LIVIVO - Das Suchportal für Lebenswissenschaften

switch to English language
Erweiterte Suche

Suchergebnis

Treffer 1 - 9 von insgesamt 9

Suchoptionen

  1. Artikel: Soil health changes following transition from an annual cropping to perennial management‐intensive grazing agroecosystem

    Shawver, Casey J. / Ippolito, James A. / Brummer, Joe E. / Ahola, Jason K. / Rhoades, Ryan D.

    Agrosystems, geosciences & environment. 2021, v. 4, no. 2

    2021  

    Abstract: Management‐intensive grazing (MiG) on irrigated, perennial pastures has steadily increased in the western United States due to pressure for reducing public lands grazing, overall declining land available for pasture, and decreasing commodity prices. ... ...

    Abstract Management‐intensive grazing (MiG) on irrigated, perennial pastures has steadily increased in the western United States due to pressure for reducing public lands grazing, overall declining land available for pasture, and decreasing commodity prices. However, there are still many unknowns regarding MiG and its environmental impact, especially with regards to soil health. Over a 2‐yr period, a study evaluating the change in soil health under a full‐scale, 82‐ha pivot‐irrigated perennial pasture system grazed with ∼230 animal units (AUs) using MiG. Soil analysis included 11 soil characteristics aggregated into the Soil Management Assessment Framework (SMAF), which outputs results for soil biological, physical, nutrient, chemical, and overall soil health indices (SHIs). Over time, positive impacts were observed in the chemical and biological SHI due to decreases in salt content and increases in microbial and enzymatic activities. Soil organic C (SOC) remained unchanged, yet positive biological SHI changes are potential precursors to future SOC increases. The chemical and nutrient SHI increased in the soil surface due to reductions in salt content in conjunction with increased plant‐available soil P, as a result of salt leaching via irrigation and pre‐study inorganic P fertilizer application in conjunction with manure deposition due to MiG, respectively. Finally, a negative impact was also observed in the physical SHI, driven primarily by increasing bulk density due to hoof pressure from cattle grazing. If managed correctly, compaction issues can be avoided, with MiG systems having potential success in supporting grazing while promoting soil health for environmental and economic sustainability.
    Schlagwörter agroecosystems ; bulk density ; cattle ; economic sustainability ; environment ; environmental impact ; fertilizer application ; irrigation ; pastures ; phosphorus fertilizers ; salt content ; soil ; soil analysis ; soil organic carbon ; soil quality
    Sprache Englisch
    Erscheinungsort John Wiley & Sons, Ltd
    Dokumenttyp Artikel
    Anmerkung JOURNAL ARTICLE
    ISSN 2639-6696
    DOI 10.1002/agg2.20181
    Datenquelle NAL Katalog (AGRICOLA)

    Zusatzmaterialien

    Kategorien

    Über subito bestellen

    Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.

    Fernleihe an ZB MED

    Sie können sich den gewünschten Titel als lokale Nutzerin oder lokaler Nutzer von ZB MED direkt an den Standort Köln schicken lassen.

  2. Artikel ; Online: Evaluation of performance and carcass traits for a five-cohort All Heifer, No Cow beef production system demonstration herd.

    Harrison, Meredith A / Arce-Cordero, Jose A / Seidel, George E / Archibeque, Shawn L / Whittier, Jack C / Rhoades, Ryan D / Ahola, Jason K

    Translational animal science

    2020  Band 4, Heft 4, Seite(n) txaa191

    Abstract: The All Heifer, No Cow (AHNC) beef production system is an alternative to conventional cow/calf production that involves insemination of nulliparous heifers with sexed semen to produce female calves that are early weaned at 3 mo of age. Dams are finished ...

    Abstract The All Heifer, No Cow (AHNC) beef production system is an alternative to conventional cow/calf production that involves insemination of nulliparous heifers with sexed semen to produce female calves that are early weaned at 3 mo of age. Dams are finished on a high-concentrate diet and harvested before reaching 30 mo of age. Objectives of this research were to document reproductive, feedyard, calf, and carcass performance of an AHNC herd; evaluate effects of carcass maturity on carcass quality; and determine if performance of initial cohorts (i.e., cohorts 1 and 2) differed from sustaining cohorts (i.e., cohorts 3-5). A total of 272 heifers were enrolled in the AHNC system via five annual cohorts. The system was initiated with 51 yearling, Angus-based heifers, and a replicate set (
    Sprache Englisch
    Erscheinungsdatum 2020-10-27
    Erscheinungsland England
    Dokumenttyp Journal Article
    ISSN 2573-2102
    ISSN (online) 2573-2102
    DOI 10.1093/tas/txaa191
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

    Über subito bestellen

    Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.

    Fernleihe an ZB MED

    Sie können sich den gewünschten Titel als lokale Nutzerin oder lokaler Nutzer von ZB MED direkt an den Standort Köln schicken lassen.

  3. Artikel ; Online: Evaluation of biological and economic efficiency of the All Heifer, No Cow beef production system using a system dynamics model based on 6 yr of demonstration herd data.

    Harrison, Meredith A / Sheehan, John J / Seidel, George E / Mooney, Dan F / Rhoades, Ryan D / Ahola, Jason K

    Journal of animal science

    2020  Band 99, Heft 1

    Abstract: Alternative management strategies with no cows and all heifers may improve biological and economic efficiency of beef production. The All Heifer, No Cow (AHNC) beef production system involves insemination of nulliparous heifers with female sex-selected ... ...

    Abstract Alternative management strategies with no cows and all heifers may improve biological and economic efficiency of beef production. The All Heifer, No Cow (AHNC) beef production system involves insemination of nulliparous heifers with female sex-selected semen (FSS) to produce primarily female calves that are early weaned at 3 mo of age. Dams are finished on a high concentrate diet and harvested before 30 mo of age. The objectives of this research were to: 1) build a dynamic model of an AHNC beef production system to quantify system biological and economic efficiency; 2) compare effects of utilizing FSS vs. conventional semen on biological and economic efficiency; 3) evaluate what-if scenarios to determine the effects on biological and economic efficiency of changing variables ±5%, 10%, 15%, and 20% from initial observed values; and 4) evaluate the effects on biological and economic efficiency of changing variables ±10% from initial observed values. A model was built over a 21-yr horizon using Stella Architect. Biological parameter values in the model were based on the 6 yr of data collected from the management of an AHNC demonstration herd. In the model animal, total digestible nutrients (TDN) intake, hot carcass weight (HCW), and age at harvest were randomized. Feed, animal, and carcass prices included in the model were based on 10 yr of historical U.S. price data. Key response variables were biological and economic efficiency (mean ± SD). Biological efficiency was defined as the ratio of output (kilograms of HCW produced) to input (lifetime kilograms of feed TDN consumed), and economic efficiency was measured using a benefit-cost ratio (BCR) and unit variable cost (UVC). Over 40 simulation runs, the predicted mean biological efficiency was 0.0714 ± 0.0008. Economic efficiency was 0.95 ± 0.02 and US $445.41 ± 0.06 for BCR and UVC, respectively. Biological and economic efficiency was improved in the conventional semen scenario; biological efficiency was 0.0738 ± 0.0008, and BCR and UVC were 0.99 ± 0.04 and US $407.24 ± 0.006, respectively. Under this parameterization and market conditions, the AHNC beef production system failed to achieve profitability under any scenario that was evaluated. However, this review did not account for the potential increased genetic benefit from a decreased generation interval and the reduction in feed energy in comparison to a conventional cow/calf system.
    Mesh-Begriff(e) Animal Husbandry ; Animals ; Cattle ; Diet/veterinary ; Eating ; Energy Intake ; Female ; Semen ; Weaning
    Sprache Englisch
    Erscheinungsdatum 2020-12-17
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Review
    ZDB-ID 390959-1
    ISSN 1525-3163 ; 0021-8812
    ISSN (online) 1525-3163
    ISSN 0021-8812
    DOI 10.1093/jas/skaa405
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

    Verfügbar in ZB MED Köln/Königswinter

    Zs.A 1312: Hefte anzeigen Standort:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

    Über subito bestellen

    Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.

  4. Artikel: A Systems Thinking Approach to Ranching: Finding Leverage to Mitigate Drought

    Rhoades, Ryan D / Clay P. Mathis / Kimberly C. McCuistion

    The Society for Range Management Rangelands. 2014 Dec., v. 36, no. 6

    2014  

    Abstract: Drought is an adaptive challenge where management strategies and practices that work today might not work tomorrow. Adaptive challenges facing management may require thinking systemically to determine leverage points. Systems thinking can be an effective ...

    Abstract Drought is an adaptive challenge where management strategies and practices that work today might not work tomorrow. Adaptive challenges facing management may require thinking systemically to determine leverage points. Systems thinking can be an effective way to see the big picture, deal with complex situations, and create effective long-term management alternatives for the ranch. Successful management alternatives will provide flexibility to protect the core business (i.e., cow herd), be enterprise-diverse to spread risk, and allow management for the good of the whole, not simplyto maximize the pieces. It is important to evaluate your own ranching system to identify the appropriate enterprises or practices, there is no best mix.
    Schlagwörter cows ; drought ; herds ; ranching ; range management ; rangelands ; risk
    Sprache Englisch
    Erscheinungsverlauf 2014-12
    Umfang p. 2-6.
    Erscheinungsort Elsevier Inc.
    Dokumenttyp Artikel
    ZDB-ID 743075-9
    ISSN 1551-501X ; 0190-0528
    ISSN (online) 1551-501X
    ISSN 0190-0528
    DOI 10.2111/RANGELANDS-D-14-00017
    Datenquelle NAL Katalog (AGRICOLA)

    Zusatzmaterialien

    Kategorien

    Verfügbar in ZB MED Bonn

    Z 4564: Hefte anzeigen

    Über subito bestellen

    Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.

    Fernleihe an ZB MED

    Sie können sich den gewünschten Titel als lokale Nutzerin oder lokaler Nutzer von ZB MED direkt an den Standort Köln schicken lassen.

  5. Artikel: Employee Management on Large Ranches

    Rhoades, Ryan D / Clay P. Mathis / J.J. Livsey / Kim C. McCuistion

    The Society for Range Management Rangelands. 2013 Apr., v. 35, no. 2

    2013  

    Abstract: Managing people is a vital component of managing a large ranch. Employee management practices have an effect on turnover in any organization, and our study specifically examined management practices on ranches. Our study describes the state of employee ... ...

    Abstract Managing people is a vital component of managing a large ranch. Employee management practices have an effect on turnover in any organization, and our study specifically examined management practices on ranches. Our study describes the state of employee management on large ranches and provides useful and practical information that may help ranch managers build their personnel management skills. Managers could potentially enhance employee performance by reviewing their operations management procedures and incentive structures and adjusting them as needed.
    Schlagwörter human resources ; human resources management ; managers ; ranching
    Sprache Englisch
    Erscheinungsverlauf 2013-04
    Umfang p. 2-11.
    Erscheinungsort Elsevier Inc.
    Dokumenttyp Artikel
    ZDB-ID 743075-9
    ISSN 1551-501X ; 0190-0528
    ISSN (online) 1551-501X
    ISSN 0190-0528
    DOI 10.2111/RANGELANDS-D-12-00076.1
    Datenquelle NAL Katalog (AGRICOLA)

    Zusatzmaterialien

    Kategorien

    Verfügbar in ZB MED Bonn

    Z 4564: Hefte anzeigen

    Über subito bestellen

    Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.

    Fernleihe an ZB MED

    Sie können sich den gewünschten Titel als lokale Nutzerin oder lokaler Nutzer von ZB MED direkt an den Standort Köln schicken lassen.

  6. Konferenzbeitrag ; Online: Consumer Preferences in Purchasing Beef and the Values they Attribute to Branded Beef Products

    Hanagriff, Roger D. / Rhoades, Ryan D. / Wilmeth, Doug

    2008  

    Abstract: There have been significant changes in consumer demand at the retail counter, such as health, convenience, palatability preferences, and safety concerns. Branded programs offer a means for satisfying consumer demand for high quality and differentiated ... ...

    Abstract There have been significant changes in consumer demand at the retail counter, such as health, convenience, palatability preferences, and safety concerns. Branded programs offer a means for satisfying consumer demand for high quality and differentiated beef products. To help answer the question of who is purchasing branded beef market and why, an online survey was sent to interested beef consumers to determine their preferences of purchasing, as well as values they attribute to certain product characteristics. The total sample response from 13,000 contacted consumers was 502 responses, which according to Kreiche and Morgan, 1970 is a valid sample size. Decision variables ranked moderate and always important include guaranteed tender and satisfaction, low price, and low fat or lean. Differences in the strength of the decision values, such as always important, moderately important to seldom important were found with gender, purchasing frequency product differences. Results provide a better understanding of consumer decisions to buy branded beef and may assist producers with advertising decisions.
    Schlagwörter Beef demand ; consumer beef demand ; demand preferences for beef ; Agribusiness ; Agricultural and Food Policy ; Consumer/Household Economics
    Thema/Rubrik (Code) 303
    Sprache Englisch
    Erscheinungsdatum 2008-01-16
    Erscheinungsland us
    Dokumenttyp Konferenzbeitrag ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

    Volltext online

    Zusatzmaterialien

    Kategorien

    Fernleihe an ZB MED

    Sie können sich den gewünschten Titel als lokale Nutzerin oder lokaler Nutzer von ZB MED direkt an den Standort Köln schicken lassen.

  7. Artikel: Employee Management on Large Ranches

    Rhoades, Ryan D. / Livsey, J. J. / McCuistion, Kim C. / Mathis, Clay P.

    Rangelands

    2013  Band 35, Heft 2, Seite(n) 2

    Sprache Englisch
    Dokumenttyp Artikel
    ZDB-ID 743075-9
    ISSN 0190-0528
    Datenquelle Current Contents Ernährung, Umwelt, Agrar

    Zusatzmaterialien

    Kategorien

    Verfügbar in ZB MED Bonn

    Z 4564: Hefte anzeigen

    Über subito bestellen

    Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.

    Fernleihe an ZB MED

    Sie können sich den gewünschten Titel als lokale Nutzerin oder lokaler Nutzer von ZB MED direkt an den Standort Köln schicken lassen.

  8. Artikel: Postmortem regulation of glycolysis by 6-phosphofructokinase in bovine M. Sternocephalicus pars mandibularis.

    Rhoades, Ryan D / King, D Andy / Jenschke, Blaine E / Behrends, Jason M / Hively, Teresa S / Smith, Stephen B

    Meat science

    2005  Band 70, Heft 4, Seite(n) 621–626

    Abstract: This experiment addressed the hypothesis that 6-phosphofructokinase (6-PFK) regulates glycolysis in postmortem in M. sternocephalicus pars mandibularis. In two separate experiments, muscle samples were excised from randomly-selected steers that would ... ...

    Abstract This experiment addressed the hypothesis that 6-phosphofructokinase (6-PFK) regulates glycolysis in postmortem in M. sternocephalicus pars mandibularis. In two separate experiments, muscle samples were excised from randomly-selected steers that would typically be found on a commercial slaughter floor. In the first experiment, two samples were obtained from each of 6 steers immediately post-exsanguination; one sample was immersed immediately in liquid nitrogen and the other was stored at 4°C for 4 d, to compare 6-PFK enzyme activity and glycolytic intermediate concentrations between fresh and d 4 postmortem samples. The greatest activity of 6-PFK was measured in fresh muscle extracts at pH 7.4, whereas little activity was detectable at pH 7.0. 6-PFK activity measured at pH 7.4 in d 4 samples also was barely detectable. Hill coefficient values for 6-PFK in fresh samples measured at pH 7.4 or 7.0, and d 4 samples measured at pH 7.4 were 2.9, 0.8, and 0.7, respectively, indicating loss of cooperativity with both lowered pH during assay and with time postmortem. Glycogen concentrations decreased 45% from d 0 to d 4, to 39.6μmol glycogen/g muscle. Muscle concentrations of free glucose increased (P<0.001) from 0.84μmol/g at d 0 to 6.54μmol/g at d 4. Fructose-6-phosphate and glucose-6-phosphate increased (P<0.001) from d 0 to d 4 (2.8-fold and 4.7-fold, respectively). Lactate began accumulating immediately (3.33μmol/g) and was elevated to 45.9μmol/g by d 4. In the second experiment, conversion of [U-(14)C]glucose to lactate, glycogen, and CO(2) was measured in vitro at pH 7.4 and 7.0 in fresh M. sternocephalicus pars mandibularis strips from four steers. Total [U-(14)C]glucose was less in muscle strips incubated at pH 7.0 than in those incubated at pH 7.4 (55.5 vs. 123nmol glucose utilized per 100mg muscle per h; P=0.04), due primarily to a reduction in glucose conversion to lactate. The conversion of glucose to glycogen or CO(2) in vitro was unaffected by media pH. These results suggest that the postmortem decline in pH in M. sternocephalicus pars mandibularis ultimately inactivates 6-PFK; this occurs prior to the depletion of glycogen reserves.
    Sprache Englisch
    Erscheinungsdatum 2005-08
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 753319-6
    ISSN 1873-4138 ; 0309-1740
    ISSN (online) 1873-4138
    ISSN 0309-1740
    DOI 10.1016/j.meatsci.2005.01.024
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Volltext online

    Zusatzmaterialien

    Kategorien

    Verfügbar in ZB MED Bonn

    Z 4037: Hefte anzeigen

    Über subito bestellen

    Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.

    Fernleihe an ZB MED

    Sie können sich den gewünschten Titel als lokale Nutzerin oder lokaler Nutzer von ZB MED direkt an den Standort Köln schicken lassen.

  9. Artikel: Consumer Preferences in Purchasing Beef and the Values they Attribute to Branded Beef Products

    Hanagriff, Roger D. / Rhoades, Ryan D. / Wilmeth, Doug

    Abstract: There have been significant changes in consumer demand at the retail counter, such as health, convenience, palatability preferences, and safety concerns. Branded programs offer a means for satisfying consumer demand for high quality and differentiated ... ...

    Abstract There have been significant changes in consumer demand at the retail counter, such as health, convenience, palatability preferences, and safety concerns. Branded programs offer a means for satisfying consumer demand for high quality and differentiated beef products. To help answer the question of who is purchasing branded beef market and why, an online survey was sent to interested beef consumers to determine their preferences of purchasing, as well as values they attribute to certain product characteristics. The total sample response from 13,000 contacted consumers was 502 responses, which according to Kreiche and Morgan, 1970 is a valid sample size. Decision variables ranked moderate and always important include guaranteed tender and satisfaction, low price, and low fat or lean. Differences in the strength of the decision values, such as always important, moderately important to seldom important were found with gender, purchasing frequency product differences. Results provide a better understanding of consumer decisions to buy branded beef and may assist producers with advertising decisions.
    Sprache Englisch
    Dokumenttyp Artikel
    Datenquelle AGRIS - International Information System for the Agricultural Sciences and Technology

    Zusatzmaterialien

    Kategorien

    Fernleihe an ZB MED

    Sie können sich den gewünschten Titel als lokale Nutzerin oder lokaler Nutzer von ZB MED direkt an den Standort Köln schicken lassen.

Zum Seitenanfang