By Dr. Becker
A recent study of obese dogs with osteoarthritis and lameness proved how little effort it can take to vastly improve the quality of life of overfed, disabled pets.
The purpose of the study, conducted at the Small Animal Hospital at the University of Glasgow Veterinary School in Scotland, was to evaluate both subjectively and objectively the effect of weight loss on lameness.
The results of this elegantly simple 18 week study are fantastic.
Every parent of an overweight dog who suffers with arthritis and has difficulty walking, running, and being the physically active animal he was born to be, should be extremely excited by this news.
The study involved 14 family dogs including a Border Collie, a Bearded Collie, a Rottweiler, a Springer Spaniel, two Staffordshire Bull Terriers, two mixed breed dogs and six Labrador Retrievers.
The ages of the dogs ranged from 10 months to 13 years, with a mean of about 7 years.
The dogs were from 20 to 34 percent above ideal body weight, with an average of 24 percent.
Five dogs had bilateral hip dysplasia and secondary osteoarthritis (OA).
Two dogs had unilateral (single) hip dysplasia and secondary OA.
One of the two had a total hip replacement.
Only one dog of the 14 had a clearly identified cause of OA and hip dysplasia.
One dog had osteoarthritis in both hips and elbows; one had it in both elbows and one hip. Both these dogs had primarily forelimb lameness.
Seven dogs had the greatest degree of lameness in a forelimb and the other seven had a bigger problem with a hind limb. These were the limbs used to monitor progress in decreasing lameness during the study.
The dogs' body weight and pelvic circumference were measured at the beginning of the study, along with severity of lameness.
Lameness was evaluated using three different measures – a numeric rating scale (NRS), a visual analogue scale (VAS) (both of which are subjective measures), and a kinetic gait analysis (objective measure).
The dogs were placed on a weight loss program using commercially available food. Owners were instructed not to change the dogs' level of exercise for the duration of the study.
They were evaluated by the same person every 2 weeks for 12 weeks, then 4 weeks apart for the final 2 visits. Weight, pelvic circumference and severity of lameness at a walk and at a trot were measured at each visit.
Starting with visit 3, body weights were significantly decreased from starting weights.
Starting with visit 5, pelvic circumference was significantly reduced from starting measurements.
By the final visit, the dogs had lost on average 8.85 percent of their initial body weight. The pelvic circumference of the dogs was reduced on average almost 7 percent.
From visit 2 on, VAS lameness scores for both walking and trotting significantly improved week by week.
At visit 5, significant improvement in NRS lameness scores for trotting was seen.
At the end of the study, 82 percent of the dogs showed improvement in lameness.
The results indicate that when an overweight dog reaches about a 6 percent decrease in body weight, lameness is significantly decreased. Additional improvement is seen as additional weight is lost.
Kinetic gait analysis showed decreased lameness at a body weight reduction threshold of just under 9 percent.
So these results confirm that an obese dog with osteoarthritis can have noticeable improvement in lameness after losing just 6 to 9 percent of body weight.
Applying These Study Results at Home
Let's say the ideal average weight for a Labrador retriever is 70 pounds. And let's say your Lab weighs in at about 88 pounds, which is 25 percent over the ideal.
Chances are if your overweight dog doesn't already have some obvious arthritis and lameness, those issues are right around the corner. Bigger dogs, as we know, tend to have more joint and movement problems than the little guys.
Now let's say you put your dog on a portion-controlled, balanced, species-appropriate diet, with a weight loss goal of .5 to 1 percent of body weight per week. In as little as 6 to 7 weeks, with a weight reduction of between 5 and 6 pounds (about 6 percent of 88 pounds) over that period, you will have significantly reduced the stress on your dog's joints and improved his ability to walk, run and move around freely and comfortably.
Or ... let's say you have a sturdy Maltese whose ideal weight should be about 7 pounds. But your little guy is 30 percent heavier than he should be, tipping the scales at a little over 9 pounds. This is an obese Maltese.
Hard to believe a 9 pound dog is technically obese, but the smaller the animal, the quicker those ounces and pounds add up.
Using the .5 to 1 percent reduction in body weight per week goal, in 5 to 6 weeks your little munchkin will be a not quite svelte 8.5 pounds, and his little legs will have a much easier time helping him bounce around your house.
In another 6 weeks he'll be under 8 pounds, and you just keep up the good work until he's at his ideal weight and no longer at high risk for developing (or worsening) arthritis, lameness, and a host of other weight related health problems.
The commercially available food used in the University of Glasgow study was a 'prescription' diet dog food I absolutely do not recommend.
I also don't recommend non-prescription weight management or 'low fat' diets.
Your favorite canine should be fed balanced, species-appropriate nutrition, not the carb and fiber filled junk marketed as good for overweight dogs. In my experience those formulas aren't good for any dog, fat, lean or somewhere in between.
Portion control is another key element in helping your pet lose weight. For lots of information and suggestions on getting excess weight off your dog, view my 2-part video series:
Part 1 ... Why Heavy Dogs Are Becoming the Norm
Part 2 ... How to Help Your Chunky Dog Release Excess Pounds