Glucosamines increase the production of synovial fluid and also somewhat increase its viscosity, this is not only in horses, but also known in humans or dogs. This makes the joints better lubricated, so to speak. If the viscosity of the fluid in the joints is too low, the cartilage becomes harder and harder and wears out in a different way. Incidentally, articular cartilage is subject to a constant balancing process between degradation and reconstruction anyway. The following factors cause a pathological imbalance in this respect:
- Extreme loads
- The opposite, too little exercise, is also very harmful
- Severe bumps or bruises, also known as traumatic injuries
- Prolonged or chronic inflammation
- The aging process
At high running speeds or when jumping over high obstacles, the joints are subjected to particularly high stress with the result of particularly high abrasion or degradation of the cartilage layers that rub against each other, whereby many cartilage cells (chondrocytes) are destroyed. In the case of bruises or impacts, the cartilage mass can be compressed to such an extent that cracks can even form. In humans, this is how the frequent meniscus damage occurs. This disturbs the entire course of movement, and the horse naturally tries to relieve the affected joint at the expense of its other joints.
The next, usually inevitable step is then joint inflammation, in which increased joint fluid is produced, further increasing the pressure in the joint. Accelerated degradation of cartilage cells accompanies this. Then, as the animal gets a little older, the cartilage composition changes so that both its water content and its elasticity decrease.
Lack of exercise
The above-mentioned balance between cartilage degradation and reconstruction works like this: Every time the cartilage is (slightly) compressed, some fluid leaks out into the synovial fluid, and some cartilage cells are transported away with it. When the cartilage expands again, nutrient-rich fluid is then drawn in, so to speak, from which new cartilage cells are then formed. This constant process during the normal movement of the joints roughly illustrates what is meant when one speaks of "self-lubricating parts" in connection with the joints.
What contribution can nutrition make?
A horse with a high-quality and also balanced diet has basically very good chances for an excellent development of its musculature and also for a good skeletal development, which includes the entire cartilage mass. However, there are well effective preparations from glucosamine glycans, especially glucosamine sulfate, which can be fed in addition. They are usually obtained from the cartilage of shellfish.
Many owners of sport horses confirm the amazingly positive effect of these preparations, which, by the way, has already been proven in studies in dogs and also in humans.
In what cases is supplemental feeding of glucosamine sulfate indicated?
In principle, this can and should be done with all sport horses and those horses that are otherwise required to perform at a high level. It should also be remembered that cartilage has neither nerves nor blood vessels running through it, so there is no warning system that could indicate disorders in time. Like oh humans, horses feel pain only when the cartilage is already permanently destroyed, i.e. the bones rub against each other or even bone splinters block any movement. One may therefore assume that the horses are in severe pain when they do not want to move at all.
Many feed manufacturers have already reacted to this and offer vitamin and concentrated feed containing glucosamine. However, this usually does not have the desired effect, since the glucosamine content is usually too low and the vital substances are only artificially imitated anyway. Glucosamine sulfate can also be synthesized, but it has been clearly shown that only its biological variant can be properly absorbed by the body. "Green-lipped mussel extract," for example, contains little active ingredient and is sometimes contaminated with heavy metals or even toxins. Its gelatin does not contain what it promises and therefore also remains ineffective.
Glucosamine glycans and glucosamine in particular are not drugs, but natural food components. For horses that (have to) move a lot, adding these substances to the normal diet is definitely recommended. Negative side effects could not be confirmed in any case so far. Natural glucosamine is obtained from shellfish and chondroitin sulfate from shark cartilage.