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Full-Text Articles in Life Sciences

Practices To Reduce Dust And Particulates From Livestock Operations, Wendy J. Powers Jul 2004

Practices To Reduce Dust And Particulates From Livestock Operations, Wendy J. Powers

Agriculture and Environment Extension Publications

Practices to control particulate and dust emissions associated with livestock production can be applied to animal housing and manure storage areas. This document provides an overview of various practices for each situation, highlights their advantages and disadvantages, and allows producers to make informed choices after evaluating production and economic aspects of their operations


Heritability And Repeatability Of Ultrasound Predicted Percentage Of Intramuscular Fat Measures In Angus Bulls And Heifers, Abebe T. Hassen, Doyle E. Wilson, Gene H. Rouse Jan 2004

Heritability And Repeatability Of Ultrasound Predicted Percentage Of Intramuscular Fat Measures In Angus Bulls And Heifers, Abebe T. Hassen, Doyle E. Wilson, Gene H. Rouse

Beef Research Report, 2003

The present study included repeated ultrasound-predicted percentage of intramuscular fat (UPFAT) measures from 675 Angus bulls and heifers collected over a three-year period between 1998 and 2000. Each year cattle were scanned four to six times for UPFAT and other ultrasound traits, starting at a minimum age of 28 weeks. The objective of the current study was to estimate variance components, heritability, and repeatability of UPFAT in young bulls and heifers. Heritability of UPFAT ranged from 0.32 at 28 weeks of age to a maximum of 0.53 at 63 weeks. Repeatability of UPFAT increased from a minimum of ...


Comparison Of Ultrasound And Carcass Measures To Predict Percentage Of Beef Retail Product From Four Primal Cuts—Final Report, Richard G. Tait Jr., Gene H. Rouse, Doyle E. Wilson Jan 2004

Comparison Of Ultrasound And Carcass Measures To Predict Percentage Of Beef Retail Product From Four Primal Cuts—Final Report, Richard G. Tait Jr., Gene H. Rouse, Doyle E. Wilson

Beef Research Report, 2003

The objective of this study was to determine how real-time ultrasound (RTU) measurements would compare with carcass measurements to predict the percentage of retail product from the four primals (PRP4P). Data were collected on market ready cattle (n=471). Traditional carcass measures collected were: 1) hot carcass weight (HCW), 2) 12–13th rib fat thickness (CFAT), 3) 12–13th rib ribeye area (CREA), and 4) percentage of kidney, pelvic, and heart fat (CKPH). Live animal ultrasound measures collected were: 1) scan weight (SCANWT), 2) 12–13th rib fat thickness (UFAT), 3) 12–13th rib ribeye area ...


Estimation Of Heritability And Repeatability Of Ultrasound Ribeye Area Measures Using Random Regression Models, Abebe T. Hassen, Doyle E. Wilson, Gene H. Rouse Jan 2004

Estimation Of Heritability And Repeatability Of Ultrasound Ribeye Area Measures Using Random Regression Models, Abebe T. Hassen, Doyle E. Wilson, Gene H. Rouse

Beef Research Report, 2003

The present study included 4,653 observations from 882 Angus bulls and heifers born during the spring of 1998 to 2001. Each year cattle were scanned four to eight times for ribeye area (UREA) and other ultrasound traits, starting at a minimum age of 27 weeks. The objective of the current study was to estimate variance components, heritability, and repeatability of UREA. Direct additive genetic variance increased from 7.11 to 19.4 cm4 as measurement age increased from 27 to 62 weeks. For the same time period direct permanent environmental variance increased from 14.7 to 26.6 cm ...


Body Composition Changes In Bulls From Weaning To Yearling Part I — Muscle, Waste Fat And Taste Fat Deposition, Gene H. Rouse, Doyle E. Wilson, Richard G. Tait Jr., Mike Anderson, Abebe T. Hassen Jan 2004

Body Composition Changes In Bulls From Weaning To Yearling Part I — Muscle, Waste Fat And Taste Fat Deposition, Gene H. Rouse, Doyle E. Wilson, Richard G. Tait Jr., Mike Anderson, Abebe T. Hassen

Beef Research Report, 2003

These results suggest how muscle, subcutaneous fat and intramuscular fat are deposited from weaning to yearling. How might these results be explained?

  • Tissue maturity —muscle matures earlier than fat in the growth process and has nutrient priority over fat when muscle is making maximum growth. Cattle normally make maximum growth, rate/day, when muscle is being deposited at the maximum rate. Why? Muscle has a much higher water content than fat, therefore, it requires less nutrients to deposit a pound of muscle then a pound of fat.
  • 10-1 Concept—during the fattening process, 10 pounds of waste fat (subcutaneous, seam ...


Genetic Analysis Of The Iowa Beef Tenderness And Carcass Evaluation Project, Jennifer A. Minick, Doyle E. Wilson, Daryl R. Strohbehn Jan 2004

Genetic Analysis Of The Iowa Beef Tenderness And Carcass Evaluation Project, Jennifer A. Minick, Doyle E. Wilson, Daryl R. Strohbehn

Beef Research Report, 2003

Steers from the Iowa Beef Tenderness and Carcass Evaluation Project were harvested and carcass data, including Warner-Bratzler shear force values, were collected. The heritability estimate of Warner-Bratzler shear force in this data set was 0.45, and the genetic correlation between tenderness and marbling score was -0.40. Steers with more marbling were more tender. Heritabilities for feed consumed per pound of gain and for feed consumed per day were 0.25 and 0.26 respectively. These traits were highly correlated with gain, but had no relationship to each other. The heritability of dressing percentage was 0.52. These preliminary ...


Estimating Heritability Of Percentage Of Intramuscular Fat And Ribeye Area Measures By Scan Session In Angus Bulls And Heifers, Abebe T. Hassen, Doyle E. Wilson, Gene H. Rouse Jan 2004

Estimating Heritability Of Percentage Of Intramuscular Fat And Ribeye Area Measures By Scan Session In Angus Bulls And Heifers, Abebe T. Hassen, Doyle E. Wilson, Gene H. Rouse

Beef Research Report, 2003

The present study included 3,066 ultrasound-predicted percentage of intramuscular fat (UPFAT) and 4,502 ultrasound ribeye area (UREA) measures of bulls and heifers from the Iowa State University beef cattle breeding project. Data were collected over a four-year period between 1998 and 2001. The objective of the current study was to estimate variance components and heritability of UPFAT and UREA. Data were analyzed based on single- and multiple-trait animal models. Heritability of UPFAT increased from a minimum of 0.36 at a mean age of 37 weeks to a maximum of 0.54 at a mean age of 54 ...


Integration Of Cool- And Warm-Season Grass Pasturing Systems Into Cattle Finishing Programs, M. Peter Hoffman, Roy E. Edler, Tsengeg Purevjav, Kenneth J. Moore, Wayne B. Roush Jan 2004

Integration Of Cool- And Warm-Season Grass Pasturing Systems Into Cattle Finishing Programs, M. Peter Hoffman, Roy E. Edler, Tsengeg Purevjav, Kenneth J. Moore, Wayne B. Roush

Iowa State Research Farm Progress Reports

Previously we reported on a study that demonstrated that fall-born steer calves pastured on bromegrass for either portions of or all of the grazing season and then finished in drylot, significantly outperformed calves placed directly into the feedlot in terms of profit/head at harvest time. Areas consisting of highly productive soils, interdispersed with highly erodable land, are well suited for this kind of production practice and in turn production systems of this nature are quite consistent with the concepts of sustainable agriculture. In an effort to capture more grazing potential, it was decided to incorporate warm-season grasses into the ...


Alternative Winter Farrowing Demonstration: A Progress Report, Peter J. Lammers, Mark S. Honeyman, Jay D. Harmon Jan 2004

Alternative Winter Farrowing Demonstration: A Progress Report, Peter J. Lammers, Mark S. Honeyman, Jay D. Harmon

Iowa State Research Farm Progress Reports

Development of systems enabling producers to capture premiums offered by niche markets is of great interest to many Iowa farmers. Of key concern is a winter farrowing system that is both economical to operate and meets the criteria of natural pork buyers. This report details the results from the alternative winter farrowing system demonstrated at the ISU Allee Demonstration Farm near Newell during the winter of 2002/2003.


Incidence Of Infectious Bovine Keratoconjunctivitis, Jose E. Rodriguez, James M. Reecy Jan 2004

Incidence Of Infectious Bovine Keratoconjunctivitis, Jose E. Rodriguez, James M. Reecy

Iowa State Research Farm Progress Reports

During 2003 an unusual number of calves showed signs of Infectious Bovine Keratoconjunctivitis (IBK), with 39.6% of the herd infected at the Rhodes Farm. Infectious Bovine Keratoconjunctivitis (IBK), commonly known as pink eye, is a contagious disease caused mostly by the bacteria Moraxella bovis, although other agents have been identified as a cause of IBK. Previous studies have shown that factors such as increased sunlight exposure, dust, tall grasses, and high populations of face flies (Musca autumnalis) facilitate M. bovis infection. Some of the symptoms associated with pink eye are reddening of the eyeball, swelling of the eyelid lining ...


Sow And Litter Performance For Individual Crate And Group Hoop Barn Gestation Housing Systems: Progress Report Ii, Peter J. Lammers, Mark S. Honeyman, John W. Mabry, C. Johnson Jan 2004

Sow And Litter Performance For Individual Crate And Group Hoop Barn Gestation Housing Systems: Progress Report Ii, Peter J. Lammers, Mark S. Honeyman, John W. Mabry, C. Johnson

Iowa State Research Farm Progress Reports

The effects of swine gestation housing on sow and litter performance were evaluated at the Iowa State University Lauren Christian Swine Research and Demonstration Farm near Atlantic, IA. The gestation systems were 1) individual gestation crates in a mechanically-ventilated, partially-slatted floor manure flush confinement building (CRATE); and 2) group pens in deep-bedded, naturally-ventilated hoop structures (HOOP). The HOOP sows were fed in individual feeding stalls. The sow genotypes were 1/4 Hampshire × 1/2 Yorkshire × 1/4 Landrace. Farrowing occurred every 2 weeks throughout the year.


Winter Grazing Of Corn Residues: Effects On Soil Properties And Subsequent Crop Yields From A Corn-Soybean Crop Rotation, W. Darrell Busby, James R. Russell, Douglas L. Karlen, L. James Secor, Brian Peterson, Carroll Olson, Shawn C. Shouse, Dallas L. Maxwell Jan 2004

Winter Grazing Of Corn Residues: Effects On Soil Properties And Subsequent Crop Yields From A Corn-Soybean Crop Rotation, W. Darrell Busby, James R. Russell, Douglas L. Karlen, L. James Secor, Brian Peterson, Carroll Olson, Shawn C. Shouse, Dallas L. Maxwell

Leopold Center Completed Grant Reports

Corn residues could be a good resource for winter cattle grazing. The study investigates whether winter grazing causes soil compaction and yield reduction in crops that are planted following grazing.


Complementary Grazing Systems For Beef Cattle Production, Kenneth J. Moore, Roger L. Hintz, Mary H. Wiedenhoeft, E. Charles Brummer, Stephen K. Barnhart, James R. Russell Jan 2004

Complementary Grazing Systems For Beef Cattle Production, Kenneth J. Moore, Roger L. Hintz, Mary H. Wiedenhoeft, E. Charles Brummer, Stephen K. Barnhart, James R. Russell

Leopold Center Completed Grant Reports

Pasture productivity in Iowa often is limited by the low yield of cool-season grasses in the summer. This project considers whether uneven seasonal distribution in pastures could be improved by including species that perform better under higher temperatures.


Triticale-Based Diets For Market Pigs In Deep-Bedded Hoop Barns: A Progress Report, Mark S. Honeyman, Zebblin M. Sullivan, Wayne B. Roush Jan 2004

Triticale-Based Diets For Market Pigs In Deep-Bedded Hoop Barns: A Progress Report, Mark S. Honeyman, Zebblin M. Sullivan, Wayne B. Roush

Iowa State Research Farm Progress Reports

Triticale (trit-ah-kay-lee) is a relatively new, synthetic small-grain crop produced by crossing Durum wheat with rye. Triticale was developed to combine the high crude protein and digestible energy of wheat with the high yields and protein quality of rye. Triticale has the ability to grow in acidic soils and extreme climates, and has larger yields than rye, making it a practical and economical feedstuff. Triticale is not a major crop in the United States; therefore, it has not been widely fed to livestock.


Real-Time Ultrasound And Performance Measures To Assist In Feedlot Cattle Sorting For Marketing Decisions, Richard G. Tait Jr., Gene H. Rouse, P. B. Wall, W. Darrell Busby, D. Maxwell Jan 2004

Real-Time Ultrasound And Performance Measures To Assist In Feedlot Cattle Sorting For Marketing Decisions, Richard G. Tait Jr., Gene H. Rouse, P. B. Wall, W. Darrell Busby, D. Maxwell

Iowa State Research Farm Progress Reports

Decision support systems are necessary for producers to make informed decisions about how to manage cattle for marketing decisions. This report is designed to describe the protocol used for Iowa State University research cattle to determine when cattle should be harvested.


Body Composition Changes In Bulls From Weaning Age To Yearling Age: Muscle Fat Deposition, Gene H. Rouse, Richard G. Tait Jr., M. Anderson, Abebe Hassen Jan 2004

Body Composition Changes In Bulls From Weaning Age To Yearling Age: Muscle Fat Deposition, Gene H. Rouse, Richard G. Tait Jr., M. Anderson, Abebe Hassen

Iowa State Research Farm Progress Reports

With the advent of real-time ultrasound, repeated measures of body composition changes, such as fat cover, rib eye area, and percentage intramuscular fat have greatly added to our understanding of beef cattle growth and development.


Impacts Of Cattle Grazing Management On Sediment And Phosphorus Loads In Surface Waters, Mathew M. Haan, James R. Russell, Wendy Powers, John Kovar, Richard C. Schultz, Steven K. Mickelson Jan 2004

Impacts Of Cattle Grazing Management On Sediment And Phosphorus Loads In Surface Waters, Mathew M. Haan, James R. Russell, Wendy Powers, John Kovar, Richard C. Schultz, Steven K. Mickelson

Iowa State Research Farm Progress Reports

The amounts of sediment and phosphorus (P) in water runoff from agricultural lands are of concern because of the potential for siltation and eutrophication of surface waters. There is limited information about the total sediment and P loads in runoff from pastureland in the Midwest. Because vegetation limits soil disruption caused by the impact of raindrops and forage roots hold soil particles, pastures grazed using suitable management practices should maintain water infiltration and minimize sediment and P losses in water runoff. Once sediment and P have been dislodged from the landscape, vegetative buffers can be an effective tool for reducing ...