Glucosamine and chondroitin are substances that naturally occur in the body of dogs. They are at their highest concentration in cartilage. Almost all of the glucosamine in your dog’s diet is unavailable for use due to degradation during digestion and processing, therefore, the body synthesizes most of its own glucosamine through a biochemical reaction utilizing glucose. In healthy dogs, the body is able to synthesize enough glucosamine to keep the existing cartilage healthy, but when the dog ages or there is damage to joint cartilage it cannot produce enough to keep up with the body's needs.

Types of canine arthritis

• Osteoarthritis
•  Degenerative Joint Disease
• Hip osteoarthritis - hip dysplasia
• Elbow osteoarthritis - elbow dysplasia
•  Knee osteoarthritis - knee dysplasia
•  Knee (stifle joint)
•  Osteochondrosis
• Hypertrophic arthritis
• Shoulder (degeneration)
• Wrist Arthritis
•  Kneecap (dislocation)

Glucosamine

Glucosamine is the primary component of nearly all arthritis formulas and seems to be the most important. It is essential for the formation of joint cartilage and synovial fluid. The three forms of glucosamine, N-Acetyl Glucosamine, Glucosamine Hydrochloride, and Glucosamine Sulfate are naturally occurring substrates used by the body for the biosynthesis of special macromolecules called glycoproteins, glycosaminoglycans (GAGs), and proteoglycans. Glucosamine’s are part of the structural elements in cell walls, intercellular spaces, and connective tissues and give shape, elasticity and rigidity to such tissues as cartilage, tendons, ligaments, intervertebral discs, and mucous membranes.

• Glucosamine Sulfate and Glucosamine Hydrochloride help glycosaminoglycans to hold more water thereby increasing joint flexibility, cushioning ability and resilience.
• N-Acetyl glucosamine is produced from Glucosamine in the body and supports proper functioning of the digestive tract lining. All three forms of Glucosamine are considered important nutritional factors.

Chondroitin

Chondroitin sulfate is an important structural component of cartilage, along with glucosamine, chondroitin sulfate has become a widely used dietary supplement for treatment of osteoarthritis.

Uses of glucosamine and chondroitin

Glucosamine is predominantly used for relief and healing of the symptoms of joint disease, it is also used for the healing of skin wounds, stomach ailments, and joint problems.

There are many different joints that can be affected by osteoarthritis in the dog, but by far, the most common is the hip joints, especially in the large breeds who often suffer from hip dysplasia. This condition greatly exacerbates the normal wear on the smooth cartilage protecting the bony surface of the joint. When this cartilage wears away there is a bone to bone contact, which creates the pain seen with arthritis. Aging dogs may also suffer from arthritis in their knees, elbows, and shoulders and cartilage loss or damage that can be improved with glucosamine and chondroitin supplements.

Glucosamine and chondroitin are also often used as an aid post operatively injury’s in dogs that have undergone joint surgery.

How do glucosamine and chondroitin work?

Glucosamine and chondroitin are two molecules that make up the type of cartilage found within joints. Inside your dog joints, cartilage undergoes a constant process of breakdown and repair. However, to be properly repaired, the building blocks of cartilage must be present and available. The theory behind using the glucosamine and chondroitin joint supplements is that more of the cartilage building blocks will be available for cartilage repair.  

• Glucosamine is a precursor to a molecule called a glycosaminoglycan, this molecule is used in the formation and repair of cartilage.
• Chondroitin is the most abundant glycosaminoglycan in cartilage and is responsible for the resiliency of cartilage.

Treatment with these joint supplements is based on the theory that oral consumption of glucosamine and chondroitin may increase the rate of formation of new cartilage by providing more of the necessary building blocks.

Supplementation with glucosamine and chondroitin 

 Supplementary glucosamine is obtained from chitin, an ingredient found in the shell of crustaceans. Crustacean shells have a very high concentration of chitin and because the shells are often discarded, this provides a reliable and cost effective source of glucosamine.

Supplemental chondroitin is derived primarily from bovine (cow) cartilage, particularly the cartilage rings of the trachea. It is also derived from shark and whale cartilage. The source does not appear to have any impact on its effect.

Once a dog begins using the product, they must stay on it for the rest of their lives or the degeneration of the joint cartilage will return. Once the product has promoted healing for 8 weeks, the dose is often reduced. The safety of this product is well suited for long term use. It can also be used with most other drugs and vitamins without any complication. The owner of any animal that is taking a medication should always seek veterinary advice before adding any new product or drug. Products such as Seraquin for Dogs with Glucosamine and Chondroiton, Cosequin Double Strength Capsules, and Cortaflex Canine/Feline are popular for the use in dogs.