Colour of bovine subcutaneous adipose tissue: A review of contributory factors, associations with carcass and meat quality and its potential utility in authentication of dietary history

Effect of residual feed intake on meat quality in fattening Charolais bulls fed two contrasting diets

The selection of more efficient animals for breeding is of both economic and environmental interest to the industry. The aim of this study was to evaluate the influence of the animals' residual feed intake (RFI) ranking in interaction with the type of diet on the meat quality of Charolais beef cattle. Indeed, several biological mechanisms are associated with RFI, especially when animals are fed high starch-diets. It is therefore possible that quality parameters may show greater changes due to RFI in the context of high starch diets compared to high forage diets. An 84-day feed efficiency trial followed immediately by a second 112-day feed efficiency trial was conducted with a total of 100 animals fed either maize- or grass-diets for 196-days. At the end of the 84-day period, the 32 most divergent RFI animals (16 extreme RFI animals per diet, 8 RFI+ and 8 RFI-) were identified. They were slaughtered after 112-days of finishing. The Longissimus thoracis was characterised in terms of nutritional and sensory quality. RFI had no effect on lab colour, muscle shear force, total fat, fatty acid ratios and most of the total fatty acid content (especially n-3) irrespective of the diet. However, more efficient animals (RFI-) showed higher CLA contents compared to less efficient animals (RFI+) regardless of the diet and also a lower n6/n3 ratio only in animals fed the maize diets. Diet also had a significant effect on lipid and FA content as well as on FA composition.

Markers for meat provenance and authenticity with an account of its defining factors and quality characteristics - a review

Provenance is becoming increasingly important in meat supply chains as it lends products higher perceived quality. However, its precise definition and interpretation along with its associated characteristics factors have remained somewhat elusive. This review meticulously defines meat provenance while dissecting the essential factors and associated quality attributes that constitute its essence and are subsequently employed to establish pertinent markers for provenance. Meat provenance emerges as a multi-dimensional construct stemming from the adept management of a constellation of factors relating to geographical origin, farm production system, traceability, and authenticity. Through intricate interactions, these factors unveil innate originality that not only forges a distinct reputation but also imparts a unique typicity to the meat product. Gaining insights into a meat product's provenance becomes attainable by scrutinizing its pertinent composition and organoleptic quality traits. Trace elements and stable isotopes stand out as provenance markers, forging a direct connection to both geographical origin and dietary sources. While somewhat less direct in linkage, other markers such as plant biomarkers, fatty acid composition, pH levels, flavour and aromatic compounds along with organoleptic characteristics contribute to the overall understanding of provenance. Additionally, the identification of animal species and breeds serves as key markers, particularly in the context of protected geographical indications. The study findings are useful for the various stakeholders of how the information for meat provenance can be linked with intrinsic and extrinsic factors for meat quality and protecting the integrity of the supply chain with special reference to traceability and authenticity. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The Effect of Festulolium Silage-Based Diets on the Content of Tocopherols, β-Carotene and Retinol in Meat from Young Rams

This study analyzed the chemical composition and the β-carotene, tocopherol and retinol content of meat (musculus longissimus lumborum, musculus gluteus maximus) from young rams fed different silage-based diets. The animals were divided into four groups depending on the type of silage in the feed ration (hybrid ryegrass, Festulolium cv. Becva, Festulolium cv. Felopa, Festulolium cv. Paulita). The concentrations of the examined lipophilic compounds were measured via high-performance liquid chromatography (HPLC). Animals fed a diet based on ryegrass silage had the highest intakes of α-, β-, γ- and δ-tocopherol and total tocopherols (p < 0.01). Muscles of rams fed Festulolium silage-based diets contained more tocopherols (p < 0.01) and retinol (p < 0.01 in m. g. maximus; p = 0.053 in m. l. lumborum) than the meat of animals receiving hybrid ryegrass-based diets. The highest amounts of tocopherols (p < 0.01) and retinol (p < 0.01 in m. g. maximus; p = 0.053 in m. l. lumborum) were found in meat from rams fed rations based on silage made from Festulolium cvs. Felopa and Paulita. The analysis revealed a positive correlation between the intake of tocopherols and the α-tocopherol content of meat (r = 0.99), as well as between the β-carotene intake and the retinol content of meat (r = 0.92 in m. l. lumborum; r = 0.91 in m. g. maximus).

Forage based diet as an alternative to a high concentrate diet for finishing young bulls - Effects on growth performance, greenhouse gas emissions and meat quality

Two groups of 8 individually housed young crossbred-bulls, in the finishing period, were used to test the effect of a Total Mixed Ration diet with high forage content (54% DM), low starch content (14% DM), supplemented with sunflower seeds (10% DM) (HFS) on growth performance, carcass and meat quality, fatty acid profile and carbon footprint, with reference to a conventional concentrate-based (90% DM) (Control) diet. The experiment lasted 64 days before slaughter. During the experiment, feed intake was monitored daily and live weight every 14 days. Individual CH₄ emissions were assessed at 16-days intervals, using a GreenFeed for Large Animal unit. Feed intake and feed conversion ratio were higher for HFS diet, but average daily weight gain and feeding costs were similar for the two diets. Dressing percentage was reduced with HFS diet. The HFS increased redness, yellowness and Chroma of subcutaneous fat, but did not compromise commercial value of the carcasses. Meat colour, shear force, or sensory parameters were not affected by diet. The HFS diet allowed a healthier FA profile, due to the higher proportions of 18:3n-3, t11-18:1 and c9,t11-18:2 and the lower proportion of t10-18:1. The HFS diet did not reduce the carbon footprint in the finishing period of young bulls, due to increased digestive CH₄ emissions. The results of this experiment showed that the HFS diet can be an alternative to the conventional diets used in finishing young-bulls. Although it may result in a slight reduction in animal performance, it has a strong impact on reducing dependence on inputs from outside the farm.

A South African beef quality survey

In this study a survey of various meat quality characteristics of beef loin cuts was conducted in the City of Tshwane Metropolitan Municipality (Gauteng Province of South Africa) to determine the variation and consistency of beef quality of products purchased over time. Four hundred and twenty beef loin samples were collected on 20 occasions over 308 days from 13 outlets of 2 supplier types (butcher and supermarket). Packaging type, label information and price were considered for the evaluation of meat tenderness, colour, cooking loss, tissue composition and steak thickness. The results demonstrate that large variation in characteristics relevant to consumers' choice and satisfaction among and within different products sold as porterhouse steak in South Africa. In particular, muscle tenderness varied (P < 0.0001) across the 20 products and also showed significant inconsistency over the 20 purchasing events for certain products.

Can botanically-diverse pastures positively impact the nutritional and antioxidant composition of ruminant meat? - Invited review

A desire for more sustainable pasture-based ruminant feeding systems has led to growing interest in utilising botanically-diverse pastures (BDP) over monoculture pastures. Research suggests that, from a human consumption viewpoint, grass-based ruminant feeding leads to more nutritionally desirable fatty acid (FA) and antioxidant concentrations in meat compared with concentrate feeding, which can affect meat quality. The FA, antioxidant and secondary metabolite content of plants differ, depending on species, maturity and seasonality, offering the potential through targeted feeding of BDP to produce meat with superior nutritional and antioxidant profiles. This review explores the effect, if any, that grazing ruminants on BDP has on the FA profile, fat-soluble vitamin, and antioxidant content of meat. The input-output relationship between forage and red meat constituents is complex and is likely affected by species diversity, forage consumption patterns and modulation of rumen fermentation processes. Further investigation is required to fully understand the effect that BDP may have on the composition and quality of ruminant meat.

Dairy cow and calf behavior and productivity when maintained together on a pasture-based system

OBJECTIVE

We determined the impact of maintaining pasture-based dairy cows and calves together over 100 days on cow milk production, cow and calf behavior, and calf liveweight and carcass quality.

METHODS

Six Holstein-Friesian cows and their male calves were monitored for 106±8.6 days. Cows were temporarily separated twice a day for milking with calves remaining in the paddock. Cow and calf behaviors were recorded via scan sampling at 6 different timepoints, for the first 7 days and twice a week thereafter. Calves were weighed weekly and immediately processed for meat quality and rumen development analysis at 106±8.6 days. Daily cow milk yields were collected from enrollment until 109±8.6 days (3 days post-weaning).

RESULTS

The average daily gain of calves was 1.4±0.73 kg/d, with an average carcass dressing percentage of 59%. Calves had the greatest frequency of observed close proximity to cow and suckling in the first two weeks and decreased with experiment duration. During separation for milking, cow vocalizations and attempts to return to their calf decreased over time. Reticulorumen weight was on target for calf age, but as a proportion of total stomach weight was lower than industry averages of calves the same age due to the larger abomasum. Cows produced an average of 12±7.6 kg of milk yield per day over the 3-days before the calves were weaned and increased to mean of 31±8.3 kg/d the 3 days after weaning, indicating a consumption of close to 20 kg per calf per day.

CONCLUSION

The impact of a pasture-based cow-calf rearing system on cow and calf behavior and the potential for high levels of calf liveweight gain when provided ad-libitum milk and feed were determined. Further research is required to determine the practicality of replicating such systems with large herds and impact on reared calves post-weaning.

Does the Rearing Management following by Charolais Cull Cows Influence the Qualities of Carcass and Beef Meat?

This study characterized, for the first time, the rearing managements (from birth to slaughter) applied throughout the cull cows’ life and observed the effect of these managements on the carcass and meat properties. From the individual data of 371 Charolais cull cows, three rearing managements were defined and characterized with 60 rearing factors. The results showed that the rearing managements had low effects on the carcass and meat properties. For the carcass traits, only the carcass weight, and fat and longissimus (LM) colors at the level of the sixth rib were impacted. Concerning the meat, only the red color intensity, the fat aroma, the flavor intensity and persistence were affected. According to our results, this study confirmed that it is possible to produce carcass or meat with similar properties; consequently, it is difficult to favor a rearing management. However, to manage jointly both carcass and meat qualities, trade-offs are needed.

Effects of Rearing Management Applied throughout the Charolais Young Bulls' Life on Carcass and Meat Quality

The aim of this work was to study, for the first time, the effects of the rearing management (from birth to slaughter) applied throughout the life of young bulls on carcass and meat quality. Five rearing managements were defined statistically, from a combination of 30 rearing factors, using a hierarchical clustering on principal components. This study considered the individual data of 179 Charolais young bulls from commercial farms. The carcass traits were more sensitive to rearing management than the meat traits. Rearing management had an effect mainly on fat and overall meat grain for the carcass, and on color and tenderness for the longissimus meat. However, it was possible to produce carcass and/or meat with similar properties from different rearing managements. Among the five rearing managements defined in this study, two were identified as allowing the best trade-off to produce simultaneously high carcass and meat quality. The first management was characterized by absence of growth period and a short fattening duration, with a wrapped haylage or corn silage-based diet. The second management was characterized by short pre-weaning and growth periods, and a long fattening period.

Evaluating the Shelf Life and Sensory Properties of Beef Steaks from Cattle Raised on Different Grass Feeding Systems in the Western United States

Consumer interest in grass-fed beef has been steadily rising due to consumer perception of its potential benefits. This interest has led to a growing demand for niche market beef, particularly in the western United States. Therefore, the objective of this study was to assess the impact of feeding systems on the change in microbial counts, color, and lipid oxidation of steaks during retail display, and on their sensory attributes. The systems included: conventional grain-fed (CON), 20 months-grass-fed (20GF), 25-months-grass-fed (25GF) and 20-months-grass-fed + 45-day-grain-fed (45GR). The results indicate that steaks in the 20GF group displayed a darker lean and fat color, and a lower oxidation state than those in the 25GF group. However, the feeding system did not have an impact on pH or objective tenderness of beef steaks. In addition, consumers and trained panelist did not detect a difference in taste or flavor between the 20GF or 25GF steaks but expressed a preference for the CON and 45GR steaks, indicating that an increased grazing period may improve the color and oxidative stability of beef, while a short supplementation with grain may improve eating quality.

Attention to the Details: How Variations in U.S. Grass-Fed Cattle-Feed Supplementation and Finishing Date Influence Human Health

As the global population increases, so does meat consumption. This trend is accompanied by concerns regarding the meat industry, and consumers are demanding transparency on the environmental and health effects of the products they are purchasing. Many leading health organizations recommend reducing red meat consumption. Nevertheless, no differentiation is made among red meats and beef. The beef production system is generally ignored despite nutritional differences between grain- and grass-fed beef. Compared to grain-fed beef, grass-fed beef contains a healthier fatty acid profile, including more omega-3 polyunsaturated fatty acids and conjugated linoleic acid, and increased concentrations of phytochemicals desired by health-conscious customers. However, there is a lack of consistency among grass-fed beef in the United States regarding clear product labeling and cattle dietary components. Grass-fed beef labeling confusion has emerged, including misunderstandings between grass-fed and grass-finished beef. Along with this, previous studies observed significant nutritional variation among grass-finished beef from different producers across the country. Cattle diet has the strongest influence on the nutritional composition of beef. Therefore, understanding differences in feeding practices is key to understanding differing nutritional quality of grass-fed beef. Feeding cattle diverse pastures composed of multiple plant species including grasses and legumes managed in a rotational grazing fashion results in higher omega-3 polyunsaturated fatty acids and phytochemical levels in beef compared to feedlots and monocultures. Seasonal differences including changes in temperature, rainfall, grazing practices, and plant growth cycles affect the nutritional composition of feeds and ultimately meat. Additional feeds utilized in grass-fed beef production systems such as conserved forages may reduce or increase health-promoting nutrients in grass-fed beef, while supplements such as grape byproducts and flaxseed may improve its nutritional profile. Further research should measure the effects of individual feedstuff and the finishing period on the nutritional profile on grass-fed beef. A better understanding of these details will be a step toward the standardization of pasture-raised ruminant products, strengthening the relationship between grass-fed beef consumption and human health.

Growth and Carcass Characteristics of Beef-Cross-Dairy-Breed Heifers and Steers Born to Different Dam Breeds

Simple Summary

The dairy industry is an important source of animals for the beef industry in New Zealand. Since 1998, the proportion of Friesian–Jersey cows in dairy herds has increased from 19% to 49%. The aim of this study was to investigate the effect of dam breed on growth and carcass characteristics of beef-cross-dairy-breed progeny born to Friesian, Friesian-cross, Friesian–Jersey and Jersey-cross cows. Dam breed had an effect on all growth traits, as well as carcass weight, fat colour, fat depth, and ossification score. An increase in Jersey genetics in calves retained for beef finishing would result in calves that take a longer time to reach weaning weight and have a lighter carcass and yellower fat.

Abstract

Approximately two thirds of the annual beef kill in New Zealand originates from the dairy industry. The recent increase in Jersey genetics in the dairy herd will inevitably result in an increase in Jersey genetics entering the beef herd from retention of dairy-origin calves for finishing. Limited literature is available on the effect of dam breed on the performance of beef-cross-dairy-breed progeny. The aim of this study was to investigate the effect of dam breed from dams with varying proportions of Friesian and Jersey genetics on growth traits and carcass characteristics of their 24-month-old beef-cross-dairy-breed heifer and steer progeny. Liveweights of 142 heifers and 203 steers from Friesian (F), Friesian-cross (FX), Friesian–Jersey (FJ) and Jersey-cross (JX) dams were recorded at birth, weaning, as yearlings and at slaughter. Carcass characteristics were also recorded. At each point measured, liveweight was greatest for calves born to F dams. Calves born to F dams took 93 days to reach a weaning weight of 100 kg, whereas those from FX, FJ and JX dams took 99, 101 and 102 days, respectively. Carcass weight was greatest for progeny of F dams (286 kg, compared with 279, 275 and 276 for progeny of FX, FJ and JX dams, respectively). The progeny of JX dams had yellower fat than all other dam breed groups and a greater incidence of excessively yellow fat (fat score ≥ 5).

Effect of Aging and Retail Display Conditions on the Color and Oxidant/Antioxidant Status of Beef from Steers Finished with DG-Supplemented Diets

The aim of this work was to study the effect of finishing diets including distiller grains (DG) on color and oxidative stability of beef after being exposed to aerobic retail display conditions, with or without previous aging. For this purpose, beef samples from animals fed with finishing diets including 0%, 15%, 30%, and 45% DG (on a dry matter basis), which had been exposed to aerobic retail display conditions, with or without previous aging under vacuum packaging, were evaluated. The content of γ-tocopherol, β-carotene, and lutein in diet samples increased with the level of DG. Beef evaluated at 72 h post-mortem showed greater content of γ-tocopherol and retinol as the DG level increased. Meat color was not affected by DG inclusion, but color parameters decreased with retail conditions. Meat from animals fed with DG showed the lowest values of thiobarbituric acid reactive substances (TBARS), independently of the retail display conditions. However, all samples were below the threshold associated with rancid aromas and above the a* value related to meat color acceptance. Thus, feeding diets including up to 45% of DG improved the antioxidant status of meat, preserving the color, and delaying lipid oxidation in meat samples under the display conditions evaluated.

Review: On-farm and processing factors affecting bovine carcass and meat quality

This paper reviews the current state of knowledge on beef carcass and meat quality, with particular emphasis on on-farm and processing factors associated with its high and inconsistent variability. The diversity of livestock systems comes from the diversity of breeds (dairy or beef), ages and gender (bulls, steers, heifers, cull cows) used to produce either mainly beef or beef and milk. In addition, there are factors linked to farming practices (including diet, especially grazing) which significantly influence the sensory, nutritional, technological and extrinsic (such as image) quality attributes of meat. These can become factors of positive differentiation when controlled by the application and certification of technical specifications. Finally, preslaughter (such as stress), slaughter (such as the chilling and hanging method of carcasses) and postslaughter (such as ageing, packaging and cooking) conditions have a strong influence on the microbiological, sensory, technological and image quality attributes of beef. In this review, potential synergisms or antagonisms between the different quality attributes are highlighted. For example, finishing cattle on grass, compared to indoor fattening on a high concentrate diet, has the advantage of producing leaner meat with a higher proportion of omega-3 fatty acids while exhibiting superior oxidative stability, but with the consequence of a darker meat colour and lower productivity, as well as higher seasonality and land surface requirements. Moreover, the control of on-farm factors is often guided by productivity (growth rate, feed conversion ratio) and carcass quality attributes (weight, conformation and fatness). Genetic selection has often been oriented in this direction, without taking other quality attributes into account. Finally, the interactions between all these factors (and especially between on-farm and slaughter or processing factors) are not considered in the quality grading schemes in European countries. This means that positive efforts at farm level may be mitigated or even eliminated by poor slaughtering or processing conditions. All these considerations explain why between-animal variability in quality can be high, even when animals come from the same farming system. The ability to predict the sensory and nutritional properties of meat according to production factors has become a major objective of the supply chain.

The colour and sensory characteristics of longissimus muscle from beef cattle that grazed grass or consumed concentrates prior to slaughter

BACKGROUND

Grazed grass is an important component of the majority of beef production systems used in temperate climates. Compared to concentrate-fed beef, 'grass-fed' beef can command a premium in some markets based on perceived differences in appearance and sensory characteristics. The influence of grazed grass per se, as well as the duration of grazing, on selected sensory characteristics of beef within a heifer production system was examined.

RESULTS

In general, fat from grass-fed cattle was more yellow than fat from similar cattle fed concentrates, whereas muscle from grass-fed cattle was darker than muscle from cattle fed concentrates. At the same carcass weight, muscle from grass-fed cattle had a lower fat concentration than cattle fed concentrates. In the most extreme situation examined, whereby early-maturing heifers were fed concentrates ad libitum from weaning or grazed grass/conserved grass throughout life, until slaughtered at a similar carcass weight (260 kg) and differed in age by 5 months, beef was rated similarly for tenderness and a range of flavours by a trained sensory panel.

CONCLUSION

Within the range of beef heifer production systems examined, the sensory characteristics of grass-fed beef do not differ greatly from concentrate-fed beef. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Retinol and α-Tocopherol Contents, Fat Color, and Lipid Oxidation as Traceability Tools of the Feeding System in Suckling Payoya Kids

The effects of Payoya kid feeding systems on the fat-soluble vitamin (retinol/α-tocopherol) contents, fat content, fat color, and the oxidation index were evaluated to determine their potential for use as feeding system traceability tools. Four groups of Payoya kids (55 animals in total) fed milk exclusively were studied: a group fed a milk replacer (MR) and three groups fed natural milk from dams reared with different management systems (mountain grazing (MG), cultivated meadow (CM) and total mixed ration (TMR)). Kids were slaughtered around one month of age and 8 kg of live weight. Kids from the MG and CM groups presented lower retinol (5.56 and 3.72 µg/mL) and higher α-tocopherol plasma (11.43 and 8.85 µg/mL) concentrations than those from the TMR and MR groups (14.98 and 22.47 µg/mL of retinol; 2.49 and 0.52 µg/mL of α-tocopherol, respectively) (p < 0.001). With respect to fat, kids with a higher intramuscular fat percentage (CM and TMR groups) had lower retinol contents (16.52 and 15.99 µg/mL, respectively) than kids from the MG and MR groups (26.81 and 22.63 µg/mL, respectively) (p < 0.001). A dilution effect of vitamins on fat was shown: the higher the amount of fat, the lower the vitamin concentrations, the higher the lipid oxidation index (MDA), and the lower the SUM (absolute value of the integral of the translated spectra between 450 and 510 nm). A discriminant analysis that included all studied variables showed that 94.4% of the kids were classified correctly according to their feeding system and could allow traceability to the consumer.

Effect of feeding Sesbania sesban and reed grass on growth performance, blood parameters, and meat quality of growing lambs

This study was conducted to evaluate the effects of green fodders, fresh Sesbania sesban, and reed grass, on growth performance, blood metabolites, and meat quality of growing lambs. Twenty-one male Farafra lambs (19.0 ± 1.87 kg body weight) were randomly distributed into three groups, each with seven animals. The first group was fed on 60% concentrates and 40% fresh alfalfa, and served as a control. The second and third groups were fed also on 60% concentrates plus 40% fresh Sesbania sesban and reed grass, respectively. Lambs were fed the diets until reaching the target slaughter weight of about 50.0 kg, which was obtained after a period of 215 days. Five lambs from each group were randomly selected and slaughtered at the end of the experiment. Slaughter body weight, carcass traits weight, and dressing percentage were estimated. Chemical composition and physical properties of longissimus dorsi muscle, from the animals' right side, were determined. It was found that no significant (P > 0.05) differences among groups in body weight, average daily gain, feed conversion rate, hot carcass, dressing percentage, and carcass components were observed. The forage intake of Sesbania and alfalfa tended to be higher than that of reed forage. There were no significant (P > 0.05) differences in the blood parameters among the treatments, except the urea level which was higher in Sesbania sesban group than the reed one. However, the serum urea concentration in Sesbania and reed groups was similar to that of alfalfa. Sesbania sesban and reed forages decreased (P < 0.05) the eye muscle area and shear force in lambs when compared to the control group. The longissimus dorsi muscle of the Sesbania and reed treatments was found to be numerically higher in the moisture and lower in the fat and collagen contents than the alfalfa group. Most of meat and fat color parameters were improved by feeding of Sesbania and reed forages. In conclusion, Sesbania sesban or reed grass, as unconventional forage sources, can be used as alternatives of the commonly used alfalfa feed. Moreover, these sources could enhance the meat quality of lambs and increasing the tenderness with accepted meat and fat color. So, it can be recommended to use Sesbania or reed grass forages in diets of sheep, to overcome the rising in the price or shortage in the availability of traditional green fodders.

How Management System Affects the Concentration of Retinol and α-Tocopherol in Plasma and Milk of Payoya Lactating Goats: Possible Use as Traceability Biomarkers

Simple Summary

The milk production systems in goats are mainly intensive and semi-extensive. In the former, the goats are housed and are fed a total mixed ration with vitamin supplementation. In the latter, the feeding of the goats is based on grazing, although with some supplementation with compound feed. Retinol and α-tocopherol that appear in these animals come from the feeding regime, since the animal cannot synthesize them. The objective of this study was to verify if the vitamins provided in different management systems of Payoya lactating goats are good markers of the production system. For this purpose, the content of carotenoids, retinol and α-tocopherol in the milk and plasma of the goats was quantified. Results showed an inverse relationship of the amount of these vitamins between milk and plasma. On the other hand, the metabolism of different vitamins depends on their origin (natural/synthetic), with natural α-tocopherol and synthetic retinol showing the highest amount in milk. Finally, it was found that these compounds can be good traceability tools which allows to guaranty to the consumer the origin of the products derived from these animals.

Abstract

The retinol and α-tocopherol concentrations were quantified (μg/mL) using high-performance liquid chromatography (HPLC) in both plasma and milk of goats from three management systems. The aim was to investigate if the compounds pass from feed to animals’ fluids and to evaluate their potential use as feeding regime biomarkers. A total of 45 Payoya dams were distributed in three groups according to management system during the first month of lactation: mountain grazing (MG), cultivated meadow (CM) and total mixed ration (TMR). TMR group had higher concentrations of retinol in both plasma (25.92 ± 3.61 at 30 days postpartum) and milk (8.26 ± 0.79 at 10 days postpartum), and they were also the unique animals whose milk contained detectable concentrations of α-tocopherol (3.15 ± 0.19 at parturition). However, MG and CM goats showed higher plasma concentrations of α-tocopherol (64.26 ± 14.56 and 44.65 ± 5.75 at 30 days postpartum, respectively). These results could imply differences in the bioavailability of supplemented vitamin A and natural β-carotene and between the natural/synthetic forms of α-tocopherol. An inverse relationship between the fluids (plasma/milk) in the contents of α-tocopherol and retinol was observed as lactation progressed. Since 80% of the animals were correctly classified using a discriminant analysis based on these vitamins, these compounds could be used as traceability biomarkers of feeding system, but further studies are necessary to know the possible passage to kid meat.

Effect of Dietary Bacillus coagulans and Different Forms of Zinc on Performance, Intestinal Microbiota, Carcass and Meat Quality of Broiler Chickens

A total of 288-day-old male broilers were allocated to six dietary treatments to evaluate the effects of zinc source and Bacillus coagulans supplements and their interaction on growth, intestinal microbial population, carcass traits and meat quality in broiler chickens. Three levels of dietary supplemental Zn source (100 mg/kg of DM diet zinc oxide, 25 and 50 mg/kg of diet zinc oxide nanoparticles (Zn-nan)) and two levels of B. coagulans (0 and 100 mg/kg of diet) were combined as a completely randomised design with a 3 × 2 factorial arrangement. B. coagulans increased the body weight gain, body weight and feed conversion ratio. The lactic acid producing bactereia of ileal were increased by B. coagulans supplementation, and its coliform count was decreased by Zn-nan in a dose-dependent manner. The B. coagulans increased the relative weights of legs and proventriculus and reduced weights of livers, abdominal fat and meat thiobarbituric acid (TBA) value. Likewise, dietary B. coagulans increased pH, yellowness and lightness values of leg muscles. Birds fed Zn-nan50 had lower liver weight, TBA and cooking loss and higher yellowness values than chicks fed ZnO-100. In conclusion, the dietary supplementation with B. coagulans improved broiler performance, microbial population and meat quality. The Zn-nan in lower dose could be a good substitution in mineral premix instead of zinc oxide. In addition, the Zn-nan improved intestinal microbial population, carcass characteristics and oxidative stability of chicken meat; however, the combination of two levels of Zn-nan with B. coagulans did not vary the measured parameters.

Growth performance, carcass traits and meat quality of lambs fed increasing level of Macadamia nut cake

A total of 40 lambs were divided into four different treatments according to the inclusion level of the macadamia nut cake: C-control (0%), M1 (6.5%), M2 (12%) and M3 (20%). Feed was provided twice a day; animal weighing along with body condition scoring occurred within a 14-day interval. The lambs were slaughtered at the end of the performance test. Analysis of variance was performed through the Mixed procedure of the SAS, as well as linear and quadratic regression analysis. The groups presented differences between the treatments (P <0.05) for dry matter intake (DMI), ethereal extract intake (EEI), consumption in relation to live weight percentage and feed conversion ratio (FCR). The lowest mean DMI was obtained by the animals that received the M2 and differed from the C treatment, whose average was the highest. The EEI was highest for the M3 group and the FCR was also better for this group. There was a linear effect for EEI and FCR, and quadratic for crude protein intake. There was no effect for carcass characteristics, and only initial pH had a decreasing linear effect. The macadamia nut cake was effective in promoting the performance of the animals, since there was an improvement in feed conversion.

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.

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.

Metabolic Regulations by lncRNA, miRNA, and ceRNA Under Grass-Fed and Grain-Fed Regimens in Angus Beef Cattle

Beef cattle raised under grass-fed and grain-fed have many differences, including metabolic efficiency and meat quality. To investigate these two regimens' intrinsic influence on beef cattle, we used high-throughput sequencing and metabolomics analyses to explore differentially expressed genes (DEGs) and metabolimic networks in the liver. A total of 200 DEGs, 76 differentially expressed miRNAs (DEmiRNAs), and two differentially expressed lncRNAs (DElncRNAs) were detected between regimen groups. Metabolic processes and pathways enriched functional genes including target genes of miRNAs and lncRNAs. We found that many genes were involved in energy, retinol and cholesterol metabolism, and bile acid synthesis. Combined with metabolites such as low glucose concentration, high cholesterol concentration, and increased primary bile acid concentration, these genes were mainly responsible for lowering intramuscular fat, low cholesterol, and yellow meat in grass-fed cattle. Additionally, we identified two lncRNAs and eight DEGs as potential competing endogenous RNAs (ceRNAs) to bind miRNAs by the interaction network analysis. These results revealed that the effects of two feeding regimens on beef cattle were mainly induced by gene expression changes in metabolic pathways mediated via lncRNAs, miRNAs, and ceRNAs, and contents of metabolites in the liver. It may provide a clue on feeding regimens inducing the metabolic regulations.

Sire Effects on Carcass of Beef-Cross-Dairy Cattle: A Case Study in New Zealand

Simple Summary

Cattle born in the dairy industry are a very important source of beef. This study evaluated the carcasses of cattle born to dairy cows and sired by a range of Angus and Hereford sires. Sire affected most carcass traits of their progeny, particularly size and fat traits. The heaviest sire had 46 kg greater carcass weight compared with the lightest sire, equivalent to NZ$266 greater value per progeny. Carcass fat traits (rib fat depth and marble scores) were the most variable among sires, indicating possibility of selection. Thus, using beef-breed sires chosen for greater carcass weight has the potential to increase the meat production of cattle born on dairy farms, while maintaining adequate fat levels and carcass quality to receive optimum payment.

Abstract

There is interest in increasing the carcass value of surplus calves born in the dairy industry that are reared for beef production in New Zealand. This experiment evaluated the carcass of Angus and Hereford sires via progeny testing of beef-cross-dairy offspring grown on hill country pasture. Weight and carcass traits were analyzed from 1015 animals and 1000 carcasses of 73 sires. The mean of the progeny group means was 567 kg for live weight at slaughter, 277 kg for carcass weight, 48.9% for dressing-out, 240.3 cm for carcass length, 73.6 cm² for eye muscle area, 7.4 mm for rib fat depth, 0.91 for marble score, 3.05 for fat color score, 3.01 for meat color score, and 5.62 for ultimate pH. Sire affected (p < 0.05) carcass size and fat traits, but not fat color, meat color, or ultimate pH (p > 0.05). There was a 46 kg increase in carcass weight between the best and worst sires tested. Carcass fat traits were the most variable among sires. The use of genetically superior beef-breed sires over dairy-breed cows has the potential to increase carcass weights from surplus calves born in the dairy industry, while maintaining adequate fat levels and carcass quality.

Health-Promoting Phytonutrients Are Higher in Grass-Fed Meat and Milk

While commission reports and nutritional guidelines raise concerns about the effects of consuming red meat on human health, the impacts of how livestock are raised and finished on consumer health are generally ignored. Meat and milk, irrespective of rearing practices, provide many essential nutrients including bioavailable protein, zinc, iron, selenium, calcium, and/or B12. Emerging data indicate that when livestock are eating a diverse array of plants on pasture, additional health-promoting phytonutrients—terpenoids, phenols, carotenoids, and anti-oxidants—become concentrated in their meat and milk. Several phytochemicals found in grass-fed meat and milk are in quantities comparable to those found in plant foods known to have anti-inflammatory, anti-carcinogenic, and cardioprotective effects. As meat and milk are often not considered as sources of phytochemicals, their presence has remained largely underappreciated in discussions of nutritional differences between feedlot-fed (grain-fed) and pasture-finished (grass-fed) meat and dairy, which have predominantly centered around the ω-3 fatty acids and conjugated linoleic acid. Grazing livestock on plant-species diverse pastures concentrates a wider variety and higher amounts of phytochemicals in meat and milk compared to grazing monoculture pastures, while phytochemicals are further reduced or absent in meat and milk of grain-fed animals. The co-evolution of plants and herbivores has led to plants/crops being more productive when grazed in accordance with agroecological principles. The increased phytochemical richness of productive vegetation has potential to improve the health of animals and upscale these nutrients to also benefit human health. Several studies have found increased anti-oxidant activity in meat and milk of grass-fed vs. grain-fed animals. Only a handful of studies have investigated the effects of grass-fed meat and dairy consumption on human health and show potential for anti-inflammatory effects and improved lipoprotein profiles. However, current knowledge does not allow for direct linking of livestock production practices to human health. Future research should systematically assess linkages between the phytochemical richness of livestock diets, the nutrient density of animal foods, and subsequent effects on human metabolic health. This is important given current societal concerns about red meat consumption and human health. Addressing this research gap will require greater collaborative efforts from the fields of agriculture and medicine.

Feeding unsaleable carrots to lambs increased performance and carcass characteristics while maintaining meat quality

This study investigated the effect of feeding unsaleable carrots to lambs within a total-mixed ration (TMR) on performance, carcass characteristics, meat quality and sensory parameters. Thirty-six Australian Merino wether lambs were fed a control (barley-based) or carrot-based TMR for 11-weeks. Carrot-fed lambs had 2.7% higher cold dressing percentage (P = 0.03) while consuming less than control lambs. Subcutaneous fat of carrot-fed lambs contained less branch-chained, and more cis- and trans-monounsaturated fatty acids (FA; P ≤ 0.01) compared to control-fed lambs, which tended (P = 0.08) to have higher concentrations of polyunsaturated FA, despite the Longissimus lumborum (LL) muscle being unchanged by diet. Under retail display conditions, L* and hue values were lower (P ≤ 0.04) for 5 d aged LL samples from carrot-fed lambs. No differences were observed in other meat quality and sensory parameters between diets. Therefore, feeding unsaleable carrots at 45% DM in a TMR can improve lamb performance and carcass characteristics, while maintaining meat quality and FA composition.

Grain supplementation of calves as an alternative beef production system to pasture-finished steers in Chilean Patagonia: meat quality and fatty acid composition

Beef production in Chilean Patagonia is based on steer finishing on pastures with low nutritive value. Grain supplementation for finishing calves on pasture arises as an attractive alternative to shorten the finishing phase and improve the production efficiency of the traditional system. The aim of this study was to compare meat quality and fatty acid (FA) composition of beef from steers and calves. Forty Angus cross steers were raised on pasture and slaughtered at 18 to 20 mo of age (448 ± 31.7 kg body weight). An additional group of 10 calves from similar genetics was weaned at 9 mo of age (303 ± 8.0 kg) and subsequently supplemented with 2.5 kg corn plus 1.0 kg commercial concentrate daily while on pasture during 47 d, until they reached slaughter weight (316 ± 13.9 kg). All animals were slaughtered on the same day and the Longissimus thoracis muscle was removed from each carcass for meat quality and FA profile analysis. Hot carcass weight from calves was lighter than steers (174 ± 7.9 vs. 224 ± 17.5 kg, P ≤ 0.001). Meat from calves was lighter (higher L*) and less red (lower a*). In addition, meat from calves showed lower level of yellow pigments in subcutaneous fat (lower b*) compared with meat from steers (P ≤ 0.001). Meat from calves was more tender than meat from steers (P ≤ 0.05), although both shear force values were low and within recommendations for high consumer acceptability. Meat from both production systems showed fat content and FA profiles within dietary recommendations for a healthy diet. However, meat from calves was leaner (1.10 ± 0.29 vs. 2.00 ± 0.72% fat, P ≤ 0.001). Meat from calves showed lower percentages of saturated (P ≤ 0.05) and monounsaturated (P ≤ 0.001) FAs and higher percentages of polyunsaturated and n-3 (P ≤ 0.001) FAs and conjugated linoleic acid (total and 9c,11t-18:2 isomer, P ≤ 0.001) than meat from steers. Grain supplementation of calves on pasture can reduce the finishing period by 8 to 10 mo at the expense of lighter carcasses with similar or improved meat quality characteristics compared with the traditional finishing of steers on pasture. Implementation of the alternative production system will depend mainly on feed costs and target carcass weights for specific markets.

The influence of Megasphaera elsdenii on rumen morphometrics of cull cows immediately stepped up to a high-energy finishing diet

Forty-five beef cull cows [body weight (BW) = 503 ± 58 kg; body condition score (BCS) = 2.1 ± 0.6] were randomized into two treatments to compare the effects of oral drenching of no probiotic vs. 100 mL of Megasphaera elsdenii NCIMB 41125 (M. elsdenii culture; Lactipro Advance; 2 × 10⁸ cfu/mL; MS Biotec, Inc., Wamego, KS) on the realimentation of cull cows. The study featured a rapid 0-d step-up of concentrate-naïve cull cows to a 90% concentrate diet (1.43 Mcal/kg of NE_g). The cows were finished for 35 d and were fitted with a wireless rumination tag (Allflex Flex Tag; SCR Engineers, Ltd, Netanya, Israel), which tracked head movement to record eating and chewing activity. Rumen morphometrics was recorded on the harvest floor, with each carcass assigned a rumenitis score, and a fragment of the cranial sac removed for further papillae analysis. An additional 23, thin, non-fed cull cows were harvested at the same abattoir to compare the effects of concentrate realimentation on ruminal morphometrics. Megasphaera elsdenii culture-drenched cattle registered a 13.3% increase in rumination time (39.27 min/d, P = 0.03) during the first week of the trial compared to controls. A numerical rumination advantage for M. elsdenii culture-administered cattle was observed during week 2 of trial (P = 0.17), with no differences between treatments from weeks 3 to 5 (P ≥ 0.40). Subjective rumenitis evaluations approached a tendency (P = 0.12), with non-M. elsdenii culture-drenched concentrate-fed cattle logging twice the score of their day 0 cohorts (2.52 vs. 1.17) suggesting considerable lactic insults occurred to the ruminal epithelium in the short 35-d trial. Despite the short feeding duration, concentrate realimentation prompted a significant improvement in mean papillae area (P < 0.01). Among concentrate-fed treatments, M. elsdenii culture-drenched cattle posted superior absorptive surface area (P = 0.01) and a greater ratio of papillae area of absorptive surface area (P = 0.05), suggesting that M. elsdenii culture is favorably altering the ecology of the rumen and promoting papillae growth perhaps by mitigating lactate-driven pH drops. In conclusion, M. elsdenii culture application in a 0-d step-up protocol to finishing diets can help mitigate the effects of ruminal acidosis.

Preliminary investigation into the use of Raman spectroscopy for the verification of Australian grass and grain fed beef

Australian grass and grain-fed beef products attract premium prices at sale and several beef processors market beef underwritten by production system claims. This preliminary investigation assessed the feasibility of using Raman spectroscopy to detect differences in the chemical composition of subcutaneous fat from cattle raised in extensive and intensive production systems. Raman spectra, fatty acid composition, β-carotene composition and objective colour measurements were measured on 150 grass and 150 grain-fed cattle. Spectral differences at peaks including 1069 cm^-1, 1127 cm^-1, 1301 cm^-1 and 1445 cm^-1 suggest that Raman spectra is able to detect differences in saturated fatty acids, which were significantly higher in carcases from grain-fed cattle. Differences in spectra at 1658 cm^-1 were observed, however further research is required to investigate the cause of this spectral feature. Overall, this study indicated that Raman spectroscopy is a potential tool for the authentication of beef carcases from grass and grain-fed production systems.

Pumpkin Waste as Livestock Feed: Impact on Nutrition and Animal Health and on Quality of Meat, Milk, and Egg

Simple Summary

Pumpkin waste are part of the millions of tons of vegetable residues produced yearly that could be used in livestock feeding. Their value not only relies in its nutritional content as its bioactive compounds could modify meat, milk, and egg composition which are of uttermost value for human nutrition. Furthermore, pumpkin waste, which cannot be used in human consumption, may contribute to diminish human-livestock competition for cropland. In this review, we describe the potential of pumpkin waste as animal feedstock as a strategy for more sustainable livestock production while making emphasis on the importance of food from animal origin in human health.

Abstract

Meat, milk, and egg contribute positively to the nutrition and health of humans; however, livestock requires a large number of resources, including land for fodder and grains. Worldwide millions of tons of vegetable waste are produced without any further processing, causing pollution and health risks. Properly managed vegetable waste could provide a source of feed for livestock, thus reducing feeding costs. In this regard, pumpkin waste (Cucurbita sp.) is an alternative. Research on pumpkin waste on animal nutrition is scarce, however, it has potential as animal feed not only for its nutritional value but also for its antioxidants, pigments, and polysaccharides content that could enhance quality of meat, milk, and egg, as well animal health. In this review, we describe the environmental impact of livestock as a result of greater demand for food of animal origin, including the importance of the consumption of animal foods in human nutrition and health. Moreover, we emphasize the potential of plant residues and, particularly, on the characteristics of pumpkins and how their use as feedstuff for livestock could improve productivity and modify the composition of meat, milk, and egg.

The color of skin: yellow diseases of the skin, nails, and mucosa

The colors reflected from the skin are important indicators of dermatologic and systemic disorders. Incident light is subject to absorption by chromophores in the skin and scattering. Chromophores associated with yellow light reflection include the carotenoids and bilirubin. Various pathophysiologic mechanisms associated with these and other chromophores manifest with a yellow hue on examination. This review describes these mechanisms and the clinical features of yellow skin disorders by morphology. A brief summary of the differential diagnosis, laboratory investigations, and treatments are presented. Yellow skin disorders are a heterogenous group composed of abnormalities in keratin, elastic and connective tissue, lipid metabolism, and other states of metabolic, inflammatory, or organ dysfunction. Patients will present through different routes, and skin disease may precede or follow systemic disease. Dermatologists have an essential role in identifying those with malignant or systemic associations to ensure early diagnosis and treatment.

Postweaning Exposure to High Concentrates versus Forages Alters Marbling Deposition and Lipid Metabolism in Steers

Angus-cross steers (n = 20; 261 ± 21.5 kg BW) were used to examine how early exposure to high concentrates or high quality forages altered marbling deposition and lipid metabolism. Steers were randomly assigned to high concentrate diet (CONC) or high quality forages (FOR) at 30-d postweaning, fed for 127 d, and slaughtered. Data were analyzed using a mixed model that included fixed effect(s) of dietary treatment (CONC vs. FOR), time (for plasma levels, ultrasound measures, and postmortem aging time) and two-way interaction (when appropriate). Steers fed CONC had greater (P < 0.01) ADG and heavier (P < 0.001) body weight at 127 d. Ultrasound measures over time showed greater (P < 0.001) intramuscular fat deposition at d 98 and 126 for CONC than FOR steers. Steers fed CONC had elevated (P < 0.05) plasma glucose and insulin concentrations from d 57 to 127 compared to FOR. Early exposure to CONC increased (P < 0.01) dressing percent, HCW, LM area, 12th rib fat thickness, and marbling scores compared to FOR. Total lipid content of the LM was greater (P < 0.01) for CONC than FOR; however, moisture, protein, and ash content was lower (P < 0.01) for CONC than FOR. Concentrate fed steers had greater (P < 0.01) MUFA content and lower (P < 0.01) polyunsaturated fatty acids PUFA n-3 content than FOR. The n-6:n-3 ratio was greater (P < 0.01) for CONC due to decreased (P < 0.01) in n-3 fatty acid content with CONC. Gene expression was up-regulated (P < 0.05) for key lipogenic genes and downregulated for glucose transporter 4 in steers fed CONC vs. FOR. Early exposure to CONC diets for 127 d at 30 d postweaning stimulated marbling deposition and resulted in these carcasses grading 80% Choice when slaughtered at 13 mo of age and 248 kg HCW.

Effect of Linseed Supplementation on Total Longissimus Muscle Lipid Composition and Shelf-Life of Beef From Young Maremmana Bulls

Twenty young Maremmana bulls were randomly allotted to two dietary groups during a finishing period (~90 days): C diet (without lipid supplementation), and L diet (with linseed supplementation, 20% concentrate feed). The aim was to investigate the effects of dietary linseed supplementation on the intramuscular fat composition, and the shelf-life of minced beef. The L diet did not alter the dressing rate and daily weight gain, whereas the C18:3n-3 content in the intramuscular fat significantly increased (from 0.85 to 1.78 g/100 g of total fatty acid, +109%), leading to a reduction in a n-6/n-3 ratio below four and an increase in the overall proportion of long chain n-3 fatty acids in beef lipids. These effects were principally related to differences in the distribution of fatty acids between the neutral and polar lipids. The results demonstrated that linseed supplementation modified the lipid composition of beef, without negatively impacting overall productivity, in the period from weaning the bull until its slaughter. However, the total amount of n-3 fatty acids in the beef of young bulls on the L diet, was not sufficient for the aliquot of humans' n-3 fatty acid requirements. This was mainly related to the low levels of fat in the beef. Comparing beef samples from animals on the L diet, with samples from animals on the C diet, the higher levels of n-3 polyunsaturated fatty acids led to a significant reduction of shelf-life starting after 2 days of storage at 4°C, because of fatty acid and cholesterol oxidation. The L diet group samples showed a higher level of TBARS (+80%) and COPs (+73%), two important parameters to estimate the oxidation level of beef. This suggests that enriching beef with n-3 fatty acids should be coupled with packaging techniques that consider the higher susceptibility to lipid oxidation. In conclusion, dietary linseed supplementation led to a higher proportion of n-3 fatty acids in beef lipids, however, the natural content of antioxidant substances was not able to protect intramuscular fat from oxidation during storage at 4°C.

An evaluation of environmental, intrinsic and pre- and post-slaughter risk factors associated to dark-cutting beef in a Federal Inspected Type slaughter plant

The objective was to determine the risk factors associated to dark-cutting in bovine carcasses. The study was conducted at a Federal Inspection abattoir located in northeastern Mexico. A random sample of 394 animals at slaughter was used. A total of 26 explanatory variables were evaluated; the analysis included environmental, animal-specific, and management factors both at pre- and post- slaughter periods. Only four variables were statistically significant within the final logistic regression model (P < .001). The frequency of dark-cutting carcasses was 13.45%. Lairage time was directly proportional to the percentage of risk for dark-cutting beef. Improper desensitization also increased the frequency of carcasses with this anomaly. Backfat thickness and the 24-h pH differential of the carcasses were inversely proportional to the risk for dark-cutting beef. An interesting finding was that risk factors for DFD meat are present in all stages of the slaughter process and thus to effectively address this problem an integral evaluation is needed throughout the slaughter process.

Carcass characteristics and meat quality of Nellore bulls submitted to different nutritional strategies during cow-calf and stocker phase

There have been few studies realized that evaluate the effects of adopting different nutritional systems in more than one phase of cattle production on carcass and meat characteristics. This study was realized to evaluate carcass and meat characteristics from bulls submitted to different nutritional systems during two production phases. The experiment was conducted at Figueira's farm during two production phases: I (cow-calf) - 80 calves (99.6±2.72 days of age and 109.7±2.99 kg of BW) with their mothers were randomly assigned into two supplemental diets: cow-calf mineral supplement (n=40) or cow-calf creep-feeding (n=40); II (stocker) - the same 80 calves (201.2±2.11 days of age and 190.2±3.37 kg of BW) were redistributed into two production systems: stocker pasture (n=40) or stocker feedlot (SF; n=40). After, all 80 animals were kept on a pasture system (III) for 290 days, and then finished in a feedlot system (IV) for more 33 days. Then, they were slaughtered at an average 764.2±3.06 days of age and at 499.2±3.33 kg of final BW. After slaughter, the average daily gain was calculated, and the carcass and meat characteristics were measured. The statistical model design used was completely randomized in a 2×2 factorial arrangement (two treatment groups on cow-calf phase and two treatment groups on stocker phase). The single effects between the groups in each phase and the interactions between both phases (cow-calf v. stocker) were analyzed. The results were compared by Fisher's test, using the R statistical software. A cow-calf by stocker phases interaction occurred for carcass conformation and fiber diameter. For single effects, the greatest influences observed were in the stocker phase. The feedlot group was slaughtered 17 days earlier, with greater final BW (3.8%), hot carcass weight (5.7%), average daily gain (6.9%), dressing percentage (1.8%), carcass length (1.8%), carcass width (1.5%), longissimus muscle area (4.8%) and muscle depth (2.3%) than pasture group. The SF group also had influence on fat color; showing higher L* and lower b* values. These results reveal that bulls reared in feedlot at the stocker phase have higher muscle development and that the stocker phase has the greatest potential to influence carcass characteristics and meat quality.

A comparison of the Nix Colour Sensor Pro™ and HunterLab MiniScan™ colorimetric instruments when assessing aged beef colour stability over 72 h display

We compared the capacity for the Nix Colour Sensor Pro™ (NIX) and HunterLab MiniScan™ (HUNTER) to detect colour variation using aged (0, 3 and 5 weeks) and then displayed (0, 1, 2 and 3 d) beef M. longissimus lumborum samples (n = 8). NIX L* and hue values were found to be respectively higher and lower than for the HUNTER. No significant interactions between instrument and display or ageing periods were identified for a* - unlike for b* and chroma where NIX measures were observed to be lower than those from the HUNTER. Both instruments identified ageing and display period effects on colorimetric traits. Based on these results, the NIX cannot be considered comparable to the HUNTER when measuring beef colour - albeit captured similar colorimetric trends over display and ageing periods which suggest its independent usefulness to beef colour assessment.

Meat provenance: Authentication of geographical origin and dietary background of meat

The authenticity of meat is now an important consideration in the multi-step food chain from production of animals on farm to consumer consumption of the final meat product. A range of techniques, involving analysis of elemental and molecular constituents of meat, fingerprint profiling and multivariate statistical analysis exists and these techniques are evolving in the quest to provide robust methods of establishing the dietary background of animals and the geographical origin of the meat derived from them. The potential application to meat authentication of techniques such as stable isotope ratio analysis applied to different animal tissues, measurement in meat of compounds directly derived from the diet of animals, such as fatty acids and fat soluble vitamins, and spectroscopy is explored. Challenges pertaining to the interpretation of data, as they relate to assignment of dietary background or geographical origin, are discussed.

Effects of feeding legume-grass pasture and different concentrate levels on fatty acid profile, volatile compounds, and off-flavor of the M. longissimus thoracis

Pasture-finished beef is becoming more popular among consumers due to concerns related to fatty acid content and sustainable practices. The effects of finishing crossbred steers on legume-grass pasture comprised of oats, ryegrass, and clover (PAST), legume-grass pasture plus whole corn grain (WCG) supplementation (SUPP), and only with WCG (GRAIN) on fatty acids profile, volatile compounds, sensory, and texture attributes were studied. Pasture diets (PAST and SUPP) led to lower n-6/n-3 ratio (P < 0.001), and highest deposition of C18:2 cis-9 trans-11 (P < 0.001) in the lean. Beef from steers fed GRAIN had the highest values of volatile compounds associated with lipid oxidation. Off-flavor intensity was significantly greater on beef from steers fed GRAIN when compared to PAST. Overall, muscles from steers finished on PAST and SUPP showed similar attributes but differ when compared to GRAIN. The presence of forage is essential to improve fatty acid profile, decrease volatile compounds associated with lipid oxidation, and minimize off-flavor.

Bioactive Compounds in Functional Meat Products

Meat and meat products are a good source of bioactive compounds with positive effect on human health such as vitamins, minerals, peptides or fatty acids. Growing food consumer awareness and intensified global meat producers competition puts pressure on creating new healthier meat products. In order to meet these expectations, producers use supplements with functional properties for animal diet and as direct additives for meat products. In the presented work seven groups of key functional constituents were chosen: (i) fatty acids; (ii) minerals; (iii) vitamins; (iv) plant antioxidants; (v) dietary fibers; (vi) probiotics and (vii) bioactive peptides. Each of them is discussed in term of their impact on human health as well as some quality attributes of the final products.

Genetic divergence in residual feed intake affects growth, feed efficiency, carcass and meat quality characteristics of Angus steers in a large commercial feedlot

Growth, feed intake, feed efficiency, and carcass and meat quality characteristics of 136 Angus steers differing in genetic merit for post-weaning residual feed intake (RFIp) were measured over 251 days in a large commercial feedlot. The steers were evaluated in two groups, low (Low-RFI) and high (High-RFI) genetic RFIp, measured by estimated breeding values for RFIp (RFIp-EBV). The difference in RFIp-EBV between the Low- and High-RFI groups was 1.05 kg/day (–0.44 vs 0.61 kg/day; P < 0.05). The Low- and High-RFI steers were similar (P > 0.05) in age (445 vs 444 days) and weight (435 vs 429 kg) at induction, and at the end of the feeding period (705 vs 691 kg). Average daily gain (ADG) over 251 days had a small negative association with variation in RFIp-EBV (P < 0.05), reflecting a 3.6% greater ADG accompanying a difference of 1 kg/day in RFIp-EBV. Pen feed intake and feed conversion by the Low-RFI group were 10.4 kg/day and 9.3 kg/kg, and for the High-RFI group were 11.1 kg/day and 10.4 kg/kg, but without availability of individual animal feed-intake data it was not possible to test for significant differences. Carcass weight and dressing-percentage was similar for the Low- and High-RFI steers. High-RFI steers had a significantly (P < 0.05) greater depth of subcutaneous rib fat at induction and finished with 5 mm more (P < 0.05) fat at the 10/11th ribs on the carcass than the Low-RFI steers. Cross-sectional area of the eye-muscle and three measures of intramuscular or marbling fat did not differ (P > 0.05) between the Low- and High-RFI steers. Shear force was higher (P < 0.05) in meat samples aged for 1 day from the Low-RFI steers, but there was no difference (P > 0.05) from the High-RFI steers after 7 days of ageing. Compression values for meat samples aged for 1 day did not differ between the RFI groups but were higher in meat samples aged for 7 days from the Low-RFI steers. For these Angus steers, genetic superiority in RFI was associated phenotypically with superior weight gain, decreased rib fat depth, slightly less tender meat, and no compromise in marbling fat or other carcass and meat quality traits.

Effect of the genetic group, production system and sex on the meat quality and sensory traits of beef from crossbred animals

The crossbreeding of two or more breeds from the Bos taurus and Bos indicus species is an alternative for obtaining high-quality meat from animals adapted to tropical climates. Quality and sensory attributes of beef, mainly its tenderness and flavour, are very important with regard to the consumer's point of view. This study aimed to evaluate the physico-chemical and sensory characteristics of crossbred young bulls and heifers, the offspring of Angus or Limousin bulls and 1/2 Angus + 1/2 Nellore or 1/2 Simental + 1/2 Nellore cows that were finished on feedlot or pasture. Meat quality traits (pH, colour, cooking loss, water holding capacity and shear force) and sensory parameters (characteristic beef aroma/flavour intensity, strange aroma/flavour intensity, tenderness and juiciness descriptive attributes, flavour, texture (tenderness) and overall acceptance) were evaluated. The genetic group had an effect on the beef pH, but it was not as relevant as the effect of the combination between the production system and the sex or genetic group, which affected many of the quality and sensory traits.

Impact of ground soybean and starch levels on the quality of meat from feedlot young Nellore bulls

Twenty-eight young Nellore bulls (395±32kg initial body weight) were assigned to a completely randomized design (2×2 factorial design with 7 animals per treatment) to evaluate effects on the quality of meat. Diet treatments consisted of high (about 25%) or low (about 16%) starch levels, with or without ground soybean addition. Shear force was decreased in the meat from animals fed a low-starch diet (P=0.0016). Meat from animals fed a high-starch diet had increased total concentrations of unsaturated (P=0.0029) and monounsaturated fatty acids (P=0.0253). Polyunsaturated fatty acid content increased in the meat from animals fed a diet containing soybean (P=0.0121). High starch diets (>25%) decreased the concentration of saturated fatty acids and increased the amount of unsaturated fatty acids in the meat from young Nellore bulls.