Phylogeny and geographical distribution of the Family Equidae with the three subfamilies; Equinae (visualised by its two tribes; Equini and Hipparionini), 'Hyracotherinae' and Anchitheriinae. Colours indicate the digit count of the forelimb (blue = tetradactyl, purple = tridactyl, pink = monodactyl). Only the names of the monodactyl genera are displayed in the figure. Based on MacFadden (2005).

Contexts in source publication

Context 1

... these three perissodactyl families, only the Equidae underwent a strong digit reduction in both the fore-and hindlimb through their evolution (Azzaroli, 1992). The Equinae, 'Hyracotherinae' and Anchitheriinae are the three subfamilies within the Equidae (Mihlbachler et al., 2011) (Figure 1). The extreme digit reduction towards a fully anatomical monodactyl limb is found only within the Equinae subfamily, and only then within the tribe Equini (Janis & Bernor 2019). ...

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... extreme digit reduction towards a fully anatomical monodactyl limb is found only within the Equinae subfamily, and only then within the tribe Equini (Janis & Bernor 2019). The members of the subfamilies 'Hyracotherinae' and Anchitheriinae remained tetra-or tridactyl (MacFadden, 1992(MacFadden, , 2005Janis, 2007;Solounias et al., 2018;Janis and Bernor, 2019) (Figure 1). The earliest tetradactyl ancestors of the modern horses are considered to be Sifrhippus and Eohippus. ...

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... Dinohippus, Hippidion) tribes ( Janis and Bernor, 2019). In the equinines, the first anatomically monodactyl horse genera evolved within three genera in the late Miocene (c. 5 Mya); the Pliohippus, Astrohippus and Dinohippus lineages (MacFadden, 1984) (Figure 1). From these genera, it is MacFadden (2005). ...

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... with the discovery of more Equidae fossils, this image began to shift. The evolution of horses is not simply a linear line, but appears to be much more complex and the phylogeny is better described as an intricate bush with multiple branches ( Figure 1) (Simpson, 1951;MacFadden, 1992MacFadden, , 2005. Within this complex evolution, some lineages did increase in body size (following Cope's rule; MacFadden 1986) in the same way as Marsh's sequence of equids. ...

Context 5

... schematic overview of the successive steps is shown in Figure 1. Table 1 presents an overview (with reference to Figure 1) of the corresponding workflow to obtain joint constraints based on the manipulation experiments. ...

Context 6

... schematic overview of the successive steps is shown in Figure 1. Table 1 presents an overview (with reference to Figure 1) of the corresponding workflow to obtain joint constraints based on the manipulation experiments. The numbers in the first column refers to the paragraphs, in which the workflow is explained in more detail below. ...

Context 7

... anatomical markers are transformed to 'virtual anatomical markers' in each frame of the recordings of the manipulation experiments using the marker triads in both the dynamic recordings of the manipulation experiments and in the static recording, as well as the defined position (see step 4) of the anatomical markers relative to the marker triad. 6. Defining an anatomically relevant local coordinate system ( Figure 1G) Using the transformed anatomical marker triads (i.e. 'virtual anatomical markers') in the motion data, an anatomically relevant local coordinate system (LCS) for each of the forelimb segments is defined for all frames in the motion data. ...

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... anatomical markers') in the motion data, an anatomically relevant local coordinate system (LCS) for each of the forelimb segments is defined for all frames in the motion data. 7. Calculating the joint angles ( Figure 1H) for each rotational degree of freedom and their associated range of motion. ...

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... the minimal and maximal joint angles, the range of motion is calculated for each rotational degree of freedom. 8. Calculating the finite helical axis ( Figure 1H) ...

Context 10

... an infra-red camera system, each camera has its own infra-red-source and receiver, and (ideally) captures only the light reflected by the reflective markers on the object of interest. Since each camera obtains a 2D view on the volume of interest, multiple cameras are placed at different heights and at different angles around the recording area (Figures 1-2).When a marker is seen by at least two cameras, multiple 2D images can be combined into 3D real world trajectories of the markers (i.e. marker coordinates in the global coordinate system; GCS), provided the system is calibrated first. ...

Context 11

... present the position and orientation of the FHA, the intersection of the FHA with the reference planes of the LCS of the proximal segment (i.e. planes of motion) for each position-interval can be determined (see Figure 10). The coordinates of the intersections with the sagittal plane are used to express the position of the FHA during FE, with the frontal plane for AA, and transverse plane for IE manipulation experiments ( Figure 10B-D). ...

Context 12

... of motion) for each position-interval can be determined (see Figure 10). The coordinates of the intersections with the sagittal plane are used to express the position of the FHA during FE, with the frontal plane for AA, and transverse plane for IE manipulation experiments ( Figure 10B-D). The position of the axis is described with respect to the origin of the proximal LCS; i.e. the proximo-distal (PD-) distance, the craniocaudal or dorso-palmar (CC/DP-) distance, and the medio-lateral (ML-) distance ( Figure 10B-D). ...

Context 13

... coordinates of the intersections with the sagittal plane are used to express the position of the FHA during FE, with the frontal plane for AA, and transverse plane for IE manipulation experiments ( Figure 10B-D). The position of the axis is described with respect to the origin of the proximal LCS; i.e. the proximo-distal (PD-) distance, the craniocaudal or dorso-palmar (CC/DP-) distance, and the medio-lateral (ML-) distance ( Figure 10B-D). The orientation of the FHA is described by means of projection angles ( Figure 10E-G). ...

Context 14

... position of the axis is described with respect to the origin of the proximal LCS; i.e. the proximo-distal (PD-) distance, the craniocaudal or dorso-palmar (CC/DP-) distance, and the medio-lateral (ML-) distance ( Figure 10B-D). The orientation of the FHA is described by means of projection angles ( Figure 10E-G). In total three angles can be defined: (i) the 'inclination' angle, defined as the angle between the projections of the FHA in the sagittal plane and the proximo-distal axis of the LCS (van den Bogert et al., 2008; Figure 10E), (ii) the frontal angle is defined as the angle between the projections of the FHA in the frontal plane and the proximo-distal axis of the LCS ( Figure 10F) and (iii) the 'deviation' angle, defined as the angle between the projections of the FHA onto the transverse plane and the medio-lateral axis of the LCS (van den Bogert et al., 2008; Figure 10G). ...

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... orientation of the FHA is described by means of projection angles ( Figure 10E-G). In total three angles can be defined: (i) the 'inclination' angle, defined as the angle between the projections of the FHA in the sagittal plane and the proximo-distal axis of the LCS (van den Bogert et al., 2008; Figure 10E), (ii) the frontal angle is defined as the angle between the projections of the FHA in the frontal plane and the proximo-distal axis of the LCS ( Figure 10F) and (iii) the 'deviation' angle, defined as the angle between the projections of the FHA onto the transverse plane and the medio-lateral axis of the LCS (van den Bogert et al., 2008; Figure 10G). Determining the positions and angles for all consecutive intervals of the ROM thus enables the description of the displacement and reorientation of the FHA during the manipulations. ...

Context 16

... orientation of the FHA is described by means of projection angles ( Figure 10E-G). In total three angles can be defined: (i) the 'inclination' angle, defined as the angle between the projections of the FHA in the sagittal plane and the proximo-distal axis of the LCS (van den Bogert et al., 2008; Figure 10E), (ii) the frontal angle is defined as the angle between the projections of the FHA in the frontal plane and the proximo-distal axis of the LCS ( Figure 10F) and (iii) the 'deviation' angle, defined as the angle between the projections of the FHA onto the transverse plane and the medio-lateral axis of the LCS (van den Bogert et al., 2008; Figure 10G). Determining the positions and angles for all consecutive intervals of the ROM thus enables the description of the displacement and reorientation of the FHA during the manipulations. ...

Context 17

... orientation of the FHA is described by means of projection angles ( Figure 10E-G). In total three angles can be defined: (i) the 'inclination' angle, defined as the angle between the projections of the FHA in the sagittal plane and the proximo-distal axis of the LCS (van den Bogert et al., 2008; Figure 10E), (ii) the frontal angle is defined as the angle between the projections of the FHA in the frontal plane and the proximo-distal axis of the LCS ( Figure 10F) and (iii) the 'deviation' angle, defined as the angle between the projections of the FHA onto the transverse plane and the medio-lateral axis of the LCS (van den Bogert et al., 2008; Figure 10G). Determining the positions and angles for all consecutive intervals of the ROM thus enables the description of the displacement and reorientation of the FHA during the manipulations. ...

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... determine whether all steps of the analysis script worked properly, we performed a validation experiment. We designed an artificial joint consisting of two wooden blocks connected to each other with a door hinge ( Figure 11). For this artificial joint the position of the FHA was known: the position of the door hinge was measured by two markers on the sides of the hinge. ...

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... artificial joint was manipulated through its full ROM, simulating the same situation as with the cadaveric forelimbs. The FHA was calculated as described above and the results of the validation test are shown in Figure 12. As can be seen in Figure 12, when the artificial joint gets close to its maximal joint angle (~180⁰) the analysis code is not able to accurately calculate the FHA. ...

Context 20

... FHA was calculated as described above and the results of the validation test are shown in Figure 12. As can be seen in Figure 12, when the artificial joint gets close to its maximal joint angle (~180⁰) the analysis code is not able to accurately calculate the FHA. The reason for this is that close to 180⁰ the analysis code cannot find the next frame with approximately +5⁰ (window size) in order to accurately calculate a FHA. ...

Context 21

... on the results of the validation test, the outliers close to the maximal joint angles obtained from the manipulation experiments were removed from the analysis. [Note that in the results of the validation ( Figure 12) the y-position changed in position, because the proximal segment was not fixed at a certain height during the validation trail.] Figure 11. Photographs of the artificial joint, the tracking markers of the proximal (PT1-3) and distal (D1-3) segment and anatomical markers of the proximal (AP1-4) and distal (AD1-4) segment. ...

Context 22

... that in the results of the validation ( Figure 12) the y-position changed in position, because the proximal segment was not fixed at a certain height during the validation trail.] Figure 11. Photographs of the artificial joint, the tracking markers of the proximal (PT1-3) and distal (D1-3) segment and anatomical markers of the proximal (AP1-4) and distal (AD1-4) segment. ...

Context 23

... left forelimb was removed from the trunk by cutting the soft tissues between the scapula and the rib cage. Six forelimb segments were defined, from proximal to distal, the shoulder, brachium, antebrachium, metacarpus, pastern and hoof ( Figure 1). To ensure that all anatomically possible positions and orientations of the distal segment with respect to the proximal segment in each joint were obtained and to maximize the ROM, standardized cuts through the soft tissue were made midway along the length of each forelimb segment to eliminate muscle, tendon, fascia and skin stiffness ( Figure 1). ...

Context 24

... forelimb segments were defined, from proximal to distal, the shoulder, brachium, antebrachium, metacarpus, pastern and hoof ( Figure 1). To ensure that all anatomically possible positions and orientations of the distal segment with respect to the proximal segment in each joint were obtained and to maximize the ROM, standardized cuts through the soft tissue were made midway along the length of each forelimb segment to eliminate muscle, tendon, fascia and skin stiffness ( Figure 1). Joint capsules, tendon attachment sites and ligaments surrounding the joint were kept intact. ...

Context 25

... capsules, tendon attachment sites and ligaments surrounding the joint were kept intact. A bone-pin was drilled into the shaft of the main bone of each segment: scapula (shoulder), humerus (brachium), fused radius and ulna (radio-ulna) (antebrachium), third metacarpal bone (metacarpus), proximal phalanx (pastern) and distal phalanx via the hoof wall (PIP-DIP joints) ( Figure 1). Reflective marker triads with a marker diameter of 15 mm, were attached to the bone pins. ...

Context 26

... secure attachment of the marker triads ensured that they represented the exact movements of the bones to which they were attached. The joints were, from proximal to distal, the shoulder, elbow, carpus, fetlock and PIP-DIP joints, which included the proximal and distal interphalangeal joints ( Figure 1). The FHA of the distal sesamoid bones were not tracked in this study. ...

Context 27

... from the dynamic trials, for each type of rotation, were used to determine the minimal and maximal joint angle and the ROM for each rotational DOF. Joint angles were calculated using the neutral positions of the forelimb joints as reported in Weller et al 2006, (Figure 1). During the quality control, trials were removed from the data set when for example bone pins appeared to be loose, misplacement of the anatomical markers led to untenable joint angles or when the out of plane motion showed large deviations when testing for a certain rotational DOF. ...

Context 28

... helical axis was calculated using the finite helical axis method ( Woltring et al., 1985) for six forelimb joints in the monodactyl species namely, shoulder, elbow, carpus, fetlock and the digital joints (proximal and distal interphalangeal joints combined; PIP-DIP joints, see Figure 1 in Kaashoek et al., 2019). Only the proximal joints (shoulder and elbow) were measured in the alpaca, dog, lion, snow leopard, takin and tapir. ...

Context 29

... angles were used to describe the orientation of the FHA; the deviation angle (the angle between the FHA projected onto the transverse plane and the medio-lateral axis), the inclination angle (the angle between the FHA projected onto the sagittal plane and the proximo-distal axis) and the frontal angle (the angle between the FHA projected onto the frontal plane and the proximo-distal axis). The position was given using the proximo-distal and cranio-caudal/dorso-palmar distances as defined by the intersections of the FHA with the sagittal plane at the level of the distal joint centre of the proximal segment (see Figure 12 Chapter 1 in this thesis). As reported in Kaashoek et al. (2019), a significant effect of the direction of movement (extending versus flexing the joint) on the FHA properties was only found in four out of twenty cases, therefore the direction of movement in the manipulation experiments was not taken into account in the statistical analysis of the current study. ...

Context 30

... the first part of the analysis the equine data set (domestic horses of varying sizes, Przewalski's horse, and Hartmann's zebra) was used to determine the effect of size and/or ROM-parts on the FHA properties (deviation angle, inclination angle, frontal angle, proximo-distal and craniocaudal/dorso-palmar distance) for the modern equids. A schematic overview of the decision tree to determine which analysis was used and which result was calculated is shown in Figure 1. ...

Context 31

... FHA changed with joint angle as reported in Kaashoek et al. (2019): For each FHA property that changed significantly with joint angle (Table 2), as reported in Kaashoek et al. (2019) for the domestic horses, a multivariate analysis of covariance (MANCOVA) was performed to determine if size had a significant effect on the FHA property while taking the ROM-parts into account (Figure 1). The FHA variables that changed with joint angle were used as the dependent variable in the MANCOVA, size (i.e. one of the bone measures; see further) was defined as the covariate, and the ROM-parts were defined as the fixed factor in the statistical test. ...

Context 32

... types of results were calculated, based on the outcome of the MANCOVA (see right hand side, Figure 1). If the FHA property significantly changed with size (blue arrows, upper half of Figure 1), a reduced major axis regression was calculated, and its equation was reported to describe the relationship between size and the FHA property. ...

Context 33

... types of results were calculated, based on the outcome of the MANCOVA (see right hand side, Figure 1). If the FHA property significantly changed with size (blue arrows, upper half of Figure 1), a reduced major axis regression was calculated, and its equation was reported to describe the relationship between size and the FHA property. If the FHA property did not change with size, a mean value of the FHA property was calculated for all equids combined using the mean (Table 2), a mean value of the FHA variable was calculated over the entire ROM (orange arrow, lower half of Figure 1). ...

Context 34

... the FHA property significantly changed with size (blue arrows, upper half of Figure 1), a reduced major axis regression was calculated, and its equation was reported to describe the relationship between size and the FHA property. If the FHA property did not change with size, a mean value of the FHA property was calculated for all equids combined using the mean (Table 2), a mean value of the FHA variable was calculated over the entire ROM (orange arrow, lower half of Figure 1). A linear regression was performed to determine whether the FHA property changed significantly with size (i.e. one of the bone measures) (blue arrow, lower half of Figure 1). ...

Context 35

... the FHA property did not change with size, a mean value of the FHA property was calculated for all equids combined using the mean (Table 2), a mean value of the FHA variable was calculated over the entire ROM (orange arrow, lower half of Figure 1). A linear regression was performed to determine whether the FHA property changed significantly with size (i.e. one of the bone measures) (blue arrow, lower half of Figure 1). If a significant change with size (i.e. a significant P-value for the slope of the linear regression) was found, then the regression describing the relationship between the FHA property and size was reported. ...

Context 36

... overview of the overall minimal and maximal joint angles and the ROM values of the three rotational DOFs, calculated over all horses used in this study, can be found in Kaashoek et al. (2019). As can be seen in Figure 1-5A, all joints display a complex 3D interaction between the three rotational DOFs, with movements in all three rotational DOFs. Flexionextension showed the largest ROM of all rotational DOFs for all joints. ...

Context 37

... the individual variation, we visually compared the different horses based on the graphs. As can be seen in Figures 1-5, in most joints individual variation between the horses is observed. For all joints, the largest variation between individuals was found for the AA and IE interactions (Figures 1-5D). ...

Context 38

... can be seen in Figures 1-5, in most joints individual variation between the horses is observed. For all joints, the largest variation between individuals was found for the AA and IE interactions (Figures 1-5D). For the shoulder (Figure 1) and PIP-DIP joints there was a clear overlap of the interactions between the rotational DOFs for the different individuals. ...

Context 39

... all joints, the largest variation between individuals was found for the AA and IE interactions (Figures 1-5D). For the shoulder (Figure 1) and PIP-DIP joints there was a clear overlap of the interactions between the rotational DOFs for the different individuals. For the elbow and fetlock, parts of the interaction between FE-AA and FE-IE are very similar for all horses. ...

Context 40

... the direction of movement, we visually compared the ascending (moving from flexion to extension, dashed lines in Figure 1-5) and descending (moving from extension to flexion, dotted lines in Figures 1-5) joint angle phases of the movement cycle displayed in Figure 1-5. For the elbow (Figure 2) and the fetlock (Figure 4) we observed that the difference between the ascending and descending joint angle phase of an individual was relatively small. ...

Context 41

... the direction of movement, we visually compared the ascending (moving from flexion to extension, dashed lines in Figure 1-5) and descending (moving from extension to flexion, dotted lines in Figures 1-5) joint angle phases of the movement cycle displayed in Figure 1-5. For the elbow (Figure 2) and the fetlock (Figure 4) we observed that the difference between the ascending and descending joint angle phase of an individual was relatively small. ...

Context 42

... the direction of movement, we visually compared the ascending (moving from flexion to extension, dashed lines in Figure 1-5) and descending (moving from extension to flexion, dotted lines in Figures 1-5) joint angle phases of the movement cycle displayed in Figure 1-5. For the elbow (Figure 2) and the fetlock (Figure 4) we observed that the difference between the ascending and descending joint angle phase of an individual was relatively small. ...

Context 43

... ascending and descending joint angle phase of the carpus and PIP-DIP joints were visibly different but much less than in the shoulder. The difference between the ascending and descending phase was most obvious for the shoulder (Figure 1). ...

Context 44

... this explorative chapter our main focus was to visualise the complexity of the 3D interactions between the rotational DOFs in the equine forelimb joints. As can be seen in Figures 1-5, each joint displayed a certain complexity of the interactions between the three rotational DOFs. Due to this complexity we based our findings on visual observations. ...

Context 45

... Kaashoek et al. (2019) a significant linear correlation was found between FE-AA for all forelimb joints. As can be seen in Figure 1-5C, in the current study, all joints show a clear change of the abduction-adduction angle with flexion-extension angle, indicating a strong coupling between these two rotational DOFs. In the study of Kaashoek et al. (2019) a significant linear correlation between FE-IE for the elbow and fetlock was also found. ...

Context 46

... can be seen in Figure 2B and 4B, the interaction between FE-IE appears to be linear for elbow and fetlock of the individual horses. For the FE-IE interactions for the shoulder, carpus and PIP-DIP joints these interactions appear less linear ( Figure 1B,3B,5B), which explains why there was no linear correlation found in Kaashoek et al. (2019) for the FE-IE relationship for these joints. There was still a clear coupling between these rotational DOFs, but this relationship could potentially be better described using a polynomial fit instead of a linear fit. ...

Context 47

... interaction between AA-IE was not studied in Kaashoek et al. (2019). But as can be seen from Figure 1-5D, the shape of the interaction between these two rotational DOFs was less distinct which could be due to the smaller ROM of both abductionadduction and internal-external rotation. Note that the linear correlations in the previous study of Kaashoek et al. (2019) were calculated over all horses as a species but, as can be seen in, for example, the FE-AA interactions of the carpus, some individuals do not display a linear relationship between the two rotational DOFs. ...

Context 48

... the current study the PIP and DIP joints were measured simultaneously, because certain studies regarding the locomotion of horses define the proximal phalanx (long pastern) and middle phalanx (short pastern) as a single segment (van Weeren et al., 1993;Back et al., 1995;Galisteo et al., 2001). The PIP-DIP joints are both saddle joints and need to be able to show larger out of sagittal plane motion and more freedom of motion compared to the fetlock and elbow, because these joints compensate when the hooves are placed on an uneven surface (Budras et al., 2012), the PIP-DIP joints thus need a more motion freedom compared to the elbow and fetlock. ...

Context 49

... animals were used partly because obtaining a high number of donkey and zebra cadavers proved to be difficult, but also because it enabled us to determine the inertial properties in a standardized manner for different animals without having to weigh them. For the horses, prior to the photographs the height of the withers was measured using a special scale as can be seen in Figure 1. The forelimb of each subject was photographed orthogonal to the forelimb, in the lateral and frontal view, while the animals were standing straight (i.e. ...

Context 50

... lines indicate the regressions with the 95% confidence interval. Table 5 and Figure 10 show the results of the MANCOVA which was used to test if there was a significant difference between the species for the MOIt, while taking size into account, for the different forelimb segments. All forelimb segments showed a significant change of the MOIt with size (i.e. ...

Context 51

... hoof was the only segment that showed a significant interaction effect of species and length (PS*L = 0.01) and the RMA regressions for each species separately are shown in Table 5. As can be seen in Figure 10, the increase of MOIt with segmental length for the hoof of the zebra was less steep compared to the other species. Figure 10. ...

Context 52

... can be seen in Figure 10, the increase of MOIt with segmental length for the hoof of the zebra was less steep compared to the other species. Figure 10. Results of the log-log relationship between the segmental length (m) and MOIt ((kg m -2 ) 1/5 ) for the forelimb segments: brachium, antebrachium, metacarpus, pastern and hoof. ...

Context 53

... lateral angle of all the forelimb segments were not affected by size and did not significantly differ between species, therefore mean values were calculated over all species using the raw, untransformed data. The brachium showed a mean lateral angle of 116 ± 6.12 degrees, the antebrachium of 176 ± 3.40 degrees, the metacarpus of 177 ± 3.78 degrees, the pastern had an angle of 207 ± 5.42 degrees and the hoof of 211 ± 10.53 degrees (Figure 11). ...

Context 54

... results of the ANCOVA and the relationships between segmental length and total limb length (i.e. sum of all the segmental lengths) are displayed in Table 7 and Figure 12. With this analysis the effect of size and species on the forelimb proportions (i.e. ...

Context 55

... that the number of individuals used for the zebras was possibly not enough to properly calculate a lower and upper confidence interval. As can be seen in Figure 12, for the antebrachium, the donkeys and zebras had a similar relationship between the segmental lengths and the total limb. The horses showed a steeper increase of segmental length with total limb length for the antebrachium. ...

Context 56

... zebras were the only species that showed a decrease in hoof segmental length with increasing total limb length. Figure 12. Results of the log-log relationship between the forelimb segmental length (m) and the total limb length (m) for the forelimb segments: brachium, antebrachium, metacarpus, pastern and hoof. ...

Context 57

... hoof was the only segment that differed between the species for the masst and MOIt. Based on the regressions for the different species (Figure 8 and 10), we found that the relationship between the hoof masst and hoof length, and the relationships between the hoof MOIt and the hoof length differed between the species. The horses had a steeper increase of the hoof MOIt with segmental length compared to the donkeys and zebras. ...

Context 58

... trimming the hoof, angle and hoof length are adjusted, among others, to reduce the strain on the hoof wall ( Back and Clayton, 2013). In donkeys the hooves are trimmed at a steeper angle (55° in donkeys and 47° in horses) ( Figure 13). Also the frequency between the times of trimming varies between the species used in this study, zebra's in the zoo only get trimmed yearly while horses generally get trimmed every 8 weeks and donkeys in general every 8-10 weeks (Back and Clayton, 2013). ...

Context 59

... in the previous study they used segmental mass as a measure for size and in their research paper they did not report the mass to segmental length relationships. Figure 15 shows the calculated segmental masses versus the segmental length of the current study and the measured segmental masses versus the segmental lengths of Nauwelaerts et al. (2011). As can be seen in Figure 15, different relationships between segmental mass and segmental length were found for the two studies. ...

Context 60

... 15 shows the calculated segmental masses versus the segmental length of the current study and the measured segmental masses versus the segmental lengths of Nauwelaerts et al. (2011). As can be seen in Figure 15, different relationships between segmental mass and segmental length were found for the two studies. ...

Context 61

... the study of Nauwelaerts et al. (2011) they used cadaver limbs and were able to disarticulate the segments at the joints and obtain a more precise segment definition. Differences in segment definition ( Figure 16) between the current study and the study of Nauwelaerts et al. (2011) could have resulted in differences in the relationships between mass and length of the forelimb segments as shown in Figure 15. There were also some differences between the breeds used in the current study and the breeds used in the study of Nauwelaerts et al. (2011). ...

Context 62

... the study of Nauwelaerts et al. (2011) they used cadaver limbs and were able to disarticulate the segments at the joints and obtain a more precise segment definition. Differences in segment definition ( Figure 16) between the current study and the study of Nauwelaerts et al. (2011) could have resulted in differences in the relationships between mass and length of the forelimb segments as shown in Figure 15. There were also some differences between the breeds used in the current study and the breeds used in the study of Nauwelaerts et al. (2011). ...

Context 63

... study included Shetland ponies while in the previous study of Nauwelaerts et al. (2011) miniature horses and Hackley ponies were used. As can be seen in Figure 15, the measured segmental length and segmental masses in the study of Nauwelaerts et al. (2011) had a smaller range of segmental lengths compared to that of our study. In our study, the Shetland ponies and donkeys were the smallest equids measured and they influenced the orientation of the regression. ...

Context 64

... in the metacarpus circumference could lead to variation in the segmental mass between breeds. Figure 17 shows the mass and segmental length data of the metacarpus of the individual horse breeds used in this study. As can be seen, the warmblood horses were in line with the overall regression as well as the Shetland ponies. ...

Context 65

... joint, compound and ball and socket joint). A visual summary of the results of Chapter 2 and 3 is displayed in Figure 1. ...

Context 66

... Table 6). Figure 1. Overview of the different forelimb bones, for each bone the frontal view on the right and on the left a close up on the distal joint surface. ...