| Barycentre |
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The mechanism of gait cannot be fully understood without the comprehension of the concept of barycentre. The barycentre is an imaginary point in which all gravitational forces are equal and convert towards, condensed in a "focus". The barycentre in the dog's body lays in a spot in which, if the whole body were be suspended, it would still remain in balance. In most dogs, in a static position, the barycentre could approximately be traced at the center of the body, near the heart, where a vertical line, which runs through the caudal edge of the sternum, intersects a horizontal line, passing throuh the sagittal plane of the body, at half chest height. If an imaginary quadrangle was drawn with its four corners corresponding to the dog's feet (prop basis), one could easily see that the perpendicular line from the barycentre to the ground (gravitational line) falls always, when static position is assumed, within the imaginary quadrangle. If the dog moves, the barycentre moves forwards so the gravitational line falls outside of the prop quadrangle, the animal won't be able to keep balance and therefore will have to move forward his front limbs, to avoid falling. Hindquarters will have to follow the forward motion and that will initiate movement. We can conclude that the wider the prop basis (feet transversaly far apart) the better the static balance (as the bulldog). The smaller the prop basis in comparison to the size (feet rather close to each other and short body, as the hounds) is more likely for the barycentre to fall out of the basis: the subject loses stability but gains in speed. It is worth stressing the dog's balance increases as the barycentre is closer to the ground, whereas it decreases the higher the barycentre. The Saint Bernard is a rather tall dog, therefore his barycentre is quite high above the ground; nevertheless the prop basis is rather wide and long, so his instability and therefore speed are conspicuous but moderate.
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| General considerations |
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We have had the opportunity to say on many previous occasions that before expressing a judgement on gait of any dog breed we should first get acquainted with that particular breed's body structure. Indeed, a particular kind of motion belongs to each body structure. It is axiomatic that, although general rules on all dog body structure exist, each breed has its specific and characteristic structure and peculiar gait. For example, a german shephered has a body structure and therefore a gait that differs greatly from that of an alano dog; a terranova has a body structure and therefore a gait that differs greatly from that of a boxer, and so on. It is a mistake to assume that the head itself represents sufficient type characteristic and that the rest could be overlooked. We agree that, when judging, extra attention should be paid to the head because a dog of fine body structure but with a bad head is worth nothing. But the judge has also the duty of assessing the typicalness of the body structure and hence gait. Among exemplars of the setter-family (English, Irish and Gordon) there are no similarities in body structure and therefore no similarities in gait. With this example we want to underline how structure and gait are peculiar for each breed and represent the "breed type". Let's consider now, to fully understand, which are the morphological characteristics of the Saint Bernard dog, that is if he is a galloper or a trotter, or if within him prevail galloper or trotter characteristics, since this dog is a heavy-weight of canine species, any assessment has to be based upon his size. It's like expecting a heavy weight boxer to move as a fly weight. In spite of this we should demand from the heavy-weight agility, tonicity, endurance. We believe a "Cassius Clay" in his golden era, swift, loose and of quick reflexes, is to be considered an excellent Saint Bernard dog. A Saint Bernard of excessive weight and short on limbs will never be able to perform any task. He will be a torpid being who will fall exhausted after 500 meters. The same goes for too small or too light Saint Bernards: the Saint Bernard is like a man 1,90m tall that weights 90kg and not like a man of 1,70m and 90kg, or 1,50m weighting 50kg. The description of a Saint Bernard like this is what you deduce from the standard and tradition. It is an embellished work-dog. In other words it is a dog who, if trained since he was a puppy can perform successfully, as his ancestors, hard mountain work-tasks, as has been described in the past: spot a buried person, if possible dig a tunnel through the snow to reach her, drag her out to a safe place, cover great distance on frozen snow without breaking the balls of his feet, all things that a German shephered for example could not perform. Today man himself carries out almost all rescue tasks, helped by sophisticated mechanical means, so that canine help is reduced to minimum and even employed dogs of not properly mountain breeds. Dog shows have the merit of introducing various breeds to a large audience. Among them many assets 110 have a fault: and that has induced many breeders in turnig their work-dogs into mere "exhibitional subjects". This occured in particular in England and in America. In England, for example, we can view English setters the size of a Terranova win the Bis or greyhounds, very fast dogs per excellence, perform a wonderful trot in the narrow space of a ring and for a few minutes, but entirely unable to gallop chasing game. The same could be said for other breeds. In America, where gait is highly considered and prevails when evaluating a dog (truly the judge has to evaluate in particular the animal in motion, after a quick assessment in the static position) the Saint Bernard suffered modifications aiming to a smoother motion on the ring. In other words, he has been transformed from an 80% galloper which he is by nature, into a trotter morphologicaly resembling a German shepherd who is, as we know, the best trotter among dogs. The German shepherd is well-known for his slant roundish croup, hindquarters of long very angulated bones, sloping shoulder and arm: he is all together very flexed in each part. Besides, during both walk and trot, he covers wide terrain, smoothly trots for hours, fluidly and without showing fatigue. When walking his back footmark outmarches the front one. His gravitational center is rather close to the ground so that the prop basis is exceptional. The relation between the length of his bones and his angles are in favour of this kind of motion. When evaluating a German shepherd, which is mainly an assessment of gait, one must ascertain that the relation between hindquarters drive and front quarters extension was established, the extension is gained by a perfect angle between the shoulder blade and the upper-arm (100°/105°/110°) which gives to the front quarters the strong drive from the back. The upper-arm in particular has to be longer and more inclined that in other breeds. Certainly many people noticed that when exhibiting a German shepherd in the ring, the conductor tends to lift his front, so the dog could tollerate the great drive from the back without falling forwards. In fact, in the German shepherd there is always an excess of back drive prevailing over their capability of covering front terrain because not many subjects have the upper-arm and shoulder blade at proper angulation. Only in rare cases balance is reached, and that is when we witness a potential auslese candidate. The mistake made by both Swiss and Americans was the adoption of the German shepherd as a model to study Saint Bernard's gait, as we just said, the German shepherd has a body structure, gait and general aptitude that differs greatly from the Saint Bernard's. Trying to emulate the morphology and gait of the German shepherd means a complete misrepresentation of the Saint Bernard breed. The Saint Bernard displays a hybrid form of galloper-trotter in which prevails though the galloper element, as we saw, of 80%. That means that the hindquarter's drive during Saint Bernard's walk or trot tends to be less of the front extension, unlike in the German shepherd. As the standard correctly states, hindquarters in the Saint Bernard are moderately angulated whereas his front forms a rather tight angle because of the shoulder blade and upper-arm of considerable length. This fact allows a greater extension of the front in comparison to the drive given by the back. To be more precise we could say that the Saint Bernard could in theory, during walk and trot, cover more terrain with his front than with his back. Indeed, within this breed the hind foot covers but never overmarches the front footmark, as with the German shepherd. What did the Americans do to improve gait on the ring and extend Saint Bernards' lope? What did they do so that the footmark of the hind would overmarch the front and the whole locomotory system would become more efficient? They reduced size, extended not only the dog's body but, in proportion, the hind bone segments too, strongly increasing its angles shifting the croup inclination from horizontal to slant. This way the impulse (that originates in the hocks and passes through the head of the femur and the acetabulum towards the spine and runs through to the front chest region) finds no obstacles and the motions turns from rigid to fluid and smooth. In other words the impulse runs through a more harmonic curve with following a trajectory closer to horizontal that the work-type Saint Bernard's which has a greater up-drive. These changes made American Saint Bernard's walk and trot nicer but turned a mountain dog into a dog suitable for the plain or, better yet, for the ring exclusively. So if we were to modify the hindquarters of a Saint Bernard increasing the angles and hence posterior limbs bone length (femur, tibia, metatarsus), turning the croup from horizontal to slope, we would enhance trot performance but alter utterly the typical mountain dog body structure required by the standard. The moderate hind angle in mountain dogs is the answer to a precise need: motion and lope uphill, because the rather wide tibio-metatarsal angle (always associated with a horizontal croup) allows less effort on cliffy terrain. In mountain dogs, thanks to their back angle span, hind extension and contraction is greater, where ischio-tibial muscles are longer and therefore more contractable. We have to add that in the work-type Saint Bernard thighs are long which helps the limb's pendular sway. All mountain dogs have a similar hind: the Pyrenean, the Maremma-Abruzzese sheepdog, the Šarplaninac, the Caucasian sheepdog, the Spanish mastiff, the Pyrenean mastiff, and so on. That is of fundamental importance to understand body structure and therefore gait in our Saint Bernard. provide a few sketches illustrating the path of the drive-line from the foot to the neck in the European and in the American Saint Bernard. Let's move on to the practical part. The complete empiric study of canine gait implies the exam of three kinds of motion: 1°) walk; 2°) trot; 3°) gallop. During shows, we judges leave out gallop assesment because, for the speed of strides, it can't be followed by the human eye. Gallop evaluation can be carried out through the exam of picture frames taken in fast succession or better yet shooting played in slow motion. On the other hand walk and trot, so different from breed to breed, can clearly indicate if the dog is more of a trotter or more of a galloper. We adopted the expression "more of" because exclusive form (dogs who are exclusive gallopers or exclusive trotters) are very rare indeed.
Only three of those come to mind: the German shepherd (very fast pure trotter), the greyhound (very fast pure galloper), the pointer (galloper of extreme endurance). The first two who could, morphologically, drive to limits their gait, have a back-line somewhat convex from a lateral prospective, while the pointer (who embodies a more natural shape of dog) has a straight back-line. Different back-line profiles correspond to the need of a better transmission of the drive-impulse from the hocks to the front accordingly to the respective gaits. Almost all dogs represent instead combined types, in which one or the other characteristic prevails. It doesn't mean that a German shepherd (pure trotter) couldn't gallop (even if with greater energy expense) or that a greyhound (pure galloper) couldn't trot (even if with greater energy expense). To the pointer (galloper of extreme endurance), trot is a suitable kind of gait. Considering the body proportions of the Saint Bernard, we can see he is closer to the latter not only one as far as the convergency between superior longitudinal axis of muzzle and skull (which qualify the way the head is held and therefore the whole body carriage in motion, meaning gait) but also for the straight back-line. During shows, the judge has to evaluate the dog on walk first and then on trot, observing him from the back, side and front during the two kind of gaits. Usually this is carried out by making the conductor cover an imaginary triangle which apex is the judge himself. If the judge prefers a different system he could move to a corner of the ring and make the dog circle along the sides of the ring. We personally prefer, when judging the single exemplar, the triangle, and for the play-off the other system, when dogs circle anticlockwise along the ring sides. In both cases the dog has to move on the inside and be visible to the judge. Obviously dogs of large size require a wider ring. Some judges never observe the subjects from the side and that is a fault, because the lateral prospective is the one that offers best information on a Saint Bernard in motion. It's worth stressing that examination from the side is more difficult than the front or back. It is not about analyzing details but to view and feel a functional balance of motion. We suggest that gait is correct when it corresponds to functional and aesthetic preconditions required by the breed. In other words when: 1. rhythm is regular 2. during walk and trot limbs move parallel to the median plain of the body 3. movements are firm 4. articulations take fully part of motion 5. vertical and lateral oscillation of the body are contained Top
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| Walk |
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It is a slow, natural kind of gait that suits the dog, it is marched in four diagonal strides: if the animal starts by moving the front right foot, the back left will follow, then the front left and lastly the back right foot. While perfoming walk oscillations are slight both lateral and vertical with a contained shift of the barycentre. Walk can be distinguished as: ordinary, shortened, elongated and detached. 1) Ordinary. Hind footmarks overlap the front ones (the animal covers himself). 2) Shortened. Hind footmarks do not overlap the front ones (the animal does not cover himself). Terriers have a shortened walk. 3) Elongated. Hind footmarks outrange the front ones (the animal outranges himself). The German shepherd has an elongated walk. 4) Detached. It is an intermediate gait between walk and small trot, a detached trot during which the period of suspension is suppressed. Strides are the same of the ordinary walk but much closer. The barycentre slightly shifts and gait is grazing. In walk the Saint Bernard displays already some of his peculiarities, such as: a) an alltogether compactness b) smooth movements c) balancing of the body mass d) synchronic relation between the hind and the front part e) drive and front extension f) wideness of footfall g) nobility of gait a) The alltogether compactness: means that the spine is very solid and presents no interruptions, convexities or concavities. When walking the back line should remain steady and straight as a board and must not suffer any kind of displacement. If the pelvis oscillates transversally that means the rachides, especially in the lumbar area (7 vertebrae) and in the last 2 dorsal vertebrae (12th and 13th) is weak. In the Saint Bernard the body is quite long as it exceeds of 10-15% height at withers, but the loin, "a suspended bridge" which joins the back to the front, must be short, besides being convex and wide, in other words very strong and solid. If it is long it determines excessive flexibility of the lumbar area (tottering loin) with an exaggerated transversal shifting of the croup (the so-called "anserine motion", which represents a severe fault). Nevertheless a strong oscillation could mean a strong transversal component (lateral displacement) is present within the propulsion force, because limbs are too short and and diameters too wide in relation to the height. These are serious faults and must be penalized. Articulations, even if manage to perform necessary motion, must not allow oscillation of bone segments which join. For example, it is easy to spot oscillating or wide-apart elbows and especially tottering hocks derived from faulty aplomb. They must be penalized as well.
b) The smoothness of motion: when the shoulder blade, the upper-arm, the metacarpus, the loin, the thigh and the leg posses the proper inclinations for the Saint Bernard and therefore a synchrony in the wideness and tightness of the different angles exists, gait becomes harmonious. Instead, when the wideness or tightness of angles is but partial, because of defects in length and inclination of the different bone segments, gait is rigid, unbalanced and cumbersome.
Sometimes, due to an inflammation of the hock articulation, the dog triggers and raises the hind limb putting it under the abdomen at every step he takes and then abruptly striking the ground with it. It is a defect we noticed in the Saint Bernard called "arpeggio". It must be penalized. Two other common defects of the breed, which must be penalized, are cold shoulders (when starting motion the backlash of the shoulders is scanty) and bolt shoulders (when the difficulty of moving the shoulder is permanent and does not improve with motion); this is an extremely serious defect..
Another important thing to observe carefully is the neck position during motion: if the neck is held low compared to the withers it means the dog has a weak hind, it is shifted to the front, the anterior part is overweighted and the neck is heavy. c) Balancing of the body mass: it expresses when there is a balanced relation between hind and front as well as balance among parts, due to proper angulations in the limbs and to well developed musculature distributed in all regions. d) Synchronic relation between the hind and the front part. In the Saint Bernard dog the walk is "ordinary", which means that the posterior segments are moderately angulated and the tibial-metatarsal angle is 145/150º (120º in the German shepherd, 150º in the Maremma-abruzzese sheepdog, the collie as well as in the Pyreanean mountain dog, 140º in the boxer and 128º in the pointer) so that the hind foot covers but never overmarches the front footmark. e) Drive and front extension. As we said, in the Saint Bernard hind lope is less than the ability of front extension, as in all mountain dogs. But they have a very strong front drive which helps the hind: this fact is due to these dogs are built for climbing. The propulsive drive of the front in the Saint Bernard is particularly intense and can be traced both during walk and trot. That is why a Saint Bernard is required to have a strong and properly angulated front. f) Wideness of footfall. As the footfall in the Saint Bernard is regular, it is put in relation to the height at wither at 75%. Shortened footfall is a severe defect and is shown as a consequence of an excessively horizontal croup (below 15º) with a straight hind or worse, with an oversagged croup (over 45º) with a straight on hind (dog sitting on his hind). This is a very common defect in Saint Bernards as in all dogs of large size and has to be fought. Another defect is an over-angulated hind which gives the dog a regular or extended footfall, but also a slow-down to its propulsory drive uphill and is therefore an expression of a scarcely efficient locomotory system. Another problem could be a straight shoulder which, when hind is proper, restrains the propulsive back-drive. In these conditions the dog is not able to successfully perform any task. g) Nobility of gait. It is erroneous to believe the nobility of a dog lies in the appearance of his head. Nobility transpires from each cell of the animal therefore from his figure and gait as well as from his temperament. A female needs to be elegant and balanced, feminine and distinguished, a male needs to be imposing, proud when walking and with stud characteristics. Nobility of gait in the Saint Bernard shows in the attitude- the neck is held slightly high when walking. Dogs who tend to hold their head at shoulder level or below, as we mentioned before, show lack of temperament, are stolid, lack in elegance and lose that majesty and nobleness the breed requires. During footfall limbs move parallel to the median axis of the body, that means perpendicular to the ground, as a train on rails. Hocks are still. If they should totter for the transversal oscillation due to aplomb defects, they should be seriously penalized. The tottery hock defect is better spotted on footfall than on trot, as we said earlier. Another defect that can be spotted from a posterior prospective is cow-hocks (the dog tends to hold his hocks tight together), the toed-in dog (the dog tends to hold his hocks far apart). Another defect is a faulty position of the limbs, not held parallel to the median plin of the body, a dog of wide or narrow hind (not to be confused with single tracking which expresses during trot). A frequent defect in a large number of breeds, both from a frontal and a posterior prospective, is a dog who crosses his legs while walking, that meanns the foot raises and makes a half a circle around the foot of the same pair which is backing on the ground, both front and hind. Other defects are tight together elbows or elbow valgus which compromise the whole motion of the front for the mancinism or toed-in situation they induce. Swaying gait: limbs don't move on the same plain: a) hind limbs are on the footmark, front limbs move outside the body-line. b) front limbs are on the footmark, hind limbs move outside the body-line. | |||||||||||||
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