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Full-Text Articles in Life Sciences

Carbon Monoxide Packaging For Fresh Pork, Travis R. Krause, Joseph G. Sebranek, Mark S. Honeyman Jan 2004

Carbon Monoxide Packaging For Fresh Pork, Travis R. Krause, Joseph G. Sebranek, Mark S. Honeyman

Animal Industry Report

Injected and non-injected pork chops were packaged in aerobic, vacuum and modified atmosphere [with and without carbon monoxide (CO)] packages to evaluate quality and shelf life during refrigerated storage.Color stability and attractiveness was dramatically improved by the carbon monoxide treatment over any other packaging treatment in this study.This effect permits use of high carbon dioxide atmosphere for packaging of fresh meat to achieve improved shelf life for both color and microbial quality


Processing Treatments For Control Of Listeria Monocytogenes On Frankfurters, Chih-Ming Chen, Joseph G. Sebranek, James S. Dickson, Aubrey F. Mendonca Jan 2004

Processing Treatments For Control Of Listeria Monocytogenes On Frankfurters, Chih-Ming Chen, Joseph G. Sebranek, James S. Dickson, Aubrey F. Mendonca

Animal Industry Report

Frankfurters were surface inoculated with a 5-strain mixture of Listeria monocytogenes then treated with a pediocin (ALTATM 2341), post-packaging pasteurization with heat or post-packaging irradiation.All treatments effectively reduced L. monocytogenes numbers but combinations, particularly pediocin with heat or with irradiation were most effective for both reducing L. monocytogenes and suppressing growth of survivors. Pediocin and irradiation treatments were synergistic and achieved the greatest control of L. monocytogenes of all the treatments studied.These treatments offer meat processors alternatives to improve control of L. monocytogenes on processed meats.


Effect Of Dietary Vitamin E And Irradiation On Lipid Oxidation, Color, And Volatiles Of Fresh And Previously Frozen Turkey Breast Patties, K. C. Nam, B. R. Min, H. Yan, E. J. Lee, Irene V. Wesley, M. J. Zhu, Aubrey F. Mendonca, Dong U. Ahn Jan 2004

Effect Of Dietary Vitamin E And Irradiation On Lipid Oxidation, Color, And Volatiles Of Fresh And Previously Frozen Turkey Breast Patties, K. C. Nam, B. R. Min, H. Yan, E. J. Lee, Irene V. Wesley, M. J. Zhu, Aubrey F. Mendonca, Dong U. Ahn

Animal Industry Report

When dietary TA was increased from 0 to 200 IU/kg diet, plasma and muscle vitamin E levels increased by 5- and 4-fold, respectively. Dietary TA at 100 IU/kg diet significantly improved the storage stability of turkey breast, and it was more distinct in irradiated than nonirradiated meats. Both irradiation and dietary TA increased a*-values of turkey breast meat, but irradiation had a stronger impact. The redness of meat decreased during the 7-d storage, but irradiated meat maintained redder color than nonirradiated. Irradiated meat produced more sulfur volatiles and aldehydes than nonirradiated meats, and dietary TA effectively reduced ...


Quality Characteristics Of Irradiated Chicken Breast Rolls From Broilers Fed Different Levels Of Conjugated Linoleic Acid, M. Du, K. C. Nam, S. J. Hur, H. Ismail, Y. H. Kim, Dong U. Ahn Jan 2004

Quality Characteristics Of Irradiated Chicken Breast Rolls From Broilers Fed Different Levels Of Conjugated Linoleic Acid, M. Du, K. C. Nam, S. J. Hur, H. Ismail, Y. H. Kim, Dong U. Ahn

Animal Industry Report

Dietary CLA treatment reduced color a*- and b*-values of cooked chicken breast rolls. Sensory panels rated the color of cooked chicken rolls with CLA treatments darker than the control. The production of CO in cooked chicken rolls increased dramatically after irradiation and was correlated with the increased redness of cooked chicken rolls after irradiation. Irradiation greatly increased volatile production and induced a metallic off-flavor in chicken rolls. The hardness of chicken rolls increased and juiciness decreased as the dietary level of CLA increased, and consumer preferred the color of cooked chicken rolls after irradiation to the nonirradiated ones. Although ...


Improving Health Benefits Of Beef And Milk: A Field Study, Roberto N. Sonon Jr., Donald C. Beitz, Allen H. Trenkle Jan 2004

Improving Health Benefits Of Beef And Milk: A Field Study, Roberto N. Sonon Jr., Donald C. Beitz, Allen H. Trenkle

Animal Industry Report

A study was conducted to assess the concentration of conjugated linoleic acid in beef and milk from various farms in northeast Iowa and southwest Wisconsin that represent a broad range of management systems.Intensively pastured cows produced milk with CLA concentrations that were about 3- to 4-fold greater than the initial concentration. Ribeye steaks from cattle finished on a combination of pasture and concentrates were higher in CLA content than steaks from cattle finished on conserved forages plus concentrates.Therefore, pasture grazing is an effective method to improve the healthfulness of milk and beef.


Identification Of A Role For The Tyrosine Kinase Jak2 In Both Skeletal Muscle Mitogenesis And Myogenesis, Symantha A. Miller, James M. Reecy Jan 2004

Identification Of A Role For The Tyrosine Kinase Jak2 In Both Skeletal Muscle Mitogenesis And Myogenesis, Symantha A. Miller, James M. Reecy

Animal Industry Report

This study was conducted to investigate what roles JAK2 might play in skeletal myoblast proliferation and terminal differentiation.These results represent the first characterization of the requirement of JAK2 in skeletal muscle proliferation, and suggest a novel role, potentially independent of kinase activity, for JAK2 in skeletal muscle myogenesis.


Use Of Linear And Non-Linear Growth Curves To Describe Body Weight Changes Of Young Angus Bulls And Heifers, Abebe T. Hassen, Doyle E. Wilson, Gene H. Rouse, Richard G. Tait Jr. Jan 2004

Use Of Linear And Non-Linear Growth Curves To Describe Body Weight Changes Of Young Angus Bulls And Heifers, Abebe T. Hassen, Doyle E. Wilson, Gene H. Rouse, Richard G. Tait Jr.

Animal Industry Report

The objectives of the current study were to describe bodyweight (BW) changes of purebred Angus bulls and heifer and to evaluate bias in the adjustment of weaning weight measures to a 205-d age.Linear and non-linear growth functions were used to evaluate changes in BW.Models used were a simple linear regression model fitting cubic polynomial of age at measurement (model I) and a Logistic model (model II) .Predicted mature weight for bulls was 763 kg (1,678.6 lbs.) as compared to 541.9 kg (1192.2 lbs.) for heifers.Bulls attained a maximum average daily weight gain (ADG ...


Identifying Genetic Cause Of Dwarfism In American Angus Cattle, Bishnu P. Mishra, Julie A.L. Cavanagh, James M. Reecy Jan 2004

Identifying Genetic Cause Of Dwarfism In American Angus Cattle, Bishnu P. Mishra, Julie A.L. Cavanagh, James M. Reecy

Animal Industry Report

Dwarfism in American Angus was a major cause of concern in the 1970’s. Until recently when several calves from some sire x dam crosses resulted in phenotypically dwarf calves not cases have been observed since then. Six affected calves from 3 sire and 5 dam matings and unrelated normal Angus animals were genotyped for the presence of known mutations, which have been reported in Japanese brown and Australian Dexter cattle. We detected only wild-type alleles in dwarf and phenotypically normal Angus cattle, indicating that known mutations associated with Japanese brown cattle or Dexter dwarfism are not responsible for dwarfism ...


Characterization Of Gene Expression In Double-Muscled And Normal-Muscled Bovine Embryos, Carissa A. Steelman, Jacklyn K. Potts, James M. Reecy Jan 2004

Characterization Of Gene Expression In Double-Muscled And Normal-Muscled Bovine Embryos, Carissa A. Steelman, Jacklyn K. Potts, James M. Reecy

Animal Industry Report

Using suppressive subtractive hybridization, 19 genes were confirmed to be differentially expressed between double-muscled and normal bovine embryos. The identified genes play roles in several cellular processes, including transcription, cell proliferation, protein synthesis and degradation, and metabolism. These genes can provide insight into molecules with which myostatin may interact. This information could potentially aid in the development of strategies to improve lean tissue deposition in livestock species.


Development Of The Bovianalyser Cdna Bovine Microarray, Artur J.M. Rosa, Gang Ren, James M. Reecy Jan 2004

Development Of The Bovianalyser Cdna Bovine Microarray, Artur J.M. Rosa, Gang Ren, James M. Reecy

Animal Industry Report

DNA microarrays are powerful tools to analyze the expression pattern of thousands of genes simultaneously in response to treatments, during tissue differentiation or related to differences in traits such as marbling or disease resistance. We developed a bovine cDNA microarray, BoviAnalyser, containing 11,088 genes spotted in duplicate. A set of 10,608 ESTs was selected from MARC 1-4 libraries to include: 1) all the known genes, 2) unknown, putative or hypothetical genes expressed in muscle, liver or adipose. Functional assignments for these clones were compared to the human by BLASTx to add putative IDs to unknown genes. The selected ...


Effects Of Forage Maturity On Phosphorus Digestion In Beef Cows, Kelli Bormann, Wendy J. Powers, James R. Russell Jan 2004

Effects Of Forage Maturity On Phosphorus Digestion In Beef Cows, Kelli Bormann, Wendy J. Powers, James R. Russell

Animal Industry Report

For environmental reasons, minimizing phosphorus excretion from cattle is of great interest. Current estimates of forage phosphorus digestibility by cattle consider that phosphorus digestibility does not change with composition of the pasture. To better estimate phosphorus (P) excretion, estimates of P digestibility for forages of different compositions are needed. Four crossbred cow/calf pairs were stocked on four pastures managed with grazing (G) or grazing with hay removal (G/H). Forage was maintained in paddocks at 50% removal. Collected pasture samples and fecal samples from cows administered chromic oxide were analyzed for P, NDF, and ADL contents. Rumen evacuations of ...


Effect Of Feed Intake On Plasma Ghrelin Concentration In Beef Cattle, Aimee Wertz, Travis Knight, Amanda Kreuder, Michelle Bohan, Don Beitz, Allen H. Trenkle Jan 2004

Effect Of Feed Intake On Plasma Ghrelin Concentration In Beef Cattle, Aimee Wertz, Travis Knight, Amanda Kreuder, Michelle Bohan, Don Beitz, Allen H. Trenkle

Animal Industry Report

Two experiments were conducted to determine if ghrelin mRNA existed in ruminant digestive tract tissues and to establish the fluctuation in plasma ghrelin concentrations for fed and fasting steers. Tissues collected from the ruminant digestive tract indicate detectable ghrelin mRNA in the upper, middle, and lower portion of the abomasum and in the small intestine but no detectable ghrelin mRNA in the reticulum, omasum, and rumen. Plasma ghrelin concentrations are elevated by a fasting period that is as short as 22 h. Additionally, plasma ghrelin remain elevated throughout a 48-h fasting period. The magnitude of difference in plasma ghrelin concentration ...


Effects Of Replacing Corn Grain And Urea With Condensed Corn Distillers Solubles On Performance And Carcass Value Of Finishing Steers, Allen H. Trenkle, David Pingel Jan 2004

Effects Of Replacing Corn Grain And Urea With Condensed Corn Distillers Solubles On Performance And Carcass Value Of Finishing Steers, Allen H. Trenkle, David Pingel

Animal Industry Report

Ninety-six yearling steers weighing 850 lbs were used in a study to evaluate condensed distillers solubles (CDS) for a dry mill corn processing plant as a replacement for a portion of the corn grain and supplemental nitrogen in a finishing ration supplemented with urea. Condensed distillers solubles were fed at 0%, 4%, 8% and 12% of ration dry matter in a 109-day experiment. Feeding CDS at these levels had no effect on performance of the cattle, carcass measurements or carcass value in a value-based grid. The calculated replacement value of CDS in this study was considerably less than observed in ...


A Summary Of Feeding Market Cows For The White Fat Cow Market, Daryl R. Strohbehn, W. Darrell Busby, Dennis D. Dewitt, Perry Beedle Iii Jan 2004

A Summary Of Feeding Market Cows For The White Fat Cow Market, Daryl R. Strohbehn, W. Darrell Busby, Dennis D. Dewitt, Perry Beedle Iii

Animal Industry Report

Three groups of culled market cows were fed high concentrate rations at three locations in Iowa to demonstrate the possibilities of finishing for the “White Fat Cow” market. Final shrunk weights ranged from 1378 to 1609 pounds, while average daily gains ranged from 2.78 to 3.87 pounds daily on a 70 to 90 day program. Dry matter feed efficiency on a shrunk basis ranged from 9.98 to 12.03 pounds per pound of gain. From 74 to 89 percent of the cows qualified in the “Premium White Fat” grades. Net profit ranged from $52 to $89 per ...


Texture Of Butters Made From Milks Differing In Indices Of Atherogenicity, Gerd Bobe, Shelly Zimmerman, Earl G. Hammond, A.E. Gene Freeman, Gary L. Lindberg, Donald C. Beitz Jan 2004

Texture Of Butters Made From Milks Differing In Indices Of Atherogenicity, Gerd Bobe, Shelly Zimmerman, Earl G. Hammond, A.E. Gene Freeman, Gary L. Lindberg, Donald C. Beitz

Animal Industry Report

The current study examined whether the phenotypic variation in milk fatty acid composition among cows fed the same diet was sufficient to produce butter with different textural properties. Butter samples from cows with a more unsaturated milk fatty acid composition had a lower index of atherogenicity and were more spreadable, softer, and less adhesive than were butter samples from cows with a more saturated milk fatty acid composition. Thus, selection of cows for milk fatty acid composition short-term by segregation and long-term by breeding programs can be used to produce butter that is more healthful and has a more favorable ...


Update From Animal Science Teaching Section, M. Douglas Kenealy Jan 2004

Update From Animal Science Teaching Section, M. Douglas Kenealy

Animal Industry Report

Placement rates for graduates of animal science remained strong in 2003. The sources of recruits and interests of students continue to shift. Community college transfers and urban high school students have become a larger segment of the animal science student population at Iowa State University (ISU). These students have different needs and interests in education. Transfer students may need to compact most of their animal science courses into two years at ISU, while Urban students tend to have a greater interest in courses in equine and companion animal studies. Times of change should be viewed positively as an opportunity for ...


Isolating Tender Muscles In The Pork Shoulder, Dennis N. Marple, Joseph G. Sebranek, Ben Huisinga Jan 2004

Isolating Tender Muscles In The Pork Shoulder, Dennis N. Marple, Joseph G. Sebranek, Ben Huisinga

Animal Industry Report

A procedure was developed to remove the Supraspinatus, Infraspinatus, Subscapularis, Triceps brachii (picnic cushion), Teres major and the flat portion of the Pectoralis profundi from pork shoulders separated from the carcass leaving either 2 or 4 ribs on the shoulder. The results of the study demonstrated that the composition of the residual picnic trim was not altered by removal of these key shoulder muscles in 4-rib shoulders.Therefore, processors could consider adding value to 4-rib pork shoulders without altering the composition of the picnic trim by isolating and merchandising specific shoulder muscles that have favorable eating qualities.


Selection For Disease Resistance: Why It Is Important And How It Can Be Accomplished, D. L. Nash, A.E. Gene Freeman Jan 2004

Selection For Disease Resistance: Why It Is Important And How It Can Be Accomplished, D. L. Nash, A.E. Gene Freeman

Animal Industry Report

No abstract provided.


Dairy Breeding Research Herd, A.E. Gene Freeman, Joe Detrick, David H. Kelley Jan 2004

Dairy Breeding Research Herd, A.E. Gene Freeman, Joe Detrick, David H. Kelley

Animal Industry Report

No abstract provided.


Adjusting Dairy Yield Records From 3 Times To 2 Time Milking Using A Random Regression Model, Nierlson Santos, A.E. Gene Freeman Jan 2004

Adjusting Dairy Yield Records From 3 Times To 2 Time Milking Using A Random Regression Model, Nierlson Santos, A.E. Gene Freeman

Animal Industry Report

No abstract provided.


Maximum Gain By Using Molecular Markers For Selection, Gamal-Abdel Azim, A.E. Gene Freeman Jan 2004

Maximum Gain By Using Molecular Markers For Selection, Gamal-Abdel Azim, A.E. Gene Freeman

Animal Industry Report

No abstract provided.


Milk Protein Genotypes Explain Variation Of Milk Protein Composition, Gerd Bobe, A.E. Gene Freeman, Gary L. Lindberg, Donald C. Beitz Jan 2004

Milk Protein Genotypes Explain Variation Of Milk Protein Composition, Gerd Bobe, A.E. Gene Freeman, Gary L. Lindberg, Donald C. Beitz

Animal Industry Report

The data demonstrate that cows with the genotypes κ- casein BB and β-lactoglobulin BB produce milk with a protein composition that is favorable for increased cheese yield. For proportions of αS1-casein, κ-casein, and β-lactoglobulin in total milk protein, κ-casein and β-lactoglobulin genotypes explained more than 50 and 25% of the heritability and repeatability estimates, respectively, and more than 14% of the phenotypic variance. Diet had only a minimal effect on milk protein composition. In conclusion, increasing cheese yield through modification of milk protein composition can be achieved most rapidly by selection for cows with κ-casein BB and β-lactoglobulin BB genotypes.


Lifetime Net Merit, A.E. Gene Freeman Jan 2004

Lifetime Net Merit, A.E. Gene Freeman

Animal Industry Report

No abstract provided.


Evaluating Potential Markers For Selection For Disease Resistance: The Health Traits Project, D. L. Nash, A.E. Gene Freeman Jan 2004

Evaluating Potential Markers For Selection For Disease Resistance: The Health Traits Project, D. L. Nash, A.E. Gene Freeman

Animal Industry Report

No abstract provided.


Properties Of Synemin, A Protein Important In Maintaining The Structural Integrity Of Muscle Cells, Richard M. Robson, Ted W. Huiatt Jan 2004

Properties Of Synemin, A Protein Important In Maintaining The Structural Integrity Of Muscle Cells, Richard M. Robson, Ted W. Huiatt

Animal Industry Report

Intermediate filaments (IFs), composed primarily of the protein desmin, link together the myofibrils in skeletal muscle. We have shown that the protein synemin is a novel IF protein and that it interacts with desmin. Together, these proteins are important in maintaining the structural integrity of muscle cells.


Effect Of Synovex Choice Implant On Performance And Carcass Traits Of Steer Calves, W. Darrell Busby, Daniel D. Loy, Dallas L. Maxwell Jan 2004

Effect Of Synovex Choice Implant On Performance And Carcass Traits Of Steer Calves, W. Darrell Busby, Daniel D. Loy, Dallas L. Maxwell

Animal Industry Report

A study was conducted at the Iowa State University Armstrong Research Farm to evaluate two intermediate dosage, combination implant systems. Two of four pens were implanted with Synovex Choice on day one and reimplanted on day 86 in the feedlot (Choice/Choice). The remaining two pens were implanted with Synovex-S on day one and reimplanted with Revalor-IS on day 86 (Syn/Rev). Steers were stepped up to a .60 Mcal/lb of DM finishing diet, and harvested in one of two groups based on real-time ultrasound evaluation. Total days on on feed were 166 for the Choice/Choice cattle and ...


State Of Iowa Feedlot Summary 15 Years Of Benchmarking Feedlot Performance, Daniel D. Loy Jan 2004

State Of Iowa Feedlot Summary 15 Years Of Benchmarking Feedlot Performance, Daniel D. Loy

Animal Industry Report

Fifteen years of closeout performance data was summarized to monitor trends in average daily gain and feed efficiency. Daily gain improved approximately 1% per year over the time period 1988–2002. Feed conversion improved approximately _ of 1% per year over the same time period.


Effect Of Postweaning Health On Feedlot Performance And Quality Grade, W. Darrell Busby, Daryl R. Strohbehn, Perry Beedle Iii, L. R. Corah Jan 2004

Effect Of Postweaning Health On Feedlot Performance And Quality Grade, W. Darrell Busby, Daryl R. Strohbehn, Perry Beedle Iii, L. R. Corah

Animal Industry Report

A total of 6,618 calves fed at eight Iowa feedlots were used to evaluate the effect of postweaning health on feedlot gain and carcass quality grade. The calves, representing 12 states, were consigned to the Iowa Tri-County Steer Carcass Futurity and were weighed upon arrival, after 35 days, at reimplant, and prior to harvest. A common dietary energy level was utilized at each feedlot. Calf health was classified as no treatment (NT; N=5,500), single treatment (ST; N=575), or two or more treatments (2T; N=543). The predominant cause of treatment was respiratory problems. Calves were sorted ...


Redesigning Beef Cattle To Have A More Healthful Fatty Acid Composition, Travis Knight, Jennifer A. Minick, Richard G. Tait Jr., Allen H. Trenkle, Doyle E. Wilson, Gene H. Rouse, Daryl R. Strohbehn, James M. Reecy, Donald C. Beitz Jan 2004

Redesigning Beef Cattle To Have A More Healthful Fatty Acid Composition, Travis Knight, Jennifer A. Minick, Richard G. Tait Jr., Allen H. Trenkle, Doyle E. Wilson, Gene H. Rouse, Daryl R. Strohbehn, James M. Reecy, Donald C. Beitz

Animal Industry Report

The objective was to determine the natural variability in beef fatty acid composition. We have used common gas chromatographic techniques to determine the fatty acid composition of phospholipids and triacylglycerols (TAGs) extracted from beef muscle (longissimus dorsi) from 800 sire-identified cattle originating from Iowa State University beef cattle breeding selection projects. Heritability of individual fatty acids and indexes of fatty acid desaturase and elongase systems were calculated by evaluating specific ratios of fatty acids (product/precursor). In general, we found that TAG composition is heritable, but phospholipid composition is not. The atherogenic index of TAGs as proposed by Ulbright and ...


Evaluation Of Wet And Dry Distillers Grains With Solubles For Finishing Holstein Steers, Allen H. Trenkle Jan 2004

Evaluation Of Wet And Dry Distillers Grains With Solubles For Finishing Holstein Steers, Allen H. Trenkle

Animal Industry Report

One hundred ninety-two 430 lb Holstein steers were allotted to 32 pens and fed eight diets in a 299-day trial to evaluate the responses of feeding wet or dry distillers grains (DGS) to growing and finishing dairy steers. The dry rolled corn, corn silage and chopped grass hay diets were supplemented with urea, soybean meal, 10, 20 & 40% dry DGS and 10, 20, & 40% wet DGS. During the initial 91 days of the trial, representing a growing period, steers fed soybean meal or dry DGS gained faster than those fed the diet with urea. Feed cost of gain was reduced ...