (after evisceration). Samples were tested for pathogens (Salmonella and Shiga toxin-producing Escherichia coli) and indicators (E. coli, Enterobacteriaceae, coliforms, and aerobic count [AC]). The sample size for pathogen-positive samples was small, impeding the establishment of a direct correlation between interventions and pathogens. However, we observed associations between pathogen-positive rate and log AC, indicating similar intervention effectiveness of pathogens and indicators in this study. Generally, the use of interventions reduced indicator concentrations. Each intervention produced a range of effectiveness, suggesting that how interventions are applied may be as important as which interventions are applied. The range of effectiveness for single interventions was a 0.4- to 1.9-log AC reduction; for multihurdle interventions, it ranged from 1.6- to 2.9-log AC reduction. The results of this study may be used by slaughter establishments to help identify effective intervention options for pathogen reduction.

Objective carcass grading for bovine animals based on carcass length

ABSTRACT The aim of the study was to evaluate performance for beef carcass grading using a novel semi-automatic method compared to human classifiers. The novelty was measuring carcass length as a predictor. The grading is given as conformation and fat cover as defined by the EUROP classification system. A training set was used to fit the model with predictors based on weight, age, breed and sex, in addition to length. Prediction performance was evaluated for a test set including carcasses graded by Norwegian classifiers, and a separate test set for carcasses graded by international classifiers. The precision for conformation was high (Pearson correlation ≥ 0.94) for both test sets, but the precision for fat cover was lower (Pearson correlation range 0.30–0.91). High correlation for conformation, together with low bias estimates, provides indication that the objective method is equipped to replace the previous human classifier system for conformation in Norway.

Are Marbling and the Prediction of Beef Eating Quality Affected by Different Grading Sites?

For the European abattoirs, the preferred carcass grading site is at the fifth rib, and cutting at the tenth rib as in Australia could lead to a lower economic value of the carcass. Therefore, the objective of this study was to compare the grading scores of marbling and the meat and fat color on Musculus longissimus thoracis et lumborum (LTL) at the fifth and the tenth thoracic vertebrae. The consequences on the prediction of beef eating quality using the Meat Standards Australia (MSA) grading scheme were also evaluated for cull cows, which produce the majority of beef consumed in France. Carcasses from 208 French cattle, mainly Limousine cows, were graded according to the Australian Beef Carcase Chiller Assessment System (ABCAS) used for the implementation of the MSA system. The results indicate that there was no significant difference in the marbling score, between the fifth and the tenth ribs and hence in the MSA index and in the Global Quality [meat quality (MQ4)] scores calculated from marbling values from either the fifth rib or the tenth rib. However, the meat color at the tenth rib was significantly darker than that at the fifth rib (p < 0.01), and the fat color at the tenth rib was significantly yellower than that at the fifth rib (p < 0.001). The results of this study suggest that the grading of marbling can be conducted on M. LTL at the fifth thoracic vertebrae for routine use of the MSA system in France and, more generally, in Europe. However, further investigation and adjustment would be needed for other critical MSA scores (such as rib fat thickness) while respecting the European carcass quartering practices.

Nix Pro Color Sensor provides comparable color measurements to HunterLab colorimeter for fresh beef.

The HunterLab MiniScan (HunterLab) colorimeter is used in meat quality research worldwide for measuring meat color; however, the Nix Pro Color Sensor (Nix) could be a less expensive alternative that is easier to operate. Therefore, the objective of this study was to compare the two colorimeters to objectively evaluate fresh beef color. Longissimus thoracis muscle from one side of A maturity beef carcasses (n = 200) was evaluated using both the HunterLab (3 technical replicate scans) and Nix (3, 5, 7, and 9 technical replicate scans) colorimeters. The correlation between the HunterLab and Nix for L* (lightness), a* (redness), and b* (yellowness) values ranged between r = 0.80 to 0.85 and the Bland Altman Limits of Agreement analysis indicated good agreement between the Nix and HunterLab colorimeters for all the color parameters. These results indicated that the Nix colorimeter could be a viable alternative for HunterLab colorimeters.

Classification of Southern Australian Grass- and Grain-Fed Beef

Enhancing transparency through the beef production supply chain using objective measurements is crucial for maintaining the premium price of Australian beef products. A four-class model has been developed using Raman spectroscopy for beef cattle sourced from four different production systems including long- and short-term grain-fed and grass- and grass-supplemented-fed cattle with an F1 score of 92%, 88%, 98% and 100%, respectively. A two-class model for grain- and grass-fed cattle showed 98.5% and 97.1% correct classification. Both models were developed using a dataset of 404 calibration samples and 101 test samples which resulted in a total of 6 and 2 misclassified samples in the four- and two-class models, respectively. Fatty acids were also utilised to separate samples by principal component analysis (PCA), and loadings revealed samples that could be separated by the concentration of omega-3 polyunsaturated fatty acids. A discriminant analysis of fatty acid data yielded a classification accuracy of between 88 and 100% of beef carcases according to production system. Thus, classification utilising Raman spectroscopy provided a reliable method to discriminate between cattle finished by different feeding systems.

Biochemical Factors Affecting East Asian Consumers’ Sensory Preferences of Six Beef Shank Cuts

The objective of this study was to evaluate biochemical factors affecting Warner-Bratzler shear force (WBSF) and East Asian consumers’ eating preferences of 6 different beef shank cuts cooked by moist heat. Six different beef shank muscles were collected from 12 USDA Choice beef carcasses (N = 72). Shank cuts from the left sides were cooked with moist heat and used for East Asian consumer sensory evaluation and WBSF, and shank cuts from the right sides were left uncooked and used for biochemical analysis and visual panels utilizing the same group of consumers. A correlation analysis was conducted to determine the driving factors that contributed to WBSF and East Asian consumers’ overall liking for beef shanks. Biceps brachii and flexor digitorum superficialis-pelvic received the greatest sensory overall liking, with deep digital flexor from the foreshank having the lowest scores (P &amp;lt; 0.01). Deep digital flexor from the foreshank had the greatest WBSF value, most cooked collagen content, and greatest insoluble collagen percentage as well as the greatest raw and cooked pyridinoline (PYD) densities among all the beef shank cuts (P &amp;lt; 0.05). For visual overall liking, shank cuts at approximately 700–750 g such as biceps brachii and extensor carpi radialis received the highest ratings (P &amp;lt; 0.01), and consumers indicated that there was no visual difference in surface color among the shank cuts (P &amp;gt; 0.10). Correlation analysis showed that cooked collagen content and insoluble collagen percentage as well as raw PYD densities had positive correlations with WBSF (P &amp;lt; 0.05) and negative correlations with consumer overall liking (P &amp;lt; 0.01). Surprisingly, collagen content from uncooked shank cuts did not have a direct relationship with consumers’ overall liking nor with WBSF. The results demonstrated that raw PYD density may be a great indicator for cooked beef tenderness in beef cuts with a high concentration of connective tissue prepared with moist heat cookery.

Effect of pre-slaughter fasting duration on physiology, carcass and meat quality in beef cattle finished on pastures or feedlot

Pre-slaughter fasting duration affect blood parameters related to stress and metabolism, decrease live and carcass weights and impact beef quality of cattle. In three experiments, 1100 steers and heifers, finished on feedlot or on pasture, were evaluated to assess the influence of the site and duration of fasting before slaughter on physiological, carcass and meat quality traits. Cattle were allocated to one of two fasting duration - long (23–29 h) or short (2–6 h) – and to one of two sites of fasting– farm or abattoir. All animals had access to water ad libitum until slaughter, except during transportation. Cattle were assigned to two (long fasting on abattoir/normal lairage time, short fasting on farm/minimal lairage time) or three (long fasting on abattoir/normal lairage time, short fasting on farm/minimal lairage time, long fasting on farm/minimal lairage time) treatments. Seventeen slaughters were considered in a randomized complete block design. There was no effect of the site of fasting on any variable. Cattle with short fasting duration had higher carcass weights and water consumption than those under long fasting duration. Haematocrit, globulin, total protein, and lactate dehydrogenase at the time of slaughter increased with fasting duration. There was no effect of the duration of fasting on blood ions, meat quality traits, urine pH, liver weight and volume, and skin dry matter. A reduction in the fasting duration returned to farmers and abattoirs 1.2% additional kilograms of carcass, suggesting an improvement in animal welfare according to a better hydration level of cattle at the time of slaughter.

Methodology to identify candidate genes from beef carcass traits at weaning: A pilot study

The goal of the work reported herein was to investigate if a new methodology could provide gene expression profiles of brachiocephalicus muscle tissue from young steers and to compare this genetic expression with carcass traits determined at slaughter to identify potential candidate genes. Tissue samples were collected from steers using a fine needle biopsy from muscle in the neck region at weaning. Muscle tissue was removed using the Dunn Biopsy method, and RNA was extracted for sequencing and transcriptomic analysis. Animal groups for data analysis were designated using marbling score codes (MSC) established from carcass grade at slaughter, which identified DNER, PCBD1 and BGN genes associated with adipose; muscle genes included MAP7, PDE1B, and ADAMTS2; tenderness genes identified were FMO2 and ZKSCAN2; and marbling genes RPTN, DNER, and CACNA2D2. These results indicate muscle biopsies may yield complementary information associated with carcass traits to the current industry standards. Application of this technique may provide insight to the identification of candidate genes that could improve production decisions, increase accuracy of prediction from transcriptomic profiling, and ultimately speed genetic progress.

Lean meat yield estimation using a prototype 3D imaging approach

Lean Meat Yield (LMY, %) of carcass is an important industry trait, which currently is not routinely measured in Australian beef abattoirs. Objective on-line technology to determine LMY is key for wider adoption. This paper presents a proof-of-concept approach for estimating the LMY of beef carcasses from the 3D information provided by RGB-D cameras. Moreover, a specifically designed on-line data acquisition system for abattoir applications is presented, consisting of three cameras moving on a scanning rig to generate 3D carcass side reconstructions. The hindquarter is then segmented consistently across all the 3D models to extract curvature information and LMY estimated via non-linear regression based on Gaussian Process models. Sides from 119 carcasses at two different commercial abattoirs were used to evaluate this approach. Results from this preliminary study (RMSE = 3.91%, R2 = 0.69) using curvature, P8 fat and HSCW indicate that 3D imaging of beef carcasses is a viable and relatively accurate technology to estimate LMY.

A longitudinal study: Microbiological evaluation of two halal beef slaughterhouses in the United States

Most evidence about the hygienic condition of halal food is derived from studies conducted in Muslim-majority countries, not western countries. Because context of practice is different in Muslim-majority countries, it is difficult to apply these findings to western countries, such as the United States. We aimed to determine the hygienic condition of beef carcasses and environmental surfaces in two U.S. halal beef slaughterhouses over a 12-month period. Each month between November 2016 and October 2017 samples were collected [N = 432 carcass samples (pre- and post-evisceration)] and 59 surface samples (slaughter hall floor, brisket saw, and offal table). All carcass and surface samples were analyzed for detectable levels of four indicator organisms -- aerobic plate count (APC), Enterobacteriaceae count (EC), total coliform count (TCC), and generic Escherichia coli (ECC). All indicator organisms (APC, ECC, TCC, and EC) in samples collected from both plants were within acceptable limits based on USDA microbiological guidelines of beef carcasses. Significant differences (P < 0.001) in the detectable levels of indicator organisms between pre- and post-evisceration were shown in plant B but not plant A. A significant difference (P < 0.01) in detectable levels of all indicator organisms was shown between winter and summer. Levels were higher during the summer (June–September) in pre-evisceration samples at both plants compared to samples collected in the winter (December–February). These findings can be used to inform food safety interventions targeting halal beef slaughter operations in the United States.

Environmental impact of primary beef production chain in Colombia: Carbon footprint, non-renewable energy and land use using Life Cycle Assessment

In Colombia, the beef production chain accounts for approximately 11.6 million cattle heads and annually produces 933 million kg of the beef carcass. There are no life cycle assessment (LCA) studies that have evaluated the environmental performance of Colombian beef systems. The present study aimed to estimate the carbon footprint (CF), non-renewable energy use, and land use of 251 cow-calf and 275 fattening farms in Colombia. The study also aimed to identify the main hotspots of adverse environmental impacts and propose possible mitigation options and their cost-effectiveness. The impact categories were estimated using the 2006 IPCC and the 2019 Refinement to 2006 IPCC guidelines, databases, and locally estimated emission factors. The functional units used were 1 kg fat and protein corrected milk (FPCM) and 1 kg live weight gain (LWG), leaving the farm gate. Three methods of allocating environmental burdens to meat and milk products were applied: economic, energy, and mass allocation. The adoption of improved pastures was considered a mitigation measure, and an economic assessment was performed to estimate the relative cost-effectiveness of its establishment. A principal component multivariate analysis and a Hierarchical Clustering on Principal Components were performed. The economic allocation method assigned a greater environmental burden to meat (83%), followed by energy content (80%) and mass production (73%). The largest sources of GHG emissions were enteric fermentation and manure deposited on pasture. Both cow-calf and fattening systems had a cluster of farms with better productivity, pasture and cattle management practices, and environmental performance. The CF for meat could be reduced by 33 to 56% for cow-calf and 21 to 25% for fattening farms, by adopting improved pastures. Therefore, our results suggest that GHG emissions can be reduced by adopting improved pastures, better agricultural management practices, efficient fertilizer usage, using the optimal stocking rate, and increasing productivity.

Physicochemical and histochemical characteristics of bovine longissimus lumborum muscle defected as muscular steatosis (massive adipocyte infiltration)

To understand muscular steatosis observed in beef carcasses, physicochemical and histochemical characteristics were compared between abnormal (massive fatty replaced) and normal regions of beef striploin. Fat content in the abnormal region (48.02%) was approximately twice than that in the normal region (22.01%). However, fatty acids did not show significant (P > 0.05) differences in their compositions between the two regions. Tenderness was significantly (P < 0.05) higher in the abnormal region. However, other meat quality traits were not significantly (P > 0.05) different between the two regions. Massive accumulation of adipocytes was accompanied by muscle fiber atrophy regardless of muscle fiber types. Without a change in total muscle fiber density, oxidative fiber composition was significantly increased, whereas glycolytic fiber composition was decreased (P < 0.05). These findings suggest that adipogenic transdifferentiation and muscle fiber type switching can occur within the muscle due to muscular steatosis.

Bacteria contamination of surfaces and facilities at the ultra-modern abattoir Ilorin, North Central, Nigeria

Abattoir plays a major role in the processing of meat consumed by the public and its involvement in public health safety cannot be overemphasized. This study was conducted to assess the bacterial load on beef carcasses and the hygiene status of the slaughterhouse environment and facilities at the ultramodern abattoir in Akerebiata, Ilorin, Nigeria. Assessment of microbial load was carried out using Standard Plate Count (SPC) and Total Coliform Count (TCC) on environmental swabs and meat contact surfaces (n = 231), water (n = 16) and red meat (n = 14). Significant differences and association between samples were determined using Tukey's Multiple Comparison Test and Carl Pearson Correlation Matrix, respectively, on GraphPad Prism with p &lt; 0.05 considered as significant. Generally, the SPC and TCC for all samples exceeded the acceptable limits for meat and potable water set by WHO, CDC, and EU regulations. The floor had the highest mean count for SPC (8.66 ± 8.24 log cfu/cm2) and TCC (6.02 ± 5.85 log cfu/cm2). Water sourced from the borehole had no significant count for coliform as opposed to the water from the well (4.43 ± 4.32 log cfu/ml). There was a significant association between the contamination levels of butchers’ hands and processed meat (p &lt; 0.05). There is high level of bacterial contamination as indicated by the findings of this present study. This study further reiterates the public health importance of good management and hygiene practices in the meat processing chain for quality and consumer safety.