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Although more than 3 million head of dairy cows enter the food supply chain in the U.S. every year, research on this topic remains limited and scarce. Meat production from dairy cows is a significant component of beef production, accounting for almost 10% of U.S. commercial beef production. Thus, the purpose of this review is to demonstrate the importance of dairy cows as a beef source, and to provide an overview on topics from farm to meat product—culling, marketing, transportation, welfare, body composition and its relationship with lactation particularities, carcass characteristics, meat quality, and traceability. Current scientific evidence has shown that culling a dairy cow at an appropriate time has beneficial effects on cow welfare and, consequently, cow value. During marketing the dairy cow is visually evaluated for health and factors associated with its expected carcass value; thus, marketing a well-conditioned cow will ensure that the animal is fit for transportation and provides high carcass yield. However, limitations such as low body condition score, lameness or mobility problems, and visual defects remain persistent. Even though beef harvest plants accommodate cows in all body composition states, the current carcass grade system does not reflect the mature cow industry needs. Therefore, improvement of the grading system could maximize carcass utilization and increase cow carcass value by recognizing subprimal cuts that could be merchandised as whole muscle cuts. Lastly, implementation of a traceability system would unify information from the farm to harvest assisting the industry in making further advancements.

Cull dairy cows contribute almost 10% of national beef production in the United States. However, different factors throughout the life of dairy cows affect their weight and overall body condition as well as carcass traits, and consequently affect their market price. Therefore, the objectives of this study were: (1) to assess relationships between price ratio and carcass merit of cull dairy cows sold through several sites of an auction market and (2) to investigate the effect of animal life history events and live weight on sale barn price (BP) and price ratio (as a measure of relative price), as an indicator of carcass merit. Data from 4 dairy operations included 3,602 cull dairy cow records during the period of 2015 to 2019. Life history events data were collected from each dairy operation through Dairy Comp software; live weight and price were obtained periodically from the auction market, and the carcass data were provided by a local packing plant. Cow price in dollars per unit of live weight ($/cwt) and price ratio were the 2 outcome variables used in the analyses. Price ratio was created aiming to remove seasonality effects from BP (BP divided by the national average price for its respective month and year of sale). The association between price ratio and carcass merit traits was investigated using canonical correlation analysis, and the effect of life history events on both BP and price ratio was inferred using a multiple linear regression technique. More than 70% of the cows were culled in the first 3 lactations, with an average live weight of 701.5 kg, carcass weight of 325 kg, and dressing percentage of 46.3%. On average, cull cows were sold at $57.0/cwt during the period considered. The canonical correlation between price ratio and carcass merit traits was 0.76, indicating that price ratio reflected carcass merit of cull cows. Later lactations led to lower BP compared with cows culled during the first 2 lactations. Injury, and leg and feet problems negatively affected BP. Productive variables demonstrated that the greater milk production might lead to lower cow prices. A large variation between farms was also noted. In conclusion, price ratio was a good indicator of carcass merit of cull cows, and life history events significantly affected sale BP and carcass merit of cull cows sold through auction markets.

During marketing, cattle may be exposed to periods of water deprivation. The impact of water and feed access and health status on the physiological well-being and carcass characteristics of Holstein slaughter cows during preslaughter marketing was studied through analysis of serum components, BW loss percentage, and fresh meat composition. Ninety-one multiparous Holstein cows (609 ± 89 kg mean BW, 2.9 ± 0.5 mean BCS, varying stage of lactation) were purchased over 3 wk in 3 groups (n = 31, 29, and 31) at a terminal market in central Wisconsin. Each cow was screened to determine health status (sick or not sick) and randomly assigned to 1 of 3 water and feed withdrawal treatment pens (AL, ad libitum access to water for 36 h; 18H, 18 h of ad libitum access to water followed by 18 h of water withdrawal; 36H, 36 h of water withdrawal; all 3 treatments included 36 h of feed withdrawal) in a randomized complete block arrangement with repeated measures for serum components. Blood samples were collected by tail venipuncture at 0, 9, 18, 27, and 36 h of each treatment. Ambient temperatures were 1.9 ± 6.2°C during the trial period, which occurred over a 3-wk period in March and April 2007 near Arlington, WI. No difference (P > 0.05) was observed in mean serum cortisol in AL (18.41 ± 2.17 ng/mL) or 36H (22.98 ± 2.17 ng/mL). Mean serum glucose was greater (P < 0.05) in 36H pens (78.15 ± 0.77 mg/dL) than AL (75.91 ± 0.77 mg/dL). Mean serum creatinine was greater (P < 0.05) in 36H pens (0.71 ± 0.03 mg/dL) than AL (0.60 ± 0.03 mg/dL). The 36H pens also displayed increased (P < 0.05) serum albumin, anion gap, Ca, Cl, Na, cholesterol, and aspartate aminotransferase over AL. Greater (P < 0.05) mean percentage BW loss was observed in 36H pens (5.2 ± 0.6%) than AL (3.1 ± 0.6%). Mean muscle protein (%) was greater (P < 0.05) in 36H (22.2 ± 0.4%) than 18H (21.3 ± 0.4%). Mean muscle moisture (%) was greater (P < 0.05) in AL and 18H (75.3 ± 0.4% and 75.2 ± 0.4%) than 36H. Mean 24-h pH values were 5.92 (AL), 5.92 (18H), and 5.81 (36H; SE = 0.04) and were not different (P < 0.05). Observed pH and color values indicated a borderline dark-cutter state across all cattle in the study, regardless of water and feed access treatment. Based on these results, water and feed withdrawal in lairage should not exceed 18 h during the marketing of Holstein slaughter cows acclimated to springtime conditions to maintain BW, serum component concentrations, and fresh meat composition.

The objective of this work was to compare feedlot performance, carcass characteristics, and beef sensory attributes from steers finished with diets based on corn, high-tannin sorghum (HTS), and a mix of both grains. Angus crossbred steers (n = 11 steers per treatment, initial BW = 404 +/- 18 kg) were finished on diets containing 765 g/kg of DM of corn, HTS, or a 1:1 mix of corn and HTS. Final BW (P or = 0.72). Multivariate ANOVA indicated a difference in sensory attributes of beef from corn and HTS steers (Wilks' Lambda, P = 0.04). When evaluating each sensory attribute independently, panelists found beef from steers fed HTS to be less juicy (P < 0.01), less tender (P = 0.03), and more cooked (P < 0.01) than beef from animals fed corn. Data from this study indicated that by using a 1:1 mix of HTS and corn it is possible to finish steers to similar BW and carcass quality as by using a corn-based diet. Also, total replacement of corn by HTS in the diets produced lighter and leaner animals. Total replacement of corn by HTS in the finishing diet changed beef sensory attributes, reducing the perception of beef tenderness and juiciness by panelists but without changing instrumental tenderness.

Effects of dietary vitamin E supplementation on drip loss, cooking loss, and muscle fiber disruption in fresh beef loin steaks from Holstein and crossbred beef steers were studied. Nine Holstein steers and nine beef steers were fed a control diet and nine Holstein steers and eight beef steers were supplemented daily with 298 IU of vitamin E/kg of diet for 211, 232, or 252 d. Drip loss, cooking loss, cooking yield, and shear value were measured in each longissimus lumborum sample displayed in PVC film for 2, 6, 10, or 14 d. Dietary vitamin E supplementation produced meat that had smaller (P < .001) increases in drip loss during 14 d of display but higher (P < .01) cooking losses. Cooking yield was reduced (P < .05) by vitamin E supplementation. Vitamin E supplementation reduced (P < .01) muscle cell disruption in beef steak displayed for 14 d. These results indicated that dietary vitamin E treatment stabilized cell integrity and enhanced the ability of beef steak to hold sarcoplasmic components during display, although subsequent losses due to cooking were greater.

Effects of dietary supplementation and postmortem addition of vitamin E on pigment and lipid stability in raw ground beef were examined in this study. Six Holstein steers were fed a control diet for 232 or 252 d and six Holstein steers were supplemented with 1,500 IU of vitamin E per animal daily for 232 or 252 d. Three aliquots of ground beef from each longissimus lumborum were allotted to the following postmortem treatments: no addition (NO), white mineral oil (OIL), and white mineral oil containing sufficient D-alpha-tocopherol to equal the mean difference of alpha-tocopherol concentration between beef from supplemented and control steers (OIL + E). Metmyoglobin percentages and 2-thiobarbituric acid reactive substances values were determined at d 1, 3, 5, 7, and 9 after postmortem treatment. Dietary vitamin E supplementation delayed metmyoglobin increase and highly suppressed lipid oxidation in ground beef during 9 d of display compared with the control. The postmortem addition of vitamin E (OIL + E) was slightly effective in retarding the oxidation of pigment and lipid, especially compared with the OIL treatments. Endogenous vitamin E improved pigment and lipid stability much better than exogenous vitamin E.

Three experiments were conducted to examine the effects of vitamin E supplementation on feedlot cattle. Vitamin E supplementation did not affect feedlot performance or carcass characteristics of cattle fed a high-concentrate diet (P greater than .1). The major finding was the effectiveness of vitamin E in extending the color stability of displayed beef (P less than .01). Color stability during display of longissimus lumborum steaks from cattle supplemented with 300 IU/d for 266 d, 1,140 IU/d for 67 d, or 1,200 IU/d for 38 d was extended by 2.5 to 4.8 d. Gluteus medius steaks had an extended color display life of 1.6 to 3.8 d. The accumulation of lipid oxidation products, but not aerobic microbes, associated with displayed longissimus lumborum was suppressed for muscle from vitamin E-supplemented steers. Taste panelists detected no difference among longissimus lumborum steaks from control and vitamin E-supplemented steers but found (P less than .01) steaks aged for 21 d to be more tender than steaks aged for 7 d. Supplementing cattle with vitamin E should reduce economic losses associated with discolored beef during retail display.

A simplified method for the determination of alpha-tocopherol concentration in beef muscle was developed and evaluated. The method consists of a saponification step applied to 1-g samples of intact, fresh muscle, followed by a single isooctane extraction of the saponified samples. alpha-Tocopherol in the extract was separated by normal phase chromatography and quantified by fluorescence detection. A single extraction with the simplified method accounted for 95% of the total muscle alpha-tocopherol concentration obtained by two extractions with the Arnold et al. (J. Food Sci. 58:28, 1993) method. Recovery of added alpha-tocopherol standard after two extractions of a saponified muscle sample was 91% for the simplified method, which was not different (alpha = .78) from recovery using the Arnold method, and the efficiency of the single extraction in the simplified method was 89%. The coefficients of variation for the simplified and Arnold methods were both 3.1%. This method should permit the duplicate analysis of 100 fresh muscle samples within 24 h.

Pigment and lipid oxidations were investigated in longissimus lumborum (LL), semimembranosus (SM), and gluteus medius (GM) from Holstein steers fed four doses of vitamin E (64 [control], 295, 550, or 2,173 IU/d) for two durations (42 or 126d). Vitamin E dose did not affect (P = .30) carcass quality or yield characteristics. The LL was stored in vacuum packages at 4 degrees C for 14, 28, and 56 d, and GM and SM were stored for 14 d. Increments of dose and duration of vitamin E supplementation increased (P.001) alpha-tocopherol concentration in blood plasma and in these muscles. During simulated retail display, accumulations of metmyoglobin (METMB) and thiobarbituric acid reactive substances (TBARS) were greater (P.01) in beef from control than in beef from supplemented steers. In cubic models, muscle alpha-tocopherol accounted for 79% of the variation in TBARS and 66% of the variation in METMB. Color display life, calculated by the METMB threshold method, revealed fewer dose and duration effects of vitamin E than were evident following analysis of variance of the METMB responses. Across durations and muscles, color display-life of fresh beef calculated by the METMB threshold method was extended (P.05) .9 to 1.8 d by vitamin E supplementation (P.05). Storage for 28 or 56 d caused only a slight decline (P.001) in LL alpha-tocopherol concentration but diminished (P.05) vitamin E effects on color display-life. Although the ranking of alpha-tocopherol accumulation was GMSMLL, the color display-life ranking of these muscles across vitamin E treatments was LLSMGM.

Color stability was investigated in longissimus lumborum (LL), semimembranosus (SM), and gluteus medius (GM) muscles from Holstein steers fed diets including doses of alpha-tocopheryl acetate that were 0 (EO), 250 (E250), 500 (E500), and 2,000 (E2000) mg.steer-1.d-1 for 42 or 126 d. Longissimus lumborum was aged for 14, 28, and 56 d and GM and SM were aged for 14 d. Effects of vitamin E dose on retention of redness (a*), yellowness (b*), color saturation (chroma), and proportions of redness and yellowness (hue angle) following an aging period of 14 d were E2000E500 = E250EO (P.01). Effectiveness of dose duration on the color parameters was 126 d42 d (P.01). Dietary vitamin E supplementation stabilized redness and color saturation, decreased yellowness, and extended color display life of fresh beef. A technique for estimation of color display life based on hue angle measurements of fresh beef is described. Color display life estimates based on hue angle measurements were more consistent with vitamin E supplementation effects on metmyoglobin percentage and hue angle than were estimates obtained from the metmyoglobin threshold method. Color display life across LL, SM, and GM stored until d 14 and then displayed under simulated retail conditions was extended (P.01) 2.0 (E250) to 5.0 d (E2000). Coefficients of determination for regressions of color display life on muscle alpha-tocopherol concentration were .81, .64, and .63 in LL, SM, and GM muscles aged 14 d, respectively. Supplementation of 500 mg of alpha-tocopheryl acetate per steer daily improved (P.01) the mean color display life of these three muscles by 2.3 d, or 100%.

Color is a primary factor used by consumers to judge beef quality, especially freshness. Recent studies indicate that dietary supplementation of vitamin E to beef cattle increases the alpha-tocopherol concentration in muscle and its membranous subcellular fractions. The increased tissue alpha-tocopherol concentration protects not only membranal lipids but also myoglobin from oxidation. This results in delayed onset of discoloration in fresh, ground, and frozen beef and in suppression of lipid rancidity, especially in fresh, ground, and frozen beef and less so in cooked beef. Extension of beef color display life depends on dose level and duration of dietary vitamin E, muscle, and aging period. Cumulative results of experiments conducted to date indicate that beef from animals that receive 500 IU/steer daily of vitamin E for 126 d could assuredly benefit the domestic retail market by extending color display life. Implementation of this technology by the beef industry requires development of a method for rapid determination of alpha-tocopherol concentration in muscle samples collected on the day of harvest.

Dietary supplementation of livestock with vitamin E results in improved quality of meat subsequently obtained from these animals. The effect is especially noteworthy in cattle, in which the primary effects are delayed discoloration and lipid oxidation. A threshold level of alpha-tocopherol in muscle ensures a detectable effect; dietary strategies for attaining this threshold must consider tocopherol status of cattle arriving at the feedyard and duration and level of supplementation. The alpha-tocopherol concentration in muscle must be determined before proper interpretation of experimental results can be made. Muscles vary in their color stability, and this relative difference is not changed by vitamin E supplementation. Several in vitro models have been used to characterize the interaction between alpha-tocopherol, lipid oxidation, and oxymyoglobin oxidation. Alpha-tocopherol seems to exert its color-stabilizing effect by indirectly delaying oxymyoglobin oxidation via direct inhibition of lipid oxidation. However, recent results demonstrating a protective effect of alpha-tocopherol toward oxymyoglobin in low-oxygen atmospheres indicate that additional mechanisms may exist. A better understanding of the fundamental bases for protection of water-soluble myoglobin by lipid-soluble alpha-tocopherol is needed to optimize this beneficial effect.