Big Hearts for Endurance

There has recently been some research published by the Animal Health Trust in Newmarket, which I think is relevant to ridgebacks.

In race-horses there has always been an old sporting dictum that big-hearted horses are often winners, at least in the steeplechase. Researchers who have studied 400 horses with ultrasound scans have proved that winning horses really do have large hearts that give them an advantage. However, this only applies to endurance steeplechasers but not sprinters.

Larger hearts are able to better process oxygen in the muscles and it is perceived that they allow a greater volume of blood to be pumped with each heartbeat. It is possible that winning horses could develop large hearts because of intense training but if this were the case all horses with the same training regime would develop large hearts.

I thought this research interesting as, in my opinion, it enforces some of the points which are in the standard. It does not matter how large the heart is, or how efficient it is, if the animal does not have sufficient heart room. As our hounds are endurance hounds, (or were originally bred to be), this enforces that hollow-chested, herring gutted, narrow hounds are unacceptable.

The standard calls for the chest to be ‘deep and capacious’ with ‘ribs moderately well sprung’. When assessing the chest from the front a long rectangle should be formed by the inner space created by the forelegs and chest. If you look at the outer outline formed from the front. elbows can give a false impression; if pinned in the chest can look narrow or if the elbows are loose, the impression is that the chest is wide.

There should not a cathedral arch and just because many in the show-ring have this fault does not make it correct. The chest should be of sufficient width but not too wide. From the profile the chest in an adult dog should drop to the elbows and the depth should be roughly the same from the withers to the elbows as the measurement from the elbows to the ground.

Ribbing is also important as well-sprung ribs allow the lungs to oxygenate the blood more efficiently. As the dog draws in its breath each rib rotates upon its own axis so that it starts by facing in a backward direction and ends up by facing outwards and a little forward. If the ribs are not well sprung there will be little difference so far as chest expansion is concerned but when the ribs are well sprung, the change from the resting position to their full extension, will increase the diameter of the chest and therefore greatly increase the quantity of air which is sucked in. Barrel ribs and slab sided ribs are inefficient as they will not have the ability to expand and contract in this way.

So width and depth of chest are important but the hound should also be well ribbed back. That is that the ribs are well spaced because the thoratic vertebrae to which they are attached are long to give maximum space. This also allows protection for the organs.

Although not mentioned in the standard, the cut up should be moderate, too steep and maximum space is not allowed for the organs, too straight and it would impair the hounds ability to obtain a ‘fair amount of speed’ and the necessary agility.

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