Genetic Influences on Cattle Grazing Distribution: Association of Genetic Markers with Terrain Use in Cattle

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Abstract

Eighty-seven cows were GPS (Global Positioning System) tracked for 1 to 3 months in mountainous and/or extensive pastures at five ranches located in New Mexico, Arizona, and Montana. The Illumina Bovine HD SNP array, which evaluates approximately 770,000 genetic markers (i.e., single nucleotide polymorphisms; SNPs) across the 30 bovine chromosomes, was used to genotype DNA from these cows and to examine genetic associations with grazing distribution. Terrain use indexes were calculated from tracking data based on normalized averages of slope use, elevation use, and distance travelled from water. Genetic analyses identified a chromosomal region, known as a quantitative trait locus (QTL), associated with these traits. One genetic marker on chromosome 29 identified a gene that has been reported to be involved in locomotion, motivation, and spatial memory. This locus accounted for 24% of the phenotypic variation in use of steep slopes and high elevations, while another QTL on chromosome 17 accounted for 23% of the phenotypic variation. Three other QTLs accounted for 10% to 20% of the variation in terrain use indexes. Using results from the initial high-density genetic marker analyses, a smaller 50-SNP panel was developed targeting previously identified QTL regions and was used to evaluate the 85 cows tracked previously with an additional 73 cows from four ranches. With the 50-SNP panel analyses, multiple genetic markers near or within the gene identified on chromosome 29 confirmed the association with indexes of terrain use. In addition, genetic markers on chromosomes 4, 8, 12, and 17 accounted for a significant portion of the phenotypic variation in terrain use indexes. The associations between terrain use indexes and genetic markers near candidate genes demonstrate that grazing distribution can be inherited and provide a new approach to associate genetic variation with cattle grazing behavior of range beef cattle.

Introduction

Most concerns associated with livestock grazing are the result of undesirable grazing distribution rather than stocking rate (Bailey, 2005). The western United States contains mountainous terrain and arid and semiarid climatic conditions. Cattle typically avoid steep slopes and congregate in gentle terrain (Mueggler, 1965). Many cattle do not travel far from water and usually graze within 2 km from water sources (Holechek, 1988, Valentine, 1947). Livestock are also attracted to areas with high forage quality (Bailey et al., 1996, Senft et al., 1987) and often spend a great deal of time in riparian areas (DelCurto et al., 2005, Roath and Krueger, 1982b). Concentrated grazing in preferred areas can lead to wildlife and fishery habitat degradation and impair streambank stability and riparian function (Kauffman and Krueger, 1984, Meehan and Platts, 1978), while slopes and areas far from water that receive little use provide opportunities for sustainably increasing stocking rates (Bailey, 2004). Fortunately, dietary and distribution preferences of livestock vary greatly among individual animals. Although most cattle graze gentle terrain near water (bottom dwellers), some cattle readily travel long distances from water and utilize steep and rugged terrain and could be considered hill climbers (Bailey et al., 2004, Bailey et al., 2006).

Transfer of grazing pressure from gentle terrain near water to rugged terrain and areas far from water can reduce degradation of riparian areas and improve habitat and water quality (Bailey, 2004, Launchbaugh and Howery, 2005). Several authors have suggested that selection of cattle that readily use rugged terrain and culling cows that prefer gentle terrain and areas near water would improve grazing distribution (Bailey, 2004, Howery et al., 1998, Roath and Krueger, 1982a). Bailey et al. (2006) demonstrated the potential to use selection to manipulate grazing distribution by separating cattle into hill-climber and bottom-dweller herds and comparing grazing patterns in similar paired pastures. Pastures grazed by bottom dwellers had less grazing on steep slopes and more grazing in riparian areas, while pasture grazed by hill climbers had more uniform utilization and less grazing in riparian areas.

For selection to be effective, we must determine the degree that nature and nurture affect grazing distribution. Howery et al. (1998) demonstrated that early experience as calves had a long-term effect on grazing distribution. Walker (1995) argued that the only way to change the grazing habits of livestock is through selection. Genetic selection has potential to dramatically improve a trait over time if the heritability is moderate or high (Falconer, 1981). Because greater selection pressure can be applied to bulls, genetic progress is greater through sire selection compared with culling undesirable cows. If traits are primarily affected by experience, culling undesirable cows is the only option for selection and progress is often slow because only a small percentage of the animals can be culled. The degree to which the genotype affects the phenotype (heritability) has traditionally been determined using population genetic techniques on cattle herds where the pedigree of each animal is known (Falconer, 1981). However, animal pedigrees are rarely known on extensive rangeland cattle operations. Recent advances in molecular genetics provide a novel approach for studying the genetic influence of traits that are difficult to measure on rangelands. Single nucleotide polymorphisms (SNPs) are single substitutions of one DNA base for another at a given location along the genome, which can be used as genetic markers. Genomic selection is based on genetic markers rather than animal pedigrees and has been adopted by the livestock industries to increase the accuracy of traditional estimated progeny differences (EPDs) of breeding values and to evaluate young sires with limited data from their offspring (Eggen, 2012). Currently, the adoption of this technology has been used for traits with intensive data collection processes. However, genomic selection is also useful for difficult-to-measure traits that cannot be practically selected for using traditional methods because the genotype can be determined directly rather than being estimated from phenotypic measurements and pedigree information (Eggen, 2012).

The Illumina Bovine High-Density SNP array evaluates approximately 770,000 genetic markers (i.e., SNP) across the 30 bovine chromosomes. This recently developed technology allows researchers to evaluate relationships between phenotypic traits and genetic markers at a much greater resolution than previously possible. The objective of this study was to determine if there were genetic markers associated with terrain use of cattle grazing mountainous and/or extensive rangeland pastures. The presence of quantitative trait locus (QTL) for terrain use in cattle would indicate that grazing distribution could be inherited.

Section snippets

Study Sites

Initially (first study), grazing distribution patterns of rangeland beef cattle were evaluated at five ranches and later (second study) cattle were tracked at two additional ranches. Terrain at the ranches was variable with some mountainous terrain and other pastures that were extensive with limited water (Table 1). Ranches with varying terrain and vegetation were specifically chosen for this study to ensure that any observed relationships between genetic markers and cattle grazing distribution

First Study—Genotypes from the Illumina BovineHD BeadChip

Significant QTL regions were detected on chromosomes 4, 17, and 29 for the rolling index (Table 3). A QTL on chromosome 4 accounted for 26% of the variation in the rolling index (Table 3). The ACN9 (ACN9 homolog) gene flanked the HD Marker (SNP used in the Illumina BovineHD BeadChip) located within 100.000 bp on chromosome 4. Also, two markers on chromosome 29 accounted for 11% and 15% of the variation in the rolling index, while a marker on chromosome 17 accounted for 13% of the variation in

Discussion

Multiple genetic markers were associated with both the rough and rolling indexes and explained from 10% to 24% of the phenotypic variation in the indexes of terrain use. These findings are exciting because most individual genetic markers account for only 1% or 2% of the phenotypic variation in a trait (DeAtley et al., 2011, Garrett et al., 2008, Luna-Nevarez et al., 2011).

One genetic marker on chromosome 29 was within exon 4 of the GMR5 gene that appears to be a factor in locomotion,

Management Implications

Cattle grazing distribution appears to be heritable. Bulls and replacement females with superior (or inferior) genotypes may potentially be identified with relatively inexpensive DNA tests rather than expensive GPS tracking or labor-intensive tracking by human observers. Genetic selection of cattle for spatial grazing behavior may be a viable management option in the near future, which may allow ranchers and land managers to improve grazing distribution without capital expenditures such as

Acknowledgments

We would like to thank Dr. Bart Carter and family (Carter Ranch), Erin and Dick Evans and family (Evans Ranch aka Heartstone Angus), Ray Hartley and family (Hartley Ranch), and Tom Todd and family (Todd Ranch) for the gracious and insightful cooperation in this study. We also appreciate the collaboration of the Calvin Bailey and Brian Samson of the Chihuahuan Desert Rangeland Research Center (College Ranch), Shad Cox and Richard Dunlap of the Corona Range and Livestock Research Center (Corona

References (48)

  • H.C. VanWagoner et al.

    Differences among beef sire breeds and relationships between terrain use and performance when daughters graze foothill rangelands as cows

    Applied Animal Behaviour Science

    (2006)
  • I.E. Zohn et al.

    p38 and a p38-interacting protein are critical for downregulation of E-cadherin during mouse gastrulation

    Cell

    (2006)
  • D.W. Bailey

    Management strategies for optimal grazing distribution and use of arid rangelands

    Journal of Animal Science

    (2004)
  • D.W. Bailey et al.

    Mechanisms that result in large herbivore grazing distribution patterns

    Journal of Range Management

    (1996)
  • D.W. Bailey et al.

    Relationship between terrain use and performance of beef cows grazing foothill rangeland

    Journal of Animal Science

    (2001)
  • D.W. Bailey et al.

    Research observation: daily movement patterns of hill climbing and bottom dwelling cows

    Journal of Range Management

    (2004)
  • D.W. Bailey et al.

    Genetic and environmental influences on distribution patterns of beef cattle grazing foothill rangeland

    Proceedings, Western Section American Society of Animal Science

    (2010)
  • D. Bailey et al.

    Relationship of temperament at calving and distribution of beef cows grazing foothill rangeland

  • M. Bayer et al.

    Identification and characterization of Iporin as a novel interaction partner for rab1

    BMC Cell Biology

    (2005)
  • A. Cánovas et al.

    Multi-tissue omics analyses reveal molecular regulatory networks for puberty in composite beef cattle

    PloS One

    (2014)
  • K.L. DeAtley et al.

    Genetic analyses involving microsatellite ETH10 genotypes on bovine chromosome 5 and performance trait measures in Angus- and Brahman-influenced cattle

    Journal of Animal Science

    (2011)
  • R.A. Dennis et al.

    Acn9 is a novel protein of gluconeogenesis that is located in the mitochondrial intermembrane space

    European Journal of Biochemistry

    (1999)
  • G. Dölen et al.

    Role for metabotropic glutamate receptor 5 (mGluR5) in the pathogenesis of fragile X syndrome

    The Journal of Physiology

    (2008)
  • A. Eggen

    The development and application of genomic selection as a new breeding paradigm

    Animal Frontiers

    (2012)
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    This project was funded by the USDA Western Sustainable Agriculture Research and Education Program (Western SARE) and the New Mexico Agricultural Experiment Station.

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