Types Of Diabetes Mellitus In Dogs And Cats

In dogs and cats, diabetes mellitus is subdivided into three different types– I, II and III. 

Type I diabetes occurs most commonly in dogs.  The islet cells in these animals are destroyed and cannot produce insulin.  Treatment to control blood glucose levels in these patients require insulin injections just as do people with insulin-dependent diabetes mellitus. 

Type II diabetes is more common in cats and is similar to non-insulin dependent diabetes in humans.  Patients with this condition suffer from insulin resistance as well as problems secreting insulin.  Obesity is thought to be a trigger for this type of diabetes.  Although it is possible to control some cats with diet and oral hypoglycemics, others require insulin injections.

Type III diabetes is characterized by something within the patient that interferes with insulin and leads to glucose intolerance.  In my experience, Cushings’ Disease (Hyperadrenocorticism) is the most common cause of type III diabetes.  It may also occur secondary to glucocorticoid (prednisolone or prednisone) therapy.  Sometimes, this type of diabetes will often resolve after the drug is withdrawn or the Cushings’ disease is treated. 

Diets For Diabetic Dogs

There are three basic types of diets used in diabetic dogs; low carbohydrate, low-glycemic index and high insoluble fiber. In the first two diets, fat and protein are used to replace the calories normally obtained from carbohydrates.  Unfortunately, high fat content may cause pancreatitis, especially in animals that have already suffered from an episode.  The high protein diets are contraindicated in patients with liver and/or kidney problems.  Therefore, I prefer high insoluble fiber diets for diabetic dogs.  Please remember, this is my diet recommendation for dogs, not cats.  In my experience, diabetic cats do better on high protein/low carbohydrate diets.  

How does the insoluble fiber work?  Insoluble fiber cannot be digested by animals (including people) who have a single stomach digestive system.  Digestion requires multiple stomach compartments and mechanical degradation i.e., chewing cud, to break down these ingredients into useable material.  When the insoluble fiber passes through the gastrointestinal system of a monogastric animal, it slows the absorption of carbohydrates.  This is how the blood glucose levels are reduced.  Hill’s RD and WD, Purina DCO and Royal Canin Calorie Control CC High Fiber are a few examples of high insoluble fiber diets.

But the most important factor in diet for diabetic dogs is consistency.  In my opinion, the best regulation occurs when owners feed their dog the same amount of the same food at the same time twice a day.  This works because I can match the amount and type of insulin to the glucose load the dog ingests.  Regulation problems occur for two reasons:  The dog is not on a schedule and those notorious treats.  Treats are often loaded with carbohydrates that make regulation a nightmare.  I recommend no treats if possible.  If you must give your pet a treat, I recommend using a few kibbles of their own food.  If that is not acceptable, then vegetables low in sugar are the next best thing.  Avoid biscuits, crackers and other carbohydrate rich foodstuffs.

Chastain, C.B., et al. “Effects of Insoluble and Soluble Dietary Fiber on glycemic Control in Dogs with Naturally Occurring Insulin-Dependent Diabetes Mellitus”, Sm Anim. Clin. Endocrin. 200 Sep-Dec;10 (3):15.

Nelson, R.W., et al. “Effects of Dietary Insoluble Fiber on Control of Glycemia in Dogs with Naturally Occurring Diabetes Mellitus”, JVMA, Feb 1998; 212(3): 380-6.

Plague Found In Dogs And Cats Of New Mexico

This week I received an Animal Health Smartbrief from the American Veterinary Medical Association which announced pets in New Mexico contracted plague.  According to the New Mexico Department of Health, two dogs and two cats contracted the plague this spring.  The hantavirus is carried by fleas often found on rodents.  Fortunately, all of the animals recovered from the disease. 

To protect your family – both human and animal from this serious disease, the New Mexico Department of Health recommends the following:

1) Avoid contact with wild rodents, dead or alive.  Clean up brush or other debris where rodents nest.  Seal up cracks and holes to keep rodents out of your home.  Disinfect areas contaminated with rodent droppings and keep your pet’s food indoors, away from rodents.
2) Practice good flea control/prevention on your pets to keep fleas out of your home.
3) Seek immediate veterinary attention for sick pets.  Common signs include fever, lethargy, anorexia and swollen glands especially in the neck.
4) Seek immediate attention if you experience a sudden fever and swollen lymph nodes (also called glands).  Early treatment is the key to surviving this disease.

With the increase in plant growth from the wet winter fueling a surge in the rodent population, an increase in plague activity is expected.  Act now to protect yourself and your pets.   More information is available from http://nmhealth.org/ERD/HealthData/zoonotic.shtml.

“Department of Health Offers Advice to Stay Safe from Plague, Hantavirus: State Confirms Plague Pet Cases from Multiple Counties This Spring”, New Mexico Department of Health, April 16, 2010. 

Rebound Hyperglycemia (Somogyi Response) In Diabetic Animals

Whenever I counsel people about diabetes in animals, I always advise consulting a veterinarian before adjusting their pet’s insulin dosage.  Unfortunately, I met one client who ignored this advice.  Every day, the diligent woman checked her cat’s urine for glucose and pricked his ear to get an exact blood level.  Since the blood level was higher than she wanted and there was glucose in his urine, she increased the dose of insulin by a unit expecting the higher dose to control the glucose level.  When the levels were still too high at the next check, the frustrated woman increased the insulin even more.  Unfortunately, she did not understand the Somogyi response until it was too late for her cat.  She found him lying in his litter box, in a coma.    

Diabetes in animals is like diabetes in people.  The pet needs insulin injections to control their level of blood sugar.  If too much insulin is given, the blood sugar levels drop too low (hypoglycemia).  To counteract this life-threatening situation, the body releases hormones – primarily epinephrine and glucagon.  These break down glycogen reserves into glucose for release into the blood stream.  This phenomenon of the blood sugar dropping too low, below 80 mg/dl and then skyrocketing to over 300 mgl/dl is known as the Somogyi response.  It is also called rebound hyperglycemia or insulin-induced hyperglycemia.  

Unfortunately for the cat in the story above, the owner always retested his urine and blood during the “rebound” hyperglycemia, not during the life-threatening hypoglycemia.  She saw the high blood sugar results and gave more insulin because she did not understand what was really happening in her cat – the high dose of insulin bottomed out his blood sugar and then his body rebounded with its glycogen reserves.  

Therefore, I want to warn all caretakers of diabetic animals to check with your veterinarian before changing your pet’s insulin dose.  It is counterintuitive but a high blood glucose level might mask the fact that the pet needs less, not more insulin.         

Coated With Fur: A Vet’s Life Is Published!

After a year of writing and editing, I am pleased to announce that the book is published and available for your enjoyment!  Coated With Fur:  A Vet’s Life celebrates the deep bond between humans and animals.  Set in a veterinary practice, the book chronicles my triumphs and trials as a young woman owning her first animal hospital.  Experience each day as I did, from the joy of saving a dog’s leg to the agony of euthanizing a long-term patient.  Marvel at what it took to untangle a snake stuck in a doorway, scaring the society ladies in the waiting room.   
Through it all, embrace the unconditional love that exists when we open ourselves to the wonders of the human-animal bond!


To learn more or to purchase the book through Amazon.com please click here .

To all my friends, thanks for your constant support, words of encouragement and inspiration.  I hope the finished work was worth the wait.  Please give me your feedback.  I’m anxious to hear what you think of the book.  Enjoy! 

Arizona Desert Wildlife – Gambel’s Quail


Last spring, a pair a Gambel’s quail (Callipepla gambelii) moved into my backyard and set-up housekeeping in a flower pot.  The male placed small pebbles in a pile and the hen covered them with a few feathers.  Two days later, these eggs appeared.  I managed to sneak a photo of them while she left to forage for food.  For 22 days, the hen faithfully sat on her eggs while the male patrolled along the back fence.  Gambel’s quail form strong pair bonds and raise the chicks together.  

On the 23rd day, I heard peeping from the flower pot.  A day later, the hen abandoned the nest with 7 little chicks in tow.  One by one, the chicks jumped off the pot and landed with a thud on the patio.  Thankfully, none were injured.  The male flew down from the fence and escorted his little family out through the gate.  The chicks are difficult to photograph because of their small size and speed.  In most of my photo’s, the chicks are a blur of feathers.  This was the only decent photo I managed to obtain.     


Reference:  Thomson, M 2001. “Callipepla gambelii” (On-line). Animal Diversity Web. Accessed April 14, 2010.   

Snakes Are Out Of Hibernation In North Phoenix

Spring has hit the Valley of the Sun – flowers are blooming, birds are nesting and, unfortunately, the snakes are out.  When the snakes come out of hibernation they are very thirsty and hungry.  Once those needs are satisfied, their minds turn to mating.  The single-minded snakes go looking for love and sometimes end up in all the wrong places.  I have seen them crawl under and into golf carts while the unsuspecting players are on the green.  Like humans, they seem to loose a lot of their natural inhibitions and common sense when love is in the air!

Now that snake season is back, please watch your pets closely.  Keep them away from rock piles, washes and other “snakey” places.  Check your yard before allowing your pet to explore on their own.  If you live in a more natural area like I do, consider adding  several feet of hardware cloth or fine screen to an existing fence.  Don’t forget to address the gates and drainage holes in the fence too. 

Snake avoidance training is another option for protecting your dog.  For those of you who might be unfamiliar with this, a shock collar is used to teach the dog to avoid snakes.  Rattlesnakes, especially the Western Diamondback who is the most common rattlesnake in our area, have a strong musky smell.  When the dog smells the snake and approaches its cage, the handler delivers a small shock.  If the dog retreats, the shocks are over.  If the dog still advances, the intensity of the shock is increased. 

Please consider your dog’s temperament carefully before subjecting your pet to snake avoidance training!  It is not good for every dog.  In my experience, timid dogs do not do well with this type of training.  They feel the shock and freak-out without associating it with the snake.  Also, make sure you work with a reputable trainer who knows what they are doing.  Check multiple references and observe them in action before allowing them to handle your dog.  The extra time and effort is well worth it.   

Neonatal Isoerythrolysis And Cat Blood Types

Cat blood is broken down into three different blood types; A, B and AB.  Problems occur when an A type tom is bred to a B type queen.  All of the kittens will be type A because A is the dominant gene and B is the recessive.  When they nurse, the kittens receive antibodies from the queen through the colostrum.  The queen’s antibodies will attach to the kitten’s red blood cells, leading to their ultimate destruction.  Clinically, some of the kittens will die within hours of ingesting the colostrum while others might fail to thrive over several days leading to the term “kitten fading syndrome”.  

Once this immune reaction starts, it is difficult to control and save the kitten’s life.  That’s why I strongly recommend blood typing all cats before breeding.  Even though some breeds such as Siamese, Burmese, American Shorthair, Oriental Shorthair, Russian Blue and Tonkinese have a low incidence of type B, I still think it is a good idea to test as mutations may occur.  Blood type B is most prevalent in Devon Rex, Scottish Folds, British Shorthair, Exotic Shorthair and Cornish Rex.  Birmans are sometimes included in this group although I have not observed this clinically.        

What should you do if your cat is already bred and then you find out that the blood types between the queen and tom are incompatible?  If this situation occurs, do not let the kittens nurse from their mother during the first 24 hours.  Give them milk replacer or better yet, find a type B lactating queen and place them with her.  After the first 24 hours, gut closure occurs which means the kittens can no longer absorb antibodies through their digestive tracts.  At this point, they may be returned to the queen.  

Little, S.,  Feline blood Types and Neonatal Isoerythrolysis, Winn Feline Foundation.



Dogs Have Eight Blood Types – Does Neonatal Isoerythrolysis Occur In Dogs?

Based on the blood typing system used in the United States, dogs are divided into eight different blood types depending upon the antigens present on their red blood cells.  Dog erythrocyte antigen (DEA) 1.1 is the most important to me in clinical practice because it is the most antigenic.  Repeated exposure of a DEA 1.1 negative dog to a positive will stimulate antibody production.  This may occur if a positive male is repeatedly bred to a negative female or the female was given an unmatched blood transfusion.  The female’s immune system produces antibodies that are secreted into the colostrum.  The result is a condition called neonatal isoerythrolysis, destruction of the puppy’s red blood cells if it is DEA 1.1 positive.    

Although I have seen this condition in cats, especially purebred ones, I have never observed it in dogs.  My experience seems to reflect what others are seeing in veterinary medicine, that the condition is more common in cats and horses.  Having said that, I would still be very careful when breeding a female that had an unmatched blood transfusion.  Prior to breeding, I recommend knowing the blood type of the male and female to insure neonatal isoerythrolysis does not occur.  I would not want to put the health and well-being of the litter in jeopardy. 

Canine Blood Types – Significance in Transfusion, Animal Blood Bank, Jan. 18, 2006.      

Sago Palms Are Poisonous To Animals

After seeing so many poisonous plants for sale at the local home improvement store, I decided to start a new category dealing with poisonous plants.  The number of poisonous plants used in landscaping and as indoor plants is absolutely staggering.  Before you bring any plant into your house, check to see if it is safe for pets and small children. 

Sago palms, also called cycad palms are very poisonous.  The seeds, fruit and base are loaded with cycasin, a toxin that causes liver failure.  Ingestion of just one seed may cause death in a dog.  Vomiting, abdominal pain, diarrhea, depression and neurologic signs develop within a few hours of ingestion.  Abnormalities in the blood work lag behind clinical signs by about 24 hours making it hard to diagnose.  Death occurs within hours to days depending upon the amount of poison ingested.   

In a study of 60 dogs with sago palm toxicosis, 95% of them developed liver failure and gastrointestinal problems.  Neurologic signs including posterior paresis, depression, problems with coordination called ataxia and seizures occurred in 50% of the animals studied.  Unfortunately, once clinical signs occur, one third of dogs will die. 

If your pet has been exposed to a sago palm, bring them to your veterinarian for immediate decontamination.  Do not take a wait and see approach with this poison.  If you have these plants in your yard or house, I must suggest you remove them immediately to prevent an accidental poisoning.  The following pictures will help you identify this plant.


Albretson, JC, et al, “Cycad palm toxicosis in dogs – 60 cases (1982-1997)”, JAVMA 1998 Vol 213 (1) pp. 99-101.