Pet Obesity

Part 1

Today, we are exposed to the problem of human obesity on a daily basis. It is almost impossible to turn on the television, radio or open a newspaper or magazine without being inundated with some new weight loss supplement or diet plan. There is a good reason for this, since obesity has now become the leading public health crisis in the United States and is currently growing at an alarming rate.

Our pets are also suffering the same consequences of our own poor nutritional habits. The reasons for these are unlimited, but just as the media is supported through billions of dollars of advertising for healthy lifestyles and proper weight management, it also feeds on the snack and fast food industry's investment to get us to purchase more and more of that which is causing the problem; and as our pets have been given the "family member" status, this same type of advertising is now becoming rampant with the pet food and treat industry, pushing us to purchase highly palatable, fat laden treats for our special friends. In fact, nearly half of our pets are now classified as overweight or obese by leading veterinary healthcare providers, although most pet owners don't recognize it. This is a very serious problem that must be addressed if we hope to maintain our pets' health and enjoy their companionship well into their senior years. It has been noted with scientific studies that if you keep your pets thin, they'll live 15 percent longer; that averages to two years with the larger dog breeds and much longer with small dog breeds and cats. In addition, studies have proven what we already know, that normal weight pets suffer fewer health issues. By keeping our pets' weight controlled, many serious medical conditions such as diabetes; heart disease; hypertension; orthopedic problems including hip dysplasia, torn ligaments and related osteoarthritis; liver and kidney disease; and even cancer can be prevented. So simply stated, the worst condition caused by obesity is a greatly reduced life-span and unnecessary suffering.

To bring some important attention to this problem, I will be writing a multipart series. Some of the topics will include: causes of obesity, health risks associated with it, how to tell if your pet is obese, steps to get them back into shape, and information on an exciting new drug, Slentrol, that is the first safe and effective weight-loss medication made specifically for obese dogs.

Unfortunately, because of the unique nature of the cat's internal chemistry, this medication cannot be given to them. There is, however, ongoing research in search of a similar weight control medication for them and we hope that one will be available in the near future.

Part 2

Is your pet fat - or just large-boned?

What shape do you honestly think your dog is in? Unfortunately, for many of us, our impression rarely equates reality. In this article, I hope to teach you how to determine your pets' body condition scores (BCS) in a relatively objective way. Once you master the basics of a simple 5 point system and check all of your pets' scores on a regular basis, you can easily advance to a 9 point scoring system to fine tune their body weight. Which ever system you decide to use, 1/5 or 1/9 correlates with an extremely underweight condition and 5/5 or 9/9 is correlated with obesity. The perfect "ten" would then be a midpoint, either 3/5 or 4 - 5/9. I have a tendency of breaking down the 9 point system into halves so my ideal BCS for pets equals 4.5/9. And just as most of us would offer up an occasional "eleven" or "twelve" for that special girl or guy, I will sometimes find an extremely obese pet that tops the 9/9 score.

The criteria used for the standard 5 point body condition score system was initially developed for dogs and cats, but can be relatively easily adapted to almost any animal species. The easiest way to learn it is by using the following guidelines for Ideal Weight (3/5), Overweight (4/5) and Obese (5/5). Of course, the pet may also be Underweight (2/5) or Emaciated (1/5), but that's a topic for another article. So take a few minutes and study the diagrams and descriptions for each BCS and start scoring your own pets. Their overall health and longevity is dependant on you taking charge and keeping their weight under control.

Underfed Dog
Ribs are highly visible. Increase the amount you are feeding. After 2 or 3 weeks, compare again. Adjust until dog exhibits ideal body condition. Feeding to ideal body condition provides real, long-term health benefits, and the chart below should be used to monitor your dog's body condition. Since every dog is different, modify your feeding amounts as needed to help your dog reach ideal body condition.

The Body Condition System was developed and tested at the Purina Pet Care Center, and has been documented in the following publications: Laflamme, DP. Body Condition Scoring and Weight Maintenance. Proc N Am Vet Conf Jan 16-21, 1993, Orlando FL, pp 290-291. Laflamme DP, Kealy RD, Schmidt DA. Estimation of Body Fat by Body Condition Score. J Vet Int Med 1994; 8:154. Laflamme DP, Kuhlman G, Lawler DF, Kealy RD, Schmidt DA. Obesity Management in Dogs. J Vet Clin Nutr 1994; 1:59-65.

Overfed Dog
Dog has no waist when viewed from above. Belly is rounded when viewed from the side. Decrease amount you are feeding. After 2 or 3 weeks, compare again. Adjust as necessary.

Ideal Body Condition
Can feel and see outline of ribs. Dog has a waist when viewed from above. Belly is tucked up when viewed from the side. Maintain current feeding regimen.

• Promotes a leaner, longer, healthier life
• Reduces potential for developing weight-related health conditions
• Reduces a dog's percentage of body fat for better health
• Helps maintain healthy blood sugar levels
• Helps maintain healthy blood pressure and heart rate

Part 3

Most of us would equate obesity with overeating, but this is only partially true. In reality, it is an imbalance of too much food with too little exercise, or when the amount of calories consumed exceeds those that are expended over a lengthy period of time, commonly known by nutritionists as "a positive energy balance". A good example of this is the Olympic swimmer and gold-medalist, Michael Phelps, who during his heavy training consumes roughly 5 - 6 times or more calories than the average adult, yet remains extremely lean. However, if he continued to eat this much without his rigorous training, he would eventually become morbidly obese. On the other hand, when weight loss is our goal, a negative energy balance is required. If Phelps didn't consume such a large amount of food during his training season, his body would eventually waste away to the point of emaciation.

Regarding our pets, whether they are lapdogs who enjoy an occasional walk, house cats who prefer to lay in the sun, or canine athletes competing at a high level, a balance between the amount of energy (calories) consumed and energy expended or burned is critical to maintain a normal BCS (body condition score) and good health. When we encounter weight problems with our pets, the positive energy balance created as a result of their overeating or lack of exercise can usually be blamed on us, their owners. Most often, it is a result of feeding them free-choice or by not measuring the amount of food placed in the bowl, allowing the pet to eat from other pets' food bowls, feeding calorie dense foods to sedentary pets, feeding table scraps, or giving too many treats. Inadequate exercise becomes a greater factor with our indoor or kenneled pets, our already overweight pets, or our older, injured and/or arthritic pets.

Beyond these two primary factors, obesity can also be affected by several other risk factors, some of which are beyond our control. These include: hormonal imbalances such as Hypothyroidism; genetic predispositions of certain breeds known to have body weight issues (Cocker Spaniel, Dachshund, Sheltie, Terrier, Beagle, Basset Hound and Labrador and Golden Retriever); whether the pet is neutered or spayed can also impact weight control, similar to the middle age or older pet, as these pets have a slightly decreased metabolism and therefore will require less food intake; and finally, behavioral related problems usually created by owners that are constantly conditioning the pet into thinking that food or treats equals "love". Unfortunately, this is one of the most common causes of chronic obesity and the most difficult to control; because overtime, it becomes extremely difficult to break them of the constant begging or "sad eyes" look that results. Except for Hypothyroidism, these other factors can be easily controlled simply by feeding an appropriate amount of food and gradually increasing their exercise. Hypothyroidism can easily be overlooked in otherwise normal appearing patients. However, when diagnosed with a blood test, it can be easily corrected with an appropriate replacement hormone therapy; and once controlled, these pets will also respond to a properly managed weight loss program.

In the next article, I will discuss the four most common excuses veterinarians hear from the owners of overweight pets.

Part 4

As a veterinarian, my responsibility in practice, whether in the exam room, the medical ward or the O.R. is to be an advocate for my patients. And too often it can be a bit frustrating having to deal with owners of overweight or obese pets. I know that it may be hard to believe, but I really do not enjoy having these conversations, sometimes numerous times with the same owner regarding their pet's weight problem. So why do I take the time to have these discussions - because I care.

If you take this subject seriously and help your pet maintain a normal BCS (Body Condition Score), your pet can enjoy a longer life, suffering fewer health issues, thereby decreasing your pet health related expenses. In this article I will be sharing four of the most common excuses that pet owners respond with when we (veterinarians) discuss our concern over their pet's weight. Do you recognize any?

1. "I can't understand how she could be overweight, she hardly eats a thing." This is undoubtedly the most frequently heard comment. If the owner would just take a moment and think about what they are saying, they would see the fallacy in their statement, because whatever their pet is eating, it is obviously too much. In the majority of cases the pet has food available all day and nibbles a little at a time. By dinner time, the pet no longer has an appetite, so the owner starts to add "extras" such as high fat, calorie dense table food which not only creates the obesity problem, but also creates other problems noted below.
2. "What am I to do, he won't quit whimpering (or meowing) and giving me those sad eyes until I give him his treats." Over time the pet discovers that the more of a fuss it makes the more likely the owner will to reward them for their negative behavior. The owner out of frustration succumbs to the pet's demands and offers some food or treats to keep it quiet. In a short time this obviously "snowballs" to become a serious problem.
3. "But he's such a good pet and loves to eat - we don't want him to go hungry." In this situation, the owner equates love with food or treats, and when there are multiple family members that all secretly do the same thing; the pet is the one that suffers in the long run. We all experience a certain satisfaction with seeing our pets have a good appetite and enjoy a meal, but we need to balance this out with proper attention to other things such as grooming, dental care and exercise.
4. "I don't know what else we can do - she absolutely refuses to eat her own food." This pet has unfortunately been allowed to choose what it wants to eat and usually ends up eating high fat, poorly nutritious foods, the same things that children would pick if given the chance. This pet overeats not only because of the improper balance of nutrition, but because the endless variety of table food tastes so good, there is an immediate reward in eating.

We must face the fact that our pet's health and well-being depends on us; after all, we choose what, when and how much they eat.

Part 5

In Part I, some of the problems associated with obesity were introduced. This article will focus in greater detail on two of these complications. If we are overweight, we probably hear about weight related problems all of the time, either from our doctor, family and friends and/or television shows such as Oprah or The Biggest Loser. Our pets are prone to develop many of the same problems. Excessive weight endangers the heart and cardiovascular system, the lungs and joints; but other ailments such as diabetes, liver and kidney disease, skin and hair coat problems and even cancer can result from chronic obesity. In fact, every organ in the body is adversely affected by this condition, leading to the realization that obesity is truly a primary medical condition, which usually results in the degenerative secondary conditions already mentioned. This concept originated with the discovery of the hormone Leptin in 1994, considered by most researchers to be the most important breakthrough in the study of obesity. Since that time, new discoveries are continually being made, uncovering the complex factors that contribute to this serious disease. Today, the study of obesity is second only to cancer in research funding by the National Institute of Health.

Two of the most visible problems related to obesity in the dog is osteoarthritis and impaired respiratory function, and unfortunately, many pet owners do not associate these with their pet's weight problem, because obesity is an insidious condition that develops over time. It is now universally accepted that there is a direct correlation between chronic obesity and the development of osteoarthritis in weight and nonweight bearing joints, due primarily to the release of certain inflammatory chemicals by the fat cells of these patients, disrupting the normal balance of joint fluid, cartilage and bone within the joint. The stress of excessive weight on the joints is also a contributing factor, although not as important until the patient becomes morbidly obese.

Normal respiratory function is very often affected by chronic obesity, ranging from exercise intolerance to life-threatening medical emergencies such as collapsing trachea and heat stroke. These problems are associated more with the degree of excessive weight than with chemical production, as clinical studies have shown a significant decrease in lung expansion and dangerously increased efforts required during breathing.

If we can reduce or even eliminate these or any other consequences of obesity in our pets by simply helping them maintain a proper BCS (Body Condition Score), the fight against pet obesity is a battle worth winning.

In the next article, I will discuss the fat cell, and how it can evolve from being the storage organ for fatty acids and energy to a dangerous metabolically active secretory tissue.

Part 6

Fat, also known as adipose tissue, was once only thought of as a storage organ or "depot" for energy. In animals, it occurs in two forms, brown or white fat. Brown adipose is found mainly in hibernating animals and neonates. It has a good blood supply, helps to regulate body temperature and is an important aid in the metabolism of energy. White adipose tissue is the less vascular, most common form and easily and readily accumulates in overweight and obese animals. It has a necessary function in the storage and release of important fatty acids, but it also has the ability of becoming the greatest risk to our overweight pets' good health. This is also true with us, as we and/or our pets gain too much weight, the white adipose tissue quickly begins to accumulate in the abdominal cavity, and as we will soon learn, becomes a secretory organ, producing a number of very dangerous chemicals. In this article, I will discuss, without getting into too much science, how this happens. There is a tremendous amount of information that can be reviewed if you become so inclined, with new information coming to light every day.

The primary white fat cell, also know as the adipocyte, can begin to develop the ability to produce and release surprisingly high levels of more than twenty-one known chemical mediators, once a certain level of obesity is reached. This level can vary from individual to individual, and is not yet fully understood. Similarly, there is also a point at which the fat cells are triggered to multiply, creating an even greater threat to wellness. It is now well accepted that excessive white fat can become as metabolically active as the brain, thyroid, adrenal glands and pancreas, producing hormones that create insulin resistance leading to diabetes; the resistance of another important hormone called leptin, leading to an increased appetite and depressed metabolism; and other chemicals known as proinflammatory cytokines that can damage many body parts, including the joints, heart, blood vessels and lungs. The affects of these chemicals eventually leads to a diminished quality of life and premature aging. Once these fat cells divide, they become a permanent addition to the body. The only way to reduce the chemical production by these toxic metabolic factories in the body is to shrink their size with gradual and steady weight loss.

The take home message that I hope you will receive from this article is that prevention of obesity is much easier than trying to lose weight once we, or our pets, are already obese, due the hormone changes that occur, affecting appetite and energy metabolism. In light of all of this information, obesity is now recognized as an extremely serious disease that deserves the same urgency that clinicians have for other dangerous medical conditions.

In the next article, I will focus on three relatively easy steps that you can do at home to help your pet lose weight.

Part 7

The one question that I'm always happy to hear from a concerned owner of an overweight pet is, "How can I help my dog lose the weight?" In this article, we will look at three simple steps to take when trying to achieve this task, or as I would prefer to call it - responsibility. As I have repeatedly mentioned, the health and quality of life that our pet enjoys is a direct result of our efforts as their owner.

The most important thing that we can do is to practice some "tough love" with our best friend. This means measuring precisely the amount of the proper food, usually a commercial diet, that your pet is receiving every morning and evening. This is to ensure that your pet is receiving the necessary nutrients at the correct levels to protect their health during the weight loss period. It also requires that we keep treats to an absolute minimum. This can be a challenge when your pet is sitting by your side begging with those big, sad eyes. And be sure to inform your family, friends and neighbors so they aren't compromising your efforts by giving extra snacks to your pet.

Secondly, we need to increase exercise gradually as your pet gets into better shape. Start out with easy-paced five minute walk during the cool part of the day. As your pet's endurance increases, so should the length of the walks. Just as with dieting, this is common sense, but difficult to follow through with until you get back into a habit. If your pet is older, has an illness or injury, or is extremely overweight, check with your veterinarian on how to best introduce an exercise program with your pet.

And the third part of the process is open communication with your veterinarian. It is very important to keep them in the loop so that you can utilize their knowledge and experiences should you encounter a problem with your pet's weight loss program. They will be able to answer questions such:

a) What is my pet's ideal weight and how fast can I safely reduce the extra pounds?

b) What food, how much and how often should I feed?

c) When and how do I begin an exercise program - and how fast can I increase it?

d) Should I give any treats and what type would be best?

These three steps will require commitment on our part, but as my dad used to always tell me, anything really worthwhile may take some time and energy, but the satisfaction achieved with reaching our goals will more than make up for our effort. This is especially true with our pet's weight loss. Our reward is having them enjoy more happy and healthy years with us.

Part 8

The Pfizer Animal Health Company developed the following quiz to be used by dog owners to help evaluate their current feeding and exercise habits. Please take a few minutes and answer the following questions. You may want to share your answers with your veterinarian to help determine if your dog is at risk for obesity. (Unfortunately, a specific questionnaire for cat owners is not yet available. As soon as I find or develop one, you'll be reading about it in a future article.) Pfizer named it the BARC quiz, an acronym for Body Assessment Rating for Canines.

1. Is your dog a breed that is prone to obesity, such as retrievers (Labrador and golden), beagles, basset hounds, cocker spaniels, dachshunds, shelties, and terriers?
2. Do you have a multi-dog household? (Dogs in multi-dog households tend to eat more and faster than dogs in one-dog households.)
3. Is your dog over 5 years old AND still being fed the same type and amount of food as when he or she was younger?
4. Feel your dog's ribs. Do you find it difficult to determine where one rib ends and one begins?
5. Stand at your dog's side and look at the tuck-up - the belly area between the rib cage and hindquarters. Is the body more "square-shaped" in this area?
6. Do you regularly feed your dog table scraps and/or multiple non-meal treats each day?
7. When you feed your dog, do you just pour the food into the bowl (rather than giving a specific measured amount each time)?
8. Does your dog have difficulty standing up or jumping on the couch?
9. Does your dog get less than 20 to 30 minutes per day of outside exercise/play time?

Total the number of times you answered "yes":

1 - 3: There is a low risk that your dog is overweight or obese. You may want to repeat this survey every few months, especially if you see changes in your dog's weight.

4 - 6: Your dog may be overweight or living a lifestyle that could lead him or her to become overweight or obese. You may want to discuss your dog's weight at your next visit.

7 - 9: Your dog is at a very high risk for being overweight or obese. See a veterinarian immediately to discuss an action plan for your dog.

Part 9

Slentrol

Pfizer Animal Health, the division of the Pfizer Pharmaceutical Company, recently launched SLENTROL, an exciting new weight loss medication for dogs. After years of research and extensive testing in the US and Europe, final approval as a prescription medication was received from the FDA. It is formulated in an easily administered, once-a-day liquid that can be given directly by mouth or on a treat. Through surveys and other independent studies, Pfizer estimates that as many as four million American dogs are obese and potential candidates for this therapy. Pfizer is quick to point out that this is not a passport to abandon exercise or diets, but rather an important aid for owners who have a hard time cutting back on doggy treats. Slentrol is in a class of its own in the way that it works to reduce the appetite, hence the constant begging that results in our overindulgence with treats. Unlike human weight loss drugs that prevent fat absorption by the intestinal lining cells, (for example - Alli) resulting with certain undesirable side effects such as oily discharges, cramping and excess gas, Slentrol works in the small intestines of the dogs and through the release of certain hormones, stimulates the appetite center of the brain to feel full or satisfied. Without getting too scientific, I'll spend the remainder of this article on how this works.

As the dog consumes his meal, the fat (triglyceride) must be broken down into individual fatty acids and monoglycerides by a pancreatic enzyme (lipase) that is released into the small intestine, before the fat can be absorbed by the body. This absorption occurs in the cells lining the inside of the intestinal wall, known as enterocytes. Once inside the enterocyte, these digested fats are then "repackaged" with proteins to a form compounds (chylomicrons) that are then absorbed into the bloodstream and utilized by the body. When an excess amount of fat is absorbed, these chylomicrons are laid down as fat depots. (Refer to Pet Obesity - Part III) With Slentrol, this "repackaging" into chylomicrons is inhibited once inside the enterocyte, thereby preventing the absorption of the consumed fat by the body. As a result, these digested fats accumulate within the enterocytes, triggering the release of certain hormones (PYY) that enter the circulation, reach the hypothalamus (the appetite center of the brain) and acts as a satiety signal. This results in a decreased appetite to a level that is necessary to support a normal body weight for the dog. This negative feedback hormone system is responsible for 90% of the weight loss that is achieved with Slentrol. The other 10% is a result of the fat contained within the enterocytes leaving the body through the feces, as these cells are normally sloughed off every few days. Because there is no "free fat" in the feces, the consistency or volume of the stool is unchanged.