| Title |
Investigators | Department | Objectives | Approach Keywords | Progress Reports | Impact Statements | Publications | |
Project * COL00607 | |
| Title | Livestock Management Systems |
| Investigator(s) | Enns, RM; Whittier, JC; Field, TG; Garrick, DJ; Umberger, WJ; |
| Department | Animal Science |
| Objectives | The primary goal of this project is to develop flexible, user-friendly, and accurate decision support tools, such as simulation models, that will help beef cattle producers (1) make strategic management decisions and (2) evaluate the system-wide, performance and economic impacts of those decisions. Specific objectives include: 1. development of criteria for optimal tool structures including user interfaces; biological, and economic components ; 2. development/improvement of methods for integration of costs/incomes of production, genetic prediction technologies, and underlying biological systems (such as interactions of range, nutrition, reproduction, and selection); 3. identification of performance and economic data critical to proper model parameterization; 4. improvement of underlying biological models; 5. validation/parameterization of deliverable products. |
| Approach | We will use a two-pronged strategy first focusing on short-term deliverables that begin to incorporate a systems perspective. The ultimate long-term goal is to combine these into a flexible, user-friendly system that allows producers at all segments of the industry to evaluate management decisions and the local and system-wide impacts of those decisions. This approach allows production of tools that are both immediately deliverable and usable and concurrently contribute to the long-term goal. The first deliverables will focus on the cow/calf sector of the beef industry, followed by the feedlot and stocker sectors. We will incorporate user input/feedback to design interfaces for all models to increase industry adoption. The economic models will incorporate appropriate stochastic methods for generating costs and prices based either on historical information or on user supplied data , enabling risk analyses. Genetic prediction technologies such as currently available Expected Progeny Differences (EPD) and EPD currently under development will be integrated into the models to allow users to benchmark the genetic potential of their herds and to understand the interactions of genetics and environment/management on the production system . The final system will use object-oriented design procedures to modularize components and increase ease of improvement of the system. With this design, scientists (not only at Colorado State University) can download a specific class (i.e. component) of the model, make revisions based on current research and "plug" that component back into the system with no revision of the other components required. The same is true of the graphical user interface designers. Using the CSU Beef Alliance, data points critical to the parameterization will be identified and communicated to the industry as required for proper , operation-specific use of these models. Validation/parameterization of the models and their components will comprise data from both in-house resources (e.g. CSU Beef Alliance), experience with users, and interaction with clients of the CSU Center for Genetic Evaluation of Livestock--currently numbering over 15 breed associations. Models will be delivered with baseline values included. Producers will then have the option of "burrowing" to whatever level of model complexity that they are comfortable with during the parameterization procedures. For instance, producers could use national pricing data or input values for their local region-specific conditions. This framework has been used successfully in international dairy industries. |
| Keywords | livestock management, management systems, beef cattle, improvement, production management, decision making, simulation, computer analysis, livestock production , animal breeding, expected progeny differences, economics, profitability, genetic merit, sire selection, stochastic processes, risk, predictive models, validation |
| Progress Reports | |
| 1993 | Work continues on the Colorado Beef Cattle Production Model (CBCPM), a comprehensive, herd-wide, life cycle simulation program. In the last year we tested the interface between SPUR/CBCPM and FLIPSIM (an economic analysis model), removed a number of bugs, added additional output sections, and made a number of trial runs. We developed an long list of changes/enhancements that need to be made. We have made an extensive comparison of the energetics of CBCPM to NRC estimates. CBCPM is at this time rather optimistic in terms of animal performance. We have developed fairly sophisticated lag equations to simulated the effect of calf demand early in lactation on lactation-long milk production. We are continuing studies on terminal sire systems (Wade Shafer), accuracy of breeding value estimation (including postprocessing of model output, Echo Rantanen), and across-breed EPDs (Mark Enns). A dissertation involving the modeling of the effects of milk production in range cattle (Tim Steffens) nears completion, and a thesis on the simulated effects of cow maturing rate and milk production under Argentine conditions (Claudio Fioretti) has been defended and awaits the final draft. We have just initiated a study on the economics of artificial insemination in collaboration with Larry Van Tassel (U. of Wyo.) and his graduate student Angie McConnell. I (RMB) am now a member of WRCC-92 (Beef Cattle Energetics) which I hope will come up with a more mechanistic approach to energetics. |
| 1994 | Work continues on the Colorado Beef Cattle Production Model (CBCPM), a comprehensive, herd-wide, life cycle simulation program. Three theses involving extensive use of the model were completed in 1994, and another is in its final stages. The SPUR/CBCPM model was used to simulate Argentine beef production. A number of model refinements were needed to accommodate tame pastures and nitrogen fixing legumes. Both SPUR and CBCPM performed remarkably well, adding to our confidence in these models. Simulated interactions of environmental effects were similar to those reported in the literature -- again increasing our confidence in the ability of our mechanistic model to correctly mimic real interactions. A prototype was developed to output interface with SAS that will allow us to postprocess simulation results. We simulated grazing behavior of cows of different genotypes. This work indicated advantages for cattle with intermediate levels of milk and pointed out potential weaknesses in the intake portion of CBCPM. We will report on simulated tests of across-breed EPDs. This study is the most ambitious use of CBCPM to date and is the first to take full advantage of the model's deterministic/stochastic properties. This study documents some potential pitfalls in using current across-breed EPD tables for comparing sires from different breeds. |
| 1995 | 1994-95 was a sabbatical year for R.M. Bourdon. Research effort that would normally have been applied to Project COL00607 was diverted to writing a textbook. Work on the Colorado Beef Cattle Production Model (CBCPM) was, therefore, limited. The one study completed in 1995 involved simulation of performance of biologically diverse pure breeds of cattle, estimation of genetic parameters within each breed, and prediction of breeding value and complementarity of crosses of the simulated breeds. Results indicated that differences in genetic parameters between breeds are explainable biologically, and often depend on level of performance. The study raises questions about the utility of currently used tables for comparing expected progeny differences across breeds. We are currently configuring CBCPM to examine the long-term economics of artificial insemination in commercial beef cattle. We are also involved in a National Cattlemen's Association initiative to create a beef cattle simulation model to be used as a decision aid by production specialists. The project, if funded, will involve researchers from several universities plus ARS personnel. R.M. Bourdon has been named team leader, and CBCPM is likely to play an important role in the project. |
| 1996 | Work with the Colorado Beef Cattle Production Model (CBCPM) in 1995 resulted in two important new concepts in animal breeding. The first concept is that of physiological breeding value, a value describing an individual's breeding potential that is environment and population independent. The second concept is that of sire selection by simulation, a new technology for multiple-trait selection involving bio-economic simulation. Both concepts are important for integrating the fields of genetic prediction and production systems. Work is underway to combine the best beef cattle production models under the auspices of the Production Efficiency Task Force (PETF), a subcommitee of NCBA. CBCPM provides the framework for such a supermodel. Scientists of the U.S. Meat Animal Research Center and CSU are currently combining CBCPM with newer growth models, and developing user-friendly front end software. CBCPM was altered to allow for genetic trend in sires. The new version of the model was used in a joint research project with researchers at the University of Wyoming to test the economic benefit of artificial insemination (AI) in commercial beef herds. Preliminary results suggest that AI is not a profitable alternative. Analyses are nto complete, however. |
| 1997 | Problem: Beef cattle producers make production decisions based on subjective, often naive information. They need a system that will enable decision making based on objective information. Project description: This project involves development and application of a firm-level bioeconomic computer simulation model of beef cattle production. Accomplishments: Accomplishments in 1997 involved communication of ideas rather than concrete model results. "Shortcomings of Current Genetic Evaluation Systems" will be published in the Journal of Animal Science in 1998. This 55-page essay identifies problems with current statistical approaches to genetic prediction and multiple-trait selection, then proposes mechanistic solutions - i.e., solutions involving bioeconomic computer simulation of beef cattle production. It is the most in-depth articulation of the need for bio-economic simulation in animal breeding to date. Impact: It is too early to asess the impact of this work. It will depend upon whether decision support systems using computer simulation are developed and used on a large scale. That, in turn, depends on financial support. |
| 1998 | Problem. Beef cattle producers make production decisions based on subjective, often naive information. They need a system that will enable decision making based on objective information. Project Description. This project involves development and application of a firm-level bioeconomic computer simulation model of beef cattle production. Accomplishments. In 1998, plans were developed to validate the DECI model, a version of the Colorado Beef Cattle Production Model (CBCPM), at the San Juan Basin Research Center in Hesperus, CO. Beginning in May, 1999, the breeding program at the Hesperus station will include matings that will help relate published sire EPDs to model inputs. Work has begun on the redesign of DECI using principles of object-orientation so that the model will be easily understandable and modifiable in the future. CBCPM is currently being used to model the biological and economic effects of using sexed semen in commercial herds. Principles of multi-trait selection using simulation models were articulated at the 6th World Congress on Genetics Applied to Livestock Production in Australia, in two presentations in Canada, and in a paper in the Journal of Animal Science. Impact. It is too early to assess the impact of ongoing work with DECI and CBCPM. The talks and paper are generating interest. A core of investigators have organized themselves loosely to coordinate and pursue funding for DECI related work. |
| 1999 | Problem - Beef cattle producers make production decisions based on subjective, often naive information. They need a system that will enable decision making based on objective information. Project Description - This project involves development and application of a firm-level bioeconomic computer simulation model of beef cattle production. Accomplishments - In 1999, approximately 100 multibreed females at the San Juan Basin Research Center in Hesperus, CO were bred to eight biologically diverse, Red Angus and Limousin sires. Data on the production environment and the performance of offspring from these matings will be used to validate the DECI model, a version of the Colorado Beef Cattle Production Model (CBCPM), and relate published sire EPDs to model inputs. An initial redesign of DECI using principles of object-orientation has been completed. Once implemented, the design will make the model more understandable and modifiable in the future. Work continues using CBCPM to model the biological and economic effects of using sexed semen in commercial herds. |
| 2000 | Beef cattle producers make production decision based on subjective, often naive information. They need a system that will enable decision making based on objective information. This project involves development and application of a firm-level bioeconomic computer simulation model of beef cattle production. In 1998 plans were developed to validate components of the DECI model, a version of the Colorado Beef Cattle Production Model, CBCPM using resources at the San Juan Basin Research Center in Hesperus, CO. Beginning in May 1999 and continuing into the 2000 breeding season the breeding program at Hesperus included matings that will help relate published EPDs to model inputs. Additional work in 2000 included beginning the redevelopment of the reproduction portion of the CBCPM and foundation work to address design issues in an object oriented next generation of CBCPM. |
| 2001 | Development of a management systems approach to livestock production is an imperative as agricultural managers balance issues of profitability, sustainability, and environmental compatibility. This project is designed to assist development of management information and tools that can be utilized by agricultural and resource managers. The three primary efforts of the past year have been to 1) develop a series of case studies based on an in-depth analysis of three cow-calf ranches in the western plains and intermountain west of the United States. The production and geographic resources were evaluated, management practices were documented, and financial and biological performance indicators were determined. Based on this data, three extensive case studies were developed for use in undergraduate, graduate, and adult education programs. 2) An evaluation of cow-calf management practices was conducted in cooperation with USDA-APHIS:VS by comparing the NAHMS data with that collected from cow-calf producers in association with the National Market Cow and Bull Beef Audit and the National Fed Beef Audit. The results of these data provide educators, extension specialists, agency personnel, and agricultural industry participants significant information as to the gaps in actual industry management practices and the recommendations of Beef Quality Assurance Program initiatives and other GMPs as described by industry leaders. 3) A rancher's guide to the Clean Water Act and Endangered Species Act is in the final stages of preparation. As environmental regulations become more prevalent, livestock producers find themselves in a position of having to defend, evaluate, and modify traditional production practices. This collaborative work (Animal Sciences and Range Ecosystem Science) is based on a comprehensive literature review, the use of a university ranch as a case study, and the development of a model that helps ranchers evaluate their risk in terms of being subject to regulatory action. |
| 2002 | Development of a management systems approach to livestock production is critical as agricultural managers balance issues of profitability, sustainability, and environmental compatibility and the interactions of components of these issues. This project is designed to assist development of management information and tools that can be utilized by agricultural and resource managers. The primary efforts of the past year have been to: 1. Develop a computer simulation model that allows beef producers to make marketing decisions based on the expected progeny differences of sires for time to finish traits (i.e. time reach a target carcass weight, yield grade, or quality grade); 2. Complete the report examining the issues related to the intergenerational transfers of family farms; and 3. Publication of a rancher's guide to the Clean Water and Endangered Species Acts. The last effort was a collaborative work (Animal Sciences and Range Ecosystem Science) based on the use of a university ranch as a case study and the development of a model designed to help ranchers evaluate their risk in terms of being subject to regulatory action. |
| 2003 | The approach of traditional livestock research is to formulate a hypothesis that focuses on a single question and subsequently designs a study to answer that question. Traditional research may pose questions such as what is the effect of a particular implant on growth rate, what is the selection progress in calving ease given we select on birth weight, or what influence does a particular diet have on conception rate? Because of resource constraints little effort has focused on the effects of these management or genetic changes on the whole beef production system both in performance and economic terms. Yet, through the integration of four research/teaching facilities, we have implemented a beef production system that includes a seedstock supplier, a multiplier, a commercial herd, and a feedlot. Germplasm in the form of semen and live animals have been moved down the system just as they would in the U.S. beef industry from seedstock to multiplier to commercial producer to feedlot. We have adopted a standardized performance recording system and are developing methods for tracking economic performance of each facility and on the system as a whole. This production system will allow us to evaluate the effects of individual research projects and management changes on the entire production system and is, we believe, a first for a university beef research program. In addition, a simulation model was developed that examines the economic impact of artificial insemination versus natural service when genetic differences exist between potential sires available for both of those mating methods. The model accounting for marketing at different stages of production such as at weaning, and at slaughter on both a live and grid system was parameterized with data from the Red Angus Association of America, one of the clients of the CSU Center for Genetic Evaluation of Livestock. |
| 2004 | A prototype web-based decision support system has been developed to quantify the productive and economic implications of using various sires within the context of a cow-calf system. (The web address is ert.agsci.colostate.edu). The background to the system is recognition that producers can readily identify the economically relevant traits (ERTs) that impact their production system but real-life selection decisions involve choosing among candidates that are favorable with respect to some attributes but typically have below average merit for at least one ERT trait. Determining the overall net merit of each individual with varying genetic merit across the portfolio of economically relevant traits is problematic. Clear evidence for the difficulty in valuing concurrent genetic change for all the traits influencing system performance is the lack of published information quoting the annual value of genetic change to the cow-calf component of the beef industry. Although it may be relatively straightforward to quantify the change in value of a calf as a result of selection, the impact of such change on cow-calf system profitability requires knowledge of changes in herd age structure, time preference and nutritional requirements of the breeding cows and their replacements. The decision support system is linked to a database of bull EPDs. The user can enter information relating to the whole herd performance of their current production system and then use simple database filters to select individual sires that might appeal to them. The downstream implications of using each of those sires, within the context of the users own production system, can then be quantified. In a maternal context it is assumed that the daughters of the bull in question are retained as replacements and flow through the various age groups of the foundation herd. The herd size can be rescaled to ensure that the annual feed consumed by the improved herd is identical to the annual requirements of the unimproved herd. Thus the animal numbers are scaled appropriately to account for the fact that most productive changes alter the nutritional requirements of the herd. The value of any change in income must also account for the change in scale in order to predict the whole system influence. The genetic evaluation of cattle in the US is likely to move to an across-breed system over the next few years. The resultant EPDs will therefore be comparable on a single base, facilitating the comparison of animals of different breeds or breed crosses. The performance of crossbred animals will be influenced by heterosis or hybrid vigor for all the ERTs. Subsequent versions of this decision support system will take advantage of across-breed EPDs and knowledge of heterosis while maintaining the same functionality, look and feel. |
| 2005 | A prototype decision support system (DSS) accessible via the web (ert.agsci.colostate.edu) has been significantly enhanced. The system quantifies the productive and economic implications of using various sires within the context of a cow-calf system. It has been modified for routine use by seedstock producers and commercial ranchers. Sire information from the Brangus, Limousin, Red Angus, Salers, Simmental, Shorthorn and South Devon breed associations have been used to populate the database. Although producers can readily identify the economically relevant traits (ERTs) that impact their production systems, real-life selection decisions involve choosing among candidates that may be above-average for some attributes and below-average for others. Superiority or inferiority of a particular trait in this context is measured by expected progeny differences (EPDs). Such EPDs cannot be observed and are predicted from statistical analysis of pedigree and performance records. The resulting EPDs vary in their accuracy, reflecting the level of confidence that these values will not change when further information is collected. A method to account for possible change in EPDs has been developed using Monte-Carlo simulation procedures. The results will be used within the web system to quantify risk by generating the distribution of relative profit of alternative bulls. These distributions can be used to quantify the probability that one sire will be more profitable than another, and to report the associated increase (or decrease) in profitability. This allows users to discriminate, using their own attitude to risk, between sires that have identical EPDs but different levels of confidence associated with the EPDs. A further model to predict post-weaning (ie feedlot) performance from relevant EPDs in terms of time to finish, feed to finish and value at finish has been designed, and will in future be incorporated as a web-based tool along with the existing cow-calf production model. |
| 2006 | The database query and data entry components of the decision support system (DSS) accessible via the web (ert.agsci.colostate.edu) have been significantly enhanced. The system quantifies the productive and economic implications of using various sires within the context of a cow-calf system. It is available for routine use by seedstock producers and commercial ranchers. Sire information from the Brangus, Limousin, Red Angus, Salers, Simmental, Shorthorn and South Devon breed associations have been used to populate the database. Although producers can readily identify the economically relevant traits (ERTs) that impact their production systems, real-life selection decisions involve choosing among candidates that may be above-average for some attributes and below-average for others. Superiority or inferiority of a particular trait in this context is measured by expected progeny differences (EPDs). Such EPDs cannot be observed and are predicted from statistical analysis of pedigree and performance records. The system uses these predictions to quantify likely phenotypic performance for a suite of economically relevant traits. These enable the likely income and expenditure to be determined and compared according to alternative choice of sire. A further model to predict post-weaning (ie feedlot) performance from relevant EPDs in terms of time to finish, feed to finish and value at finish has been designed, and is in prototype stage. It will in future be incorporated as a web-based tool along with the existing cow-calf production model. |
| Impact | |
| 1999 | The Hesperus breeding project is a long-term study, and it is too early to assess its impact. A group of investigators doing DECI related work is now organized and pursuing coordinating committee status with CSREES. |
| 2000 | It is too early to assess the impact of ongoing work with DECI and CBCPM. A group of researchers from several universities have developed a proposal for a regional coordinating committee focused on model development. |
| 2001 | Livestock producers serve a vital role in the delivery of high quality proteins to consumers in the United States and abroad. Furthermore, they have a critical role in the management of resources that promotes both profitability and the long-term viability of those resources. This project has utilized resources to evaluate production practices, to develop meaningful comparisons, and to build useful case studies that allow producers to make better decisions in the light of increasing societal and governmental scrutiny. |
| 2002 | Once validated, the simulation model will be released to breed associations and producers via the web allowing them to make marketing decisions and potentially increase profitability through value-based marketing of finished animals as opposed to marketing on an average, live basis. With the increase in value-based marketing programs in the beef industry, a tool such as this is a critical component of the management systems approach. The report on the intergenerational transfer of family farms will allow families to plan for, rather than react to, issues involved in those transfers of farms and ranches. Finally the last project provides producers with a tool to aid decision-making under a system with increasing societal scrutiny and governmental regulation. |
| 2003 | The mating simulation model will allow producers to evaluate the economic impact of implementing synchronization and artificial insemination programs, given their individual marketing plans. While parameterized with Red Angus data, the simulation can be applied to any breed or composite. The integrated production system will allow evaluation of new animal identification systems that with the discovery of BSE will likely be developed and implemented in the industry as a means of animal traceback. Additionally we expect the results of this program to provide producers with decision tools that will improve their profitability. |
| 2004 | The national cow-calf herd includes over 30 million breeding cows. An improvement in productivity equivalent to 1 lb weaning wt per cow is worth at least twenty million dollars per year in perpetuity. Selection over recent decades has considerably changed the nature of the national beef herd, but the value of such change in terms of genetic improvement is unclear. Some of the trait changes have been favorable while others have been unfavorable. For example, while weaning weight has increased (a favorable change), there has also been change in mature cow size (unfavorably increasing nutritional requirements) decline in reproductive performance and reduction in longevity. Decision support tools such as that being prototyped in this project, offer the evaluation of concurrent changes in the context of whole system productivity and profitability. The potential impact of such a tool if adequately funded and communicated is therefore enormous. To date, the prototype tool has been demonstrated to all the major US beef breed associations and to many individual breeders and groups of breeders. In conjunction with the development of multi-breed evaluations, such a decision support system may become recognized as one of the major milestones in livestock improvement, along with performance recording, progeny testing, genetic evaluation and artificial insemination. |
| 2005 | Improved productivity by selection, equivalent to a 1 lb increase in weaning wt per breeding cow is worth at least $20 million per year in perpetuity, given the national cow-herd comprising some 30 million cows. Such improvement does not necessarily imply an increase in industry output, as the progress may allow rangeland resources to be redirected to other uses, such as enhancing wildlife values or conserving riparian zones. The DSS will allow the value of annual genetic changes to be reliably quantified, providing decision makers with the tool to ensure that valuable selection opportunities are directed at improvement rather than simply change. The subtle distinction between improvement and change is important because selection for favorable attributes such as growth rate are associated with erosion of performance for other characteristics such as feed requirements or reproductive performance unless predicted performance in all the economically relevant attributes are simultaneously taken into account. Tools that can increase profitability in the cow-calf sector will produce downstream effects in feedlots, meat packing plants and ultimately at the consumer level. However, the nature and scope of such downstream changes are difficult to predict as these are influenced by the collective behavior of all sectors of the supply chain. The impact of decision support developments also opens up opportunities for the delivery of multi-breed genetic evaluations, which would provide for across-breed comparison of sires, accounting for the effects of breed differences and heterosis. |
| 2006 | Improved productivity by selection, such as a 1 lb increase in weaning wt per breeding cow is worth at least $20 million per year in perpetuity, given the national cow-herd of some 30 million cows. Such improvement does not imply an increase in industry output, as cow numbers may be reduced to allow rangeland resources to be redirected to other uses, such as enhancing wildlife value. The DSS will allow the value of annual genetic changes to be reliably quantified, to ensure that valuable selection opportunities are directed at improvement rather than simply change. The subtle distinction between improvement and change is important because selection for favorable attributes such as growth rate are associated with erosion of performance for other characteristics such as feed requirements or reproductive performance unless predicted performance in all the economically relevant attributes are simultaneously taken into account. Tools that can increase profitability in the cow-calf sector will produce downstream effects in feedlots, meat packing plants and ultimately at the consumer level. However, the nature and scope of such downstream changes are difficult to predict as these are influenced by the collective behavior of all the sectors of the supply chain. This decision support system opens up opportunities for the delivery of multi-breed genetic evaluations, allowing across-breed comparison of sires, accounting for the effects of breed differences and heterosis. Multi-breed evaluation is a major undertaking being developed in the context of a companion project. |
| Publications | |
| 1993 |
BOURDON, R.M. 1993. Evaluating production alternatives with computer simulation. Proc. Matching Beef Cattle to Western Environments Sympoisum. Phoenix, AZ and Calgary, AB. BOURDON, R.M. AND R.E. TAYLOR. 1993. Breeds and biological types -- what is the differnce. BEEF. February. BRINKS, J.S. AND R.M. BOURDON. 1993. Workshop: Matching cattle to resources and fine-tuning the breeding program. Proc. Matching Beef Cattle to Western Environments Symposium, Phoenix, AZ and Calgary, AB. |
| 1994 |
BOURDON, R.M. 1994. Breed roles in hitting a new target. Proc. BIF 26th Research Symposium and Annual Mtg. p. 115. BOURDON, R.M. 1994. Nuevos enfoques en seleccion. Chacra Magazine. Buenos Aires, Argentina. February FIORETTI, C.C. 1994. Simulated rates of maturity and milk production effects on biological efficiency of beef production in Argentina. Ph.D. Dissertation. Kansas State University. RANTANEN, E. 1994. Biological simulation: Environmental effects on weaning weight and prototype interface. M.S. Thesis. Colorado State University. STEFFENS, T. 1994. Grazing behavior and intake as affected by cattle biological type on mixed grass prairie. Ph.D. Dissertation. Colorado State University. |
| 1995 |
ENNS, R.M. 1995. Simulation of across-breed comparisons for direct and maternal weaning weight in beef cattle. Ph.D. Dissertation. Colorado State University, Fort Collins MALLINCKRODT, C.K., GOLDEN B.L. and BOURDON, R.M. 1995. The effect of selective reporting on estimates of weaning weight parameters in beef cattle. J. Anim. Sci. 73:1264 SNELLING, W.M., GOLDEN, B.L. and BOURDON, R.M. 1995. Within-herd genetic analysis of stayability of beef females. J. Anim. Sci. 73:993 |
| 1996 |
Al-HUR, FAHAD S. 1996. Factors affecting immunoglobulin G concentration and total solids percentage in ewe colostrum. M.S. Thesis. Colo. State Univ., Fort Collins BERTRAND, K., R. BOURDON, L. CUNDIFF, B. CUNNINGHAM, B. GOLDEN, J. POLLAK, R. QUAAS, R. SCHALLES, D. VAN VLECK, R. WILLHAM, and D. WILSON. 1996. National Cattle Evaluation. Guidelines for Uniform Beef Improvement Programs. 7th Ed. Beef Improvement Federation BOURDON, R.M. 1996. Physiological breedng values: An alternative way of presenting national cattle evaluation data. Proceedings: BIF Systems Workshop II: Multiple-Trait Selection Tech. for North American Beef Production, Estes Park, CO BOURDON, R.M. 1996. Sire Selection by Simulation. Proceedings: BIF Systems Workshop II: Multiple-Trait Selection Technology for North American Beef Production, Estes Park, CO BOURDON, R.M. 1996. Understanding Animal Breeding. Prentice Hall, Upper Saddle River, NJ BOURDON, R.M., D.A. DALEY, and J.W. OLTJEN. 1996. Compositive cattle for commercial cow-calf producers. Cow-Calf Handbook. California Cooperative Extension Service CHOY, Y.H., J.S. BRINKS, and R.M. BOURDON. 1996. Genetic evaluation of mature weight, hip height, and body conditon score in an Angus herd. J. Anim. Sci. 74(Suppl. 1):107. (Abstr.) ENNS, R.M., et al. 1996a. Simulation of diverse biological types I: genetic parameters and relationshps between EPF and physiological breeding values. J. Anim. Sci. 74(Suppl. 1):113. (Abstr. ENNS, R.M., R.M. BOURDON, J.S. BRINKS, B.L. GOLDEN, J.D. HANSON, and B.B. BAKER. 1996b. Simulation of diverse biological types II: breed complementaritiy. J. Anim. Sci. 74(Suppl.) 1):114. (Abstr.). --- EVANS, J.L., B.L. GOLDEN, C.R. COMSTOCK, K.L.LONG, R.M. BOURDON, C.H. MALLNCKRODT, and R.D. GREEN. 1996. Genetic parameter estimates for heifer pregnancy rate in Hereford cattle. J. Anim. Sci. (Suppl. 1):116. (Abstr.) GOLDEN, B.L. and R.M. BOURDON. 1996. Across breed EPDs for Red Angus using additive genetic groups. Proceedings: BIF 28th Research Symposium and Annual Meeting, Birmingham, AL, p. 106 GOLDEN, B.L., R.M. BOURDON, and C.R. COMSTOCK. 1996. A method for across breed comparison of expected progeny differences using additive genetic groups. J. Anim. Sci. (74 (Suppl. 1):114. (Abstract) |
| 1998 |
Bourdon, R.M. 1998. Determining selection objectives using the DECI model: a progress report. Proc. 30th Annual Mtg. Beef Improvement Federation, July 1-2, Calgary, AB. Bourdon, R.M. 1998. Shortcomings of current genetic evaluation systems. J. Anim. Sci. 76:2308 Bourdon, R.M. and Enns, R.M. 1998. Physiological breeding values: rethinking the way we express genetic values for improving production systems. Proc. 6th World Congress on Genetics Applied to Livestock Production, Jan. 11-16, Univ. of New England, Armidale, NSW, Australia. Vol. 27, p. 227 Choy, Y.H., Brinks, J.S., and Bourdon, R.M. 1998. Effect of age on the genetic relationships between size and condition score in Angus cows. Colorado State Univ. Beef Program Rep. p. 67 Choy, Y.H., Brinks, J.S., and Bourdon, R.M. 1998. Genetic evaluation of mature weight, hip height and body condition score in an Angus herd. Proc. Western Section, Am. Soc. Anim. Sci. 49:61 Choy, Y.H., Brinks, J.S., and Bourdon, R.M. 1998. Genetic evaluation of mature weight, hip height and body condition score in an Angus herd. J. Bourdon, R.M. 1998. Maintaining market share: a sensible priority? Cattle Guard. September issue Comstock, C.R. and Bourdon, R.M. 1998. Exploring the RAAA's pedigree. American Red Angus. February issue Comstock, C.R. and Bourdon, R.M. 1998. Further exploration of the RAA pedigree. American Red Angus. April issue |
| 1999 |
Bourdon R. M. 1999. Composites 101. Rev. Bras. Reprod. Anim,. vol. 23, no. 2, p. 122 Bourdon, R. M. 1999. Biotechnology and composite cattle breeding. Rev. Bras. Reprod. Anim,. vol. 23, no. 2, p. 118 Bourdon, R. M. 1999. Cattle breeding technologies in perspective. BEEF. vol. 35, no. 8A, p. 42 Bourdon, R. M. and Golden. B.L. 1999. Beef cattle breeding in the new millenium. American Red Angus, vol. XXXV no. 2, p. 30 Evans, J. L., Golden, B.L., Bourdon, R.M., and Long, K.L. 1999. Additive genetic relationships between heifer pregnancy and scrotal circumference in Hereford cattle. J. Anim. Sci. 77:2621 Golden, B. L. and Bourdon, R.M. 1999. New EPDs: a rational vision for the future. Proc. 31st Annual Res. Symposium and Annual Mtg., June 6-8, Roanoke, VA, p. Golden, B. L. and Bourdon, R.M. 1999. The sire summary of the future. Rev. Bras. Reprod. Anim, . vol. 23, no. 2, p. 78 R. D. Green, Niswender, G.D., Field, T.G., Whittier, J.C., Roath, L.R., Garry, F.L., Dalsted, N.L., and Hoag, D.L. 1999. The Western Center for Integrated Resource Management. Proc. WSASAS , vol. 50 R. L. Doherty, Field, T.G., Tatum, J.D., Belk, K.E., Scanga, J.A., and Smith, G.C. 1999. Developing benchmarks to familiarize cattle producers with the benefits and risks associated with grid pricing. Prof. Anim. Sci. 15:2 |
| 2001 |
Behrends, L. 2001. An analysis of U.S. cow-calf management practices, M.Ag. Thesis, Fall, Colorado State University. Behrends, L., Field, T.G., and Conway, K. 2001. The value of information as perceived by feedlot managers. Animal Sciences Research Report. Colorado State University, Ft. Collins, CO. Berger, A. 2001. An evaluation of three ranches to create teaching case studies, M.S. Thesis, Spring, Colorado State University. Foster, Holly. 2001. Evaluation of two modifications to estrous synchronization protocols using GnRH and PGF, M.S. Thesis, Spring, Colorado State University. |
| 2002 |
Cleveland, M 2002. Sire Selection for optimum finish endpoints, M.S. thesis, Colorado State University, Fall 2002, 160 pages. Grether, N. 2002. A Ranchers' Guide to the Clean Water and Endangered Species Acts. M.S. Thesis, Colorado State University, Summer 2002, 53 pages. Grether, N. and Summer, M.A. 2002. Farm Futures: A report presenting issues relating to the intergenerational transfers of family farms. USDA:NCRS, 52 pages. |
| 2003 |
Cleveland, M.A., Enns, R.M., Umberger, W.J., and Golden, B.L. 2003. Simulation of net return using days to finish estimated breeding values in beef production. J. Anim. Sci. 81:89. Supplement 1. Comstock, S. 2003. Heifer pregnancy genetic prediction and simulation modeling techniques. Ph .D. Dissertation. Colorado State University. Fort Collins. Enns, R.M, and Garrick, D.J. 2003. The economic benefits and potential when using current and future EPD Economically Relevant Traits. Proceedings, The Range Beef Cow Symposium XVIII. Scottsbluff. Pp. 46-53. Field, T. 2003. Tools for Making Genetic Change. Proceedings of the 35th Annual Research Symposium and Annual Meeting. Beef Improvement Federation. pp 42-47. Garrick, D.J. 2003. Cross-breeding and composite breed formation. In: The Role of Composites in Livestock Production, Proceedings of the 2003 Animal Industries Workshop. ISBN 0-86476-155 pages 21-29. Garrick, D.J. and R.M. Enns, R.M. 2003. How best to achieve genetic change? Proceedings of the Beef Improvement Federation 35th Annual Research Symposium and Annual Meeting. Pp 48-50. Jubileu, J. 2003. The use of random regression models to predict days to finish in beef cattle . M.S. Thesis. Colorado State University. Fort Collins. Jubileu, J.S., Maiwashe, N., Cleveland, M., Tsevenjaav, B., Enns R.M., and Garrick, D.J. 2003. Estimates of genetic parameters of carcass traits in Limousin cattle. Abstract only, W96. Journal of Animal Science, 81:318, Suppl. 1. Lopez-Villalobos, N. and Garrick, D.J. 2003. Accounting for feed intake in dairy cattle evaluation. Proceedings of the Association for the Advancement of Animal Breeding & Genetics 15th Conference, 15:318-321. Shafer, W. 2003. The Colorado Beef Cattle Production Model: effects of simulation with realistic levels of variability and extreme within-herd diversity. Ph.D. Dissertation. Colorado State University. Fort Collins. Speidel, S.E., Enns, R.M., Garrick, D.J., Welsh, C.S., and Golden, B.L. 2003. Current approaches to performing large scale beef cattle genetic evaluations, Proc. West Sect. Am. Soc . An. Sci. Vol. 54. 7 pages. Welsh, C.S., Golden, B.L., Enns, R.M., Garrick, D.J., and G.B. Nicoll, G.B. 2003. Influence of birth weight and birth rank on lamb survivability. J. Anim. Sci. 81:68. Supplement 1. |
| 2004 |
Ahola, J.K., Baker, D.S., Burns, P.D., Mortimer, R.G., Enns, R.M., Whittier, J.C.,. Geary, T.W ., and Engle, T.E. 2004. Effect of copper, zinc, and manganese supplementation and source on reproduction, mineral status, and performance in grazing beef cattle over a two-year period. J . Anim Sci. 82: 2375-2383 Brigham, B.W., Garrick, D.J., and Enns, R.M. 2004. Development of web-based cow-calf decision support software. Abstract. Journal of Animal Science 82:Suppl.1 pp 391. Burns, E.M., Enns, R.M., and Garrick, D.J. 2004. The status of equine genetic evaluation. Proceedings of the Western Section of Animal Science 55:82-86. Cleveland, M.A. Enns, R.M., Garrick, D.J., and Blackburn, H.D. 2004. Examining the genetic diversity of Hereford cattle. Abstract. Journal of Animal Science 82:Suppl.1 pp 451. Evans, R.D. Dillon, P., Shalloo, L., Wallace, M., and Garrick, D.J. 2004. An economic comparison of dual-purpose and Holstein-Friesian cow breeds in a seasonal grass-based system under different milk production scenarios. Irish Journal of Agriocultural and Food Production Research 43:1-16. Garrick, D.J. 2004. Developing a Breeding Program. Proceedings of the Fiber to fashion: fashioning our alpacas future Conference held at Reno Nevada. 4-8 February 2004, pp 36-41. Garrick, D.J. 2004. High-altitude disease - an example of genetic variation for adaptability. Proceedings of the NBCEC Adaptability Symposium held in Kansas City 29-30 October 2004. Garrick, D.J. 2004. Linebreeding & Crossbreeding. Proceedings of the Fiber to fashion: fashioning our alpacas future Conference held at Reno Nevada. 4-8 February 2004, pp 42-47. Garrick, D.J. and Enns, R.M. 2004. Selecting for economically relevant traits. Proceedings of the Beef Seedstock Conference on Genetic Innovations for Breeding Programs held by the Iowa Beef Center in Ames Iowa, 2 December 2004. Maiwashe, A. Garrick, D.J., and Enns, R.M. 2004. Weighting of information when predicting breeding values using the standard or marker-based inverse of the numerator relationship matrix. Abstract. Journal of Animal Science 82:Suppl.1 pp 243. Miller, K.E., Whittier, J.C., Peel, R.K., Enns, R.M., Bruemmer, J.E., and Umberger, W.J. 2004. Case Study: Comparison of breeding and marketing systems for Red Angus cattle using an integrated computer-based spreadsheet. The Professional Animal Scientist 20: 429-436. Olson, K.M., Garrick, D.J., and Enns, R.M. 2004. Predicting breeding values for feed intake from individual or pen-fed data. Abstract. Journal of Animal Science 82:Suppl.1 pp 452. Speidel, S.E., Garrick, D.J., and Enns, R.M. 2004. Genetic prediction for estimating mature cow maintenance energy requirements. Abstract. Journal of Animal Science 82:Suppl.1 pp 450. Sprinkle, J.E., Cuneo, S.P., Frederick, H.M., Enns, R.M., Schafer, D,W, Carstens,G.E., Slay, L .J., Daugherty, S.B., Noon, T.H., Rickert, B.M., and Reggiardo, C. 2004. Effects of a long acting trace mineral rumen bolus upon range cow productivity. WSASAS. Vol 55. Pp 362-366. Sprinkle, J.E., Cuneo, S.P., Frederick, H.M., Enns, R.M., Schafer, D.W., Carstens, G.E., Slay, L.J., Daugherty, S.B., Noon, T.H., Rickert, B.M., and Reggiardo, C. 2004. Effects of a long acting trace mineral rumen bolus upon range cow and calf trace mineral profiles. WSASAS. Vol 55. Pp 357-361. Tseveenjav, B., Garrick, D.J., Levalley, S., Kimberling, C., and Zagsduren, Y. 2004. Economic selection indexes to improve fiber production for cashmere goats in Mongolia. Abstract from Western Section of Animal Science. Journal of Animal Science 82:Suppl.2 pp 110. Walker, R.S., Downing, E.R., Enns, R.M., and Zalesky, D.D. 2004. Improving fertility in beef heifers with GnRH at timed AI using a modified Co-Synch plus CIDR protocol. Departmental Research Report. Department of Animal Sciences, Colorado State University. (http://www.ansci .colostate.edu/documents/04ResearchReports/Fertilityinbeefheifers.pdf) 4 pp. Walker, R.S., Enns, R.M., Geary, T.W., Wamsley, N.W., Downing, E.R., Mortimer, R.G., LaShell, B.A., and Zalesky, D.C. 2004. Fertility in beef heifers synchronized using a modified CO-Synch plus CIDR protocol with or without GnRH at time AI. Proceedings of the 2004 WSASAS. Vol 55. Pp 3-6. Wamsley, N.E., Burns, P.D., Engle, T.E., and Enns, R.M. 2004. Fish Meal Supplementation alters Uterine Prostaglandin F2x Synthesis in Beef Heifers Having Low Luteal Phase Progesterone. 2004 Departmental Research Report. Department of Animal Sciences, Colorado State University. (http://www.ansci.colostate.edu/documents/04ResearchReports/Fishmealsupplementation.pdf) 6 pp. |
| 2005 |
Ahola, J.K., Baker, D.S., Burns, P.D., Whittier, J.C., and Engle, T.E. 2005. Effect of Copper, Zinc and Manganese Source on Mineral Status, Reproduction, and Calf Performance in Young Beef Females over a Two Year Period. The Professional Animal Scientist 21:297-304. Brigham, B.W., Enns, R.M., and Garrick, D.J. 2005. Using additional phenotypic information in data poor analyses. Proc. West. Sect. Am. Soc. An. Sci. 56: 105-108. Enns, R.M., Garrick, D.J., and Brigham, B.W. 2005. Variability in economic value is dependent upon herd average stayability. Proceedings of the Western Section of the American Society of Animal Science, 56:112-115. Enns, R.M., Garrick, D.J., and Brigham, B.W. 2005. Variability in economic value is dependent upon herd average stayability. Proc. West. Sect. Am. Soc. An. Sci. 56: 112-115. Garrick, D.J. 2005. High Altitude disease, an example of genetic variation for adaptability. Proceedings of the Beef Improvement Federations 37th Annual Research Symposium and Annual Meeting held 6-9 July 2005 in Billings, Montana. 37:122-123. Garrick, D.J. 2005. Making the web equal profit, surfing for genetics. Proceedings of the Beef Improvement Federations 37th Annual Research Symposium and Annual Meeting held 6-9 July 2005 in Billings, Montana. 37:105-111. Garrick, D.J. 2005. Some tools to support genetic improvement. Proceedings of the University of Missouri in-service training for livestock and dairy specialists. CD-ROM. Garrick, D.J. 2005. Trends and developments in genetic evaluation of beef cattle in the United States. Proceedings of the 9th World Angus Forum Technical Meeting, Angus in the Global Market , pp 24-31. Garrick, D.J. 2005. Using appropriate genetic evaluations to make better selection decisions. Abstract. Journal of Animal Science 83, Suppl. 1, 327. Killinger, K.M., Calkins, C.R., Umberger, W.J., Feuz, D.M., and Eskridge, K.M. 2004. A comparison of consumer sensory acceptance and value of domestic beef steaks and steaks from a branded, Argentine beef program. Journal of Animal Science. 82:3302-3307. Killinger, K.M., Calkins, C.R., Umberger, W.J., Feuz, D.M., and Eskridge, K.M. 2004. Consumer sensory acceptance and value for beef steaks of similar tenderness, but differing in marbling level. Journal of Animal Science. 82:3294-3301. Killinger, K.M., Calkins, C.R., Umberger, W.J., Feuz, D.M., and Eskridge, K.M. 2004. Consumer visual preference and value for beef steaks differing in marbling level and color. Journal of Animal Science. 82:3288-3293. Mackay, W.S., Whittier, J.C., Field, T.G., Umberger, W.J., Teichert, R.B., and Feuz, D.M. 2004 . Case Study: To Replace or Not to Replace: Determining Optimal Replacement Rates in Beef Cattle Operations. Professional Animal Scientist. 20(2004):87-93. Shafer, W.R., R.M. Enns, B.B. Baker, L.W. VanTassell, B.L. Golden, W.M. Snelling, C.H. Mallinckrodt, K.J. Anderson, C.R. Comstock, J.S. Brinks, D.E.Johnson, J.D. Hanson, and R.M. Bourdon. 2005. Bio-economic simulation of beef cattle production: The Colorado Beef Cattle Production Model. 101 pages. AES Technical Bulletin TB05-02. Colorado State University, Fort Collins. Walker, R. S., P. D. Burns, J. C. Whittier, G. E. Sides, and D. D. Zalesky. 2005. Evaluation of Gonadotropin-Releasing Hormone and Insemination Time Using the COSynch Protocol in Beef Cows. The Professional Animal Scientist 21:190-194. Whittier, J. C., G. P. Lardy, and C. R. Johnson. 2005. Symposium Paper: Pre-Calving Nutrition and Management Programs for Two Year Old Beef Cows. The Professional Animal Scientist 21 (2005):145-150. |
| 2006 |
Beckman D.W., S.E. Speidel, B.W. Brigham, D.J. Garrick, and R.M. Enns. 2006. Genetic parameters for stayability and body condition score in beef females. Proceedings Western Section, American Society of Animal Science, 57:93-95. Beckman, D.W., S.E. Speidel, B.W. Brigham, D.J. Garrick and R.M. Enns. 2006. Genetic parameters for stayability and body condition score in beef females. Abstract. Journal of Animal Science 84, Suppl.2, 144. Brigham B.W., S.E. Speidel, D.W. Beckman, D.J. Garrick, W. Vanderwert, S. Willmon, and R.M. Enns. 2006. Parameter estimates and breeding values for days to a constant fat endpoint. Proceedings Western Section, American Society of Animal Science, 57:79-81. Brigham, B.W., S.E. Speidel, D.W. Beckman, D.J. Garrick, S. Willmon, W. Vanderwert and R.M. Enns. 2006. Parameter estimates and breeding values for days to finish to a constant endpoint. Abstract. Journal of Animal Science 84, Suppl.2, 143. Bullock, K.D., D.R. Strohbehn, R.L. Weaber, E.J. Pollak, D.J. Garrick, J.K. Bertrand, D.W. Moser and J.M. Reecy. 2006. From research to application: a model for educating beef producers in animal breeding technologies. Proceedings of the Eighth World Congress on Genetics Applied to Livestock Production. 34_601-850 Enns, R.M. 2006. Selection Decisions: Tools for economic improvement beyond EPD. In: Beef Sire Selection Manual. National Beef Cattle Evaluation Consortium. Eds: K. D. Bullock, coordinator. pp. 55-62. Enns, R.M., D.J. Garrick and B.W. Brigham. 2006. Economic values of heifer pregnancy and stayability vary with average herd performance. Proceedings of the Eighth World Congress on Genetics Applied to Livestock Production. 31_927-2053. Evans, R.D., M. Wallace, L. Shalloo, D.J. Garrick and P. Dillon. 2006. Financial implications of recent declines in reproduction and survival of Holstein-Friesian cows in spring-calving Irish dairy herds. Agricultural Systems 89:165-183. Garrick, D.J. 2006. Development of genetic evaluations and decision support to improve feed efficiency. Proceedings of the Beef Improvement Federation's 38th Annual Research Symposium and Annual Meeting. 38:32-40. Garrick, D.J. 2006. Genetic improvement - assessing the ramifications of genetic change. Invited. Proceedings of the Eighth World Congress on Genetics Applied to Livestock Production. 3_466-1550. Garrick, D.J. 2006. The evaluation, interpretation and relevance of stayability in genetic improvement of beef cattle. Invited. Abstract. Journal of Animal Science 84, Suppl.2, 87. Lopez-Villalobos, N. and D.J. Garrick. 2006. Crossbreeding Systems for Dairy Production in New Zealand. Invited. Invited. Proceedings of the Eighth World Congress on Genetics Applied to Livestock Production. 32_1024-1774. Sherlock, R.G., P.R. Amer and D.J. Garrick. 2006. AnimalSim - simulating animal populations using quantitative and QTL information. Proceedings of the Eighth World Congress on Genetics Applied to Livestock Production. 27_957-1423. Speidel S.E., R.M. Enns, D.J. Garrick. 2006. Potential re-ranking of sires for weaning weight in above- and below-average environments. Proceedings Western Section, American Society of Animal Science, 57:82-85. Speidel, S.E., R.M. Enns and D.J. Garrick. 2006. Insignificant re-ranking of sires for weaning weight in above- and below-average environments. Abstract. Journal of Animal Science 84, Suppl .2, 143. Tseveenjav, B., D.J. Garrick and Y. Zagsduren. 2006. Simulation model for cashmere production system to improve fiber quality in Mongolia. Proceedings of the Eighth World Congress on Genetics Applied to Livestock Production. 5_162-361. |