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Differentially Expressed Genes In Blood From Young Pigs Between Two Swine Lines Divergently Selected For Feed Efficiency: Potential Biomarkers For Improving Feed Efficiency, Haibo Liu, Yet T. Nguyen, Daniel S. Nettleton, Jack C. M. Dekkers, Christopher K. Tuggle

Dan Nettleton

The goal of this study was to find potential gene expression biomarkers in blood of piglets that can be used to predict pigs’ future feed efficiency. Using RNA-seq technology, we found 453 genes were differentially expressed (false discovery rate (FDR) ≤ 0.05) in the blood of two Yorkshire lines of pigs divergently selected for feed efficiency (FE) based on residual feed intake (RFI). Genes involved in several biosynthetic processes were overrepresented among genes more highly expressed in the low RFI line compared to the high RFI line. Weighted gene co-expression network analysis (WGCNA) also revealed genes involved in some of …

Winter Grazing Management, Stephen K. Barnhart, James R. Russell, Douglas L. Karlen, Michael J. Tidman

Douglas L Karlen

Why winter grazing? Beef cow herd and sheep flock records show that winter feeding costs are livestock producers' single largest production expense. Managing through winter weather while keeping feeding costs low is an essential part of maintaining a profitable operation. Iowa's climate generally allows forage growth only during a 7-to-8 month period. Extending the grazing of this forage--even an extra 3 or 4 weeks in late autumn and winter--is an economical way to maintain or increase livestock profitability. Some producers extend the grazing season by using stockpiled forage, whereas others use crop residue, and many combine the use of stockpiled …

Effects Of Corn Crop Residue Grazing On Soil Physical Properties And Subsequent Soybean Production In A Corn-Soybean Crop Rotation (A Progress Report), Justin Clark, James R. Russell, Douglas Karlen, Darrell Busby, L. James Secor, Brian Peterson, Larry Pellack, Carroll Olsen, Shawn C. Shouse

Douglas L Karlen

The highest cost to beef cow-calf producers is the feeding of stored feeds in winter months. To lower feed costs, many producers will try to extend the grazing season into the winter. The primary resource for winter grazing in the Midwest is corn crop residues. On the average, corn crop residue grazing will reduce the amount of hay needed to maintain cows by approximately one-half ton per acre grazed over the winter. Although crop residue grazing is quite effective in reducing feed costs, some producers are concerned that corn residue grazing will have an adverse effect on soybean yields the …

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

Douglas L Karlen

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.

Effects Of Corn Crop Residue Grazing On Soil Physical Properties And Subsequent Soybean Production In A Corn–Soybean Crop Rotation, Justin Clark, James R. Russell, Douglas Karlen, W. Darrell Busby, Brian Peterson, Larry Pellack, Dallas L. Maxwell

Douglas L Karlen

For three years beginning in 1999, a 96-acre field near Atlantic, Iowa was used to study the effects of corn residue grazing by beef cows on soil characteristics and soybean yields in subsequent years. Each winter, cows were allowed to graze corn crop residues inside selected paddocks in four sub-fields over five monthly periods. To compare the effects of grazing, one paddock was left as an ungrazed control. At the end of grazing in the spring, soil bulk density, moisture content, and penetration resistance were measured inside and 15 ft outside twelve grazing exclosures in each paddock. Soil surface roughness, …

Beef Cattle Breeding Project Progress Report: Growth-Trait Epds For 1998- And 1999-Born Calves, Abebe T. Hassen, Doyle E. Wilson, Gene H. Rouse, Richard G. Tait Jr.

Richard G. Tait Jr.

The Iowa State University beef cattle breeding project was designed to develop two selection lines of beef cattle for use as a research base to answer questions that influence genetic improvement. The project was started in 1996 and is being conducted at the Rhodes (central Iowa) and McNay (southern Iowa) research and demonstration farms.

Comparison Of Ultrasound And Carcass Measures To Predict The Percentage Of Lean Beef From Four Primal Cuts – A Progress Report, Richard G. Tait Jr., Gene H. Rouse, Doyle E. Wilson

Richard G. Tait Jr.

The objective of this study was to determine how real-time ultrasound (RTU) measurements would compare with carcass measurements to predict the percentage of lean from the four primals (PERL4P). Data were collected on market ready cattle (n=490). 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 (KPH).

Beef Cattle Breeding Project Progress Report: Body Composition Epds Determined From Ultrasound Measures, Doyle E. Wilson, Abebe T. Hassen, Gene H. Rouse, Richard G. Tait Jr.

Richard G. Tait Jr.

The Iowa State University beef cattle breeding project was initiated in 1996, and is being conducted at the Rhodes and McNay Research and Demonstration Farms. The project uses the field data of the American Angus Association (AAA) along with the research resource cattle of the farms to study questions that will enhance the genetic investigations using the field data.

Beef Cattle Breeding Project Progress Report: Growth Trait Epds For 1998-, 1999-, And 2000-Born Calves, Abebe T. Hassen, D. E. Wilson, Gene H. Rouse, Richard G. Tait Jr.

Richard G. Tait Jr.

The Iowa State University beef cattle breeding project was designed to develop two selection lines of beef cattle for use as a research base to answer questions that influence genetic improvement. The project was started in 1996 and is being conducted at Rhodes (central Iowa) and McNay (southern Iowa) research and demonstration farms.

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

Richard G. Tait Jr.

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 and internal …

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

Richard G. Tait Jr.

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.

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

Richard G. Tait Jr.

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 (UREA), 4) subcutaneous fat thickness over the termination of …

Characterizing Overall Response To Two-Shot Vaccination For Bvdv Type 2 In Angus Weanling Calves, Richard Tait, Erika Downey, Mary Mayes, Julia Ridpath, Dorian Garrick, James Reecy

Richard G. Tait Jr.

Vaccination is a management strategy utilized to help reduce prevalence of bovine respiratory disease in feedlots. However, not all animals respond similarly to vaccinations. It is believed that an animal’s genetics control part of the ability to respond to a vaccination protocol. In order to evaluate the genetic control of a new trait such as response to vaccination, it is important to understand the non-genetic factors that affect an animal’s response to vaccination. The objective of this study was to characterize the non-genetic factors affecting overall response to a two-shot vaccination for bovine viral diarrhea virus type 2 (BVDV2) in …

Effects Of Calf Age And Dam Age On Circulating Bvdv Ii Antibody Levels Prior To Vaccination In Angus Weanling Calves, Erika Diane Downey, Richard G. Tait Jr., Mary Sue Mayes, Dorian J. Garrick, Julia Ridpath, James M. Reecy

Richard G. Tait Jr.

Newborn calves passively acquire antibodies from their dams via consumption of colostrum immediately after birth. Colostrum quality and quantity may differ by dam age affecting the amount of circulating maternally derived antibodies. The objective of this study was to evaluate if there are differences in calf titers of maternal antibodies based on age of dam and age of calf. This knowledge is important for determining vaccination strategies because passively acquired antibodies for bovine viral diarrhea virus I and II (BVDV) have been shown to block the ability of calves to develop their own specific immune response to BVDV.

Correlations Between Carcass Traits And Mineral Concentrations In Angus Beef Raised In Iowa, Richard G. Tait Jr., Qing Duan, Qi Liu, Mary Sue Mayes, Donald C. Beitz, James M. Reecy

Richard G. Tait Jr.

Beef is a nutritious food that is known to have high bioavailability for several minerals such as iron and zinc. Although beef is typically high in these nutrients, there is much animalto-animal variation in mineral contents. The objective of this study is to report the relationship between traditional carcass traits and mineral concentrations within the longissimus dorsi.

Whole Genome Analysis Of Pinkeye Scores In Angus Cattle, Kadir Kizilkaya, Richard G. Tait Jr., Dorian J. Garrick, Rohan L. Fernando, James M. Reecy

Richard G. Tait Jr.

Infectious Bovine Keratoconjunctivitis (IBK), known as pinkeye, is a common infectious disease affecting the eyes of cattle. It is characterized by excessive tearing, inflammation of the conjunctiva, and ulceration of the cornea. Although pinkeye is non-fatal, it has a marked economic impact on the cattle industry, due to the decreased performance of infected individuals. Genetic effects on the susceptibility of IBK have been studied and Hereford, Jersey, and Holstein breeds were found to be more susceptible to IBK than Bos Indicus breeds. The objectives of our study were: 1) to estimate genetic parameters of IBK scored in different categories by …

Ibk (Pinkeye) In Black Angus Cattle, Jose E. Rodriguez, Abebe Hassen, Richard G. Tait Jr., James M. Reecy

Richard G. Tait Jr.

Infectious Bovine Keratoconjunctivitis (IBK), commonly known as pinkeye, is a contagious bacterial disease that affects cattle worldwide. IBK is characterized by excessive tearing, inflammation of the conjunctiva, and ulceration of the cornea. In severe cases, perforation of the cornea may occur, leading to permanent blindness. The incidence rates reported in the ISU beef herd range from 30–52% in the last four years(Figure 1). As a result of the economic impact of pinkeye in the cattle industry, estimated at $150 million/year, the lack of effective treatments against the disease and the increased demand for‘organic’ products, research in the area of disease …

Factors Influencing Reproductive Performance Of Cows From Different Nguni Ecotypes In Southern Mozambique, S Maciel, O Mwai, Joshua O. Amimo, S Moyo, M Scholtz, F Neser, M Martins

Joshua O Amimo

No abstract provided.

An Assessment Of The Efficiency Of The Dairy Bull Dam Selection Methodology In Kenya, J Ombura, J W. Wakhungu, R O. Mosi, Joshua O. Amimo

Joshua O Amimo

No abstract provided.

Phenotypic And Genetic Parameters Of Reproductive Traits For Ayrshire Cattle On Large-Scale Farms In Kenya, Joshua O. Amimo

Joshua O Amimo

No abstract provided.