Veterinary review of 2012

The year began, just as it is ending, with our attention focused on conditions caused by wet conditions underfoot, especially mud fever, thrush and white line disease. While recent weather has been dry, fields and paddocks simply haven't recovered from one the wettest summers on record. The result is conditions that are perfect for the bacteria and fungi that cause these ailments.

As I discussed back in January, eliminating infection with antimicrobial washes, scrubs and creams remains the cornerstone of treatment for mud fever, which may also require softening and removal of the scabs under which the causal bacterial hide away.

There are those, however, who suggest leaving mud fever scabs in place in the belief that they offer protection against further infection. I am not an advocate of this, especially when the infection is associated with lameness, soreness to touch or swelling of the lower limbs.

Occasionally we do see cases where the infection is no longer active and it is perfectly acceptable to leave these scabs in place. In these horses scabs are dry on their underneath and often growing out with hair.

Late in January I exchanged the dreary winter for the bright lights of Amsterdam and a conference on equine sports medicine that was being held in conjunction with an international dressage and jumping show.

My column in February reported of the topics discussed and specifically sacroiliac joint and proximal suspensory ligament injuries. Along with along with hock osteoarthritis, these continued to be most frequent orthopaedic causes of poor performance during 2012. Gastric ulceration and inflammatory respiratory disease proved once again to be the main medical conditions that affected athletic capability.

In March, attention turned to the upcoming breeding season. With economic pressures forcing studs to offer financially attractive packages, 2012 should have been a good year to breed. But this promise did not translate into activity and it was certainly a quiet breeding year, at least in our practice.

Many studs and breeders also reported that mares were more difficult to get in foal in 2012. Those that had previously conceived to artificial insemination at the first attempt were taking two or three cycles; an obvious culprit was the highly variable weather conditions of the summer.

The inheritance of horses' behaviour and temperament was the subject of April's article. This was prompted by someone asking whether we should be breeding better behaved horses for riding schools.

But research indicates that less than 10% of a horse's temperament is genetic in origin, and that only 30% of behavioural characteristics are inherited. Instead, the majority of a horse's personality is shaped by environmental factors, such as diet, workload and interaction with humans and other animals.

May's column dealt with the ever increasing problem of sarcoids. These benign skin tumours are caused by a virus –the one that causes warts in cattle - in genetically susceptible horses and donkeys.

Earlier studies indicate that sarcoids affect 7% of horses in the UK but many vets are of the opinion that they are now much more common. Their nuisance lies in the fact that they tend to recur following removal or treatment, either at the same site or other locations on the body.

In the past year we and many other vets have increasingly prescribed a cream for sarcoids called Xxterra, which contains an extract of the Bloodroot plant. This is applied for several days and has the advantage that owners can use it themselves, whereas the effective sarcoid cream from Liverpool University can only be applied by vets.

In June I reported on a new anti-inflammatory drug for horses called firocoxib. Marketed under the name Equioxx, this is available as an intravenous injection and palatable oral paste.

A key feature of firocoxib is that it is more selective in its effects, and thus has less potential for side effects such as gastric ulceration, than other anti-inflammatories. I have certainly found it useful in treating foals, who can be very sensitive to drugs like 'bute', and horses prone to stomach ulcers.

The columns in July and August focused on the Olympics, with the first one detailing the organisation of transport and stabling at the games. London 2012 was unlike previous games – notably Hong Kong in 2008 and Sydney in 2000 – in that nearly all of the horses travelled by road from bases within the UK, Ireland or Europe rather than arriving on long-haul flights.

This meant that disease risks posed by both exotic diseases, such as African horse sickness, and endemic diseases like strangles were lower than when horses are shipped from their country of origin just in time for the Games. Despite this, the health and welfare of horses at London 2012 was subject to intensive planning and nothing left to chance.

An outbreak of equine influenza in Normandy, France, just prior to the Games heightened alert. But the Games passed uneventfully, biosecurity procedures worked admirably and horses were moved in and out of Greenwich without hindrance or delay.

Veterinary matters at the Games were also the subject of the second article. The Greenwich venue provided a stunning backdrop for the equestrian and modern pentathlon events delivered everything that could have been asked in terms of facilities, competition and GB medal success.

The absence of a drugs scandal was in marked contrast to Beijing 2008 - where six horses failed doping tests - and contributed to greater public appreciation of equestrian sport. Perception of equine welfare also remained unblemished. Although there were several horse-falls on the cross country course, there were no serious orthopaedic injuries and only one animal required hospitalisation having suffered a punctured lung and suspected fractured ribs.

An anxiety going into the Games was the artificial surface for the main arena. Concerns were expressed following the test event in July 2011, when show jumpers described the surface as "pudding" and their dressage counterparts called it "dead". But these issues were overcome and the final surface rode perfectly, receiving wide acclaim from riders in all disciplines.

In September euthanasia and the difficult decision of when to say goodbye to horses was discussed. This was prompted by the fact that, as autumn arrived, owners were looking hard at whether to put older or less than healthy horses through another winter. Financial pressures from increasing feed prices and other costs of care were also a factor for some owners.

Disease threats from swamp fever (equine infectious anaemia) and equine influenza were the subjects of articles in October and November. Vets were placed on high alert following the finding of swamp fever in two horses in Cornwall in the autumn. Fortunately control measures stopped its spread and no further cases have been reported.

Equine influenza is a highly contagious disease and outbreaks were sporadically reported in the UK in 2012, including late in the year in Roxburghshire. Fortunately none of these were on the scale of that which devastated the equine industry in Eastern Australia in 2006 and part of the reason for this is the high prevalence of flu vaccination in the UK.

Despite this, there are concerns that some outbreaks, particularly those in horses that have been vaccinated, may be due to virus strains not covered by current vaccines. While pharmaceutical companies are working to address this issue, comfort gained be gained from evidence that vaccines in use now can offer some protection and highlight the importance of maintaining vaccinations up to-date.