Research - Beef Cattle

Beef Quality and Muscle Physiology

The goal of the Updike lab is to conduct research which will answer questions about predicting and producing highly palatable beef. The current focus is to develop methods for beef producers, particularly small, direct to consumer marketers, to determine the palatability of a given carcass prior to selling using proteomic methods and to evaluate factors in the muscle microenvironment which inhibit intramuscular adipogenesis (marbling) using cell culture and proteomics.

Currently, beef carcasses are segregated into palatability classes based on both physiological age and the amount of intramuscular adipose. Such segregation is only moderately successful in predicting the palatability of the beef, with tenderness being especially inconsistent to consumers. To improve this, a method that can predict tenderness of beef after chilling but prior to fabrication (between 36-48 h) and without being destructive or costly, must be developed.

A principle component analysis was performed on the 36 h longissimus dorsi sample by separating the proteins into high salt soluble fractions and high salt insoluble fractions. Sarcomere lengths were ascertained at both pre- (0 h) and post rigor (36 h) time points. Warner Bratzler shear force determinations were made on steaks aged for both 7 and 14 d. Pre-rigor, post-rigor and the change in sarcomere length were not correlated with 7 d, 14 d or change in WBS. Proteomic analysis and reverse step wise multiple regression identified bands which were predictive of or associated with 7 d WBS, 14 d WBS, the change in WBS and the post rigor sarcomere length ( p < 0.05). Numerous proteins were identified implicating a variety of cellular processes such as the myofibrillar degradation, glycolysis and calcium regulation.

Electropherogram and electrophoretic image of a representative lane of the high salt soluble fraction and the high salt insoluble fraction. Bands identified by letters were found to be predictive of and associated with the independent variables of 36 h SL, 7 d WBS, 14 d WBS and the change in WBS from d 7 to d 14. These bands were sequenced by Mass Spectrometry nano-LC/MC/MC. Updike, Zapata, Zerby and Wick. 2007. Predicting Beef Tenderness Using Proteomic Analysis of 36 h Postmortem Muscle. J. Anim Sci. vol 85 suppl 1.

While quality grade is not a perfect predictor of tenderness, it is a reasonable predictor of overall palatability, flavor and juiciness. In addition to the physiological age of the animal, marbling in the longissimus dorsi is the criteria for determining quality grade. Marbling is the amount of visible intramuscular adipose depots. Intramuscular adipose is dependent upon both proliferation of preadipocytes and subsequent differentiation into lipid storing adipocytes. This proliferation and differentiation occurs within the muscle microenvironment, consisting of myotubes and fibroblasts. To test the affect of the muscle microenvironment on preadipocyte proliferation, conditioned media from myotubes, fibroblasts and preadicpoytes, both subcutaneous (SQ) and intramuscular (IM) was used to assay preadipocyte proliferation. Preadipcoytes cultured with fibroblast conditioned media showed no proliferation ( p < 0.01). Preadipocytes cultured with myotubes conditioned media proliferated at a reduced rate compared to preadipocytes cultured with IM or SQ conditioned media ( p < 0.01). In addition, SQ conditioned media caused increased proliferation of preadipocytes compared to IM conditioned media. These results demonstrate that multiple mechanisms regulate the proliferation of preadipocytes. Because of the multiplicity of pathways through which preadipocyte proliferation is regulated, novel methods for increasing intramuscular adipose depots may be developed once these pathways are determined.

Proliferation of intramuscular preadipocytes cultured with various conditioned media made from subcutaneous preadipocytes, intramuscular preadipocytes, fibroblasts or myotubes. A treatment x time interaction was present (p < 0.05). Means with different superscripts differ (P < 0.05). Updike and Wick. 2006.

Awards and Honors

• NSF Graduate Research Fellow, 2003

Extension

As the Extension Beef Specialist for the State of Maryland, I am responsible for coordinating beef extension programming throughout the state and serving as a resource for the stakeholders, including beef producers, beef processors, extension educators and the general public. My extension outreach focuses on improving the quality of beef from producers in Maryland. I am currently working with Extension Educators, livestock marketing specialists and allied industry personnel to hold a beef carcass contest which is open not just to youth, but also to producers in the Mid Atlantic region. This contest was designed to provide carcass feedback to producers so that they will have the information to determine the efficacy of their management practices on beef quality. In addition to a carcass contest, a live fat cattle evaluation contest and demonstration is planned to teach both your and adults how to look at a live animal and predict carcass merit. More information may be found at the following website: http://ansc.umd.edu/extension/beef/MABC_index.cfm?directory=MABC_home.cfm

I am also the faculty advisor to Wye Angus
http://ansc.umd.edu/facilities/index.cfm?directory=MERC_beef_unit.cfm
http://www.agnr.umd.edu/agResearch/RECs/WREC/wyeAngus/index.cfm

As advisor to Wye Angus, I help facilitate research using Wye cattle as well assisting the farm crew with management decisions.

Publications

Representative Publications

• MS Updike, JC Sawdy, LS Wang, S Liu, YW Huang, W Ye, WB Farrar, YC Lin and M Wick. 2007. Primary cultured human breast epithelial cells up-regulate protein disulfide isomerase in response to zeranol. Anticancer Research. 27:407-410
• Updike, M.S., H. Zerby, K.L. Utrata, M. Lilburn, G. Kaletunc, and M. Wick. 2006. Proteins Associated with Thermally Induced Gelling of Turkey Breast Meat. J. Food Sci. 71: 398-402
• Updike, M.S., M.E. Davis, L. Wang, Y. Huang, M. Wick, and Y.C. Lin. 2005. Decreased MCF-7 Breast Cancer Cell Proliferation by Serum from a Selected Line of Beef Cattle. Anticancer Research. 25: 871
• Updike, M.S., H. Zerby, J.C. Sawdy, M. Lilburn, G. Kaletunc, and M. Wick. 2004. Turkey Breast Meat Functionality: Differences Among Turkeys Selected for Body Weight and/or Breast Yield. Meat Science. 71: 706