Implementation of Genetic Selection for Grazing Distribution to Make Cattle Grazing in the Western US More Sustainable

Project Overview

Project Type: Research and Education
Funds awarded in 2015: $271,217.00
Projected End Date: 02/28/2019
Grant Recipient: New Mexico State University
Region: Western
State: New Mexico
Principal Investigator:
Dr. Derek Bailey
New Mexico State University

Annual Reports


  • Animals: bovine


  • Animal Production: free-range, grazing management, livestock breeding, preventive practices
  • Education and Training: extension, farmer to farmer, networking, on-farm/ranch research, participatory research
  • Natural Resources/Environment: habitat enhancement, riverbank protection
  • Sustainable Communities: new business opportunities

    Proposal abstract:

    Most environmental issues associated with cattle ranching in the West result from cattle congregating near water and in gentle terrain. Transferring grazing use from gentle terrain near water to moderately steep slopes and areas far from water would reduce degradation of riparian areas, prevent forage from becoming rank and unpalatable to big game, and minimize buildup of fine fuels. Previous Western SARE funded research (SW98-064 and SW09-054) demonstrated the potential to use genetic selection to manipulate grazing distribution. In SW98-064, we showed that some cattle are more willing to travel away from water and forage on steeper slopes (hill climbers), while others graze gentle terrain near water (bottom dwellers). Removal of bottom dwellers resulted in less grazing in riparian areas, more uniform distribution, and light and sustainable use of steep slopes. Earlier research (SW98-064) demonstrated that terrain use was not related to calf weaning weight or cow reproduction and disposition. Therefore, genetic selection for grazing distribution should not affect cattle performance but may allow for sustainable increases in stocking levels. The SW09-054 study showed that grazing distribution could be inherited and demonstrated the potential for practically applying selection to manipulate cattle grazing patterns. However, these results were based on 160 cows and additional research is needed before these exciting results can be used by ranchers. We propose to validate previously-identified genetic markers shown to be associated with cattle use of rugged terrain and areas far from water. We plan to verify and enhance prototype DNA test(s) that can be used to identify cows and bulls with superior and inferior grazing distribution genotypes. Potentially, these tests can be used to identify bulls that will sire daughters that use more rugged topography and travel farther water. These DNA tests could also be used to select (cull) cows with superior (inferior) genotypes. Such selections would not require expensive GPS tracking. Only a blood sample and DNA test would be needed, at a cost of potentially less than $30 per animal. Data from DNA tests are complex so we will develop molecular breeding values (MBV) for producers to use in their cattle breeding selection programs. The MBV will be similar to routinely calculated Expected Progeny Differences (EPDs) that ranchers regularly use to select bulls and replacement heifers. For this project to be successful and fully implemented, both ranchers and land managers must understand how genetic selection can improve “on-the-ground” grazing patterns. Educational programming will focus on showing ranchers how to submit DNA samples and then receive their cow's MBV for genetic selection of grazing distribution via workshops in New Mexico, Arizona, Colorado, and Nevada. Our team will develop factsheets, manuals, videos, and a website for MBVs so that ranchers can easily incorporate genetic selection for grazing distribution into their management programs. We will also hold professional conferences aimed at both ranchers and land managers to demonstrate how genetic selection for distribution can be combined with other practices to resolve livestock grazing issues.

    Project objectives from proposal:

    1. Validate previously identified genetic markers discovered from previous Western SARE funded research project (SW09-054) shown to be associated with cattle grazing distribution.

    A1. Track at least 200 cows with GPS collars for at least 2 months at 7 or more mountainous ranches in New Mexico, Arizona, Colorado, and Nevada.

    A2. Collect DNA samples from tracked cows.

    A3. Analyze DNA from tracked cows using High Density single nucleotide polymorphism (SNP) chip (BovineSNPHD; ~770,000 genotypes) and determine if previously identified genetic markers are similarly associated with grazing distribution traits as found in the previous Western SARE study SW09-054.

    B.  Verify and enhance prototype DNA test(s) for identifying superior and inferior genotypes for grazing distribution.

    B1. Analyze genetic markers used in a small prototype (180 SNP) panel with cows tracked in this project and compare associations to previously studied cattle herds.

    B2. Add or replace genetic markers in the prototype SNP panel so that the most predictive SNP are used in final DNA test.

    C.  Develop procedures and end user tools for estimating molecular breeding values (MBV) for grazing distribution.

    C1. Develop statistical procedures for estimating MBV for grazing distribution from cattle DNA samples.

    C2. Automate download of genotypes from DNA service providing company into CSU Center for Genetic Evaluation of Livestock (CGEL) software for estimating MBV.

    C3. Develop web-based software so producers can easily obtain the MBV for grazing distribution for each animal.

    D.  Provide training to ranchers and seedstock producers specifically designed to increase their knowledge and ability to utilize MBV to select cattle for improved grazing distribution.

    D1. Show ranchers how to collect DNA samples from cattle and how to submit the samples for analysis.

    D2. Teach ranchers how to obtain MBV from web-based systems for their cattle and utilize this information to select for improved grazing distribution.

    D3. Show how ranchers can incorporate grazing distribution goals and objectives into their ranch-specific breeding program.

    E. Estimate the potential for improvement of grazing distribution through MBV and genetic selection.

    E1. Estimate the potential for improvement in grazing distribution through genetic selection under varying scenarios.

    E2. Deliver this information to ranchers and land managers via multiple kinds of extension programs so they will know the potential for improving on-the-ground grazing use.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.