Effects of dietary potato by-product and rumen-protected histidine on growth, carcass characteristics and quality attributes of beef

Meat Science 107 (2015) 64–74

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Effects of dietary potato by-product and rumen-protected histidine on growth, carcass characteristics and quality attributes of beef☆ K.J. Thornton a,⁎, R.P. Richard a, M.J. Colle a, M.E. Doumit a, M.J. de Veth b, C.W. Hunt a, G.K. Murdoch a a b

Department of Animal and Veterinary Sciences, University of Idaho, Moscow, ID 83844, United States Balchem Corporation, New Hampton, NY 10958, United States

a r t i c l e

i n f o

Article history: Received 16 September 2014 Received in revised form 6 April 2015 Accepted 13 April 2015 Available online 20 April 2015 Keywords: Beef Color stability Histidine Potato by-product Warner–Bratzler shear force

a b s t r a c t We hypothesized that variable composition in finishing rations, more specifically; the proportion of potato-byproduct (PBP) and rumen protected histidine (His) supplementation may influence growth and meat quality attributes. Two different diets were fed (1) finishing ration with corn and barley as grains (CB, n = 20) and (2) substitution of 10% corn, DM basis, with PBP (PBP, n = 20). Additionally, half of each dietary treatment received 50 g/hd/d rumen protected His (HS, n = 20) while the other half received no supplement (NS, n = 20). Inclusion of 10% PBP or HS did not affect growth or carcass traits. Color stability was analyzed using Hunter color values as well as AMSA visual appraisal in both longissimus thoracis (LT) and gluteus medius (GM) muscles. The LT, but not the GM, of CB steers was more color stable over a 9 d simulated retail display compared to those fed a PB diet. Steers receiving HS produced significantly (P b 0.05) more color stable LT and GM steaks. © 2015 Elsevier Ltd. All rights reserved.

1. Introduction Rising feed costs along with competition for available commodities continues to drive consideration of alternate feedstuff in diets. In 2008 processing of frozen potato products produced approximately 4.3 million t (as-is basis) of potato by-product in the United States and Canada (Nelson, 2010). This potato by-product (PBP) can be fed to livestock. However, it is imperative for maintaining sustainability and consumer satisfaction that there are no negative impacts on growth, carcass traits or meat quality. Currently, there are conflicting reports regarding feedlot performance when PBP is included in beef rations. Potato byproduct was reported to have no effect on ADG, feed efficiency or carcass characteristics until the inclusion of PBP exceeded 51.9% of DM in barley-based diets (Hanks, Heinemann, & Young, 1978). Further, inclusion of 10% ensiled potato pieces in corn-based finishing diets increased DMI, ADG and marbling (Nelson, Busboom, Cronrath, Falen, & Blankenbaker, 2000). However, Radunz et al. (2003) found that inclusion of PBP at 10, 20, 30 or 40% of DM decreased feedlot performance but had little effect on carcass or meat quality. This study was implemented to determine effects of including PBP in feedlot diets and further test performance of finishing beef cattle provided with up to 10% PBP in the ration. ☆ We gratefully acknowledge the financial support of this research by the Idaho Beef Council through the Beef Check off Program (IBC FY2011-BGK009) and the University of Idaho's Steer-a-Year Program for use of research steers. ⁎ Corresponding author at: 368 ABLMS, University of Minnesota, St. Paul, MN 55108, United States. Tel.: +1 208 989 1588. E-mail address: [email protected] (K.J. Thornton).

http://dx.doi.org/10.1016/j.meatsci.2015.04.009 0309-1740/© 2015 Elsevier Ltd. All rights reserved.

Histidine (His) is known to be a limiting AA for growing cattle (Chalupa, Chandler, & Brown, 1973; Greenwood & Titgemeyer, 2000). Several studies have shown that provision of His to lactating dairy cows increases milk and milk protein yield (Huhtanen, Vanhatalo, & Varvikko, 2002; Little, 1975; Vanhatalo, Huhtanen, Toivonen, & Varvikko, 1999). Additionally, His and its metabolites; carnosine and anserine, have been shown to have antioxidant properties (Boldyrev, Dupin, Pindel, & Severin, 1988; Wade & Tucker, 1998). However, we are not aware of any studies that have reported the effects of providing supplemental His to feedlot steers on growth, carcass and meat quality characteristics. We hypothesize that in rapidly growing finishing cattle, dietary histidine availability may be limiting rates of lean body gain and further that increased histidine availability will increase color stability of meat in association with enhanced storage of the anti-oxidant histidine metabolites distributed in muscle. Objectives of this study are; (1) evaluate differences in growth, carcass traits and meat quality in feedlot steers fed either a diet with corn and barley as grains or a diet with 10% of the corn substituted for PBP and (2) evaluate the effects of providing rumen protected His to feedlot steers on growth, carcass traits and beef quality. 2. Materials and methods 2.1. Animal care All animal procedures were reviewed and approved by the Institutional Animal Care and Use Committee (IACUC) as required by federal law and University of Idaho policy.

K.J. Thornton et al. / Meat Science 107 (2015) 64–74

2.2. Animals & diets

65

Table 2 Nutrient composition of potato by-product, hopper waste, used in finishing ration.

Forty steers were obtained from the University of Idaho's Steer-AYear program. Steers came from producers across Idaho and were received at the University of Idaho. Steers utilized in the trial had Angus, Charolais, Hereford and Simmental breeding, typical of cattle raised in this area, and were approximately 7–9 mo of age upon being received. Steers were received over a two month period and were fed the same back-grounding ration upon arrival until commencement of the trial. Treatment groups included steers finished on a conventional ration within the US with the grains being corn and barley (CB, n = 20) or a diet with 10% potato by-product substituted for corn (PB, n = 20); diet composition and nutrient analysis can be seen in Table 1. This study utilized hopper waste as the potato by-product, specific nutrient composition of the hopper waste utilized in this study can be seen in Table 2. Further, half of the animals in each of the diet treatments were supplemented with 50 g/hd/d of rumen protected His (no His supplementation, NHS, n = 20 or receiving histidine supplementation, HS, n = 20). The His product (Balchem Corporation, New Hampton, NY) contained 40% His and has been shown to be highly rumen protected and bioavailable in the ruminant (Little, 1975; Patton & Parys, 2012). Further, it was estimated that 25 g/d of His on the CB diet and 24 g/d of His in the PB diet were flowing to the small intestine as predicted by Model II of the Beef NRC (NRC, 1996). Steers were initially weighed and placed into one of 4 different treatment groups (10 steers per treatment) at random. Animals from different treatment groups were randomly allocated to 1 of 8 different pens with 5 steers per pen. Pens had a concrete floor and steers were bedded with sawdust. All animals were branded, dewormed and vaccinated with Pyramid5® (Boehringer Ingelheim, Ridgefield, CT) and Caliber7® (Boehringer Ingelheim). Subsequently, animals were implanted with Revalor S® (Merck Animal Health, Summit, NJ) and moved into pens 5 mo prior to harvest. Steers were trained to use Calan gates (American Calan, Northwood, NH) over a 2 week period and the feed trial commenced approximately 5 mo prior to expected harvest date. Steers were fed ad libitum twice daily at 0700 and 1600. His was individually pre-measured and top dressed on the ration each morning. Animals were weighed bi-weekly prior to the morning feeding during the trial. The finishing period lasted for 129 d. Animals were then transported to Washington Beef in Toppenish, WA in a single load and harvested the following morning.

Item

Dry-basis, %

As received, %

Moisture Dry matter Protein, crude Fat (EE) Ash

– – 8.83 0.74 11.66

77.45 22.55 1.99 0.17 2.63

2.3. Carcass data collection Hot carcass weight was recorded by Washington Beef and carcass data were acquired by trained personnel from the University of Idaho. Rib eye area (REA), kidney, pelvic and heart fat (KPH), marbling score, quality grade and final yield grade (YG) were determined approximately 24 h after harvest. USDA Quality Grade was also determined for each carcass by Washington Beef via the VBG2000 Vision Camera.

2.4. Preparation of steaks for beef quality measurements After processing, the vacuum packaged strip loin (IMPS/NAMP 180, 2010) from the left side from each carcass was obtained and transported on ice to the UI Moscow campus meat science laboratory for aging and post-harvest processing. These samples were used for analyses of color (Hunter MiniScan EZ, Restin, VA), Warner–Bratzler shear force (WBSF) (GR Manufacturing, Manhattan, KS) and HPLC metabolite analysis (Waters e2695 and a Waters 2998 photodiode array detector, Milford, MA, USA). On d-14 post-mortem, wholesale cuts were removed from the vacuum packages. The anterior end of the strip loin was prepared by removing a slice approximately 2 cm-thick, perpendicular to the long axis of the longissimus muscle. Subsequently, two 2.54 cm-thick steaks were removed from the anterior end for analysis of longissimus thoracis (LT) color and WBSF. A 2.54 cm-thick steak from the posterior end of the strip loin was used for analysis of gluteus medius (GM) color. Steaks from the LT and GM muscles were chosen for their known differences in color stability (Renerre, 1984). Steaks for WBSF were transported to the UI food science lab. Steaks for color analysis during retail display were packaged in white styrofoam trays with an oxygen permeable PVC overwrap (Koch Industries, Inc #7500-3815; Wichita, KS) and allowed to bloom for at least 20 min.

2.5. pH determination Table 1 Composition and chemical analysis (DM basis) of the two different finishing diets. Item Ingredient, % Feeder alfalfa Potato by-product Apples Dried distillers grains Corn Barley Performix supplement Chemical analysis DM, % as fed CP, % Crude fiber, % Fat, % Ash, % NEm Mcal/lb NEg Mcal/lb TDN, % Nitrogen free extract, % a b

Potato-baseda

Corn-basedb

9.20 10.00 9.00 14.00 22.20 30.80 4.80

9.20 – 9.00 14.00 32.20 30.80 4.80

60.69 13.68 11.46 4.40 6.12 0.87 0.55 76.49 64.34

68.24 13.39 10.85 3.69 5.16 0.90 0.58 78.58 67.36

10% potato-by product substituted for corn. Conventional finishing ration in the US with corn and barley as grains.

Muscle pH was measured on d14 immediately after fabrication. A portable pH meter (Model 1140, Mettler-Toledo, Woburn, MA) equipped with a puncture-type electrode was used to measure pH of the LT from the anterior end of the strip loin and the GM from the posterior end of the strip loin. The pH meter was calibrated using standard pH 4.0 and 7.0 buffers chilled to 4 °C. Two pH measurements were recorded for each steak and an average of these two values was reported.

2.6. Warner–Bratzler shear force determination Steaks from the anterior end of the strip loin were weighed and cooked on open-hearth broilers to an internal temperature of 40 °C, then turned and cooked to a final internal temperature of 71 °C. Steaks were re-weighed to determine cooking loss and allowed to cool to room temperature. Six cores (1.27 cm diam.) were mechanically removed parallel with the muscle fiber orientation using a drill press-mounted coring device, and shear force was determined by shearing each core perpendicular to the muscle fibers using a Warner–Bratzler shear machine. The average WBSF value of the six cores ± SEM is reported.

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2.7. Hunter L*, a* and b* and AMSA color evaluation All steaks were displayed in a glass retail display case (Model GDM69, True Manufacturing Co., O'Fallon, MO) at 2 °C. The display case was equipped with natural white Hg 40 W lights, and the average light intensity was 408 lx. To avoid affects due to location, steaks were rotated after each measurement. Hunter color measurements were taken on d 0, 1, 3, 5, 7 and 9 of retail display. Two objective color measurements were taken per steak on the LT and one measurement was taken on the GM. Only one measurement was taken of the GM on the posterior steak due to the small size of this muscle. This instrument is equipped with a 25-mm diameter measuring window and a 10° standard observer. The instrument was set to illuminant A and Commission International de l'Eclairage (CIE) L*, a* and b* duplicate values were recorded from two different locations on the LT and one location on the GM. Calibration of the machine was carried out each day by measuring against black and white calibration tiles, as suggested by the manufacturer. Hue angle was calculated as tan−1 a*/b* (Wheeler, Koohmaraie, & Shackelford, 1996). Two evaluators scored steaks for discoloration (1 = none; 5 = extreme), surface discoloration (0% = no discoloration; 100% = total discoloration), amount of browning (1 = no evidence of browning; 6 = dark brown) and color uniformity (1 = uniform; 5 = extreme two-toning) on d 0, 1, 3, 5, 7 and 9 after being re-packaged for retail display following AMSA meat evaluation guideline (AMSA, 1991). 2.8. Preparation of muscle extracts for metabolite analysis Approximately, 5 g wet weight LT samples were collected from the LT 14 d post-mortem and snap frozen in liquid nitrogen until time of analysis. Tissues were ground using a mortar and pestle and stored under liquid nitrogen. Free AA was extracted as per Aristoy and Toldra (1991). In brief, approximately 250 mg tissue was homogenized with 0.01 N HCl at a 1:4 dilution using a Retsch Bead Homogenizer MM301 (Retsch, Newtown, PA, USA), for 5 × 20 s at 25 Hz. Following homogenization, samples were centrifuged at 10,000 g for 20 min at 4 °C. The supernatant was then filtered through glass wool and stored at −80 °C until further analysis. 2.9. Deproteinization and derivatization of muscle extracts for metabolite analysis Samples were deproteinized by following the methods of Aristoy and Toldra (1991). In brief, 50 μL of hydroxyproline (0.325 mg/ml) and 750 μL acetonitrile were added to 250 μL of thawed sample and allowed to stand at room temperature for 30 min (Aristoy & Toldra, 1991). Hydroxyproline (Sigma Aldrich, St. Louis, MO, USA) was used as an internal standard. Samples were centrifuged at 10,000 g for 15 min at 4 °C. Two hundred microliters of the centrifuged samples was immediately

derivatized following the methods of Bidlingmeyer, Cohen, Tarvin, and Frost (1987). In brief, samples were dried at 38 °C under vacuum and nitrogen in a Waters Pico Tag Work Station (Waters). Twenty microliters of methanol–1 M sodium acetate–triethanolamine (TEA) (2:2:1) was added to the samples and dried under vacuum and nitrogen. Samples were derivatized by adding 20 μL of methanol–water–TEA–phenyl isothiocyanate (PITC) (7:1:1:1) and allowed to stand at room temperature for 20 min. Samples were then again dried under vacuum and nitrogen. One hundred microliters of 5 mM sodium phosphate pH 7.6 with 5% acetonitrile was then added. Samples were immediately analyzed using HPLC following derivatization. All solutions for derivatization were prepared fresh each day. 2.10. HPLC analysis Muscle extracts were analyzed on a Waters e2695 (Waters) separations model equipped with an autosampler and a Waters 2998 photodiode array detector (Waters) set to 254 nm. The column was a Waters Symmetry® C18 3 × 150 mm (5 μM particle size). The temperature of the column was controlled at 40 °C ± 1 °C with a column heater. HPLC method used was adapted from Aristoy and Toldra (1991). In brief, two eluents were used in the solvent system: (A): 0.14 M sodium acetate containing 0.5 mL/L of TEA at pH 6.4 adjusted with glacial acetic acid; and (B) acetonitrile–water 60:40. The flow rate was set to 0.8 mL/min and the following gradient was performed: initial 10% B, 6 min linear change to 12.5% B, 32 min linear to 58% B, 33 min step to 100% B; wash for 8 min and re-equilibrate to 10% B during 20 min before a new injection. Twenty microliters of samples or standards was injected into the system. Waters Empower pro software (Waters) was used for detection of metabolites. Four different standards were used; hydroxyproline, L-anserine, L-carnosine and L-histidine (Sigma Aldrich, St. Louis, MO, USA) and analyzed at levels from 0 mg to 2 mg. All samples were run in duplicate and quantified based on comparison to standard curve; all standard curves had an R2 of at least 0.95. Free histidine, carnosine and anserine values are reported as mg/g wet tissue weight. 2.11. Statistical analyses Statistical analysis of the data was completed using the Proc. Mixed procedures of SAS software (Statistical Analysis Software version 9.2, Cary, NC, USA). Statistical comparisons were performed between the animals from each of the four treatment groups (diet treatment N = 40, supplement treatment N = 40). “Animal” was the experimental unit in all analyses as data for measurements were collected at the individual animal level. A mixed statistical model was utilized for analysis treating the animal as a random variable and diet, supplement and the interaction between diet and supplement as fixed variables. Pen number was included in the original statistical model however, there were no significant (P N 0.05) differences found relative to this variable and

Table 3 Growth traits of steers during final 129 d finishing. Treatment Diet

Supplement 1,§

ADG, kg/d G:F Total DMI, kg Starting BW, kg End BW, kg

2,§

Corn-based

Potato-based

1.7 ± 0.04 0.166 ± 0.004 1373 ± 54.0 371 ± 12.2 585 ± 13.2

1.6 ± 0.04 0.165 ± 0.004 1330 ± 53.5 366 ± 12.2 570 ± 13.2

P-value⁎

Histidine3,§

No histidine4,§

P-value⁎

0.22 0.86 0.39 0.71 0.43

1.7 ± 0.04 0.165 ± 0.004 1361 ± 55.0 367 ± 12.1 578 ± 13.2

1.6 ± 0.04 0.165 ± 0.004 1361 ± 52.51 370 ± 12.3 578 ± 13.2

0.65 0.98 0.72 0.82 0.99

§ Values represent average ± SEM. ⁎ P-values shown represent the fixed effect of either diet or supplement. There were no significant (P N 0.05) interactions between diet or supplement, these values are not shown. 1 Conventional finishing ration in the US with corn and barley as grain, N = 20. 2 10% potato-by product substituted for corn, N = 20. 3 Supplementation of 50 g/hd/d of rumen protected histidine, N = 20. 4 No histidine supplementation, N = 20.

K.J. Thornton et al. / Meat Science 107 (2015) 64–74

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Table 4 Carcass and end-product quality data of steers. Treatment Diet

HCW, kg BF, in Preliminary yield grade REA, in2 KPH, % Final yield grade Marbling‡ WBSF, kg/cm3 LT pH# GM pH#

Supplement

Corn-based1,§

Potato-based2,§

P-value⁎

Histidine3,§

No histidine4,§

P-value⁎

341.3 ± 8.4 0.4 ± 0.039 3.19 ± 0.10 12.58 ± 0.29 2.30 ± 0.10 2.81 ± 0.14 464.5 ± 22.2 2.61 ± 0.10 5.57 ± 0.008 5.57 ± 0.006

334.0 ± 8.4 0.4 ± 0.039 3.17 ± 0.10 12.17 ± 0.29 2.23 ± 0.10 2.89 ± 0.14 470.5 ± 22.2 2.30 ± 0.10 5.59 ± 0.008 5.57 ± 0.006

0.54 0.87 0.86 0.33 0.58 0.71 0.85 0.04⁎ 0.26 0.62

335.7 ± 8.4 0.4 ± 0.039 3.21 ± 0.10 12.41 ± 0.29 2.18 ± 0.10 2.81 ± 0.14 472.0 22.2 2.53 ± 0.10 5.58 ± 0.008 5.57 ± 0.006

339.6 ± 8.4 0.4 ± 0.039 3.15 ± 0.10 12.34 ± 0.29 2.35 ± 0.10 2.88 ± 0.14 463.0 ± 22.2 2.38 ± 0.10 5.58 ± 0.008 5.57 ± 0.006

0.75 0.91 0.65 0.86 0.21 0.71 0.78 0.31 0.79 0.78

⁎ P-values shown represent the fixed effect of either diet or supplement and are significant P ≤ 0.05. There were no significant (P N 0.05) interactions between diet and supplement, these values are not shown. § Values represent average ± SEM. 1 Conventional finishing ration in the US with corn and barley as grain, N = 20. 2 10% potato-by product substituted for corn, N = 20. 3 Supplementation of 50 g/hd/d of rumen protected histidine, N = 20. 4 No histidine supplementation, N = 20. ‡ Marbling score was provided by Washington Beef with marbling scores ranging from 300, indicating a slight degree of marbling and a quality grade of select, to 999, indicating an abundant degree of marbling and a quality grade of prime. # pH values reported in the longissimus thoracis (LT) and gluteus medius (GM) were taken after 14 d aging period, immediately before retail packaging.

as such, this variable was removed for final statistical analyses. There were no significant (P N 0.05) interactions between diet and supplement detected using a linear model and as such only the data for the main effects of diet or histidine supplementation are reported in the subsequent results. Least squares means were determined using Tukey adjustments. This model was utilized to analyze ADG, G:F, DMI, free His, anserine, carnosine and all carcass trait measurements. Growth and color analyses; both Hunter color values and visual appraisal of both the LT and GM, were analyzed using repeated measures with animal as a random variable and diet, supplementation and day as well as the interactions between diet and supplement, diet and day, supplement and day and the three way interaction between day, diet and supplement as fixed effects. There were no significant (P N 0.05) interactions detected between diet and supplement, diet and day, supplement and day or the three way interaction between day, diet and supplement in any color or visual appraisal analysis. P-values of ≤ 0.05 were considered statistically significant and P-values ≤ 0.10 were considered trends in the data. All data are presented as least squares means ± SEM.

Further, analysis with repeated measures demonstrated no difference in growth by diet (P = 0.11) or HS (P = 0.63) treatments. Further, no differences (P N 0.10) were detected in ADG, G:F, total DMI, starting BW or end BW in steers receiving HS vs NHS (Table 3).

3. Results

3.3. Metabolite content in the LT

3.1. Growth traits

Total free His, anserine and carnosine levels were measured in the LT after 14 d aging. Steers finished on a PB diet had more His (P = 0.04) and anserine (P = 0.02) and tended to have more carnosine (P = 0.08) when compared to steers finished on a CB diet (Table 5). There

3.2. Carcass and meat quality No differences (P N 0.10) were detected in HCW, BF, PYG, REA, KPH, FYG or marbling score in steers fed a CB vs. a PB diet (Table 4). There were also no differences (P N 0.10) in pH of the LT or GM taken after 14 d aging in either the diet or supplement treatment groups (Table 4). However, steers finished on a CB diet had a greater (P = 0.04) WBSF indicating that steers finished on a PB diet resulted in a LT that was more tender after 14 d aging (Table 4). Additionally, no differences (P N 0.10) were detected in HCW, BF, PYG, REA, KPH, FYG, marbling score or WBSF values in steers receiving HS vs. NHS during the finishing period.

Feedlot steers fed a CB vs. PB finishing diet exhibited no differences (P N 0.10) in ADG, G:F, total DMI, starting BW or ending BW (Table 3). Table 5 Free histidine, carnosine and anserine in the LT 14 d after harvest. Treatment Diet Corn-based Histidine Anserine Carnosine †

Supplement 1,§

0.095 ± 0.006 0.085 ± 0.018 0.089 ± 0.010

Potato-based

2,§

0.113 ± 0.006 0.146 ± 0.018 0.114 ± 0.010

P-value 0.04⁎ 0.02⁎ 0.08

†

¥

Histidine3,§

No histidine4,§

P-value¥

0.107 ± 0.006 0.128 ± 0.018 0.099 ± 0.010

0.101 ± 0.006 0.103 ± 0.018 0.104 ± 0.010

0.43 0.34 0.74

P-values show tendencies P ≤ 0.10. ⁎ P-values are significant P ≤ 0.05. ¥ P-values shown represent the fixed effect of either diet or supplement. There were no significant (P N 0.05) interactions between diet or supplement, these values are not shown. § Metabolite values indicate average mg/g wet weight tissue ± SEM. 1 Conventional finishing ration in the US with corn and barley as grain, N = 20. 2 10% potato-by product substituted for corn, N = 20. 3 Supplementation of 50 g/hd/d of rumen protected histidine, N = 20. 4 No histidine supplementation, N = 20.

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were no differences (P N 0.10) found in the concentrations of free His, anserine or carnosine in the LT of steers receiving HS vs. NHS (Table 5).

3.4. Color stability The different diets resulted in LT steaks that had no difference (P N 0.10) in the L*, a* or b* values (Fig. 1). Additionally, there were no dietary treatment differences (P N 0.10) in the hue angle of the LT, data not shown. However, steers fed a CB diet vs. a PB diet had less

(P ≤ 0.03) visual browning, discoloration, surface discoloration and improved uniformity in the LT steaks over the 9 d simulated retail display (Fig. 5). Color stability was measured in the GM following the same procedures as the LT. There were no differences (P N 0.10) detected in the L*, a* or b* values of the GM steaks over the 9 d simulated retail display resulting from different finishing diet (Fig. 3). There were no differences (P N 0.05) in the hue angle detected. Further, there were no differences resulting from different finishing diets (P N 0.05) in browning, discoloration, surface discoloration or color uniformity detected in the GM throughout the 9 d simulated retail display (Fig. 7).

50 50

Corn-Based Diet Potato-Based Diet

No Histidine Histidine

48

46

L* Color Value

L* Color Value

48

44

42

46

44

42

40 40

38 0

1

3

5

7

38

9

0

34 32

1

3

5

7

9

34

Corn-Based Diet Potato-Based Diet

No Histidine Histidine

32

30

a* Color Value

a* Color Value

30

28 26 24

28 26 24

a

22 22

20

b

20

18 0

1

3

5

7

18

9

0

28 27

3

5

7

9 No Histidine Histidine

27

26

26

25

b* Color Value

b* Color Value

1

28

Corn-Based Diet Potato-Based Diet

24 23

25 24 23

22 22

a

21

b

21 20 0

1

3

5

7

9

Day of Simulated Retail Display

20 0

1

3

5

7

9

Day of Simulated Retail Display Fig. 1. Hunter L* a* and b* color values of the longissimus thoracis of steers finished on either a traditional diet with corn and barley as grains (corn-based) or a diet where 10%, DM basis, potato-by product was substituted for corn (potato-based). Values are represented as mean ± SEM. No differences (P N 0.10) in color values over a 9 d simulated retail display were observed in the fixed effect of diet or any of its interactions with supplement and/or day.

Fig. 2. Effects of supplementation of 50 g/hd/d rumen protected histidine vs. no supplementation on Hunter L* a* and b* color values of the longissimus thoracis. Values are represented as mean ± SEM. Different subscripts indicate differences (P b 0.01) in color values over a 9 d simulated retail display in the fixed effect of supplement. No significant differences were detected in interactions between supplement and/or day and diet.

K.J. Thornton et al. / Meat Science 107 (2015) 64–74

46

69

46 No Histidine Histidine

44

44

42

42

L* Color Value

L* Color Value

Corn-Based Diet Potato-Based Diet

40

38

36

40

38

36

34

34 0

1

3

5

7

9

0

40

1

3

5

7

Corn-Based Diet Potato-Based Diet

No Histidine Histidine

35

35

30

30

a* Color Value

a* Color Value

9

40

25

20

15

25

20

a b

15

10

10 0

1

3

5

7

9

0

32

1

3

5

7

9

30 No Histidine Histidine

Corn-Based Diet Potato-Based Diet

30

28

b* Color Value

b* Color Value

28 26 24 22

26

24

22

a b

20

20 18

18 0

1

3

5

7

9

Day of Simulated Retail Display

0

1

3

5

7

9

Day of Simulated Retail Display

Fig. 3. Hunter L* a* and b* color values of the gluteus medius of steers finished on either a traditional diet with corn and barley as grains (corn-based) or a diet where 10%, DM basis, potato-by product was substituted for corn (potato-based). Values are represented as mean ± SEM. No differences (P N 0.10) in color values over a 9 d simulated retail display were observed in the fixed effect of diet or in any of the interactions with day and/or supplement.

Fig. 4. Effects of supplementation of 50 g/hd/d rumen protected histidine vs. no supplementation on Hunter L* a* and b* color values of the gluteus medius. Values are represented as mean ± SEM. Different subscripts indicate differences (P ≤ 0.05) in color values over a 9 d simulated retail display for the fixed effect of supplement. No significant differences were detected in interactions between supplement and/or day and diet.

No differences (P N 0.10) were observed in the LT between the steers receiving HS vs. NHS in the L* value over the 9 d simulated retail display (Fig. 2). However, there was an increased a* (P = 0.0012) and b* (P = 0.007) value in the LT of steers receiving HS throughout the 9 d simulated retail display (Fig. 2). Further, the hue angle was increased (P = 0.01) in the LT of steers receiving HS, data not shown. Moreover, there was less (P ≤ 0.002) browning, discoloration, surface discoloration and improved uniformity over the 9 d simulated retail display in the LT of steers receiving HS (Fig. 6). Differences in the color stability of the GM steers receiving HS or NHS were also analyzed. There were

no differences (P N 0.10) detected in the L* of the GM over the 9 d simulated retail display (Fig. 4). However, the GM of steers receiving HS had an increased a* (P = 0.004) and b* (P = 0.05) value during the 9 d simulated retail display (Fig. 4). The hue angle was increased (P = 0.01) during the 9 d simulated retail display in the GM from steers receiving HS, data not shown. Further, evaluation of the GM following AMSA color evaluation guidelines demonstrated that there was less (P ≤ 0.01) browning, discoloration and surface discoloration in the steaks from steers receiving HS (Fig. 8). There was no difference (P N 0.10) due to HS in color uniformity detected in the GM (Fig. 8).

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3.5

5

P = 0.01

Corn-Based Diet Potato-Based Diet

P = 0.0015

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Fig. 5. AMSA meat evaluation of browning, discoloration, surface discoloration and uniformity in the longissimus thoracis of steers finished on either a traditional diet with corn and barley as grains (corn-based) or a diet where 10%, DM basis, potato-by product was substituted for corn (potato-based). Values are represented as mean ± SEM. P-values of repeated measures analysis for the fixed effect of diet are indicated in the top right corner of each graph in the figure. No significant differences were detected in interactions between diet and/or day and supplement.

4. Discussion 4.1. Growth traits It was determined that inclusion of 10% PBP of diet DM in a corn and barley based feedlot diet yielded no effect on growth traits in the present study. Previous work indicates that inclusion of PBP up to 51.9% of DM in a barley-based diet had no adverse effects on feedlot growth performance (Heinemann & Dyer, 1972; Hanks et al., 1978). However, Radunz et al. (2003) found that inclusion of steam-peeled PBP at 10, 20, 30 or 40% (DM basis) decreased feedlot performance by lowering both ADG and DMI (N = 125). Stanhope, Hinman, Everson, and Bull (1980) also reported decreased DMI as levels of PBP increased from 0 to 60% of the diet DM in barley-based finishing rations (N = 10). In contrast, other research has demonstrated that inclusion of ensiled PBP in feedlots diets has a tendency (P b 0.10) to increase both ADG and DMI (N = 144) (Nelson et al., 2000). The effects of inclusion of PBP in feedlot diets may result in conflicting results regarding growth performance due to type of PBP included in the diet, differences in other components of the diet and the number and source of animals used in each study. The present study found that supplementation with His resulted in no effect on ADG, G:F, total DMI, starting BW or end BW. Storm and Orskov (1984) found that in sheep ruminal microbes were deficient in His, making it reasonable to hypothesize that provision of His may increase growth performance of cattle through indirect enhancement of microbial digestion. To date, research focusing on the inclusion of

supplemental His for cattle has analyzed the effects on milk production in dairy cattle, but no previous research has analyzed the effects of providing rumen protected His to feedlot cattle. Supplying His to diets deficient in metabolizable His may improve protein deposition by growing cattle (McCuistion, Titgemeyer, Awawdeh, & Gnad, 2004). However, nutritional factors that may alter the efficiency with which His is utilized need to be further determined. We report that provision of 50 g/hd/d of rumen protected His to feedlot cattle did not improve growth traits although there were no adverse effects on growth noted. Further studies with a larger population of research animals are needed to determine the optimal level and timing of His inclusion specific to various finishing rations. 4.2. Carcass and meat quality Feeding a CB vs. a PB diet had no effect on HCW, BF, PYG, REA, KPH, FYG, marbling score or pH in either the LT or GM after 14 d aging. Steers finished on a CB diet had a greater WBSF indicating that steers finished on a PB diet resulted in a LT that was more tender after 14 d aging. It has been previously reported that PBP has no effect on HCW, REA, BF or marbling score (Nelson et al., 2000). Additionally, it has been found that there was no difference in marbling when diets contained 0 to 50% (DM basis) potato slurry (Sauter et al., 1980). However, conflicting reports have shown that PBP inclusion decreased HCW, BF and REA, and that PYG was highest at 0% inclusion of PBP but was similar from 10 to 40% (Radunz et al., 2003). Further, in contrast with the previous study, Busboom et al. (2000) reported no difference in WBSF values of the LT

K.J. Thornton et al. / Meat Science 107 (2015) 64–74

5

71

4

P = 0.0018

No Histidine Histidine

P < 0.001

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60 No Histidine Histidine

P < 0.001

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P = 0.001 3

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40

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Fig. 6. AMSA meat evaluation of browning, discoloration, surface discoloration and uniformity in the longissimus thoracis of steers provided 50 g/hd/d of rumen protected histidine during finishing vs. no provision of histidine supplement. Values are represented as mean ± SEM. P-values of repeated measures analysis for the fixed effect of supplement are indicated in the top right corner of each graph in the figure. No significant differences were detected for the interactions between supplement and/or day and/or diet.

with inclusion of PBP at 0, 10, 20, or 30% DM in the diet. One study has demonstrated that inclusion of PBP in feedlot diets resulted in meat product contamination with pseudomonas, which resulted in a potato-like odor (Daise, Zottola, & Epley, 1986). However, this result was not observed in our study. There are several different types of PBP that can be obtained and fed, making them variable in composition which may explain the differences observed between the present study and others. Histidine supplementation of 50 g/hd/d did not alter HCW, BF, PYG, REA, KPH, FYG, marbling score or WBSF values in steers during the finishing period. No previous research has reported the effects of rumen-protected His on feedlot cattle performance. 4.3. Metabolite content in the LT Steers finished on a PB diet had more His, anserine and carnosine stored within the LT as compared to steers finished on a CB diet. To the knowledge of the authors, inclusion of PBP in feedlot diets has not previously been shown to increase levels of His and antioxidants, anserine and carnosine, in skeletal muscle. Previous research has demonstrated that oxidation reduces calpain mediated proteolysis (Rowe, Maddock, Lonergan, & Huff-Lonergan, 2004). As such, the observed increases in His, anserine and carnosine may be related to the lower WBSF value of the steers finished on a PB ration. Further, this increase may be due to differences in amino acid proportions within the diet allowing for the body to most efficiently store and metabolize His and its metabolites. Inclusion of different feedstuffs in diets determines

which amino acids are limiting, which in turn affects how the body utilizes each amino acid (Huhtanen et al., 2002; Vanhatalo et al., 1999). Further research needs to be performed to determine the specific components in the diet when PBP is included at 10% DM basis that allow steers to store more His, anserine and carnosine in the LT. There were no differences identified in the concentrations of free His, anserine or carnosine in the LT of steers receiving HS vs. NHS. Provision of a β-alanine supplement has been reported to increase carnosine content within skeletal muscle in human patients (Harris et al., 2006; Hill et al., 2007), likely due to reduced carnosine breakdown since β-alanine is a by-product of the degradation of carnosine. Further, Dunnett and Harris (1999) found that supplementation of horses with β-alanine and L-His increased carnosine levels within the GM, however there was no increase in His levels after supplementation. In the present study, supplementation of 50 g/hd/d His during a 129 d finishing period trended towards increased His and anserine levels in the LT, but these differences did not attain statistical significance. Further research would be advantageous in order to determine the fate of dietary His once it has been absorbed due to the complexity of its metabolism, interaction with other amino acids and competition for uptake into skeletal muscle of ruminants. 4.4. Color stability Feeding a CB or PB diet had no effect on the L*, a*, b* or hue angle values in the LT steaks. However, steers fed a CB diet had less visual browning, discoloration, surface discoloration and improved uniformity

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Fig. 7. AMSA meat evaluation of browning, discoloration, surface discoloration and uniformity in the gluteus medius of steers finished on either a traditional diet with corn and barley as grains (corn-based) or a diet where 10%, DM basis, potato-by product was substituted for corn (potato-based). Values are represented as mean ± SEM. No difference (P N 0.10) was detected in the fixed effect of diet or any of its interactions with day and/or supplement.

over the 9 d simulated retail display when compared to steaks from animals fed a PB diet. Additionally, the present study demonstrates that there are no differences resulting from the two different diet treatments regarding color stability of the GM, a typically less color stable meat product. There were no differences detected in the L*, a* or b* values over the 9 d simulated retail display. There were also no differences in the hue angle detected. Further, there were no differences in browning, discoloration, surface discoloration or color uniformity detected in the GM throughout the 9 d simulated retail display. Meat color is one of the most important criteria influencing consumer purchase (Cornforth, 1994; Gatellier, Mercier, Juin, & Renerre, 2005). Oxidation of lipid and protein in meat forms agents known to negatively affect the color and palatability of meat products (Ma, Jiang, Lin, Zheng, & Zhou, 2010). β-Carotene is an antioxidant known to reduce the effects of oxidation. Corn generally has abundant β-carotene, known to interact with free radicals lending to its antioxidant properties. Muramoto, Nakanishi, Shibata, and Aikawa (2003) reported that supplementation of β-carotene (7500 mg/d, 28 d prior to harvest) lengthened color life by 1.5 and 3 d in the semimembranosus and LT, respectively in Japanese black cattle. Further, β-carotene is a pre-cursor of vitamin A, which has been implicated to affect marbling (Gorocica-Buenfil, Fluharty, Bohn, Schwartz, & Loerch, 2007). However, very few studies have analyzed the effects of vitamin A supplementation on color stability. Administration of vitamin A (retinyl palmitate, 60 IU of vitamin A/100 kg bw/d) had no effect on color stability (Kruk et al., 2008). The present study demonstrates that inclusion of corn at increased levels (32.2% DM basis, CB diet) compared to deceased levels (22.2% DM basis, PB diet) resulted in improved color stability in the LT, but not

the GM. We suggest that there was an improvement in color stability in the LT due to increased levels of β-carotene within the muscle acting as an antioxidant, although β-carotene levels were not analyzed in the present study and this result was not observed in the GM. Future research needs to be completed to determine the mechanism behind this finding as well as why there was a lessened effect in the less color stable muscle, the GM. Radunz et al. (2003) found that inclusion of PBP in feedlot diets had no effect on L*, a* or b* values at the time of fabrication. Further, Nelson et al. (2000) found no differences in L*, a* or b* values during a 7 d simulated retail display in the LT. These findings lend to the complexity of shelf-life color stability in beef products with different treatment effect being noted between muscles. Analysis of meat color of steaks from animals receiving HS vs. NHS revealed that there was no difference between the steers receiving HS vs. NHS in the L* value over the 9 d simulated retail display. However, there was an increased a* and b* value in the LT of steers receiving HS throughout the 9 d simulated retail display. Further, the hue angle was increased in the LT of steers receiving HS. Increases in hue angle are indicative of overall improvements in color stability of beef products (Little, 1975; Wheeler et al., 1996). Moreover, there was less browning, discoloration, surface discoloration and improved uniformity over the 9 d simulated retail display in the LT of steers receiving HS. Differences in the color stability of the GM from steers receiving HS or NHS were also analyzed. No differences were present in the L* value, although the LT of steers receiving HS had an increased a* and b* value during the 9 d simulated retail display. The hue angle was also increased during the 9 d simulated retail display in the GM from steers receiving HS. Evaluation of the GM following AMSA color evaluation guidelines showed

K.J. Thornton et al. / Meat Science 107 (2015) 64–74

6

5

P = 0.006

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60

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Fig. 8. AMSA meat evaluation of browning, discoloration, surface discoloration and uniformity in the gluteus medius of steers provided 50 g/hd/d of rumen protected histidine during finishing vs. no provision of histidine supplement. Values are represented as mean ± SEM. P-values of repeated measures analysis for the fixed effect of supplement are indicated in the top right corner of each graph in the figure, there was no difference (P N 0.10) detected in uniformity for this fixed effect. No significant differences were detected in interactions between supplement and/or day and/or diet.

that there was less browning, discoloration and surface discoloration in the steaks from steers receiving HS. There was no difference in color uniformity detected in the GM. Both the LT and GM color analyses indicate benefits associated with administration of pre-mortem dietary His. Carnosine, anserine and L-His have been shown to have antioxidant properties (Boldyrev et al., 1988; Wade & Tucker, 1998). In fact, carnosine inhibits lipid oxidation (Decker & Faraji, 1990). Histidine can be metabolized within muscle tissue to form its dipeptides, carnosine and anserine. Although no previous research has reported the effects of providing rumen protected L-His or its dipeptides orally on color stability, several studies have demonstrated that treatment of fabricated meat products with carnosine affects color stability. Treating the exterior of ground beef with 1.0% carnosine inhibited brown color development and lipid peroxidation (Jun Lee, Hendricks, & Cornforth, 1999). Decreases in lipid peroxidation due to addition of carnosine helped to improve the overall flavor and appearance of beef products (Jun Lee et al., 1999). Further, treatment of beef patties with 50 mM carnosine increased a* value during a 20 d retail display and decreased both lipid and myoglobin oxidation (Sánchez-Escalante, Djenane, Torrescano, Beltrán, & Roncalés, 2001). Pigs supplemented with carnosine (100 mg/kg/d for 8 weeks) prior to slaughter found that the meat had an increased a* value following fabrication (Ma et al., 2010). Further, mRNA expression of superoxide dismutase and glutathione peroxidase was increased leading the authors to hypothesize that carnosine supplementation improves antioxidant capacity and meat quality of pigs (Ma et al., 2010). Additionally, previous studies have

outlined the differences between more and less color stable cuts of meats including some of the physiologic reasons believed to be responsible for these differences (Hood, 1980; Hunt & Hedrick, 1977; King, Shackelford, Rodriguez, & Wheeler, 2011; McKenna et al., 2005). In accordance with previous studies, the present study also observed a difference in color stability between steaks from the LT or the GM. However, the His supplement fed in this study appeared to alter color stability within the less color stable product to at least the same extent as the more color stable muscle, the LT. In the present study, we report that supplementing steers with 50 g/d of rumen protected histidine improved L*, a* and b* color values as well as decreased browning, discoloration and surface discoloration in both the LT and the GM, although the results were most apparent in the LT. 5. Conclusions Optimization of pre-harvest nutrition for feedlot cattle will allow producers to ensure that they are producing the highest quality meat at the lowest cost. Incorporation of available by-products, such as PBP, often times provide producers with another option in formulation of diets that may be more economically feasible. While Met and Lys are the first two limiting AAs, respectively, in feedlot diets, very little research has been conducted to determine the effects that supplemental His has on growth traits, carcass characteristics and end-product quality. We have demonstrated that there are no detrimental effects of incorporating 10% PBP into feedlot rations on growth or carcass traits and

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may actually result in a more tender end-product based on WBSF values. Further, steers finished on a CB ration may produce strip loin steaks that are more color stable based on numerical Hunter L*, a* and b* color values as well as AMSA meat color evaluation guidelines, however these differences may be too subtle for consumer detection. PB diets may also increase His, anserine and carnosine levels within the LT lending to an increased antioxidant capacity. We demonstrated that provision of 50 g/hd/d rumen protected His (Balchem) had no effect on growth or carcass traits but results in improvements in color stability in both the LT and GM muscles within the strip loin potentially expanding shelf life. The potential benefits of rumen protected His supplementation may be particularly relevant to the US export beef market since timing between harvest and market is extended, thus improved color stability may be even more advantageous. Potential benefits of His supplementation merit further examination pertaining to variations in dose, timing and beef quality outcomes. Acknowledgments The authors would like to thank the University of Idaho's Steer-AYear program for donation of the research steers utilized. We would also like to thank Performix for donation of the mineral supplement as well as Balchem Corporation for provision of the rumen protected histidine, both of which were provided to the steers throughout the finishing period. Additionally, we are very grateful to Washington Beef for harvesting the research animals and allowing for us to collect samples. Further, we extend appreciation to the University of Idaho meats lab staff for aiding us in collecting carcass grade information as well as processing and packaging of the retail cuts for analysis. Additionally, we acknowledge Dr. Pedram Rezamand at the University of Idaho for allowing us the use of his HPLC equipment. We would also like to thank Dr. Barrie Robison for his help with statistical analysis of the data. Lastly, we thank Eric Eldredge, Wade Sutton and Megan Venlos for their invaluable help in feeding and caring for the steers during the trial. References AMSA (1991). Guidelines for meat color evaluation. Proceedings 44th Reciprocal Meat Conference at Kansas State University, Manhattan, KS, 44. (pp. 1–17). Chicago, IL: National Live Stock and Meat Board. Aristoy, M.C., & Toldra, F. (1991). Deproteinization techniques for HPLC amino acid analysis in fresh pork muscle and dry-cured ham. Journal of Agricultural and Food Chemistry, 39, 1792–1795. Bidlingmeyer, B.A., Cohen, S.A., Tarvin, T.L., & Frost, B. (1987). A new, rapid, highsensitivity analysis of amino acids in food type samples. Journal — Association of Official Analytical Chemists, 70, 241. Boldyrev, A.A., Dupin, A.M., Pindel, E.V., & Severin, S.E. (1988). Antioxidative properties of histidine-containing dipeptides from skeletal muscles of vertebrates. Comparative Biochemistry and Physiology Part B: Comparative Biochemistry, 89, 245–250. Busboom, J.R., Nelson, M.L., Jeremiah, L.E., Duckett, S.K., Cronrath, J.D., Falen, L., & Kuber, P.S. (2000). Effects of graded levels of potato by-products in barley- and corn-based beef feedlot diets: II. Palatability. Journal of Animal Science, 78, 1837–1844. Chalupa, W., Chandler, J.E., & Brown, R.E. (1973). Abomasal infusion of mixtures of amino acids to growing cattle. Journal of Animal Science, 37, 339–340. Cornforth, D.P. (1994). Color — Its basis and importance. In A.M. Pearson, & T.R. Dutson (Eds.), Quality attributes and their measurement in meat, poultry and fish products, Vol. 9, Perseus Books Group. Daise, R.L., Zottola, E.A., & Epley, R.J. (1986). Potato-like odor of retail beef cuts associated with species of Pseudomonas. Journal of Food Protection, 49, 272–273. Decker, E.A., & Faraji, H. (1990). Inhibition of lipid oxidation by carnosine. Journal of the American Oil Chemists' Society, 67, 650–652. Dunnett, M., & Harris, R.C. (1999). Influence of oral ß-alanine and L-histidine supplementation on the carnosine content of the gluteus medius. Equine Veterinary Journal, 31 (S30), 499–504. Gatellier, P., Mercier, Y., Juin, H., & Renerre, M. (2005). Effect of finishing mode (pastureor mixed-diet) on lipid composition, colour stability and lipid oxidation in meat from Charolais cattle. Meat Science, 69, 175–186. Gorocica-Buenfil, M.A., Fluharty, F.L., Bohn, T., Schwartz, S.J., & Loerch, S.C. (2007). Effect of low vitamin A diets with high-moisture or dry corn on marbling and adipose tissue fatty acid composition of beef steers. Journal of Animal Science, 85, 3355–3366. Greenwood, R.H., & Titgemeyer, E.C. (2000). Limiting amino acids for growing Holstein steers limit-fed soybean hull-based diets. Journal of Animal Science, 78, 1997–2004.

Hanks, E.M., Heinemann, W.W., & Young, D.C. (1978). Potato process residue and bluegrass straw in steer finishing rations. Washington State University. College of Agriculture. Research Center. Bull, 871. Harris, R.C., Tallon, M.J., Dunnett, M., Boobis, L., Coakley, J., Kim, H.J., Fallowfield, J.L., Hill, C.A., Sale, C., & Wise, J.A. (2006). The absorption of orally supplied β-alanine and its effect on muscle carnosine synthesis in human vastus lateralis. Amino Acids, 30, 279–289. Heinemann, W. W., & Dyer, I. A. (1972). Nutritive value of patato slurry for steers. Washington Agric. Exp. Station Bull. 757. Pullman, WA. Hill, C.A., Harris, R.C., Kim, H.J., Harris, B.D., Sale, C., Boobis, L.H., Kim, C.K., & Wise, J.A. (2007). Influence of β-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity. Amino Acids, 32, 225–233. Hood, D.E. (1980). Factors affecting the rate of metmyoglobin accumulation in prepackaged beef. Meat Science, 4, 247–265. Huhtanen, P., Vanhatalo, A., & Varvikko, T. (2002). Effects of abomasal infusions of histidine, glucose, and leucine on milk production and plasma metabolites of dairy cows fed grass silage diets. Journal of Dairy Science, 85, 204–216. Hunt, M.C., & Hedrick, H.B. (1977). Chemical, physical and sensory characteristics of bovine muscle from four quality groups. Journal of Food Science, 42, 716–720. Jun Lee, B., Hendricks, D.G., & Cornforth, D. P. (1999). A comparison of carnosine and ascorbic acid on color and lipid stability in a ground beef Pattie model system. Meat Science, 51, 245–253. King, D.A., Shackelford, S.D., Rodriguez, A.B., & Wheeler, T.L. (2011). Effect of time of measurement on the relationship between metmyoglobin reducing activity and oxygen consumption to instrumental measures of beef longissimus color stability. Meat Science, 87, 26–32. Kruk, Z.A., Bottema, C.D.K., Davis, J.J., Siebert, B.D., Harper, G.S., Di, J., & Pitchford, W.S. (2008). Effects of vitamin A on growth performance and carcass quality in steers. Livestock Science, 119, 12–21. Little, A. C. (1975). A research Note Off on a tangent. Journal of Food Science, 40, 410–411. Ma, X.Y., Jiang, Z.Y., Lin, Y.C., Zheng, C.T., & Zhou, G.L. (2010). Dietary supplementation with carnosine improves antioxidant capacity and meat quality of finishing pigs. Journal of Animal Physiology and Animal Nutrition, 94, e286–e295. McCuistion, K.C., Titgemeyer, E.C., Awawdeh, M.S., & Gnad, D.P. (2004). Histidine utilization by growing steers is not negatively affected by increased supply of either ammonia or amino acids. Journal of Animal Science, 82, 759–769. McKenna, D.R., Mies, P.D., Baird, B.E., Pfeiffer, K.D., Ellebracht, J.W., & Savell, J.W. (2005). Biochemical and physical factors affecting discoloration characteristics of 19 bovine muscles. Meat Science, 70, 665–682. Muramoto, T., Nakanishi, N., Shibata, M., & Aikawa, K. (2003). Effect of dietary βcarotene supplementation on beef color stability during display of two muscles from Japanese Black steers. Meat Science, 63, 39–42. Nelson, M.L. (2010). Utilization and application of wet potato processing coproducts for finishing cattle. Journal of Animal Science, 88, E133–E142. Nelson, M.L., Busboom, J.R., Cronrath, J.D., Falen, L., & Blankenbaker, A. (2000). Effects of graded levels of potato by-products in barley- and corn-based beef feedlot diets: I. Feedlot performance, carcass traits, meat composition, and appearance. Journal of Animal Science, 78, 1829–1836. NRC (1996). Nutrient Requirements of Beef Cattle (7th rev. ed.). Washington, DC: National Academy Press. Patton, R. A., & Parys, C. (2012). Rumen-protected lysine, methionine, and histidine increase milk protein yield in dairy cows fed a metabolizable protein-deficient diet. Journal of Dairy Science, 95(10), 6042–6056. Radunz, A.E., Lardy, G.P., Bauer, M.L., Marchello, M.J., Loe, E.R., & Berg, P.T. (2003). Influence of steam-peeled potato-processing waste inclusion level in beef finishing diets: Effects on digestion, feedlot performance, and meat quality. Journal of Animal Science, 81, 2675–2685. Renerre, M. (1984). Variability between muscles and between animals of the color stability of beef meats. Sciences des Aliments, 4, 567–584. Rowe, L.J., Maddock, K.R., Lonergan, S.M., & Huff-Lonergan, E. (2004). Oxidative environments decrease tenderization of beef steaks through inactivation of μ-calpain. Journal of Animal Science, 82, 3254–3266. Sánchez-Escalante, A., Djenane, D., Torrescano, G., Beltrán, J.A., & Roncalés, P. (2001). The effects of ascorbic acid, taurine, carnosine and rosemary powder on colour and lipid stability of beef patties packaged in modified atmosphere. Meat Science, 58, 421–429. Sauter, E.A., Hinman, D.D., Bull, R.C., Howes, A.D., Parkinson, J.F., & Stanhope, D.L. (1980). Studies on the utilization of potato processing waste for cattle feed. Research bulletin — Agricultural experiment station. Stanhope, D.L., Hinman, D.D., Everson, D.O., & Bull, R.C. (1980). Digestibility of potato processing residue in beef cattle finishing diets. Journal of Animal Science, 51, 202. Storm, E., & Orskov, E.R. (1984). The nutritive value of rumen micro-organisms in ruminants. 4. The limiting amino acids of microbial protein in growing sheep determined by a new approach. The British Journal of Nutrition, 52, 613. Vanhatalo, A., Huhtanen, P., Toivonen, V., & Varvikko, T. (1999). Response of dairy cows fed grass silage diets to abomasal infusions of histidine alone or in combinations with methionine and lysine. Journal of Dairy Science, 82, 2674–2685. Wade, A.M., & Tucker, H.N. (1998). Antioxidant characteristics of L-histidine. The Journal of Nutritional Biochemistry, 9, 308–315. Wheeler, T.L., Koohmaraie, M., & Shackelford, S.D. (1996). Effect of vitamin C concentration and co-injection with calcium chloride on beef retail display color. Journal of Animal Science, 74, 1846–1853.