CHARACTERIZATION OF MARBLING DEPOSITION AND MANAGEMENT INFLUENCES ON BEEF TENDERNESS

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1007081
• Project Start Date: Nov 17, 2015
• Project End Date: Sep 30, 2020
• Program Code: [(N/A)]- (N/A)

Recipient Organization
SOUTH DAKOTA STATE UNIVERSITY
PO BOX 2275A
BROOKINGS,SD 57007

Performing Department
Animal Science

Non Technical Summary
The 2011 National Beef Quality Audit identified carcass inconsistency in quality grade as well as eating satisfaction, which is influenced by marbling and tenderness, as primary concerns for the beef industry. This benchmarking study estimated opportunity losses associated with decreased quality grade at $25.25 per animal, primarily attributed to inadequate marbling, resulting in a loss of $64 million annually in the beef industry. This project will investigate management influences on marbling deposition and beef tenderness. We will determine the effect of various management strategies and how to utilize these strategies to produce high quality beef and optimize production. To complete our aims, we will need to conduct experiments examining different diets and growth promotants used in the finishing phase of beef cattle production. These experiments will allow us to determine the best strategies for producing high quality beef that is acceptable in tenderness to consumers. Determining the strategies that produce high quality and tender beef will result in consumer satisfaction and increased demand for beef.

Animal Health Component

60%

Research Effort Categories

Basic

40%

Applied

60%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
308	3320	1030	50%
308	3320	1050	50%

Knowledge Area
308 - Improved Animal Products (Before Harvest);

Subject Of Investigation
3320 - Meat, beef cattle;

Field Of Science
1030 - Cellular biology; 1050 - Developmental biology;

Keywords

beef cattle

marbling

tenderness

management strategies

growth promotants

chromium

adipose tissue development

Goals / Objectives
Beef quality is important to ensure consumer acceptance of beef products. Beef quality is influenced by marbling as it is a primary determinant of USDA quality grade and carcass value. Also, marbling is important to beef palatability as marbling increases beef flavor and ensures a juicy eating experience in beef products. There is a need to produce more high quality beef to meet demands in the beef industry. Beef tenderness is still regarded as the most important palatability trait and thus variation in tenderness has been challenging for the beef industry to deal with as consumers demand tender beef. Improving beef tenderness through understanding the mechanisms controlling beef tenderness and how management strategies affect beef tenderness will allow the beef industry to produce a consistently tender product.The specific objectives of this research include:Determine mechanisms controlling marbling development in beef cattleDetermine if marbling in beef cattle can be enhanced through applied feeding strategiesDetermine if beef tenderness is affected by different management strategiesFuture Research:The first goal of this research is to study marbling development within beef cattle and understand the factors controlling beef tenderness. I would like to determine the cellular factors controlling marbling development so that we can design applied feeding strategies to enhance marbling deposition in beef cattle. This research would build upon the data we have generated highlighting the importance of PPAR Gamma in marbling development of beef cattle. Much of this research would be collaborative with ruminant nutritionists and other meat scientists at SDSU and potentially across the United States.Additionally, I would like to pursue a line of research examining beef tenderness with the goal of understanding how different management practices influence beef tenderness. This holds great value in the industry today as many different management practices are utilized and we need to understand their effect on beef tenderness. Some of this research is just beginning and other projects are in the development phase with other SDSU faculty. I plan to guide my research program so that I collaborate with ruminant nutritionists and beef cattle management scientists.

Project Methods
An experiment will be conducted with chromium supplementation in beef cattle diets and we will determine how supplemental chromium affects marbling deposition in beef cattle and beef tenderness. Feedlot steers will be provided a high energy feedlot diet with supplemental chromium (300 PPM chromium propionate, n=14)) or control high energy diet without the supplemental chromium (n=14). Steers will be weighed periodically to measure growth rate and harvested to collect carcass traits. Carcass traits including marbling score, 12th rib back fat thickness, longissimus muscle area, hot carcass weight, quality grade and yield grade will be evaluated for each carcass to determine the effect of supplemental chromium in the diet.Additionally, we will conduct experiments that investigate the influence of growth promoting technologies and varying management strategies on beef tenderness. Beef cattle will be subjected to differing management strategies including supplemental chromium (300 PPM chromium propionate) in the diet and growth promotants to determine the effect on tenderness of subsequent beef striploins through Warner-Bratzler shear force. Additional analysis will be conducted to determine how these different management strategies affect collagen content and solubility and proteolysis of beef strip loin steaks. This will allow us to better understand theinfluence of growth promoting technologies on beef tenderness and identify strategies to minimize the impact of any negative influence.Additional experiments will be conducted using diets designed to promote marbling development through targeting the cellular mechanisms controlling adipose tissue development supplementing long chain fatty acids at 2% of the diet. Steer calves (n = 96) used in this study will be selected from a larger pool (n = 200). All the calves will be obtained from two sources which provide very similar genetics and phenotypic uniformity. Standard arrival protocols and processing procedures will be followed, which includes vaccination and parasiticide protocol, body weight determination, and identification. The 96 steers will be allotted to pens of 8 head each, such that weight is similarly stratified within each pen. The pens will be placed on a moderate energy backgrounding program targeting an ADG of 2.8 lb/d. All steers will receive a Synovex-S implant during the backgrounding phase. Each pen will be randomly assigned to 1 of 2 treatments 1) control diet, 2) 2% supplementation of a commercially available rumen bypass fatty acids during the backgrounding and finishing phases to the control diet. The projected time on feed needed is 77 days for the backgrounding phase. Steers will then begin acclimation over 21 days to a high concentrate finishing diet. At day 28 of the finishing phase, all steers will receive a Revalor-S implant. All steers will be finished on a high-energy diet until a target harvest endpoint of 0.4 in. back fat is reached and then slaughtered through a commercial packing plant. Carcasses will be evaluated for ribeye area, external fat thickness, marbling score, hot carcass weight, and kidney, pelvic and heart fat following a 24 hr chilling process. Carcass composition will also be determined using 9-10-11 rib dissections according to Hankins and Howe (1946).Carcass Evaluation:Steers will be harvested at a commercial packing facility. Following carcass chilling (approximately 24 hours), hot carcass weight (HCW), REA, 12th rib backfat, and estimated percentage of kidney, pelvic and heart fat (KPH), will be recorded for each individual carcass and used to calculate yield grade according to USDA guidelines. USDA marbling score and carcass maturity will be used to determine quality grade of each carcass.Tenderness Evaluation:Steaks designated for Warner Bratzler shear force determination will be thawed 24 hours at 4°C and then cooked on an electric clam shell grill (George Forman Indoor/Outdoor Grill, Model GGR62, Lake Forest, IL) to 71ºC. Peak internal cooked temperature measurements will be recorded for each steak using a hand held thermometer (Model 39658-K, Atkins Technical, Gainsville, FL). Cooked steaks will be cooled for 24 hours at 4°C before removing 6 to 8 cores (1.27 cm in diameter) parallel to the muscle fiber orientation (AMSA, 1995). A single, peak shear force measurement will be obtained for each core using a Warner-Bratzler shear machine (G-R Electric Manufacturing Company, Manhattan, KS). Measurements of the peak shear force will be recorded and averaged to obtain a single shear force value for each steak.Collagen Analysis:Samples will be powdered in liquid nitrogen using a commercial blender. Two g of powdered sample were weighed into tubes with the addition of 12 mL of 0.25 strength Ringer's solution (Hill, 1966). Samples will be heated at 77ºC for 60 min in a shaking water bath and centrifuged at 10,840 x g for 5 min. Supernatant will be decanted into a flat bottom flask while 8 mL of 0.25 strength Ringer's solution was added to the precipitate, vortexed, and centrifuged again at 10,840 x g for 5 min. Supernatant will be added to previously decanted supernatant and each flask of supernatant and precipitate will then be digested for 16 h in 6 N HCl, transferred into new beakers and pH adjusted to 6.2 using 12 M NaOH. To remove any interfering color,approximately 0.5 g of charcoal will be added to a 250 mL volumetric flask where solutions will be diluted to 250 mL. Hydroxyproline content for both soluble and insoluble fractions will be determined in duplicate using spectrophotometric methods according to Bergman and Loxley (1963). One mL of sample was combined with 2 mL isopropanol and 1 mL of oxidant solution. After incubating for 4 min, 13 mL of Ehrlichs reagent will be added to the solution and vortexed. Reactions were incubated in a water bath at 60ºC for 25 min and allowed to cool before reading the absorbance at 558 nm using a spectrophotometer. Using values of known standards, sample hydroxyproline concentrations will be determined. Collagen content is calculated by multiplying the hydroxyproline concentration of both soluble and insoluble fractions by 7.25 (Goll et al., 1963).Proteolysis Analysis:Steaks from each treatment will be analyzed for Troponin-T degradation, a hallmark of postmortem proteolysis (Koohmarie, 1994; Mohrhauser et al., 2011). Each sample will be analyzed through SDS-PAGE and subsequent immunoblotting. The amount of intact Troponin-T will be measured for disappearance to determine differences in postmortem proteolysis among treatments.The efforts that will be used to disseminate project results have previously been described under "audience".Success of the project will be evaluated by publication and presentation of results that demonstrate 1) the ability of different management strategies to influence marbling development 2) the effect of different management strategies on beef tenderness and 3) how different management strategies influence collagen content, solubility, and postmortem proteolysis of beef steaks.

Progress 11/17/15 to 09/30/20

Outputs
Target Audience:Meat Industry Professionals - This audience was targeted because they will apply this research to the products they produce and market. Meat industry professionals were targeted through formal and informal classroom activities (many undergraduate and graduate students will choose the meat industry as their career), Extension/outreach activities, and scientific meetings. Data and results from this research were utilized in the Meat Animal Growth and Development course (AS 750) I instruct, where students learn about muscle growth, adipose tissue deposition, and meat quality. Research Community - We are targeting animal and meat scientists. The knowledge gained through our research efforts will advance the scientific understanding in our field and help other research programs. We targeted these individuals through peer-reviewed publications and presentations at the annual meeting of the American Meat Science Association which was held in conjunction with the International Congress of Meat Science and Technology. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Three graduate students and two undergraduate students were trained in this project during the last year. Christina Fehrman, PhD Student, Animal Science, entire reporting period, 49% graduate research assistantship. Learned skills in tenderness assessment, meat quality analysis, and data analysis. Presented at the joint 73rdnd Annual Reciprocal Meats Conference and International Congress of Meat Science and Technology (Virtual Conference, Amer. Meat Sci. Assoc.). Graduated August 2020. Austin Egolf, MS Student, Animal Science, entire reporting period, 49% graduate research assistantship. Learned skills in tenderness assessment, meat quality analysis, and data analysis. Graduated August 2020. Trevor DeHaan, MS Student, Animal Science, entire reporting period, 49% graduate research assistantship. Learned skills in tenderness assessment, meat quality analysis, and data analysis. In progress August 2019-present. Luis Gonzales-Tovar, Undergraduate Researcher, Animal Science, December 2019 - May 2020. Learned skills in data collection, meat cookery and smoking, jerky processing, and data analysis. Daniela Ortega-Gutierrez, Undergraduate Researcher, Animal Science, December 2019 - May 2020. Learned skills in data collection, meat processing, cookery, and data analysis. How have the results been disseminated to communities of interest?Animal and Meat Scientists: We published two peer reviewed journal articles in Translational Animal Science and published 5 abstracts during the reporting period at the Midwest Animal Science Meetings and the International Congress of Meat Science and Technology/Reciprocal Meat Conference. Results, when appropriate, have been used in the graduate level Animal Growth and Development course (AS 750), Advanced Meat Science course (AS 541), and Introduction to Meat Science course (AS 241) at SDSU. This information has also been included in the annual SDSU Beef 2020 short course where applicable to disseminate to producers and presented at the annual SDSU Beef Day Program hosted through SDSU Extension. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Objective 1: Determine mechanisms controlling marbling development in beef cattle (100% Accomplished) We conducted an experiment where we utilized chromium supplementation at 400 ppb in feedlot cattle diets and examined the effects on growth, marbling development, and meat quality. Our data from this experiment showed chromium supplementation at 400 ppb in feedlot cattle diets can increase dressing percentage (2%, 6 pounds) but decreased marbling deposition by 10% through one of the major adipose tissue growth and development signaling factors. This is novel data and information in the meat science literature. The second experiment investigated the effects of feeding ruminal bypass long chain fatty acids to activate adipose tissue growth and development factors in beef cattle diets. This experiment supplemented rumen bypass long chain fatty acids (Megalac-R, 25.6% C16:0, 3.5% C18:0, 32.9% C18:1C, 31.8% C18:2) at 2% of the diet dry matter. This experiment showed that showed ruminal bypass long chain fatty acid supplementation was not effective at improving marbling. However, supplementing 2% of diet as rumen bypass long chain fatty acids increased average daily gain by 3% (P < 0.05), gain to ratio by 3.5% (P < 0.05), and hot carcass weight of cattle by 12 lbs (P < 0.05) Objective 2: Determine if marbling in beef cattle can be enhanced through applied feeding strategies (100% Accomplished) We conducted 3 experiments to determine in marbling in beef cattle can enhanced through applied feeding strategies that could be utilized in South Dakota and the upper Midwest region of the US. The first experiment utilized chromium supplementation at 400 ppb in feedlot cattle diets. This experiment showed that chromium supplementation at 400 ppb in feedlot cattle diets negatively impacted marbling by 10%. The second experiment utilized ruminal bypass long chain fatty acids (Megalac-R, 25.6% C16:0, 3.5% C18:0, 32.9% C18:1C, 31.8% C18:2) to activate adipose tissue growth and development factors in beef cattle diets. This experiment showed that ruminal bypass long chain fatty acid supplementation at 2% of the diet dry matter was not effective at improving marbling. However, ruminal bypass long chain fatty acid supplementation at 2% of the diet dry matter did increase body weight gain by 22 lbs (P = 0.01) and total body adipose tissue by 1.6% (P < 0.05), showing this may be a strategy to increase fat development in cattle with less genetic ability to develop and grow fat. The third experiment examined feeding a Brassica mixture of cover crops on beef carcass and meat quality. This experiment showed that feeding a diet composed of freshly cut Brassica mixture of cover crop forage (CC) containing radish, turnip, rapeseed, rye grass, and a liquid supplement phase for 44 days had no impact on marbling or adipose tissue development. This is a positive result, showing a Brassica mixture of cover crops can utilized in early feedlot cattle diets and have no negative impacts on marbling or fat development. The results from these 3 experiments provide new data and information for cattle producers and animal scientists showing that marbling is a difficult trait to enhance in beef cattle via feeding strategy. This data also provides information on long chain fatty acid supplementation and Brassica mixture of cover crops fed to cattle will not negatively impact marbling in beef carcasses. Objective 3: Determine if beef tenderness is affected by different management strategies (100% Accomplished) We conducted 3 experiments to determine if beef tenderness can be affected by different management strategies utilized in beef production systems. The first experiment applied growth promotants, including ionophores, beta agonists, and hormone implants, to beef cattle during the last feeding phase. Meat quality analysis of beef from these cattle was conducted and data showed that steaks from cattle with hormone implants and beta agonists had increased shear force values of 1 lb and 1.2 lbs, respectively (P < 0.0001). Consumers preferred steaks from beef cattle raised using less growth promoting technology (P < 0.05) compared with steaks from beef cattle grown utilizing no antibiotics, beta agonists, and hormone implants. The second experiment was conducted on feeding a Brassica mixture of cover crops on beef carcass and meat quality. This experiment showed that feeding Brassica mixture of cover crops during the early feeding phase resulted in more tender steaks at 3 days (6.4 vs 7.5 lbs of shear force, P < 0.05) and 7 days (5.5 vs 7.5 lbs of shear force, P < 0.05) after slaughter. Further research is warranted to determine the mechanism influencing tenderness when feeding Brassica mixture of cover crops. The third experiment sought to determine if increased hot carcass weights in the beef industry influenced beef tenderness and quality due to variation in chilling rates. Much of this increase in weight is attributed to better genetics, increased use of growth promoting technologies, and better management strategies to increase beef production. Therefore, to determine if increased hot carcass weights influence beef tenderness we selected carcasses from the USDA Choice and USDA Select quality grades that range from 650-750 lbs, 850-950 lbs, and 1025-1150 lbs. We tracked these carcasses through the chilling process and collected eye of round, strip loins, and Serratus Ventralis cuts to examine the effect of carcass weight and chilling on beef tenderness. This experiment showed steaks aged 10 or 14 days were more tender than steaks aged for 5 days (P < 0.05), and all differences among weight class and quality grade disappeared by d 14 after slaughter. Similarly, consumer sensory data indicated light weight strip loin steaks aged 5 days were consistently among the toughest steaks (P < 0.05) from the USDA Choice and Select quality grades. Overall, these experiments showed that numerous management factors impact beef tenderness. This will allow cattle producers and meat packers to determine the best options for them to provide high quality beef to their consumers.

Publications

• Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Webb, M. J., J. J. Block, A. A. Harty, R. R. Salverson, R. F. Daly, J. R. Jaeger, K. R. Underwood, R. N. Funston, D. P. Pendell, C. A. Rotz, K. C. Olson, A. D. Blair. 2020. Cattle and carcass performance, and life cycle assessment of production systems utilizing additive combinations of growth promotant technologies. Translational Animal Science. txaa216, 4(4)1-15. https://doi.org/10.1093/tas/txaa216
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Fehrman, C., K. Underwood, J.K. Grubbs, J. Walker, C. Wright, K. Olson, W. Rushce, A. Blair. 2020. South Dakota State University Beef 2020 increases participant knowledge of the beef industry. Translational Animal Science. 4(3)1-7. https://doi.org/10.1093/tas/txaa161
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Hite, L.M., C.E. Bakker, T.C. DeHaan, A.D. Blair, K.R. Underwood, J.K. Grubbs. 2020. Influence of carcass chilling system on chuck, loin, and round temperature decline. 2020 International Congress of Meat Science and Technology and Reciprocal Meat Conference. August 2-7. Virtual Conference.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Bakker, C.E., L.M. Hite, A.D. Blair, J.K. Grubbs, C.L. Wright, D.W. Brake, A.J. Smart, K.R. Underwood. 2020. Influence of feeding a cover crop mixture including brassicas during backgrounding on carcass characteristics and beef tenderness. 2020 International Congress of Meat Science and Technology and Reciprocal Meat Conference. August 2-7. Virtual Conference.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Gubbels. E., R.R. Salverson, C.L. Wright, K.M. Cammack, J.F. Legako, Z.K. Smith, J.K. Grubbs, K.R. Underwood. K.C. Olson, A.D. Blair. 2020. Comparison of winter cow feeding strategies on offspring carcass characteristics and meat quality. 2020 International Congress of Meat Science and Technology and Reciprocal Meat Conference. August 2-7. Virtual Conference.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Egolf. S.R., A. Egolf, H.R. Rode, L.M. Hite, C.E. Bakker, A.D. Blair, K.R. Underwood, J.K. Grubbs. 2020. Increased internal temperature in heavy beef carcasses influences product quality. 2020 International Congress of Meat Science and Technology and Reciprocal Meat Conference. August 2-7. Virtual Conference.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Egolf. S.R., J.K. Jassen, R. Cox, A. Egolf, H.R. Rode, L.M. Hite, C.E. Bakker, A.D. Blair, J.K. Grubbs, K.R. Underwood. 2020. Heavier beef hot carcass weights impact sensory traits. 2020 International Congress of Meat Science and Technology and Reciprocal Meat Conference. August 2-7. Virtual Conference.
• Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Egolf, S.R., L.M. Hite, A.C. Egolf, C.E. Bakker, A.D. Blair, J.K. Grubbs, K.R. Underwood. 2020. Carcass weight and quality grade impact the rate of internal temperature decline in beef primals. 2020. Midwest Section - American Society of Animal Science. March 2-4. Omaha, NE.

Progress 10/01/18 to 09/30/19

Outputs
Target Audience:Meat Industry Professionals - This audience was targeted because they will apply this research to the products they produce and market. Meat industry professionals were targeted through formal and informal classroom activities (many undergraduate and graduate students will choose the meat industry as their career), Extension/outreach activities, and scientific meetings. Data and results from this research were utilized in the Meat Animal Growth and Development course AS 750) I instruct, where students learn about muscle growth, adipose tissue deposition, and meat quality. Research Community - We are targeting animal and meat scientists. The knowledge gained through our research efforts will advance the scientific understanding in our field and help other research programs. We targeted these individuals through peer-reviewed publications and presentations at the annual meeting of the American Meat Science Association. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Two graduate students and two undergraduate students were trained in this project. Christina Fehrman, PhD Student, Animal Science, entire reporting period. 49% graduate research assistantship. Learned skills in tenderness assessment, meat quality analysis, and data analysis. Presented at the 72nd Annual Reciprocal Meats Conference (Ft. Collins, CO, Amer. Meat Sci. Assoc.). Austin Egolf, MS Student, Animal Science, entire reporting period. 49% graduate research assistantship. Learned skills in tenderness assessment, meat quality analysis, and data analysis. Allison Howell, Undergraduate Researcher, Animal Science, May 2019 - August 2019. Learned skills in data collection, beef quality analysis, tenderness assessment, data analysis, and participated in extension and outreach events. Presented at the undergraduate research day at SDSU (Brookings, SD, SDSU). Maria Velazco Fasce, Undergraduate Researcher, Animal Science, January 2019 - May 2019. Learned skills in data collection, meat processing, cookery, and data analysis. How have the results been disseminated to communities of interest?Animal and Meat Scientists: We have published one article in the Meat Science Journal, one article in Translational Animal Science, submitted one article to the Journal of Extension, and published 3 abstracts during the reporting period. Results when appropriate have been used in courses and short-courses hosted by SDSU. What do you plan to do during the next reporting period to accomplish the goals?Goal 1. Determine mechanisms controlling marbling development in beef cattle: Submit findings on the influence of chromium supplementation on insulin signaling and marbling development for publication. Goal 2. Determine if marbling in beef cattle can be enhanced through applied feeding strategies: Analyze data and submit findings on feeding cover crops during backgrounding to beef cattle. 3. Determine if beef tenderness is affected by different management strategies Analyze data and submit findings for peer review on: 1) feeding cover crops during backgrounding to beef cattle, and 2) research focused on the influence of varying carcass weights on beef tenderness. Submit findings on increased beef carcass weights, chilling rates, and tenderness for peer review.

Impacts
What was accomplished under these goals? Objective 1: Determine mechanisms controlling marbling development in beef cattle (90% Accomplished) We are currently drafting a manuscript on the effects of chromium supplementation on beef cattle performance and will submit for publication in early 2020. Our data supports that chromium supplementation at 400 ppb in the diet can increase dressing percentage (2 percent, 6 pounds) but decrease marbling deposition by 10% through one of the major adipose tissue development signaling factors. Objective 2: Determine if marbling in beef cattle can be enhanced through applied feeding strategies (85% Accomplished) We have published our finding focused on the supplementation of ruminal bypass long chain fatty acids on cattle growth and subsequent beef quality in the Translational Animal Science Journal. Our study showed ruminal bypass long chain fatty acid supplementation was not effective in improving marbling. We have completed the live animal portion of the research focused on feeding a Brassica mixture of cover crops on beef carcass and meat quality. These cattle were harvested in June of 2019 and carcass and meat quality data are being analyzed. We intend to submit these findings for peer review publication by August of 2020. Objective 3: Determine if beef tenderness is affected by different management strategies (80% Accomplished) We conducted research on feeding a Brassica mixture of cover crops on beef carcass and meat quality. These cattle were harvested in June of 2019 and carcass and meat quality data is being analyzed. We are currently conducting tenderness and sensory analysis on steaks from these cattle. We intend to submit these findings for peer review publication by August of 2020. We conducted a research project to determine if increased hot carcass weights in the beef industry influenced beef tenderness and quality due to variation in chilling rates. Much of this increase in weight is attributed to better genetics, increased use of growth promoting technologies, and better management strategies to increase beef production. Therefore, to determine if increased hot carcass weights influence beef tenderness we selected carcasses from the USDA Choice and Select quality grades that range from 650-750 lbs, 850-950 lbs, and 1025-1150 lbs. We tracked these carcasses through the chilling process and collected eye of round, strip loins, and Serratus Ventralis cuts to examine the effect of carcass weight and chilling on beef tenderness. This project was completed in May of 2019. Steaks aged 10 or 14 days were more tender (P < 0.05) than steaks aged for 5 days, and all differences among weight class and quality grade disappeared by d 14. Similarly, consumer sensory data indicated light weight steaks aged 5 days were consistently among the toughest steaks (P < 0.05) from the USDA Choice and Select quality grades. We are currently drafting 2 publications from this data to be submitted for peer review by July of 2020.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Webb, M.J., J.J. Kincheloe, R.N. Funston, K.R. Underwood, J.F. Legako, A.A. Harty, R.R. Salverson, K.C. Olson, A.D. Blair. 2019. Influence of maternal protein restriction in primiparous heifers during mid- and/or late-gestation on meat quality and fatty acid profile of progeny. Meat Science. 152:32-37. https://doi.org/10.1016/j.meatsci.2019.02.006
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Bakker, C.E., A.D. Blair, J.K. Grubbs, A.R. Taylor, D.W. Brake, N.M. Long, J.K. Grubbs, K.R. Underwood. 2019. Effects of rumen protected long chain fatty acid supplementation during the finishing phase of beef steers on carcass characteristics, meat quality, and fatty acid profiles. Translational Animal Science. 3(4). doi: 10.1093/tas/txz136
• Type: Journal Articles Status: Submitted Year Published: 2019 Citation: Fehrman, C., K. Underwood, J.K. Grubbs, J. Walker, C. Wright, K. Olson, W. Rushce, A. Blair. 2019. South Dakota State University Beef 2020 increases participant knowledge of the beef industry. Journal of Extension.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Fehrman, C.E., J.K. Grubbs, K.R. Underwood, A.D. Blair. 2019. Impact of two levels of low voltage electrical stimulation on beef quality. 72nd Reciprocal Meats Conference. June 23-26. Ft. Collins, CO.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Hite, L.M., J.K. Grubbs, A.D. Blair, K.R. Underwood. 2019. Influence of post-harvest circulatory rinse on tenderness of cow striploin steaks. 72nd Reciprocal Meats Conference. June 23-26. Ft. Collins, CO.
• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Gubbels, E.R., R.R. Salverson, K.M. Cammack, J.K. Grubbs, K.R. Underwood, K.C. Olson, A.D. Blair. 2019. Effects of low-stress weaning on calf health, growth performance, and carcass characteristics. 72nd Reciprocal Meats Conference. June 23-26. Ft. Collins, CO.

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:Meat Industry Professionals - This audience was targeted because they will apply this research to the products they produce and market. Meat industry professionals were targeted through formal and informal classroom activities (many undergraduate and graduate students will choose the meat industry as their career), Extension/outreach activities, and scientific meetings. Data and results from this research were utitilized in the Meat Animal Growth and Development course I instruct, where students learn about muscle growth, adipose tissue deposition, and meat quality. Research Community - We are targeting animal and meat scientists. The knowledge gained through our research efforts will advance the scientific understanding in our field and help other research programs. We targeted these individuals through peer-reviewed publications and presentations at the annual meeting of the American Meat Science Association. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Two graduate students and one undergraduate student were trained in this project. Christina Fehrman, PhD Student, entire reporting period. 49% graduate research assistantship. Learned skills in tenderness assessment, meat quality analysis, and data analysis. Presented at the 71st Annual Reciprocal Meats Conference (Kansas City, MS, Amer. Meat Sci. Assoc.). Austin Egolf, MS Student, June 2018 - September 2018. 49% graduate research assistantship. Learned skills in data collection and meat quality analysis. Kyle Leveau, Undergraduate Researcher, January 2018 - May 2018. Learned skills in data collection, beef quality analysis, and data analysis. How have the results been disseminated to communities of interest?Animal and Meat Scientists: We have published one article in the Journal of Animal Science, submitted a manuscript to the Meat Science Journal, and 2 abstracts during the reporting period. Results when appropriate have been used in courses and short-courses hosted by SDSU. What do you plan to do during the next reporting period to accomplish the goals?Goal 1. Determine mechanisms controlling marbling development in beef cattle: Submit findings on insulin signaling and marbling development for publication. Goal 2. Determine if marbling in beef cattle can be enhanced through applied feeding strategies: Submit findings on long chain fatty acid supplementation and marbling development for publication. Conduct research on feeding cover crops during backgrounding to beef cattle and collect growth, carcass, and meat quality data. 3. Determine if beef tenderness is affected by different management strategies Publish findings of beef tenderness from cattle raised with varying levels of technology. Conduct research on feeding cover crops during backgrounding to beef cattle and research focused on the influence of varying carcass weights on beef tenderness.

Impacts
What was accomplished under these goals? Objective 1: Determine mechanisms controlling marbling development in beef cattle (75% Accomplished) We have analyzed the data focusing on chromium supplementation and started preparing this data for publication. Our data supports that chromium supplementation at 400 ppb in the diet can increase dressing percentage (2 percent, 6 pounds) but decrease marbling deposition by 10% through one of the major adipose tissue development signaling factors. We are currently preparing the manuscript and will allow the co-authors to review and will submit this data for publication in 2019. Objective 2: Determine if marbling in beef cattle can be enhanced through applied feeding strategies (75% Accomplished) We have prepared a manuscript focused on the supplementation of ruminal bypass long chain fatty acids on cattle growth and subsequent beef quality. We will submit these findings for publication in early 2019. Our study showed ruminal bypass long chain fatty acid supplementation was not effective in improving marbling. We started conducting research on feeding a Brassica mixture of cover crops on beef carcass and meat quality. These cattle are currently being fed the Brassica cover crop during the backgrounding phase and will transition to a finishing diet in December 2018. We are collecting data on intakes, feeding behavior, and growth during this phase of the research. These animals are anticipated to go to harvest in May 2019. Objective 3: Determine if beef tenderness is affected by different management strategies (60% Accomplished) We started conducting research on feeding Brassica mixture of cover crops on beef carcass and meat quality. These cattle are currently being fed the Brassica cover crop during the backgrounding phase and will transition to a finishing diet in December 2018. We are collecting data on intakes, feeding behavior and growth during this phase of the research. These animals are anticipated to go to harvest in May 2019 to determine effects the diet has on beef tenderness. We are also conducting a research project to determine if increased hot carcass weights in the beef industry have influenced beef tenderness and quality due to variation in chilling rates. Much of this increase is weight is attributed to better genetics, increased use of growth promoting technologies, and better management strategies to increase beef production. Therefore, to determine if increased hot carcass weights influence beef tenderness we selected carcasses from the USDA Choice and Select quality grades that range from 650-750 lbs, 850-950 lbs, and 1025-1150 lbs. We tracked these carcasses through the chilling process and collected eye of round, strip loins, and Serratus Ventralis cuts to examine the effect of carcass weight and chilling on beef tenderness. This project is ongoing and expected to be completed in May of 2019.

Publications

• Type: Journal Articles Status: Submitted Year Published: 2018 Citation: Webb, M. J., Kincheloe, J. J., Funston, R. N., Underwood, K. R., Legako, J. F., Harty, A. A., Salverson, R. R., Olson, K. C., Blair, A. D. Influence of maternal protein restriction in primiparous heifers during mid- and/or late-gestation on meat quality and fatty acid profile of progeny. Meat Science. (submitted)
• Type: Journal Articles Status: Published Year Published: 2017 Citation: Webb, M. J., Harty, A. A., Salverson, R. R., Kincheloe, J. J., Scramlin-Zuelly, S. M., Underwood, K. R., Luebbe, M. K., Olson, K. C., Blair, A. D. (2017). Effect of nursing-calf implant timing on growth performance and carcass characteristics. Journal of Animal Science. Dec;95(12):5388-5396. doi: 10.2527/jas2017.1633
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Fehrman, C. E., Underwood, K. R., Walker, J. A., Wright, C. L., Gonda, M. G., Nold, R. A., Olson, K. C., Rhody, A., Rusche, W. C., Blair, A. D. 2018. SDSU Beef 2020 increases beef industry knowledge for participants. American Meat Science Association Reciprocal Meats Conference, June, 25-27, Kansas City, MO.

Progress 10/01/16 to 09/30/17

Outputs
Target Audience:Meat Industry Professionals - This audience was targeted because meat industry professionals will apply this research to products they market. Meat industry professionals were targeted through formal and informal classroom activities (many undergraduate and graduate students will choose the meat industry as their career), Extension/outreach activites, and scientific meetings. Research Community - We are specifically targeting animal and meat scientists. The knowledge gained through our research efforts will advance the scientific understanding in our field and help other research programs. We targeted these individuals through peer-reviewed publications and presentations at scientific meetings. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Two graduate students were trained in this project. Christina Fehrman, PhD Student, entire reporting period. 49% graduate research assistantship. Learned skills in tenderness assessment, meat quality analysis, proximate analysis, and data analysis. Presented research at the 70 Reciprocal Meats Conference and wrote final report for project. Jason Griffin, MS Student, entire reporting period. Learned skills in tenderness assessment, meat quality analysis, carcass composition, and real-time RT-PCR. In progress of completing thesis and preparing data for publication. How have the results been disseminated to communities of interest?Animal and Meat Scientists: We have published 4 abstracts during this reporting period. Two PhD student have presented to meat scientists and meat industry professionals in a poster format at the 70th Reciprocal Meats Conference (College Station, TX, Amer. Meat Sci. Assoc.) and Midwest American Society of Animal Science Meeting. Stakeholders: We have published one popular press article in Meatingplace updates and one final report to the South Dakota Beef Industry Council that will be shared with all the groups that comprise the Beef Council. What do you plan to do during the next reporting period to accomplish the goals?Goal 1: Determine mechanisms controlling marbling development in beef cattle: Publish findings on insulin signaling and marbling development in 2018. Goal 2: Determine if marbling in beef cattle can be enhanced through applied feeding strategies: Submit findings on chromium supplementation and long chain fatty supplementation on marbling in beef cattle in 2018. Begin research utilizing cover crops during backgrounding on beef carcass quality and marbling. Goal 3: Determine if beef tenderness is affected by different management strategies: Publish findings on meat quality analysis from cattle raised with varying levels of technology. Begin research utilizing cover crops during backgrounding on beef tenderness.

Impacts
What was accomplished under these goals? Goal 1: Determine mechanisms controlling marbling development in beef cattle (60% complete). We conducted an experiment focusing on chromium supplementation and insulin signaling in 2016-2017. We showed that chromium supplementation, which increases insulin sigaling in beef cattle, will decrease (P < 0.05) peroxisome proliferator activated receptor gamma (PPAR) protein expression in feedlot steers. The decrease in PPAR expression was associated with decreased (P < 0.05) marbling scores in feedlot steers supplemented chromium. We anticipate to submit this data for publication in early 2018. Goal 2: Determine if marbling in beef cattle can be enhanced through applied feeding strategies (65% complete). We conducted research to determine whether chromium supplementation and ruminal bypass long chain fatty acid supplementation can influence marbling deposition in beef cattle. Chromium supplementation in calf fed feedlot steers decreased (P < 0.05) marbling scores in carcasses compared to cattle not supplemented chromium. Long chain fatty acid supplementation during the backgrounding and finishing phase did not alter (P > 0.05) marbling score but did increase (P < 0.05) total carcass fat in feedlot steers. We anticipate to submit this data for publication in 2018. We will be conducting an experiment examining the effects cover crops during backgrounding on beef carcass quality. Goal 3: Determine if beef tenderness is affected by different management strategies (40% complete). Cattle have been fed using varying levels of growth promoting technologies including implants, inophores and beta agonists to determine the effect of these technologies on beef tenderness. Meat quality analysis was conducted on the meat products from these animals and it showed that increased level of growth promoting technologies decreased tenderness (P < 0.05) and consumers preferred (P < 0.05) steaks from animal raised with less technology. We hope to publish this data in 2018. We will be conducting an experiment examining the effects cover crops during backgrounding on beef tenderness.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Webb, M. J., Pendell, D. L., Harty, A. A., Salverson, R. R., Rotz, C. A., Underwood, K. R., Olson, K. C., Blair, A. D. 2017. Influence of growth promoting technologies on animal performance, production economics, environmental impacts and carcass characteristics of beef. Proc. Rec. Meats Con. (Abstr. #22) College Station, TX, June 17-21, 2017. Amer. Meat Sci. Ass.
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Webb, M. J., D. L. Pendell, A. A. Harty, R. R. Salverson, C. A. Rotz, K. R. Underwood, K. C. Olson, and A. D. Blair. 2017. Identifying consumer preference for beef raised with different production systems. Proc. Rec. Meats Con. (Abstr. #90) College Station, TX, June 17-21, 2017. Amer. Meat Sci. Ass.
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Webb, M. J., J. J. Kincheloe, R. Funston, K. R. Underwood, M. G. Gonda, K. C. Olson, and A. D. Blair. 2017. Impact of maternal MP restriction on progeny carcass characteristics, meat quality and fatty acid profile. J. Anim. Sci. Vol. 95 (Supp 2): 46. Proc. Midwest. Sec. Amer. Soc. Anim. Sci., Omaha, NE, March 15-17.
• Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Fehrman, C. E., Rode, H. R., Grubbs, J. K., Blair, A. D., Underwood, and K. R. 2017. Rumen protected long chain fatty acid supplementation effects on beef carcass traits and composition. Proc. Rec. Meats Con. (Abstr. #4) College Station, TX, June 17-21, 2017. Amer. Meat Sci. Ass.

Progress 11/17/15 to 09/30/16

Outputs
Target Audience:Meat Industry Professionals - This audience was targeted because meat industry professionals will apply this research to products they market. Meat industry professionals were targeted through formal and informal classroom activities (many undergradaute and graduate students will choose the meat industry as their career), Extension/outreach activites, and scietific meetings. Research Community - We are specifically targeting animal and meat scientists. The knowledge gained through our research efforts will advance the scientific understanding in our field and help other research programs. We targeted these individuals through peer-reviewed publications and presentations at scientific meetings. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Five graduate students and 2 undergraduate students were trained in this project. Christina Fehrman, PhD Student, August 2016 - Present. 49% graduate research assistantship. Learned skills in tenderness assessment, meat quality analysis, and carcass composition. Megan Taylor, MS Student, August 2016 - Present. 49% graduate research assistantship. Learned skills in tenderness assessment, meat quality analysis, and shelf life. Heather Rode, MS Student, entire reporting period. 49% graduate research assistantship. Learned skills in cattle management, meat quality analysis, and carcass composition, Western blotting,real-time RT-PCR analysis. Presented an abstract at the Reciprocal Meats Confenrece in July 2016. Jason Griffin, MS Student, entire reporting period. Learned skills in tenderness assessment, meat quality analysis, carcass composition, and real-time RT-PCR. Wrote final report for project. Darcy Burton, MS Student, 10/1/2015 - 8/1/2016. Learned skills in tenderness assessment, meat color analysis, texture analysis, sensory traits, and Western blotting. Presented and defended MS thesis. Cheyenne Edmundson, BS Student, 10/1/2015 - 5/5/2016. Learned skills in meat quality and carcass composition analysis. Janet VandeStroet, BS Student, 1/10/2016 - 8/31/2016. Learned skills in meat tenderness and carcass composition analysis. How have the results been disseminated to communities of interest?Animal and Meat Scientists: We have published 3 peer-reviewed manuscripts and two abstracts during this reporting period. A MS and PhD student have presented to meat scientists and meat industry professionals in a poster format (69th Reciprocal Meats Conference, San Angelo, TX, Amer. Meat Sci. Assoc.) Stakeholders: We have published one popular press article in Meatingplace updates. What do you plan to do during the next reporting period to accomplish the goals?Goal 1: Determine mechanisms controlling marbling development in beef cattle: Complete analysis and submit findings on insulin signaling and marbling development in 2017. Goal 2: Determine if marbling in beef cattle can be enhanced through applied feeding strategies Complete research on chromium supplementation and publish finding in 2017. Use this data as preliminary data for a larger proposal. Complete ruminal bypass long chain fatty acid supplementation project and present data at a scientific meeting in 2017. Goal 3: Determine if beef tenderness is affected by different management strategies Complete meat quality analysis on cattle raised with varying levels of technology and present data at a scientific meeting. Pursue research focusing on differing growth rates in cattle and their relationship to beef tenderness.

Impacts
What was accomplished under these goals? Goal 1: Determine mechanisms controlling marbling development in beef cattle (35% complete). We have conducted experiments examining the relationship of Peroxisome proliferator activated receptor gamma (PPAR), CCAAT enhancer binding proteins (CEBP), and insulin signaling to marbling development in beef cattle. We have shown that PPAR is positively related (P < 0.05) to marbling development as it can account for 23 percent of the variation in marbling in beef cattle. In a seperate study, CEBP beta was increased (P < 0.05) and hypothesized to lead to greater marbling development. Other studies focusing on insulin signaling are being conducted, analyzed, and we anticipate to publish this in 2017. Goal 2: Determine if marbling in beef cattle can be enhanced through applied feeding strategies (40% complete). We have shown that maternal nutrient restriction of protein and energy does not enhance (P > 0.05) marbling development in subsequent beef cattle offspring. We are conducting research to determine whether chromium supplementation and ruminal bypass long chain fatty acid supplementation can influence marbling deposition in beef cattle. We anticipate this data will be submitted for publication in 2017. Goal 3: Determine if beef tenderness is affected by different management strategies (10% complete). Cattle have been fed using varying levels of growth promoting technologies including implants, inophores and beta agonists to determine the effect of these technologies on beef tenderness. Meat quality analysis will be conducted on the meat products from these animals in the future to determine the effects on tenderness and palatability.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: 1. Webb, M. J., J. J. Kincheloe, M. K. Luebbe, A. A. Harty, R. R. Salverson, S. M. Scramlin-Zuelly, K. R. Underwood, K. C. Olson, A. D. Blair. 2016 Effect of nursing calf implant timing on growth performance and carcass characteristics. Proceedings of the 69th Reciprocal Meats Conference, San Angelo, TX, Amer. Meat Sci. Assoc. (Abstract # 15).
• Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: 2. Rode, H. R., Z. K. Smith, R. H. Pritchard, A. D. Blair, K. R. Underwood. 2016. The impact of chromium supplementation on carcass characteristics and PPAR gamma expression in beef cattle. Proceedings of the 69th Reciprocal Meats Conference, San Angelo, TX, Amer. Meat Sci. Assoc. (Abstract # 86).
• Type: Journal Articles Status: Published Year Published: 2015 Citation: 1. Mohrhauser, D. A., A. R. Taylor, K. R. Underwood, R. H. Pritchard, A. E. Wertz-Lutz, and A. D. Blair. The influence of maternal energy status during mid-gestation on beef offspring carcass characteristics and meat quality. Journal of Animal Science 93:786-793.
• Type: Journal Articles Status: Published Year Published: 2015 Citation: 2. Mohrhauser, D. A., A R. Taylor, M. G. Gonda, K. R. Underwood, R. H. Pritchard, A. E. Wertz-Lutz, A. D. Blair. The influence of maternal energy status during mid-gestation on beef offspring tenderness, muscle characteristics, and gene expression. Meat Science 110:201-211.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: 2. Jennings,T. D., M G. Gonda, K. R. Underwood, A. E. Wertz-Lutz, A. D. Blair. The influence of maternal nutrition on the expression of genes responsible for adipogenesis and myogenesis in the bovine fetus. Animal. 10(10): 1697-705.