Obesity – Is my horse the correct weight?
What is obesity?
Before we can do anything about a problem, we have to be able to recognise a problem. Obesity is becoming an increasingly common discussion point and whereas historically, only malnutrition was considered as an abuse of the horse, we may not be far away from RSPCA officers pursuing prosecutions of Owners of Obese horses.
Body mass index is a controversial topic in human medicine, in horses we commonly use a body condition scoring system. Depending on the system used a score is ascribed to a horse, either between 1 and 5 or 1 and 10.
The features used to specify the obese scores are, ribs difficult to or impossible to feel, crease present along midline back, large crest and fat around tail head, fat in inner thigh, possibly causing rubbing together when walked, bulging fat over shoulder blades or rump, withers no longer prominent as covered with fat. In these scoring systems, 0/1 is thin and 5/10 is fat, (4-5 or 7-10 being obese).
How do we measure Equine Obesity?
Why is obesity a bad thing?
There are many reasons why obesity is a bad thing and surprise surprise, they are very similar to the reasons why being obese is bad for humans.
Obese animals are metabolically compromised by their obesity. Obese horses can suffer a peripheral Insulin resistance (which is not unlike Type II diabetes in humans) which is in effect a form of avoidable Cushing’s syndrome.
Obese horses are at a much greater risk of Laminitis, they are more likely to suffer from performance limiting arthritic joint disease, they are at greater risk of colic from strangulating lipoma, their reproductive function is more likely to be compromised and obese mares are far more likely to have problems foaling ( if they were able to conceive in the first place.) Having foals and youngsters overweight can be extremely detrimental also. Conditions such as OCD and most of the developmental orthopaedic diseases are much more likely in animals that have high calorie intake and reduced exercise potential (i.e. the ideal conditions for being overweight) any conformational defect is only going to be made worse if the limb concerned is having to support additional body weight, therefore, a combination of nutritional and physical effects mean that being overweight has a significantly detrimental effect on joint development. These effects may also not manifest themselves in early life but be a time-bomb for premature onset of other problems later in life.
How should you control a horse’s weight?
Feeding horses is as much art as it is science, feeding to condition is a good basic rule, if a horse is too fat, it needs less food ( this is not Rocket Science!). Roughage is most important therefore reducing hard feed and replacing with roughage (hay preferable to haylage if overweight) is the first step. All dietary changes should be made gradually. Fat woolly horses do not need both rugs and extra feeding in the winter. For good doers, rough ploughing out a paddock and rolling it, allowing only bits of grass to grow through can help reduce total intake and increase exercise as the horse has to cover more distance searching for its grass.
Much has been made in the equine press of horses in the show ring being in “Show Condition”. I strongly believe that horses that are grossly overweight in a performance related classes, such as potential sports horse, hunter, etc. should be marked down as severely as if they were lame. Until judges and exhibitors recognise the deleterious effects of obesity we will continue to compromise the future athletic potential of our performance horses. We, therefore, need to concentrate our educational efforts both towards individual horse owners and the equine industry as a whole.
Feed the individual horse, not the horse in the textbook. It is always going to be a balancing act, constantly assess the horse’s weight and body condition and make changes to the diet related to that and the levels of work, always remembering to make those changes gradually. Also remember the horse is designed to have a degree of fluctuation of its weight throughout the year and a little extra weight in the autumn and a little poorer in the spring is natural.
