Date: [__date__]

Dear [__name__],

Welcome to the first newsletter of Tweedie & Associates Equine Veterinary Services. We are excited to bring our clients the very latest in equine research news and are looking forward to keeping everyone up to date over the coming years.

Practice News

We were very excited to unveil our new website on the first of July. If you haven’t already seen it, please have a browse and familiarise yourself. We hope you find the information useful and the website easy to navigate. Please do not hesitate to contact the clinic if you have any suggestions for information sheets or future newsletter topics.

We are pleased to have Dr Lara Savva back after attending the International Society of Equine Locomotor Pathologists (ISELP) course on the Hind limb Metatarsus and Digit. Lara was fortunate enough to spend time at Fairfield Equine Associates in Connecticut, home of Dr Rick Mitchell, team veterinarian for the United States of America at the 2008 Olympic Games. Fairfield Equine Associates is recognized for excellence in the care and treatment of the sport horse and we are excited about the knowledge and experiences Lara has brought back to our practice from her trip to America.

Dr Mike Tweedie is off to America in August to attend the ISELP course on the Hock being held at Penninsula Equine Medical Centre in California. We look forward to benefiting from the knowledge and experiences Mike will bring back to the practice from his trip to America.

Influence of foot conformation on duration of competitive life in a Dutch Warmblood horse population.

Researchers in The Netherlands undertook an excellent study examining the databases of the Royal Dutch Warmblood Studbook Federation (KWPN) and the Royal Dutch Equestrian Sports Federation (KNHS). They examined the records of 23,116 horses for which conformation scores and duration of competitive life were available.

The researchers found that duration of competitive life was shorter for jumping than for dressage. They also found that uneven feet (club or boxy feet) shortened the competitive life of a dressage horse and significantly shortened the competitive life of a jumper. The researchers actually found that uneven feet almost doubled the risk of early retirement in elite jumpers.

Interestingly, height at withers was also a risk factor for early retirement in dressage and jumping horses. Even more interestingly, the influence of height at withers on early retirement was larger for dressage horses than jumpers. This seems contradictory, because larger horses are often preferred for dressage. However, high growth rate is often associated with lower limb quality (epiphysitis, osteochondrosis), so these fast growing horses may be more predisposed to diminished lower limb quality and it could have been on this basis that the horses in this study were retired early.

Interesting information and something to keep in mind when you are shopping for your next superstar!

Ducro, B. J., Gorissen, B, van Eldik, P. and Back, W. (2009) Influence of foot conformation on duration of competitive life in a Dutch Warmblood horse population. Equine vet. J. 41 (2) 144-148.

Injectable Joint Products Demystified

It has been our observation, that the plethora of joint products available for the performance horse is one of the biggest sources of confusion for owners, riders and trainers alike. In light of this, we would like to use this issue of our newsletter to provide our clients with information on the different products that are available, which combined with our advice, will help them tailor an informed and rational management program for their horse.
 

   Hyaluronic acid

Hyaluronic acid (HA) is a normal component of the articular cartilage and synovial (joint) fluid within the weight bearing joints of the horse.  A thin layer of HA covers articular cartilage and helps it resist compression and retain its elasticity. HA also provides lubricating properties to synovial fluid.

HA is often used in the treatment of joint disease in the horse. Our practice uses HA as an intravenous injection and in conjunction with corticosteroids as an intra-articular injection. It is our clinical impression that HA administration results in an appreciable reduction in lameness in suitable cases. Our clinical experience is supported by the results of research into the beneficial effects of HA in the management of joint disease in the horse.

It is well known that intra-articular injection of corticosteroids on their own contributes to joint cartilage breakdown in the long term. However, researchers have successfully demonstrated a protective effect of HA on articular cartilage after intra-articular injection in conjunction with corticosteroids. Other researchers have observed increased collagen formation in HA treated joints. In addition, HA is also believed to have an anti-inflammatory effect when administered intravenously.

It is important to realize that not all HA products are created equal. For example, the lower the protein concentration, the purer the HA product and the less chance of a ‘flare’ (heat and swelling) reaction after intra-articular administration. It is also thought that the use of higher molecular weight HA products result in longer intervals between treatments. Our clinic has carefully selected the HA products we offer our clients on the basis of protein concentration, viscosity and molecular weight and we are confident that the products we administer are the best available to the Australian market.

Please do not hesitate to contact one of our veterinarians to discuss how HA can be used in the management of your horse.

    Polysulfated glycosaminoglycan

Polysulfated glycosaminoglycan (PSGAG) is a semi-synthetic preparation from bovine trachea. It is mainly comprised of chondroitin sulfate which is a normal component of cartilage.

Adequan is the commercially available form of PSGAG. It is available in North America as both intravenous and intra-articular preparations. It has not been available in Australia for some time, however reports from the USA indicate that it will be returning to our domestic market in the foreseeable future.

PSGAG is thought to have anti-inflammatory effects and is also thought to inhibit the activity of a number of degradative enzymes present in the articular tissues of arthritic joints. Basically, this means that PSGAG is thought to have a cartilage sparing effect in arthritic joints.

   Pentosan polysulfate

Pentosan polysulfate is a preparation made from beechwood hemicellulose. The effects of pentosan polysulfate are similar to PSGAG. Pentosan polysulfate is thought to have an anti-inflammatory effect as well as inhibit degradative enzymes that damage cartilage in arthritic joints. In addition, it has also been suggested that pentosan polysulfate adminstration results in the upregulation of HA production.

There are three commercially available, intramuscular preparations of pentosan polysulfate sodium and two are registered for use in horses. Zydax is the newest formulation on the market. Zydax is manufactured by Parnell Laboratories Pty Ltd and is available in 6 ml vials in a concentration of 250mg/ml. Pentosan Equine is manufactured by Nature Vet Pty Ltd and is available in 6 ml vials in a concentration of 250mg/ml.  The third preparation of pentosan polysulfate sodium is called Cartrophen Vet and is licensed for use in small animals. Cartrophen Vet is manufactured by Biopharm Australia Pty Ltd and is available in 10ml vials in a concentration of 100mg/ml.

Please do not hesitate to contact one of our veterinarians to discuss how pentosan polysulfate can be used in the management of your horse.
 

Kind Regards

Tweedie & Associates Equine Veterinary Services