# Hoof Expansion, Deformation, and Surface Strains Vary with Horseshoe Nail Positions

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## Abstract

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## Simple Summary

## Abstract

## 1. Introduction

## 2. Materials and Methods

#### 2.1. Study Design

#### 2.2. Limb Specimens

#### 2.3. Limb Preparation

^{6}N/m) filled the solar surface of the hoof to the level of the weight bearing surface of the unshod or shod hoof. Nails were placed in the pre-existing holes for respective treatments. Due to the location of the hoof markers and strain gauges, the need to maintain the shoe in the same position on the hoof for all treatments, and the likelihood that driving nails in an instrumented hoof would detach the strain gauges from the hoof, the same nail holes were used from when the shoe was initially fitted for all nail treatments. Since the nails were removed and replaced according to the treatment order assignment for each limb, the nails were not clenched.

#### 2.4. Limb Instrumentation

#### 2.5. Mechanical Testing

#### 2.6. Data Reduction

#### 2.7. Statistical Analysis

## 3. Results

#### 3.1. Fetlock Extension

#### 3.2. Hoof Expansions

#### 3.3. Hoof Wall Deformations

#### 3.4. Hoof Strains

#### Principal Strains

#### 3.5. Principal Strain Directions

## 4. Discussion

^{6}N/m) and was less stiff than typical surfaces on which horses are generally worked (dirt approximately 1.65 × 10

^{5}N/m, synthetic approximately 2.64 × 10

^{5}N/m; unpublished data). The effect of the nail position (T, Q, or H) could not be separated from the effect of the number of nails applied (one, two, or three) because the addition of nails was only performed in the palmar direction. Finally, while there have been no studies, to our knowledge, on the effects of freezing on hoof tissue and its mechanical behavior compared to that of fresh tissue, we acknowledge that there is a potential for freezing and thawing to affect the results. However, since some of our results in strain and hoof expansion measurements do match those that were performed in live horse hooves, we are confident that the effects of freezing on the hoof are minimal.

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Limb instrumentation. (

**A**) Nail treatment locations that were used for a combination of toe (T), toe plus quarter (TQ), and toe plus quarter plus heel (TQH). (

**B**) Lateral view of the hoof instrumented with strain gauges, and the coordinate system for strain directions as well as where kinematic hoof markers were placed in relation to the strain gauges. Gauge positions are defined as proximal heel (PH), middle heel (MH), distal heel (DH), proximal quarter (PQ), middle quarter (MQ), and distal quarter (DQ). The 90/270° axis is along the tubules such that the 0/180° axis is perpendicular to the tubules. (

**C**) Lateral hoof wall segment definitions for defining lateral wall distortion: Proximal (Pr), distal (Di), dorsal (Do), palmar (Pa), proximodorsal to distopalmar (PrDo-DiPa), and proximopalmar to distodorsal (PrPa-DiDo). (

**D**) Schematic illustration of a palmar view of the instrumented limb with transfixation pins and kinematic markers used for measuring the fetlock angle and proximal and distal quarter and heel expansions.

**Figure 2.**The magnitudes and directions of tensile (

**A**), compressive (

**B**), and maximum shear (

**C**) principal strains are illustrated for each location and treatment on the lateral wall of a right hoof for proximal heel (PH), middle heel (MH), distal heel (DH), proximal quarter (PQ), middle quarter (MQ), and distal quarter (DQ) gauge placement.

**Figure 3.**Illustration of the findings associated with the TGH treatment on the lateral (

**A**) and palmar (

**B**) aspects of the foot that are consistent with the development of the underrun heel. Shortening of the Pa chord, principal tensile strain direction in the DQ gauge location, principal compressive strain direction in the MH gauge location, and principal shear strain direction in the MH and DH gauge locations are consistent with the dropping of the proximal aspect of the heel and the decreasing heel angle. A greater restriction of heel expansion at the proximal aspect of the heels than at the distal aspect of the heels drives the bulbs of the heels under the foot and subjects them to higher compressive forces.

**Table 1.**Heel and Hoof Wall Deformation by Load. Fetlock angle, hoof expansion, and wall deformation variables (least square means ± standard error) for 3600 N, 4600 N, and 6200 N loads, when averaged over all treatments. Within a row, values that do not share a superscript are statistically different at p < 0.05. p values are Type 3 tests of fixed effects for the load in the ANOVA model.

Variable | Load | p Value | ||
---|---|---|---|---|

3600 N | 4600 N | 6200 N | ||

FETLOCK EXTENSION | ||||

Fetlock angle (°) (n = 9) | 228 ^{a} ± 0.4 | 235 ^{b} ± 0.4 | 244 ^{c} ± 0.4 | <0.001 |

HOOF EXPANSION | ||||

Proximal heel (mm) (n = 9) | 0.22 ^{a} ± 0.21 | 0.53 ^{a} ± 0.21 | 1.22 ^{b} ± 0.21 | <0.0001 |

Distal heel (mm) (n = 9) | 0.35 ^{a} ± 0.08 | 0.65 ^{b} ± 0.08 | 1.33 ^{c} ± 0.08 | <0.0001 |

Proximal quarter (mm) (n = 8) | 0.25 ^{a} ± 0.08 | 0.37 ^{a,b} ± 0.08 | 0.52 ^{b} ± 0.08 | 0.009 |

Distal quarter (mm) (n = 8) | 0.13 ^{a} ± 0.05 | 0.21 ^{a} ± 0.05 | 0.32 ^{b} ± 0.05 | 0.007 |

WALL DEFORMATION | ||||

Pr (mm) (n = 7) | 0.12 ^{a} ± 0.04 | 0.17 ^{a} ± 0.04 | 0.28 ^{b} ± 0.04 | 0.0001 |

Di (mm) (n = 9) | 0.14 ^{a} ± 0.03 | 0.19 ^{a} ± 0.03 | 0.31 ^{b} ± 0.03 | <0.0001 |

Pa (mm) (n = 9) | 0.14 ^{a} ± 0.02 | 0.16 ^{a} ± 0.02 | 0.16 ^{a} ± 0.02 | 0.562 |

Do (mm) (n = 6) | 0.70 ^{a} ± 0.57 | 0.78 ^{a} ± 0.57 | 0.81 ^{a} ± 0.57 | 0.052 |

PrDo-DiPa (mm) (n = 7) | 0.47 ^{a} ± 0.38 | 0.62 ^{a} ± 0.38 | 0.66 ^{a} ± 0.38 | 0.168 |

PrPa-DiDo (mm) (n = 9) | 0.18 ^{a} ± 0.06 | 0.28 ^{a} ± 0.06 | 0.39 ^{b} ± 0.06 | <0.0001 |

**Table 2.**Heel and Hoof Wall Deformations by Treatment. Hoof expansion and wall deformation variables (least square means ± standard errors) for no shoe (NS), toe (T), toe plus quarter (TQ), and toe plus quarter plus heel (TQH) treatments, averaged over all loads. Within a row, values that do not share a superscript are statistically different at p < 0.05. p values are Type 3 tests of fixed effects for treatment in the ANOVA model. NA = These variables did not have NS included in the model, as the order was found to be significant in the statistical model.

Variable | Treatment | p Value | |||
---|---|---|---|---|---|

NS | T | TQ | TQH | ||

HOOF EXPANSION | |||||

Proximal heel (mm) (n = 9) | 1.02 ^{a} ± 0.23 | 0.91 ^{a} ± 0.23 | 0.63 ^{a} ± 0.23 | 0.06 ^{b} ± 0.23 | <0.0001 |

Distal heel (mm) (n = 9) | 1.03 ^{a} ± 0.08 | 0.86 ^{b} ± 0.08 | 0.71 ^{b} ± 0.08 | 0.53 ^{c} ± 0.08 | <0.0001 |

Proximal quarter (mm) (n = 8) | 0.28 ^{a} ± 0.09 | 0.45 ^{a,b} ± 0.09 | 0.55 ^{b} ± 0.09 | 0.25 ^{a} ± 0.09 | 0.002 |

Distal quarter (mm) (n = 8) | 0.27 ^{a,b} ± 0.06 | 0.30 ^{b} ± 0.06 | 0.16 ^{b,c} ± 0.06 | 0.16 ^{c} ± 0.06 | 0.0002 |

WALL DEFORMATION | |||||

Pr (mm) (n = 7) | NA | 0.17 ^{a} ± 0.04 | 0.21 ^{a} ± 0.04 | 0.19 ^{a} ± 0.04 | 0.410 |

Di (mm) (n = 9) | 0.26 ^{a} ± 0.03 | 0.17 ^{a} ± 0.03 | 0.21 ^{a} ± 0.03 | 0.20 ^{a} ± 0.03 | <0.0001 |

Pa (mm) (n = 9) | 0.19 ^{a} ± 0.02 | 0.14 ^{a,b} ± 0.02 | 0.17 ^{a,b} ± 0.02 | 0.11 ^{b} ± 0.02 | 0.041 |

Do (mm) (n = 6) | NA | 0.76 ^{a,b} ± 0.57 | 1.17 ^{a} ± 0.57 | 0.36 ^{b} ± 0.57 | 0.655 |

PrDo-DiPa (mm) (n = 7) | NA | 0.56 ^{a,b} ± 0.38 | 0.86 ^{a} ± 0.38 | 0.33 ^{b} ± 0.38 | 0.148 |

PrPa-DiDo (mm) (n = 9) | 0.34 ^{a} ± 0.06 | 0.30 ^{a} ± 0.06 | 0.27 ^{a} ± 0.06 | 0.24 ^{a} ± 0.06 | 0.251 |

**Table 3.**Principal Strains Least Squared Means for Load. Least Squared Means microstrain (µε) and standard error for strain magnitudes by load when averaged over all treatments. Within a row, values that do not share a superscript are statistically different at p < 0.05. p values are Type 3 tests of fixed effects for the load in the ANOVA model. Locations are defined as the proximal heel (PH), middle heel (MH), distal heel (DH), proximal quarter (PQ), middle quarter (MQ), and distal quarter (DQ) (Figure 1B).

Gauge | Load | p-Value | ||
---|---|---|---|---|

3600 N | 4600 N | 6200 N | ||

PRINCIPAL TENSILE STRAIN (µε) lsm ± se | ||||

PH (n = 9) | 238 ^{a} ± 53 | 173 ^{a,b} ± 53 | 62 ^{b} ± 53 | 0.0025 |

MH (n = 9) | 328 ^{a} ± 94 | 243 ^{a} ± 94 | −8 ^{b} ± 94 | 0.0018 |

DH (n = 9) | 1442 ^{a} ± 200 | 1486 ^{a} ± 200 | 1592 ^{a} ± 200 | 0.0295 |

PQ (n = 8) | 510 ^{a} ± 125 | 497 ^{b} ± 125 | 427 ^{b} ± 125 | 0.3263 |

MQ (n = 9) | 453 ^{a} ± 235 | 466 ^{a} ± 235 | 471 ^{a} ± 235 | 0.977 |

DQ (n = 9) | 948 ^{a} ± 125 | 988 ^{a} ± 125 | 1020 ^{a} ± 125 | 0.4352 |

PRINCIPAL COMPRESSIVE STRAIN (µε) lsm ± se | ||||

PH (n = 9) | −775 ^{a} ± 224 | −879 ^{a} ± 224 | −1197 ^{b} ± 224 | <0.0001 |

MH (n = 9) | −714 ^{a} ± 251 | −971 ^{a} ± 251 | −1633 ^{b} ± 251 | <0.0001 |

DH n = 9) | −1045 ^{a} ± 331 | −1143 ^{a,b} ± 331 | −1476 ^{a} ± 331 | 0.0132 |

PQ (n = 8) | −1353 ^{a} ± 414 | −1468 ^{a,b} ± 414 | −1689 ^{b} ± 414 | 0.0184 |

MQ (n = 9) | −994 ^{a} ± 199 | −1127 ^{b} ± 199 | −1445 ^{b} ± 199 | <0.0001 |

DQ (n = 9) | −557 ^{a} ± 214 | −558 ^{a} ± 214 | −608 ^{a} ± 214 | 0.9005 |

PRINCIPAL SHEAR STRAIN (µε) lsm ± se | ||||

PH (n = 9) | 1034 ^{a} ± 233 | 1103 ^{a} ± 233 | 1254 ^{a} ± 233 | 0.0728 |

MH (n = 9) | 1194 ^{a} ± 229 | 1399 ^{a} ± 299 | 1864 ^{b} ± 299 | 0.003 |

DH (n = 8) | 2460 ^{a} ± 386 | 2612 ^{a,b} ± 386 | 3073 ^{b} ± 386 | 0.0576 |

PQ (n = 9) | 2020 ^{a} ± 561 | 2108 ^{a} ± 561 | 2198 ^{a} ± 561 | 0.4815 |

MQ (n = 9) | 1453 ^{a} ± 239 | 1578 ^{a,b} ± 239 | 1887 ^{b} ± 239 | 0.0089 |

DQ (n = 8) | 1787 ^{a} ± 365 | 1849 ^{a} ± 365 | 1965 ^{a} ± 365 | 0.3716 |

**Table 4.**Principal Strains by Treatment. Principal strain magnitudes (least squared means ± standard errors) by nail treatment when averaged over all loads. Within a row, values that do not share a superscript are statistically different at p < 0.05. p values are Type 3 tests of fixed effects for treatment in the ANOVA model. NA = These variables did not have no shoe (NS) included in the model, as the order was found to be significant upon the initial testing of the model. Locations are defined as the proximal heel (PH), middle heel (MH), distal heel (DH), proximal quarter (PQ), middle quarter (MQ), and distal quarter (DQ) (Figure 1B).

Gauge | Treatment | p-Value | |||
---|---|---|---|---|---|

NS | T | TQ | TQH | ||

PRINCIPAL TENSILE STRAIN (µε) | |||||

PH (n = 9) | 115 ^{a} ± 56 | 233 ^{a} ± 56 | 147 ^{a} ± 56 | 136 ^{a} ± 61 | 0.1673 |

MH (n = 9) | 168 ^{a,b} ± 101 | 345 ^{a} ± 97 | 200 ^{a,b} ± 101 | 37 ^{b} ± 112 | 0.0674 |

DH (n = 9) | 1489 ^{a,b} ± 203 | 1395 ^{a} ± 200 | 1356 ^{a} ± 203 | 1788 ^{b} ± 220 | 0.0002 |

PQ (n = 8) | NA | 494 ^{a,b} ± 124 | 358 ^{a} ± 131 | 581 ^{b} ± 124 | 0.0081 |

MQ (n = 9) | NA | 538 ^{a} ± 236 | 270 ^{b} ± 234 | 582 ^{a} ± 236 | 0.0024 |

DQ (n = 9) | 741 ^{a} ± 128 | 893 ^{a,b} ± 125 | 1025 ^{b,c} ± 128 | 1282 ^{c} ± 134 | <0.0001 |

PRINCIPAL COMPRESSIVE STRAIN (µε) | |||||

PH (n = 9) | NA | −1045 ^{a} ± 223 | −715 ^{b} ± 223 | −1092 ^{a} ± 225 | <0.0001 |

MH (n = 9) | −1275 ^{a} ± 260 | −954 ^{a} ± 254 | −858 ^{a} ± 260 | −1338 ^{a} ± 276 | 0.068 |

DH (n = 9) | NA | −1011 ^{a} ± 327 | −1272 ^{a} ± 330 | −1382 ^{a} ± 346 | 0.0696 |

PQ (n = 8) | −1278 ^{a} ± 420 | −1627 ^{a} ± 415 | −1477 ^{a} ± 424 | −1632 ^{a} ± 415 | 0.0923 |

MQ (n = 9) | −929 ^{a} ± 202 | −899 ^{a,b} ± 204 | −1355 ^{b,c} ± 202 | −1571 ^{c} ± 204 | <0.0001 |

DQ (n = 9) | NA | −343 ^{a} ± 207 | −689 ^{b} ± 218 | −692 ^{a,b} ± 229 | 0.0201 |

MAXIMUM SHEAR STRAIN (µε) | |||||

PH (n = 9) | NA | 1343 ^{a} ± 231 | 929 ^{b} ± 234 | 1119 ^{a,b} ± 234 | 0.0005 |

MH (n = 9) | 1421 ^{a} ± 227 | 1378 ^{a} ± 246 | 1297 ^{a} ± 246 | 1846 ^{a} ± 278 | 0.2318 |

DH (n = 8) | NA | 2376 ^{a} ± 377 | 2646 ^{a,b} ± 383 | 3123 ^{b} ± 415 | 0.4052 |

PQ (n = 8) | NA | 2196 ^{a,b} ± 560 | 1865 ^{a} ± 566 | 2264 ^{b} ± 560 | 0.0449 |

MQ (n = 9) | 1290 ^{a} ± 241 | 1354 ^{a} ± 250 | 1629 ^{a} ± 245 | 2285 ^{b} ± 256 | <0.0001 |

DQ (n = 8) | NA | 1431 ^{a} ± 363 | 2235 ^{b} ± 366 | 1935 ^{b} ± 369 | <0.0001 |

**Table 5.**Principal Strain Directions Least Squared Means for Load. Least Squared Means Principal Strain directions (°) and standard error for strain directions by load when averaged over all treatments. Within a row, values that do not share a superscript are statistically different at p < 0.05. p values are Type 3 tests of fixed effects for the load in the ANOVA model. Locations are defined as the proximal heel (PH), middle heel (MH), distal heel (DH), proximal quarter (PQ), middle quarter (MQ), and distal quarter (DQ) (Figure 1B).

Gauge | Load | p-Value | ||
---|---|---|---|---|

3600 N | 4600 N | 6200 N | ||

PRINCIPAL TENSILE DIRECTION (°) lsm ± se | ||||

PH (n = 9) | 87 ^{a} ± 12 | 86 ^{a} ± 12 | 85 ^{a} ± 12 | 0.74 |

MH (n = 9) | 82 ^{a} ± 10 | 84 ^{a} ± 10 | 79 ^{a} ± 10 | 0.81 |

DH (n = 9) | 97 ^{a} ± 20 | 98 ^{a} ± 20 | 79 ^{a} ± 20 | 0.08 |

PQ (n = 8) | 83 ^{a} ± 5 | 82 ^{a} ± 5 | 81 ^{a} ± 5 | 0.87 |

MQ (n = 9) | 92 ^{a} ± 13 | 94 ^{a} ± 13 | 96 ^{a} ± 13 | 0.88 |

DQ (n = 9) | 121 ^{a} ± 19 | 118 ^{a} ± 19 | 119 ^{a} ± 19 | 0.96 |

PRINCIPAL COMPRESSIVE DIRECTION (°) lsm ± se | ||||

PH (n = 9) | 177 ^{a} ± 12 | 176 ^{a} ± 12 | 175 ^{a} ± 12 | 0.74 |

MH (n = 9) | 172 ^{a} ± 10 | 174 ^{a} ± 10 | 169 ^{a} ± 10 | 0.81 |

DH (n = 9) | 159 ^{a} ± 17 | 187 ^{a} ± 17 | 168 ^{a} ± 17 | 0.11 |

PQ (n = 8) | 173 ^{a} ± 5 | 172 ^{a} ± 5 | 171 ^{a} ± 5 | 0.92 |

MQ (n = 9) | 182 ^{a} ± 13 | 184 ^{a} ± 13 | 186 ^{a} ± 13 | 0.88 |

DQ (n = 9) | 211 ^{a} ± 19 | 208 ^{a} ± 19 | 209 ^{a} ± 19 | 0.96 |

PRINCIPAL SHEAR DIRECTION (°) lsm ± se | ||||

PH (n = 9) | 132 ^{a} ± 12 | 131 ^{a} ± 12 | 130 ^{a} ± 12 | 0.74 |

MH (n = 9) | 127 ^{a} ± 10 | 129 ^{a} ± 10 | 124 ^{a} ± 10 | 0.81 |

DH (n = 9) | 142 ^{a} ± 20 | 143 ^{a} ± 20 | 124 ^{a} ± 20 | 0.08 |

PQ (n = 8) | 127 ^{a} ± 6 | 127 ^{a} ± 6 | 121 ^{a} ± 6 | 0.37 |

MQ (n = 9) | 137 ^{a} ± 13 | 139 ^{a} ± 13 | 141 ^{a} ± 13 | 0.88 |

DQ (n = 9) | 166 ^{a} ± 19 | 163 ^{a} ± 19 | 164 ^{a} ± 19 | 0.96 |

**Table 6.**Principal Strain Directions Least Squared Means ± Standard Errors. Principal strain directions (least squared means ± standard errors) by nail treatment (no shoe (NS), toe (T), toe plus quarter (TQ), and toe plus quarter plus heel (TQH)), when averaged over all loads. Within a row, values that do not share a superscript are statistically different at p < 0.05. p values are Type 3 tests of fixed effects for treatment in the ANOVA model. NA = These variables did not have NS included in the model, as the order was found to be significant upon the initial testing of the model. Locations are defined as the proximal heel (PH), middle heel (MH), distal heel (DH), proximal quarter (PQ), middle quarter (MQ), and distal quarter (DQ) (Figure 1B).

Gauge | Treatment | p-Value | |||
---|---|---|---|---|---|

NS | T | TQ | TQH | ||

PRINCIPAL TENSILE DIRECTION (°) lsm ± se | |||||

PH (n = 9) | 75 ^{a} ± 12 | 86 ^{b} ± 12 | 85 ^{b} ± 12 | 97 ^{c} ± 13 | <0.0001 |

MH (n = 9) | 58 ^{a} ± 10 | 67 ^{a} ± 11 | 69 ^{a} ± 11 | 132 ^{b} ± 13 | <0.0001 |

DH (n = 9) | 80 ^{a} ± 20 | 86 ^{a,b} ± 20 | 83 ^{a,b} ± 20 | 115 ^{b} ± 21 | 0.053 |

PQ (n = 8) | NA | 75 a ± 5 | 85 ^{b} ± 5 | 86 ^{b} ± 5 | 0.002 |

MQ (n = 9) | 56 ^{a} ± 13 | 101 ^{b} ± 14 | 105 ^{b} ± 13 | 114 ^{b} ± 14 | <0.0001 |

DQ (n = 9) | 102 ^{a} ± 19 | 106 ^{a} ± 19 | 104 ^{a} ± 21 | 166 ^{b} ± 24 | 0.031 |

PRINCIPAL COMPRESSIVE DIRECTION (°) lsm ± se | |||||

PH (n = 9) | 165 ^{a} ± 12 | 176 ^{b} ± 12 | 175 ^{b} ± 12 | 187 ^{c} ± 13 | <0.0001 |

MH (n = 9) | 148 ^{a} ± 10 | 157 ^{a} ± 11 | 159 ^{a} ± 11 | 222 ^{b} ± 13 | <0.0001 |

DH (n = 9) | 173 ^{a,b} ± 18 | 146 ^{a} ± 17 | 170 ^{a,b} ± 18 | 197 ^{b} ± 21 | 0.045 |

PQ (n = 8) | NA | 165 ^{a} ± 5 | 175 ^{b} ± 5 | 176 ^{b} ± 5 | 0.002 |

MQ (n = 9) | 146 ^{a} ± 13 | 191 ^{b} ± 14 | 195 ^{b} ± 13 | 204 ^{b} ± 14 | <0.0001 |

DQ (n = 9) | 192 ^{a} ± 19 | 196 ^{b} ± 19 | 194 ^{b} ± 21 | 256 ^{b} ± 24 | 0.031 |

PRINCIPAL SHEAR DIRECTION (°) lsm ± se | |||||

PH (n = 9) | 120 ^{a} ± 12 | 131 ^{b} ± 12 | 130 ^{b} ± 12 | 142 ^{c} ± 13 | <0.0001 |

MH (n = 9) | 103 ^{a} ± 10 | 112 ^{a} ± 11 | 114 ^{a} ± 11 | 177 ^{b} ± 13 | <0.0001 |

DH (n = 9) | 125 ^{a} ± 20 | 131 ^{a} ± 20 | 128 ^{a} ± 20 | 160 ^{a} ± 21 | 0.053 |

PQ (n = 8) | NA | 120 ^{a} ± 6 | 125 ^{a} ± 6 | 131 ^{a} ± 6 | 0.080 |

MQ (n = 9) | 101 ^{a} ± 13 | 146 ^{b} ± 14 | 150 ^{b} ± 13 | 159 ^{b} ± 14 | <0.0001 |

DQ (n = 9) | 147 ^{a} ± 19 | 151 ^{a} ± 19 | 149 ^{a} ± 21 | 211 ^{b} ± 24 | 0.031 |

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## Share and Cite

**MDPI and ACS Style**

Dahl, V.E.; Singer, E.R.; Garcia, T.C.; Hawkins, D.A.; Stover, S.M.
Hoof Expansion, Deformation, and Surface Strains Vary with Horseshoe Nail Positions. *Animals* **2023**, *13*, 1872.
https://doi.org/10.3390/ani13111872

**AMA Style**

Dahl VE, Singer ER, Garcia TC, Hawkins DA, Stover SM.
Hoof Expansion, Deformation, and Surface Strains Vary with Horseshoe Nail Positions. *Animals*. 2023; 13(11):1872.
https://doi.org/10.3390/ani13111872

**Chicago/Turabian Style**

Dahl, Vanessa E., Ellen R. Singer, Tanya C. Garcia, David A. Hawkins, and Susan M. Stover.
2023. "Hoof Expansion, Deformation, and Surface Strains Vary with Horseshoe Nail Positions" *Animals* 13, no. 11: 1872.
https://doi.org/10.3390/ani13111872