Meat Science Commons^™

Effects Of Forage Quality, Mdgs, And Monensin On Performance, Methane Concentration, And Ruminal Fermentation Of Growing Cattle, Anna C. Pesta, Andrea K. Watson, Samodha Fernando, Galen E. Erickson

Samodha C. Fernando

A growing study was conducted to evaluate a novel method for measuring methane concentration by feedlot cattle, and to determine the effects of forage quality, inclusion of modified distillers grains plus solubles (MDGS), and presence or absence of monensin on performance, methane concentration, and rumen fermentation characteristics. Performance was improved by use of high-quality forage and MDGS, while response to monensin was variable across basal diet type. Response of methane concentration and volatile fatty acid (VFA) profile due to diet was variable and subject to multiple interactions, reflecting the complexity of the microbial processes involved within the rumen.

Differences In Fecal Bacterial Community Composition Between Beef Steers Which Are High-Shedders And Low-Shedders Of Shiga Toxin-Producing Escherichia Coli (Stec), Nirosh D. Aluthge, Yoshitha A. Wanniarachchi, Brandon L. Nuttelman, Cody J. Schneider, Terry J. Klopfenstein, Galen E. Erickson, Samodha C. Fernando

Samodha C. Fernando

The community composition of the fecal microbiota was compared between beef steers which were high-shedders and low-shedders of Shiga toxin-producing Escherichia coli. Based on Shannon and Chao 1 diversity indices, the high-shedders had a more diverse fecal bacterial community than the low-shedding steers. Members of the genus Prevotella were observed as being more abundant in the low-shedders compared to the high-shedders, while Succinivibrio were more abundant in the high-shedders. Isolation of specific bacteria which are significantly more abundant in low-shedders may pave the way to developing direct-fed microbials which are effective in reducing STEC shedding among high-shedding beef steers.

Comparison Of Three Cidr-Based Fixed-Time Ai Protocols In Beef Heifers, G.A. Bridges, J.A. Walker, S.L. Lake, S.G. Kruse, S.L. Bird, B.J. Funnell, R. Arias, J.K. Grant

Julie Walker

Managing Annual Cow Costs, Julie Walker

Julie Walker

Application Of Broken-Line Analysis To Assess Floor Space Requirements Of Nursery And Grower-Finisher Pigs Expressed On An Allometric Basis, Anna K. Johnson, H. W. Gonyou, M. C. Brumm, E. Bush, J. Deen, S. A. Edwards, T. Fangman, J. J. Mcglone, M. Meunier-Salaun, R. B. Morrison, H. Spoolder, P. L. Sundberg

Anna K. Butters-Johnson

Few issues in swine production are as complex as floor space allowances. One method for pork producers to calculate floor space allowance (A) is to convert BW into a 2-dimensional concept yielding an expression of A = k * BW(0.667). Data on ADG, ADFI, and G:F were obtained from published peer-reviewed studies. Five data sets were created: A = grower-finisher pigs, fully slatted floors, and consistent group size; B = grower-finisher pigs and fully slatted floors (group size did not need to be consistent); C = grower-finisher pigs, partially slatted floors, and consistent group size; D = grower-finisher pigs, partially …

Environmental Prevalence And Persistence Of Salmonella Spp. In Outdoor Swine Wallows, Anna K. Johnson, T. R. Callaway, J. L. Morrow, J. W. Dailey, F. M. Wallace, E. A. Wagstrom, J. J. Mcglone, A. R. Lewis, S. E. Dowd, T. L. Poole, T. S. Edrington, R. C. Anderson, K. J. Genovese, J. A. Byrd, R. . Harvey, D. J. Nisbet

Anna K. Butters-Johnson

Swine can harbor Salmonella in their gastrointestinal tracts. It has been estimated that up to 48% of the U.S. swine herd may carry Salmonella. Housing sows in farrowing stalls has become controversial due to animal welfare-based criticisms. An alternative production system is to keep sows outdoors on pasture with access to individual farrowing huts. This study was designed to determine the effects of two production systems on indicator bacteria and Salmonella of sows housed indoors in farrowing stalls (n = 52) compared to sows housed outdoors (n = 52) in English style huts. Each farrowing radial contained one wallow, from …

Effect Of Water Sprinkling On Incidence Of Zoonotic Pathogens In Feedlot Cattle, Anna K. Johnson, J. L. Morrow, F. M. Mitloehner, M. L. Galyean, J. W. Dailey, T. S. Edrington, R. C. Anderson, K. J. Genovese, T. L. Poole, S. E. Duke, T. R. Callaway

Anna K. Butters-Johnson

Heat stress and dusty conditions are common challenges for cattle during the summer, and a typical method of alleviating these problems involves sprinkling cattle and pens with water. The effect of sprinkling water on the incidence of zoonotic pathogens has not been previously studied. Four pens of heifers (n = 41) were cooled using sprinklers, and four pens (n = 43) served as controls. Heifers were crossbred Charolais, with white and red hair coats. Sprinkling was initiated when cattle were on full concentrate feed (July). Fecal samples, hide swipes, and BW were collected on d 0, 28, 63, 95, and …

Review: Compilation Of The Scientific Literature Comparing Housing Systems For Gestating Sows And Gilts Using Measures Of Physiology, Behavior, Performance, And Health, Anna K. Johnson, J. J. Mcglone, E. H. Von Borell, J. Deen, D. G. Levis, M. Meunier-Salaun, J. Morrow, D. Reeves, J. L. Salak-Johnson, P. L. Sundberg

Anna K. Butters-Johnson

The objective of this review was two-fold. First, a series of meta-analyses (analyses of treatment effects across studies) were performed on available data from scientific literature to determine whether sow behavior, performance, or physiology differed for sows in group pens or individual stalls. Second, research publications in areas of performance and health, physiology, and behavior of pregnant gilts and sows in studies that directly compared gestation sow housing systems were summarized. Common systems were stalls, tethers, and various types of group housing systems. Results of meta-analyses showed that the average levels of productivity, oral-nasal-facial behaviors (ONF), and blood cortisol were …

Development Of An Enzyme-Linked Immunosorbent Assay (Elisa) For Quantification Of Skeletal Muscle Calpastatin, M. E. Doumit, Steven M. Lonergan, J. R. Arbona, J. Killefer, M. Koohmaraie

Steven M. Lonergan

An indirect antibody ELISA was developed for rapid and sensitive quantification of skeletal muscle calpastatin. Polyclonal antibodies were raised in rabbits against recombinant calpastatin, corresponding to domains 2, 3, and 4 of bovine skeletal muscle calpastatin. Western blot analysis revealed that these antibodies specifically recognize an immunoreactive calpastatin protein of approximately 130 kDa in prerigor skeletal muscle extracts. The intensity of the immunoreactive bands corresponds qualitatively with assayable calpastatin activity. For ELISA development, optimum dilutions of sample, primary anti-calpastatin antibody, and peroxidase-conjugated secondary antibody were determined by titration. A dilution optimum for coating of Immulonâ 4 (Dynatech) plates was observed …

A Muscle Hypertrophy Condition In Lamb (Callipyge): Characterization Of Effects On Muscle Growth And Meat Quality Traits, M. Koohmaraie, S. D. Shackelford, T. L. Wheeler, Steven M. Lonergan, M. E. Doumit

Steven M. Lonergan

The present experiment was conducted to determine the effect of the callipyge phenotype on traits affecting muscle growth and meat tenderness. Dorset wethers (n = 40) that were either carriers or non-carriers were fed grain and slaughtered at 169 d of age. Callipyge phenotype did not affect ( P > .05) slaughter weight, hot carcass weight, or weights of the heart, spleen, viscera, kidney-pelvic fat, head, and pelt; however, callipyge lambs had a higher dressing percentage and lighter lungs, liver, and kidneys ( P < .01). Callipyge lambs had reduced fat thickness and marbling score and higher leg scores and longissimus area (34%). Adductor (30%), biceps femoris (42%), gluteus group (31%), longissimus (32%), psoas group (20%), quadriceps femoris (18%), semimembranosus (38%), and semitendinosus (26%) weights were higher in the callipyge phenotype ( P < .01); however, phenotype did not affect ( P > .05) weights of infraspinatus or supraspinatus. Longissimus pH and temperature declines were not affected ( P > .05) …

Delayed-Incubation Method For Microbiological Analysis Of Environmental Specimens And Samples, James S. Dickson, M. H. Brodsky, C. A. Davidson, M. J. Pettis, T. L. Tieso

James S. Dickson

Five laboratories compared the quantitative recovery of heterotrophic bacteria, yeasts and molds, coliforms, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus from a variety of naturally contaminated food and water samples, using traditional incubation procedures and a delayed-incubation method. Refrigeration of inoculated media for up to 3 days prior to incubation was shown to be a viable option for many quantitative analyses, but needs to be validated for each application. Some inoculated media withstood refrigeration for up to 7 days prior to incubation without any detrimental effect on the recovery of target cells, while the incubation of other media for similar …

Relationship Of Restriction Fragment Length Polymorphisms (Rflp) At The Bovine Calpastatin Locus To Calpastatin Activity And Meat Tenderness, Steven M. Lonergan, C. W. Ernst, M. D. Bishop, C. R. Calkins, M. Koohmaraie

Steven M. Lonergan

Restriction fragment length polymorphisms (RFLP) have been identified at the bovine calpastatin locus. The objective of the present study was to determine whether these polymorphisms are related to variations in calpastatin activity or beef tenderness in unrelated animals of mixed breeding. A sample of 83 crossbred steers from sires representing eight different breeds was examined to determine this relationship. A 2.2-kb cDNA coding for domains 2 through 4 plus a 3¢ untranslated region of bovine skeletal muscle calpastatin was used as a probe for calpastatin RFLP. Polymorphisms were found using the restriction enzymes BamHI and EcoRI. Polymorphic restriction fragments for …

Cell Surface Charge And Initial Attachment Characteristics Of Rough Strains Of Listeria Monocytogenes, James S. Dickson

James S. Dickson

The relative negative surface charge and hydrophobicity of four bacterial strains were evaluated by gravity flow and spin column methods. There was no significant difference between the two methods, indicating that spin column chromatography is an acceptable alternative method of determining cell surface charge or hydrophobicity. Six strains of Listeria monocytogenes which exhibited rough colony appearance were evaluated for surface charge and hydrophobicity and their ability to contaminate beef muscle tissue. With one exception, all of the rough strains exhibited greater net negative surface charge and reduced ability to contaminate beef during the initial stages of attachment. Since greater net …

Antimicrobial Effects Of Trisodium Phosphate Against Bacteria Attached To Beef Tissue, James S. Dickson, C. G. Nettles Cutter, G. R. Siragusa

James S. Dickson

Sliced beef tissue was artificially contaminated with Salmonella typhimurium, Listeria monocytogenes and Escherichia coli OI57:H7. The contaminated tissue was immersed in 8, 10 and 12% solutions of trisodium phosphate at 25, 40 and 55°C with contact times of up to 3 min. The concentration of the trisodium phosphate solution was not a significant factor in reducing the populations of the bacteria on either lean or adipose tissue. Reductions in bacterial populations of I to 1.5 loglocycles were obtained on lean tissue contaminated with the gram-negative pathogens, although less reduction in population was seen with L. monocytogenes. Greater reductions in bacterial …

Temporal Response Of Rabbits To B-Adrenergic Agonist Feeding: Tissue Weight, Calpain And Calpastatin Activities, And Nucleic Acid And Protein Concentration, T. D. Pringle, Steven M. Lonergan, C. R. Calkins, S. J. Jones, P. S. Miller, M. Koohmaraie

Steven M. Lonergan

Forty-eight crossbred rabbits were used in three replications of a 2 x 4 factorial arrangement to investigate the short-term responses of tissue accretion, calpains and calpastatin activity, and nucleic acid and protein concentrations to 6- adrenergic agonist (BAA) feeding. Rabbits were fed a 17% CP diet with or without 7 ppm of L644,969 and slaughtered after 1, 4, 8, or 16 d of treatment. Empty body dressing percentage and biceps femoris weight (as a percentage of empty body weight [EBWI) were significantly higher in the treated rabbits than in the controls after 16 d of treatment. Heart and liver weights …

Bacterial Starvation Stress And Contamination Of Beef, James S. Dickson, J. F. Frank

James S. Dickson

Salmonella typhimurium, Listeria monocytogenes, ad Escherichia coli 0157;H7 were starved by suspending washed cells in phosphate buffer for 5 days at 10, 25 or 37 degrees C. Starved bacteria were evaluated for their ability to attach to beef tissue and their sensitivity to acetic acid sanitizing. Starvation stress generally decreased the numbers of bacteria which attached to the tissue when compared to control bacterial cultures grown to late logarithmic growth phase. Starvation temperature was negatively correlated to the numbers of attached bacteria. Starvation slightly increased the sensitivity of attached S. typhimurium and L. monocytogenes cells to acetic acid, but did …

Isolation Of Listeria Spp. From Feces Of Feedlot Cattle, James S. Dickson, G. R. Siragusa, E. K. Daniels

James S. Dickson

Healthy feedlot beef cattle were surveyed for the presence of Listeria spp. in fecal grab samples taken over 3 months. Composite samples were made from 224 individual animals each month. Listeria monocytogenes was isolated from one composite sample (4%) from the first sampling and not from the subsequent two. Listeria innocua was found in composite samples from all three samplings at levels of 17, 9, and 35%, respectively. From the individual samples comprising the Listeria spp.—positive composites, L. monoytogenes was isolated from one sample (3%) in the second sampling but not in the first or third samplings. L. innocua was …

A Computer-Controlled Spray Chill Unit For Red Meat Carcasses, Maynard E. Anderson, James S. Dickson, Mark M. Hulse, Scott T. Drummond, John D. Crouse, Robert T. Marshall

James S. Dickson

A computer controlled and operated spray chill unit which can be used in future research studies for both spray chilling and decontamination of red meat carcasses is described. The unit consists of two parts: (1) an electromechanical system, and (2) a data acquisition/control system. Design concepts for the spray chill system are (1) versatility, (2) rapid change of spray parameters, and (3) computer control of the electromechanical system. An added feature is the computer data collection system for recording information related to each carcass (pH of muscle, surface and internal tissue temperatures, and weights of each half carcass during the …

A Computer Controlled Spray Chill Unit For Red Meat Carcasses, Maynard E. Anderson, James S. Dickson, Mark M. Hulse, Scott T. Drummond, John D. Crouse, Robert T. Marshall

James S. Dickson

A computer controlled and operated spray chill unit which can be used in future research studies for both spray chilling and decontamination of red meat carcasses is described. The unit consists of two parts: (1) an electromechanical system, and (2) a data acquisition/control system. Design concepts for the spray chill system are (1) versatility, (2) rapid change of spray parameters, and (3) computer control of the electromechanical system. An added feature is the computer data collection system for recording information related to each carcass (pH of muscle, surface and internal tissue temperatures, and weights of each half carcass during the …

Predicting The Growth Of Salmonella Typhimurium On Beef By Using The Temperature Function Integration Technique, James S. Dickson, G. R. Siragusa, J. E. Wray Jr.

James S. Dickson

Lag and generation times for the growth of Salmonella typhimurium on sterile lean beef were modeled as functions of cooling time under various carcass-chilling scenarios. Gompertz growth models were fit to the log10 colony counts over time at each of six temperatures in the range of 15 to 40 degrees C. Lag and generation times were defined as the points at which the second and first derivatives, respectively, of each growth curve attained a maximum. Generation time and lag time parameters were modeled as functions of temperature by use of exponential-decay models. The models were applied to typical beef carcass-cooling …

Microbiological Decontamination Of Food Animal Carcasses By Washing And Sanitizing Systems: A Review, James S. Dickson, Maynard E. Anderson

James S. Dickson

Microbial contamination of animal carcasses is a result of the necessary procedures required to process live animals into retail meat. The contamination can be minimized by good manufacturing processes, but the total elimination of foodborne pathogenic microorganisms is difficult, if not impossible. A variety of methods have been developed to reduce the levels of contaminating bacteria on carcasses, although most of the current methods focus on washing and sanitizing procedures. The commonly used sanitizing agents include hot water, chlorine, and short-chain organic acids. The effectiveness of these compounds varies by the concentration used, the temperature of the sanitizers and contact …

Inhibition Of Listeria Monocytogenes On Beef Tissue By Application Of Organic Acids Immobilized In A Calcium Alginate Gel, James S. Dickson, Gregory R. Siragusa

James S. Dickson

Organic acids added to calcium alginate gels and immobilized on lean beef tissue inoculated with LLtetia monocytogenes (Lm) reduced the population significantly more than did acid treatment alone. Lactic acid (1.7% v/v) immobilized in alginate reduced counts by 1.3 log,, units vs 0.03 log unit decrease from the acid treatment alone. Acetic acid (2% v/v) reduced counts 1.5 and 0.25 log units, respectively. Over 7 days, Lm proliferated in samples without acid and/or alginate treatment. Differential counts on selective and non-selective agars indicated sublethal cellular injury occurred. Alginate coatings did not enhance acid inhibition on fat tissue. Immobilized agents may …

Acetic Acid Action On Beef Tissue Surfaces Contaminated With Salmonella Typhimurium, James S. Dickson

James S. Dickson

Beef tissue surfaces (lean and fat) were artificially contaminated with Salmonella typhimurium and then sanitized with 2% acetic acid. The reduction in bacterial population by the acid treatment was consistently proportional to the initial inoculum level for both tissue types. Increasing the amount of organic material in the inoculating menstra reduced the bactericidal effects of acetic acid on Salmonella typhimurium on fat tissue, although there was no change in effectiveness on lean tissue. Acid treatment sublethally injured about 65% of the population on both lean and fat tissue, and the residual effects of the acid resulted in a 1 log …

Control Of Salmonella On Beef Tissue Surfaces In A Model System By Pre- And Post-Evisceration Washing And Sanitizing, With And Without Spray Chilling, James S. Dickson, Maynard E. Anderson

James S. Dickson

Beef tissue was inoculated with a nalidixic acid resistant strain of Salmonella California and processed under conditions simulating pre- and post-evisceration carcass washing and sanitizing. These treatments, using distilled water to wash and 2% acetic acid to sanitize, reduced the population of salmonellae by as much as 2-log10 cycles when compared to samples which were washed only in distilled water. Increasing the acid temperature to 55°C reduced the bacterial populations further. Spray chilling, when used in series with the pre- and post-evisceration treatments, apparently resulted in recovery of some injured Salmonella.

Contamination Of Beef Tissue Surfaces By Cattle Manure Inoculated With Salmonella Typhimurium And Listeria Monocytogenes, James S. Dickson

James S. Dickson

Contamination of beef lean and fat tissue surfaces by Salmonella typhimurium and Listeria monocytogenes was evaluated using phosphate buffer or sterilized manure as an inoculation menstruum. Immersion in inoculated phosphate buffer resulted in an increase in numbers of attached cells during the 120 min inoculation for both bacterial species. Tissue immersed in inoculated manure generally showed an increase in cell numbers up to 10 min of immersion with only slight increases in cell numbers from lOto 120 min. Fewer cells attached to either tissue type from the manure inoculum (P<0.05), although actual numerical differences were small.

Attachment Of Salmonella Typhimurium And Listeria Monocytogenes To Glass As Affected By Surface Film Thickness, Cell Density, And Bacterial Motility, James S. Dickson, E. K. Daniels

James S. Dickson

With equal cell densities, surface film thickness did not influence the numbers &Salmonella typhimurium and Listeria monocytogenes cells which attached to glass. Motile L. monocytogenes cells had a greater cell surface charge and generally attached in higher numbers than non-motile cells.

Control Of Salmonella Typhimurium, Listeria Monocytogenes, And Escherichia Coli 0157:H7 On Beef In A Model Spray Chilling System, James S. Dickson

James S. Dickson

Simulated water spray chilling cycles were modified to include acetic acid as a sanitizer. The modified cycles were tested for effectiveness in reducing levels of S. typhimutium, L. monocyfogenes, and E. coli 0157:H7 on beef lean and fat tissue. Reductions of up to 3 log cycles were obtained for all three bacterial species on fat tissue. Reduction was less on lean tissue with the same treatments, although the modified cycles reduced populations when compared to the control cycle.

Storage And Bacterial Contamination Effects On Myofibrillar Proteins And Shear Force Of Beef, James S. Dickson, John D. Crouse, M. Koohmaraie

James S. Dickson

Thirty-two steaks from the longissimus muscle, fifth rib to third lumbar vertebra, were obtained from youthful carcass beef. Half were sterilized by ultraviolet light and all vacuum packaged and stored for 1, 14, 28 or 57 days at 2°C. After storage, steaks were examined for microbial populations, myofibril fragmentation index (MFI), cooking characteristics and shear force (SF). Aerobic and anaerobic counts decreased during storage. Psychrotrophic counts were low throughout. Sterilization had no effect on SF or MFI. Cooking loss tended (P < 0.09) to increase with time of storage. SF values decreased and MFI values increased through day 14, but remained relatively constant after that. Results of SDS-PAGE, SF and MFI indicate major changes in proteolysis of myofibrils and tenderness were completed by day 14.

Attachment Of Salmonella Typhimurium And Listeria Monocytogenes To Beef Tissue: Effects Of Inoculum Level, Growth Temperature And Bacterial Culture Age, James S. Dickson

James S. Dickson

The effects of inoculum level, growth temperature and culture age on the attachment of Salmonella typhimurium and Listeria monocytogenes to beef tissue surfaces were evaluated. An increase in inoculum level resulted in an increase in the number of attached cells for both bacteria which was proportional to the increase in inoculum. Bacteria grown at 23°C attached in higher numbers flVO5) to fat tissue than bacteria grown at 37°C or at 37°C followed by 24 h at 5°C. Growth temperature did not affect attachment to lean tissue for either bacterium. Overnight cultures of both bacteria attached in greater numbers 0VO.05) to …

Surface Moisture And Osmotic Stress As Factors That Affect The Sanitizing Of Beef Tissue Surfaces, James S. Dickson

James S. Dickson

The use of osmotic stress or desiccation in combination with 2% acetic acid reduced the numbers of Salmonella typhimurium or Listeria monocytogenes on beef tissue to a greater degree than the acid alone. Bacteria were osmotically stressed by NaCl, CaCl2, or sucrose solutions. Pre-washing with 20% NaCl followed by sanitizing with acetic acid reduced the numbers of S. typhimurium an additional 1.5-to 2-log cycles compared with acetic acid alone. Similar reductions were seen by allowing the tissue surfaces to dry before the application of the acid. Desiccation in combination with acetic acid was also effective in reducing the numbers of …