Recent developments in beef carcass evaluation

The aim of this study was to assess the effects of malate salts and culture on growth performance, carcass quality, ruminal fermentation products, and blood metabolites in heifers raised under southern Europe practical farm conditions. A total of 108 Charolaise cross heifers (214 ± 27.3 kg BW and 6.4 ± 1.1 mo of age) were housed in 18 pens of 6 animals each and used in a 114-d feedlot study. There was a totally randomized experimental design, and 6 pens were assigned to each of the following experimental diets: a control (no supplementation), the control plus 4 g of disodium/calcium malate mixture per kilogram of concentrate (2.12 g malate/kg), and the control plus 0.15 g of CBS 493.94 per kilogram of concentrate (1.5 × 10 cfu/kg). The control diet consisted of wheat-barley-based pelleted concentrate (32% starch, DM basis) and full-length barley straw. Concentrate and straw were fed separately ad libitum (5% orts) in an 88:12 ratio. On Days 0, 56, and 114, ruminal fluid and blood samples were obtained from each heifer between 2 and 2.5 h after the morning feeding by ruminocentesis and tail venipuncture, respectively. Body weight, concentrate ADFI, and G:F were recorded at 28, 56, 84, and 114 d. At slaughter, hot carcass weight and yield and carcass classification were determined in 2 representative heifers per pen (12 animals per dietary treatment). Supplementation with malate salts or did not affect concentrate ADFI ( = 0.98), ADG ( = 0.74), or G:F ( = 0.50) at any time during the experiment. At slaughter, there were no differences in carcass weight ( = 0.86), classification ( = 0.18), or carcass yield ( = 0.84) among experimental groups. Also, there were no differences treatments on ruminal pH ( = 0.24), ruminal fermentation products ( = 0.69, = 0.88, and = 0.93 for total VFA, NH-N, and lactate, respectively), and blood metabolites ( = 0.96, = 0.82, and = 0.15 for glucose, urea N, and lactate, respectively). In conclusion, under the feeding and management conditions of this study, diet supplementation with malate salts or did not have any significant effects on growth performance, carcass quality, ruminal fermentation products, and blood metabolites.

Age at puberty in beef heifers can influence economic efficiency of beef production through effects on both age at first calving (2 vs. 3+ years of age) and the time of conception of heifers in their initial breeding season. An overarching factor that influences age at puberty in heifers is nutritional management during both the preweaning period and between weaning and the breeding season. Age at puberty is heritable and selection for precocious puberty in populations such as the Nelore breed has the potential to substantially influence production efficiency. Highly effective hormonal technologies exist to aid in induction of puberty in well managed heifers. Age at first ovulation and pregnancy in heifers can be substantially influenced through implementation of nutritional and/or hormonal manipulation strategies. In the long term, combinations of genetic selection, nutritional strategies, and hormonal intervention when necessary will optimize efficiency of this aspect of beef production.

In the context of modern animal husbandry technologies, one of the key factors limiting productivity and product quality is the impact of stress factors on cattle. Stress caused by climatic conditions, transportation, dietary changes and other factors leads to a decrease in feed consumption, a deterioration in immunity, a slowdown in weight gain and a deterioration in meat products, which negatively affects the competitiveness of beef in domestic and global markets. This article provides a comprehensive analysis of modern research on the use of new biologically active additives (dietary supplements) with anti-stress effect in beef production technology. The main mechanisms of action of such supplements are considered, including strengthening antioxidant protection, normalizing hormonal balance, supporting the immune system, improving the microbiota of the digestive tract and increasing the efficiency of nutrient metabolism. Special attention is paid to phytogenic components, essential oils, adaptogens, amino acids (for example, protected GABA), as well as organic trace elements and complex antioxidant mixtures. The article describes in detail the results of studies demonstrating a significant reduction in hormonal stress, an improvement in average daily gains, an increase in the immune status of animals and an improvement in the quality of meat products when using these additives. The factors influencing the effectiveness of their use are discussed, including the form of release, dosage, stage of development of animals and conditions of detention. Practical recommendations are given on the integration of anti-stress biologically active additives into the diet and technological processes of livestock enterprises, which makes it possible to increase the production efficiency and competitiveness of beef while complying with economic feasibility and safety requirements. The data obtained indicate the prospects of using anti-stress biologically active additives in a comprehensive strategy for managing the health and productivity of cattle, which opens up new opportunities for the innovative development of meat farming. The article will be useful to specialists in the field of animal husbandry, veterinary medicine, agricultural science, as well as practitioners interested in improving the quality and efficiency of beef production.

Energy Analysis of Oklahoma Rangelands and Improved Pastures

The overall efficiency of beef production is considered more highly correlated with cow–calf efficiency, viz. maternal productivity (MP), than the efficiency of other segments of the beef production chain. Recently, concerns have been raised that improvements in feedlot and carcass performance have led to a decline in MP due to the uncertainty that surrounds the relationships between production and MP traits. The Beef Cooperative Research Centre ‘Maternal Productivity’ Project examined the impact of cow genotype and nutrient intake on breeding herd productivity. This experiment demonstrated that cow body composition is influenced by genetic differences in rib fat and residual feed intake, as well as nutrient availability. Genetic differences in rib fat were shown to influence heifer pregnancy rates, observed days to calving, MP when nutrient intake is restricted and ME intake by the cow–calf unit. Weaning rate was found to account for a large portion of the variation in MP, while cow genetic background and pre-weaning nutrient availability influenced the postweaning and carcass performance of progeny. These findings demonstrate that although balancing the requirements of MP with those of other traits is not straight forward, it is of critical importance. Incorporating modelling systems into decision-support systems (DSS) offers the opportunity to integrate fragmented knowledge into decision making. Unfortunately, previous DSS have gained little traction and limited adoption due to their perceived complexity, large input-data requirements, and mismatches between outputs and the decision-making styles of producers. The development of the BeefSpecs fat calculator provides an example of how producer-measurable inputs and simple user interactions can be combined using modelling systems to develop DSS to improve MP. No single model that addressed all issues affecting MP was found in the literature. Thus, it was concluded that previous modelling systems would need to be combined to develop a suite of DSS that target-specific components of MP, such as heifer pregnancy rates and interactions between the cow herd and the nutritional environment.

Meat standards and grading

Thirty heifers were randomly sampled at five ages from each of the Hereford, Charolais, and Simmental herds at the U.S. Meat Animal Research Center to estimate association of fasting heat production (FHP) with body composition. Replicated measures of respiratory exchange were obtained for six heifers per breed at ages 2 d, 3 mo, 7 mo, 10 mo, and 14 mo using open-circuit calorimetry. Regression adjustment of FHP/live weight.75 to zero activity (AFHP) reduced the mean by 12% and variance among periods for the same animal by 42%. Daily AFHP (kcal/kg.75) was highest at 2 d (122), lowest at 10 mo (92) (P less than .01), and intermediate (103 to 106) at other ages and averaged 109, 106, and 102 for Charolais, Simmental and Hereford over all ages (P less than .05). Pooled within-age correlations of AFHP were .77 with weight of carcass (CAR) nonfat or water and .75 with live and empty body weight (EBW) but were only .13 with fat weight. Prediction of AFHP within age groups was most accurate from multiple regression on the nonfat weight in visceral organs and blood (VOB), gastrointestinal tract (GIF), head, hide, and shanks (HHS), and CAR fractions (R2 = 61%, error SD = 21.5), from regression on nonfat in CAR alone (60%, 21.6), or from regression on chemical components in each of the four fractions (59%, 22.0), relative to EBW (55%, 22.9) or its four chemical components (58%, 22.3). Partial regressions were largest for water or nonfat (P less than .01) and were negligible for fat. Importance in predicting AFHP was two to eight times greater for nonfat in CAR than in other fractions because CAR was 60 to 65% of EBW. Lean mass is clearly a major predictor of nutrient requirement that is useful to evaluate effects of body composition on the efficiency of beef production.

The article presents the results of research on the comparative assessment of the growth, development and meat productivity of calves and castrates of Kalmyk and Simmental breeds under the same conditions of feeding and maintenance and identification of ways to increase the profitability of beef production by using the physiological state of young animals. The experimental young animals received the same amount of feed by volume and the composition of the diet was the same. As a result of the conducted studies, it was found that the live weight of bulls of both breeds with their intensive cultivation exceeded the mass of castrates in all age periods. After weaning, there was no significant difference in the live weight of calves of the Kalmyk and Simmental breeds, which had a live weight of 255.6 and 253.9 kg, respectively, and by the age of 15.5 months, many bulls of both breeds reached from 500 to 520 kg. Castrates of both breeds grew less intensively. However, in the final period of fattening, they gave a high average daily increase (more than a kilogram). The Kalmyk castrati were less demanding of coarse feeds and used them better. According to the indicators of the control slaughter, it can be noted that the mass of carcasses of bulls of both breeds is the same, and castrates had such a mass of carcasses only at the age of 18 months. At the same time, the carcass mass of castrates of the Simmental breed was 7.6 kg lower than the carcass mass of Kalmyk castrates. Bulls and castrates of both breeds gave an exceptionally high slaughter yield. At the same time, animals of the Kalmyk breed have a higher slaughter yield due to the large accumulation of internal fat. An analysis of the data on the efficiency of beef production when selling one head of bulls at 15-16 months of age compared with castrates shows that the level of profitability per sold head is higher for both breeds by 1.8 and 4.3%, respectively. Thus, due to the peculiarities of the hormonal status of bulls, compared with castrates, they have an increased ability to grow, protein synthesis and reduced fat formation. However, castrates can also be grown extensively and for a longer time in less favorable conditions and receive high-quality beef, steers – only intensively and for a limited period (up to 16-18 months).

Twenty-four prenatally androgenized (PA) heifers, born to testosterone propionate-implanted cows, and 27 control (C) heifers, born to nonimplanted cows, were bred, calved, and placed in drylot pens, with calf at side, to assess the effects of PA on feedlot growth and lactational performance of heifers used in a single-calf heifer (SCH) system. Lactating heifers were fed an 85% concentrate diet, calves weaned at 117 d postpartum, and heifers slaughtered at a constant compositional end point of 1.1 cm of s.c. fat. Preweaning, PA heifers gained 22.5% faster (P < .01) and were 17.3% more efficient (P < .01) than controls. Prenatal androgenization of the heifer, however, did not affect calf growth performance. All calves gained more than 1.4 kg/d and had an average weaning weight of 159 kg at 117 d of age. Combining heifer-calf weights, PA and C pairs gained 2.88 and 2.53 kg/d, respectively. Correcting for DMI of calves, PA improved (P < .01) efficiency of beef production 10.8%. Four percent fat-corrected milk yield of PA and C heifers averaged 7.96 and 7.60 kg/d, respectively, and the percentage of milk protein and fat did not differ. Accounting for average BW, milk production, and DMI, PA and C lactating heifers should have gained 1.27 kg/d; however, gains were 137 and 127% of those predicted, respectively. Overall, pre- and postweaning, PA heifers required 10 fewer (P < .04) days on feed, gained 23% faster (P < .01), and were 16% more efficient (P < .02) than C heifers. At slaughter, PA and C heifers averaged 853 and 865 d of age, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Records on 140 individually fed cow-calf units at weaning and 137 units at slaughter were used to determine relationships between actual measures of biological cow-calf unit efficiency at weaning and slaughter and predictive measures of efficiency at those end points. The relationships among actual measures of efficiency and several traits of the calf and cow were also investigated. Data were collected at the Livestock and Range Research Station, Miles City, Montana. In this study, TDN intake of a cow was adjusted to 1 yr and of a calf from birth to 180 d of age; FEFF WEAN is defined as 180-d calf weight divided by TDN intake of the cow and calf for these periods. Predictive measures of efficiency accounted for 66 to 76% of the variation in biological efficiency of the cow-calf unit at weaning. Preweaning average daily gain and 180-d calve weight each accounted individually for 69% of the variation in cow-calf unit efficiency at weaning. Two measures of biological efficiency of the cow-calf unit at slaughter were studied. The first, FEFF LIVE, measured kilograms of live calf weight produced/kilogram of TDN consumed by the cow during the year and by the calf from birth to slaughter. Predictive formulas for this measure accounted for 41 to 56% of the variation in efficiency at slaughter. The correlation between this measure of efficiency and average daily gain from birth to slaughter was .75. The second measure of efficiency at slaughter, FEFF CARCASS, was defined as weight of lean cuts produced divided by TDN intake of the cow during the year and of the calf from birth to slaughter. Predictive formulas for this measure accounted for 49 to 66% of the variation in cow-calf unit efficiency at slaughter. Weight of lean cuts/day of age also accounted for 66% of the variation in FEFF CARCASS. The best predictive measures of cow-calf unit efficiency at weaning and slaughter included measures of metabolic calf weight and(or) cow weight in the denominator as a reflection of nutrient requirements of the cow-calf pair. However, when evaluated within a breed group, measures of growth rate seemed to be as useful as the best predictive measures in predicting cow-calf unit efficiency. These results are supportive of the methods used in performance testing programs to improve productivity and efficiency of beef production. Within a group, no significant associations between measures of mature cow size and efficiency of the pair at weaning were found. A small negative relationship was evident at slaughter. Cow-calf units with steer progeny were 5.4% more efficient at weaning than units with heifer progeny and were 5.9 and 7.7% more efficient based on the two measures of efficiency at slaughter.

The carcasses of South African pigs are classified into six groups (PORCUS) according to their calculated lean meat content and measured backfat thickness. Pigs with the highest lean meat content and lowest backfat thickness belong to the P group. Fat quality of backfat from 2107 pig carcasses, sampled within the different pork classification groups at a major South African pig abattoir, was evaluated to determine the relationship between carcass classification and backfat quality. Extracted fat was used to determine the iodine value of these samples. Significant differences in carcass characteristics and iodine value were observed between the classification groups. Improved fat quality, indicated by a lower iodine value, was associated with increased backfat thickness and decreased lean meat content. The P and O classification groups (with backfat thickness &lt;17 mm) could not conform to international standards proposed for good technological quality backfat. The C, U and S groups (with backfat between 23 and &gt;32 mm) possessed good technological quality backfat. Backfat from the R group had borderline fat quality. Correlation analyses were employed to acquire equations to describe relationships between iodine value and carcass classification data. The French classification system predicts fat quality by utilizing backfat thickness and lean meat content. It was proposed, through modification of the French system, that South African pig carcasses with a backfat thickness &gt;17 mm and a lean meat content &lt;67% would potentialy deliver good quality backfat. Results from this study indicate that carcass classification data may be used to improve the probability of selecting pig carcasses with good quality fat.Keywords: Backfat, fatty acid(s), iodine value, meat processing, South Africa, survey, swine

The European beef carcass grading scheme prioritizes meat yield over consumer eating experience, in contrast to the Meat Standards Australia (MSA) grading scheme, which is more focused on eating quality. The Italian–French beef production system, mostly characterized by young bulls and heifers imported from France and then fattened within Italian specialized fattening units, has been underexplored using the MSA grading system. This study examines the impact of animal sex on performance, MSA traits, and predicted MSA quality scores (MQ4 and MSA index) using carcasses from an Italian commercial abattoir. It also assesses how animal performance and MSA traits influence predicted beef eating quality. A Random Forest classifier demonstrated high performance with an accuracy of .98, a specificity of .99, and a sensitivity of .97 after 10-fold cross-validations, confirming key traits such as hot carcass weight, European carcass grading scheme fatness score, and general muscular characteristics as being significantly different due to sex. Entire males had greater muscle development, whereas females had notably higher MSA marbling scores, MQ4 scores, and MSA index (P &amp;lt; .05). Furthermore, categorizing the MSA index into 2 classes and applying a similar Random Forest classifier approach revealed that MSA marbling was the primary factor influencing variability of the MSA index. These findings suggest that beef cuts from females may better meet consumer expectations when using the MSA grading scheme in Europe, making them a suitable category for premium beef branding. Grading carcasses from entire male animals for sensory quality is also important, as it demonstrates their potential to produce good-quality beef with a higher lean meat yield; however, their sensory quality tends to be lower than that of heifers and this is in part reflected by their lower marbling score resulting from reduced intramuscular fat deposition.

Crossbreeding effects on beef production characteristics, growth, carcass and meat quality traits were registered on a total of 162 purebred Norwegian (NRF) dual‐purpose and crossbred bulls obtained from mating (AI) NRF dams with NRF, Aberdeen Angus, Hereford and Charolais sires. The offspring were reared in commercial farms until slaughter. Data were analysed by mixed models and adjusted to either constant carcass weight (305 kg), slaughter age (19.5 mos.) or carcass fat level (6% fat) end points. Improvements in beef production traits obtained by crossbreeding were highly dependent on the choice of sire beef breed. NRF × Charolais crossbreds had the highest daily carcass gain and carcass quality (fleshiness grading) at all end points. Crossbreeding with Aberdeen Angus and Hereford gave no growth advantages, an intermediate increase in carcass fleshiness grading and an increase in weight constant carcass fat level compared to purebred NRF. The small, significant breed differences observed for colour, flavour, tenderness and firmness were of minor importance, and revealed that substantial improvements in meat quality cannot be expected by crossbreeding the actual beef breeds with the dual‐purpose NRF breed under the present production system.

The objective of the work was to study the beef production efficiency through intensive rearing and fattening of Simmental and crossbred bull calves. The bull calves were divided into three groups of 15 animals each in order to carry out the survey. The first (control) group involved purebred Simmental bull calves. The second group consisted of young stock produced via crossbreeding Simmental cows with German Simmental beef bulls. The third group was formed from crosses of Simmental cows with Charolais bulls. The animals of the second and third groups were characterized by lower feed costs per 1 kg liveweight gain, comprising 8.5 and 8.1 EFU, respectively, while the feed utilization efficiency for the bull calves of the first group comprised 8.7 EFU. These factors affected the profitability of beef production. Thus, the level of profitability of rearing the Charolais crosses reached 20.7%, which was 6.8 and 3% higher than that in the bull calves of groups one and two, respectively. Fattening to the age of 18 months contributed to a significant increase in the carcass fat mass. Therefore, the protein-to-fat ratio comprised 1 : 084, 1 : 0.75, and 1 : 068 for the groups in ascending order of their numbers. Under intensive rearing and fattening systems, Simmental bull calves of group one gained the target beef quality up to the age of 15 months. The practice of fattening the crossbred bull calves of groups two and three up to the age of 18 months has proved that their meat gains the target protein-to-fat ratio, while the meat of bull calves of the maternal breed should be considered over-fat beef, since the fat content exceeds the standard recommendations. The intensive system of rearing and fattening the Simmental bull calves up to the age of 15 months and the Simmental crosses with the German Simmental beef breed and the Charolais breed up to the age of 18 months can ensure the production of heavy carcasses with the target quality beef.

Simple SummaryA pooled statistical analysis of seven experiments and 200 pen observations was performed to determine the impact of feeding Enogen® corn compared to conventional corn grain in beef cattle finishing diets. When the corn was compared as dry-rolled corn in diets with lower inclusion rates of distiller grains plus solubles (less than 20% of the diet), feeding Enogen® corn improved the efficiency of beef production. That response was a 4.8% improvement due to feeding Enogen® in a corn-based diet without distiller grains but was 1.8% in diets with 18 to 20% distiller grains. Feeding Enogen® corn improved the efficiency by 4.5% in diets with another common byproduct, Sweet Bran®. Cattle performance was similar for Enogen® and conventional hybrids when processed and fed as high-moisture corn. Feeding Enogen® corn improves the gain efficiency of finishing cattle compared with conventional corn when fed as dry-rolled corn in diets with less than 20% distillers or diets that include Sweet Bran® feeds.The objective of this pooled statistical analysis was to evaluate Syngenta Enogen® Feed Corn (EFC) versus conventional corn (CON) when fed as either dry-rolled corn (DRC) or high-moisture corn (HMC) for effects on finishing beef cattle performance and carcass characteristics. Corns were evaluated in diets with byproduct inclusion rates of 0, 15, 18, 20, and 30% distiller grains or 25 and 35% Sweet Bran® (a commercial corn gluten feed product). Seven trials (n = 1856) consisting of 200 pen means comparing 26 diet treatments were analyzed using regression in a pooled analysis. When EFC was processed as DRC, the gain efficiency (G:F) improved compared with CON, but the response to feeding EFC decreased from a 4.8% improvement to no improvement compared to CON as distiller grains increased from 0 to 30%, but was significantly improved due to feeding EFC in diets with 0 to 18% distiller grains. Feeding cattle EFC as DRC increased the average daily gain (ADG) and G:F by 4.5% compared with CON corn in diets containing Sweet Bran®. No improvements in animal performance were observed when cattle were fed EFC compared to CON when processed as HMC in any situation. Feeding Enogen® corn improved the gain efficiency of finishing cattle compared with conventional corn when processed as dry-rolled corn and fed in diets with less than 20% distillers or diets that include Sweet Bran®.