We can assure you that there is nothing normal about being overweight.

Why Obesity is Bad

A common justification for over-feeding treats is that a pet deserves a higher quality of life as a trade off for longevity. While this might on some level makes sense (after all, a pet munching on a treat is certainly getting a great deal of satisfaction from doing so), the other consequences do not make for higher life quality in the big picture. Here are some of problems that obese animals must contend with while they are not enjoying their treats and table scraps.

Arthritis

The over-weight animal has extra unneeded stress on joints, including the disks of the vertebrae. This extra stress leads to the progression of joint degeneration and creates more pain. Weight management alone decreases and can even eliminate the need for arthritis medications. The problem is compounded as joint pain leads to poorer mobility, which in turn leads to greater obesity.

Respiratory Compromise

The obese pet has a good inch or two of fat forming a constricting jacket around the chest. This makes the pet less able to take deep breaths as more work is required to move the respiratory muscles. Areas of the lung cannot fully inflate, so coughing results. The pet also overheats more easily. Many cases of tracheal collapse and chronic cough can be managed with only weight loss.

Diabetes Mellitus

Extra body fat leads to insulin resistance in cats just as it does in humans. In fact, obese cats have been found to have a 50% decrease in insulin sensitivity. Weight management is especially important in decreasing a cat’s risk for the development of diabetes mellitus.

Hepatic Lipidosis

When an overweight cat goes off food or partially off food because of illness or psychological stress, body fat is mobilized to provide calories. Unfortunately, the cat’s liver was not designed to process a large amount of body fat. The liver becomes infiltrated with fat and then fails. A stress that might have been relatively minor, such as a cold, becomes a life-threatening disaster.

Reduced Life Span

A study of age-matched Labrador retrievers found that dogs kept on the slender side of normal lived a median of 2.5 years longer than their overweight counterparts.

Unwillingness to Accept Therapeutic Diets

If the pet should develop a condition where a therapeutic diet is of great benefit, the pet that has been maintained primarily on a diet of table scraps may be unwilling to accept commercial pet food of any kind, much less a food modified to be beneficial for a specific disease process. This unwillingness will hamper treatment.

Increased Surgical/Anesthetic Risk

Obesity poses an extra anesthetic risk because drug dosing becomes less accurate. (It is hard to estimate a patient’s lean body mass for drug dosing if it is encased in a fat suit.) Furthermore, anesthesia is inherently suppressive to respiration and adding a constrictive jacket of fat only serves to make proper air exchange more challenging. And still further, surgery in the abdomen is hampered by the slippery nature of the extra fat as well as difficulty visualizing all the normal structures through the copious fat deposits. One never knows when a pet will require an emergency surgery (to say nothing of regular teeth cleanings).

So is the enjoyment of all those extra treats really worth it?

How Did My Pet Get So Fat Without Eating That Much?

You might think weight management might be easier for a pet than it is for a human. After all, the pet relies completely on someone else for feeding and exercise so it should follow that if the humans in control can regulate feeding and exercise, the pet should lose weight. It seems like this would be true but, as with humans, there is tremendous individuality with how different pets store the food they have eaten. Beyond this, sometimes it is hard to know what a pet is eating or the owner may not have a good sense for how much should be fed. Here are some factors involved.

If you do not have a cup measure, you can often get one from your veterinarian’s office as most manufacturers of reducing diets for pets provide free cup measures.

onsider measuring food with a gram scale. This a far more accurate way of measuring food amounts compared to cup measures.

The Package Guidelines are just Guidelines

Many packages of food include on their label some sort of feeding schedule that indicates how much food should be fed to a pet of a certain weight. This information is also available on most pet food web sites as well. The problem is that each pet is an individual and just as one person weighing 150 lbs can be obese and another person of the same weight may be skinny, the same is true of pets. These guidelines are meant as a starting point only. If your pet is too fat on the recommended feeding schedule, then you should reduce the amount of food or change to a diet that is higher in fiber so that a satisfying volume of food can still be eaten without adding calories.

Genetics

Some animals simply have the genes that predispose them to obesity. Dog breeds with genetic tendencies towards obesity include the: Golden Retriever, Cocker Spaniel, Dachshund, Beagle, Shetland Sheepdog, Boxer, Cairn Terrier, Basset Hound, and Labrador Retriever.

Children at Home

It is almost impossible to keep children from providing extra treats to their dog. This may include snacks spilled during play (pets have no “five-second rule”) or purposely feeding the pet unwanted food under the dining table. Similarly, pets that are allowed to roam (usually cats) often find food left out by neighbors, either to purposely feed their own pets or strays, or as unsecured trash. It is almost impossible to control the diet of an outdoor cat.

Low Metabolism

Some pets do not burn calories efficiently; they simply have a slow metabolism. This might be genetic as mentioned or it might be the result of a disease such as hypothyroidism or Cushing’s disease. Testing for health problems such as these is helpful to get the best treatment for resolution of the obesity. It seems like increasing exercise and eating a healthier diet would be easy to accomplish for a pet but it generally does not turn out that way.

Underestimating the Power of Treats

Many people express their affection for the pet by providing regular treats, and the pet happily obliges by begging or even performing cute behaviors. For some people, feeding treats to the pet constitutes a major part of the human-animal bond and they do not wish to give it up or reduce it. Pet treats are often high in calories, though, and four or five treats readily converts into an extra meal’s worth of added fat. Free feeding of dry food encourages the pet to snack as well; meal feeding represents better calorie control.

Treats should not exceed 10% of the pet’s feeding allotment.

Neutering

Sterilizing a pet is good for public health (fewer strays means fewer dog bites, less public resources needed for animal shelters etc.), good for a better house pet (less urine marking, tendency to fight or roam), no unwanted litters, reduced risk of many diseases, etc. The change in the hormonal picture, though, creates a tendency to form more fat cells (creating increased fat storage capacity – especially in female cats), and typically slows metabolism. Spay/neuter is a excellent time to switch from free feeding to meal feeding.

Evaluation by Body Score

Sometimes it is hard to recognize that your pet is overweight as the weight gain has come on gradually or it is hard to actually accept that your pet is more than just a little chubby and is now fully obese. To assist in this evaluation, body condition scoring has been developed and is fairly easy to accomplish. There are two scoring systems: a five-point system (where three out of five is considered optimal) and a nine-point system where four to five out of nine is considered optimal).  To evaluate your pet, feel for a small amount of padding over the ribs. It should be possible to feel the ribs and there should be a small tuck in the belly where the hind legs meet the body. 

See the body condition charts for dogs and cats.

What can be Done: Diet and Exercise

This sounds simple, but in fact when you simply try to cut back on food, it just does not seem to work. Begging for food can result plus simply reducing the amount of a regular diet (one not meant for weight loss), can lead to deficiency in vitamins or minerals.

As with humans, a more formal approach seems to work best. This means feeding a prescription diet made for weight loss (typically “lite” or “less active” diets are meant to prevent weight gain, not actually cause weight loss), feeding a measured amount, and coming in for regular weigh-ins at the vet’s office.

This means:

• There must be control over what the obese pet eats. That’s easy enough if there is only one pet and roaming is not allowed, but trickier if there is more than one pet in the home. Use your ingenuity to feed the pets separately.
  
• Feed in meals. Leaving food out encourages snacking. Feeding in meals makes it easier to feed multiple pets different foods or different amounts of food.
  
• Commit to regular weigh-ins. Know what the goal weight is and how long it should take to reach this goal/or how to tell if the pet is on target. It is important not to try to go too fast. If the weight loss is not on track, sometimes it is necessary to feed more rather than less. Your veterinarian may need to be in contact with the clinical nutritionists at the pet food company so as to make the best recommendations.
  
• Consider interactive toys that can be used when you are not home or where your own participation is minimal.

Be sure to rule out health issues that might specifically cause obesity as an initial step in obesity management.

Nutrigenomics

Nutrigenomics is the study of how food influences the expression of genes and how genes influence the disposition of nutrients. This field is still in its infancy but is rapidly developing such that one day nutritional programs can be designed based on one’s own individual genetic composition. We all have seen how different people metabolize the same food in completely different ways and how changing to a similar diet can have varying effects among individuals.

There is currently only one commercial diet on the market that uses principles of nutrigenomics to activate genes of fat-burning and create a fat burning metabolism and that only available through veterinary clinics. This food system employs dry food, canned food, and treats in any combination but in amounts determined by the pet’s initial body composition and calculated healthy weight. This approach has not been found to be more effective with weight loss over the more traditional high fiber diets but at the end of the program when the desired weight had been achieved, the animals on the nutrigenomic diet had been metabolically altered to reduce storage of consumed fat. Pets on traditional weight loss plans were not metabolically altered and were still “fat storers” and potentially ready to regain the fat stores they had worked so hard to lose. This food is for sale only through veterinarians so if you are interested in this concept, talk to your veterinarian.

Do it Yourself without a Therapeutic Diet

Therapeutic diets are available only through veterinary clinics and authorized diet delivery services. These types of foods are likely to cost more and/or be less convenient to obtain than foods available at the grocery store or pet supply store so a pet owner may be tempted towards do-it-yourself weight loss. As discussed, weight loss often turns out to be more complicated than you imagine. If the problem is simply cutting out treats, adding more exercise or in some way changing the human behavior that led to the pet’s weight condition, then you may have a good chance at getting results. If the problem is the pet’s metabolism, then it may be an uphill battle. Regular weigh-ins are still crucial and the pet should not lose more than two percent of body weight per week. High-fiber diets tend to work best for dogs while low-carbohydrate diets tend to work better for cats.

For more specific information, consult your veterinarian, and see the Association for Pet Obesity Prevention.

(Dogs and cats have a sense of smell at least 1,000 times more accurate than ours and this is their primary means of perceiving the world.)

Anatomy First

The fibers making up the lens come together in the center of the lens, forming a “Y” shape that is sometimes visible when one looks into the eye. These Y-shaped lines are often called the sutures of the lens.

The lens is enclosed in a capsule that, if disrupted, allows the immune system to see the lens proteins for the first time, recognize them as foreign, and attack. The resulting inflammation (a form of uveitis) is painful and can be damaging to the eye. A cataract can result from this inflammation or from any of the numerous other reasons listed below.

A cataract is an opacity in the lens.

A Note on Diabetes Mellitus in Dogs

Cataracts can be congenital (born with it), age-related; of genetic origin (the most common cause); caused by trauma; dietary deficiency (some kitten milk replacement formulas have been implicated); electric shock; or toxins. The patient with a cataract is not able to see through the opacity. If the entire lens is involved, the eye will be blind.

Many things can cause the lens to develop a cataract. One cause is diabetes mellitus. In this condition, the blood sugar soars as does the sugar level of the eye fluids. The fluid of the eye’s anterior chamber is the fluid that normally nurtures the lens but there is only so much glucose that the lens is able to consume. The excess sugar is absorbed by the lens and transformed into sorbitol. Sorbitol within the lens unfortunately draws water into the lens, causing an irreversible cataract in each eye. Cataracts are virtually unavoidable in diabetic dogs no matter how good the insulin regulation is; diabetic cats have alternative sugar metabolism in the eye and do not get cataracts from diabetes.

What Else Could It Be?

Many owners cannot tell which portion of the eye looks cloudy. Cloudiness on the cornea, as caused by other eye diseases, can be mistaken for a cataract by an inexperienced owner. Also, in dogs, the lens will become cloudy with age as more and more fibers are laid down, as described above. Nuclear sclerosis, as described, can mimic the appearance of a cataract, yet the eye with this condition can see and is not diseased. It is a good idea to have your veterinarian examine your pet if you think there is a cataract, as you could be mistaken.

Why is it Bad to Have a Cataract?

The area of the lens involved by the cataract amounts to a spot that the patient cannot see through. If the cataract involves too much of the lens, the animal may be blind in that eye and there could be cataracts in both eyes, which means the pet could be rendered completely blind.

A cataract can luxate, which means that it can slip from the tissue strands that hold it in place. The cataractous lens can thus end up floating around in the eye, where it can cause damage. If it settles to block the eye’s natural fluid drainage, glaucoma (a buildup in eye pressure) can result, leading to pain and permanent blindness. A cataract can also cause glaucoma when it absorbs fluid and swells so as to partially obstruct fluid drainage.

Cataracts can begin to dissolve after they have been there long enough. While this sounds like it could be a good thing, in fact, it is a highly inflammatory process. The deep inflammation in the eye creates a condition called uveitis, which is in itself painful and can lead to glaucoma. If there is any sign of this type of inflammation in the eye, it must be controlled before any cataract surgery.

A small cataract that does not restrict vision is probably not significant. A more complete cataract may warrant treatment. Cataracts have different behavior depending on their origin. If a cataract is a type that can be expected to progress rapidly (such as the hereditary cataracts of young cocker spaniels) it may be beneficial to pursue treatment (i.e. surgical removal) when the cataract is smaller and softer, as surgery will be easier.

What Treatment is Available?

Determining if a Dog is a Candidate for Cataract Removal

Obviously, the patient must be in good general health to undergo surgery; diabetic dogs must be well-regulated before cataract surgery. Also, it should be obvious that for a patient to be a good candidate for surgery, the patient must have a temperament conducive to getting eye drops at home. 

Pre-anesthetic lab work can be done with the patient’s regular veterinarian. Some ophthalmologists prefer that patients have their teeth cleaned before surgery to minimize infection sources in the eye.

A complete examination of the eye should be performed. If your veterinarian is not comfortable treating cataracts or does not have the appropriate equipment, your pet may be referred to a veterinary ophthalmologist.

It is impossible to see the retina through a cataract; an electroretinogram test can determine if the eye has a functional retina and can benefit from cataract surgery. Ultrasound of the eye can be used to look for retinal detachments. If the eye has a blinded retina, there is no point in subjecting the patient to surgery. Inflammation in the eye will require treatment before surgery. Sometimes, other eye drops are prescribed for a period before surgery depending on the veterinarian’s preference.

Cataract Removal: Phacoemulsification and Surgical Removal

In either case, the eye must be paralyzed during surgery to prevent eye movement or even blinking at a critical moment. Nerve blocks can be used to paralyze the eye, or specific medications can be used to paralyze the entire patient (in which case a mechanical ventilator is used to breathe for the patient during surgery).  After the lens is removed, an artificial lens is implanted. (Without the prosthesis, the dog’s vision will be approximately 20/800, and objects will appear to be reversed, as in a mirror.)

After surgery, the pet must wear an Elizabethan collar for a good three weeks, and eye drops to reduce inflammation will be needed for several months. A harness may be recommended for walks instead of a collar to reduce pressure on the head and eye from pulling. There will be a schedule of recheck appointments.

Complications

Some degree of uveitis (deep inflammation) is unavoidable. This can cause a pupil constriction reaction that can increase the risk of scarring within the eye. Eye drops to keep the pupil dilated are usually effective in preventing this but not always. Inflammation in the eye will resolve over weeks to months after surgery. The success rate is higher for cataract surgery if there is minimal inflammation in the eye prior to surgery, thus pre-operative anti-inflammatory eye drops are frequently prescribed.

Another complication involves the development of opacities on the remaining lens capsule. In humans, laser surgery is used to remove the lens capsule, but in dogs, the capsule is too thick for this. Some ophthalmologists prefer to remove the capsule as a preventive measure. The portion of the capsule that is involved in this reaction is present in young dogs but not in adult dogs.

Bleeding after surgery can be an enormous complication and can easily be caused by excess barking or activity after surgery. Small bleeds are of little consequence, but a large bleed could ruin vision.

Glaucoma can develop at any time after cataract surgery. This complication is not only blinding but painful as well. The risk of this complication has been decreased by placing a prosthetic lens (a formerly uncommon but now fairly standard procedure) but dogs who start off with hypermature (dissolving) cataracts or have an unusually long surgery time tend to have an increased risk for this complication.

Overall, a 95 percent vision rate is described immediately after cataract surgery with 80 percent having long-term vision success.

Before embarking on the adventure of cataract surgery, be sure to obtain a clear explanation from your veterinarian or ophthalmologist of exactly what the home care will involve.

What if the Cataract Goes Untreated?

A cataract by itself does not necessarily require treatment. If there is no associated inflammation or glaucoma and the only problem is blindness, it is perfectly reasonable to have a blind pet. Blind animals have good life quality and do well though it is important not to move furniture around or leave any hazardous clutter in the home. Some dogs, however, become anxious or even aggressive when they lose their vision. Restoring vision for the pet is weighed against risk and expense and is a decision for each owner to make individually. Many cataracts will progress to a hypermature state where they will begin to dissolve as described and anti-inflammatory eye drops are needed as mentioned. 

Can Eye Drops Dissolve Cataracts?

Products containing N-acetylcarnosine have been marketed to dissolve cataracts and have led to a great deal of false hope. N-acetylcarnosine is an antioxidant eye drop that may have beneficial effects on the eye but they do not include any sort of dissolution of a mature cataract. For smaller cataracts, it may be possible to dilate the pupil so that the pet can see around the cataract but there is some controversy about doing so as these medications have other effects on the eye.