Fall 1999 © TheDogPlace.org / Liz Harrell - There are five types of hypothyroidism observed in the dog. Of these, three are of the "goiter" type.  "Goiter" simply means that the thyroid gland is enlarged. Enlargement may be due to a reaction to decreased thyroid hormone levels in the blood.  There may be a lowered level of iodine in the system (this is usually seen only in dogs fed an all meat diet) or the thyroid gland may be affected by tumors, either benign or malignant but these are rare.

The two types of non-goiterous hypothyroidism are primary and acquired. Primary is due to insufficient functioning of thyroid tissue which may mean there is too little tissue available. In short, thyroid atrophy. This situation usually appears in older adults. Why the thyroid should atrophy is not understood, but is considered to be an autoimmune involvement such as the type sometimes observed in Beagles.

The last type is linked with pituitary insufficiency. This may occur because the pituitary gland is not secreting normally due to destruction of its parts involved with various types of tumors. In these cases, the pituitary can no longer produce the hormones required by the body, or at least produces them on a reduced basis.

These are all serious problems and tricky to diagnose because the symptoms are also the symptoms of other diseases such as Cushings Syndrome, diabetes mellitus, etc. Therefore, a series of tests should be made to verify what the real cause of the problem might be.

These are very complex tests and, for accuracy, duplicate tests should be run simultaneously – one set per lab. In any complex disease, this is a good rule to follow because one must take into account the fallibility of the technicians, the lab procedures and the interpretation of the results. Some lab techs are too busy to take the necessary time or care, some labs have loose standards because of the pressure of too much business and the vet trying to evaluate the labs findings may have to read between the lines to get a clear picture of the situation.

As an example, consider this ... an animal suspected of lupus had five tests run. That is, five slides were prepared. On only two of those slides did the lupus cell appear and those were found only after approximately 20 minutes of study on each slide. Had the diagnosis been based on the first three slides only, the dog would have been declared free of lupus and not properly treated. 

Thyroid deficiency takes a long time to develop. The lethargy is usually thought to be the youngster maturing. Coarse hair coat might be attributed to fleas, shedding, etc. Reduced appetite, wanting to be where it's warm all the time and lack of alertness can be looked upon as the first signs of old age.  It's easy to dismiss these signs as nothing serious -- which means the dog is really into the problem by the time he gets to the vet.

I have yet to see an Akita with inherited thyroid problems. I have seen or heard of several with depressed thyroid function due to the diet the dog has been fed. In farming communities, the effect of soybeans in the diet of farm animals has been known for a long time. Cows, pigs, etc. fed long-term diets of soybean based foods can develop thyroid deficiencies. The treatment usually consists of changing the diet. Nothing more. Within 30 days, a reversal of the situation is usually evident.

However, there is one other factor that needs to be explored. The companies manufacturing animal feeds use toxins to extract the oil from the soybeans. These toxins are lethal.  S-(dichlorovinyl)1-cystine is supposedly not being used anymore, but the chemicals now being used in its place are just as lethal. Residuals of these toxins remain in the feeds and, over a period of time, the animals will show symptoms of lethargy, lack of interest, lack of appetite, affected hair coat, etc. 

I questioned several vets about whether they had read material in their publications about toxins in the feed and not one could remember having seen any. However, they all felt that the possibility of residual toxins in dog food was probable or at least something to be considered.

To give you an idea of how toxic these chemicals are, consider this: A large manufacturer of animal feeds in the midwest started dumping the residue of these toxins in the local river. In a very short time, all the fish and associated wildlife in the area were dead. The county agencies sued and from that point on, the toxic wastes had to be eliminated in a different way. The settlement was well into six figures so you can judge from that how serious the problem was.

It has become the fashion to treat any dog presented that shows a coat problem with a 30-day supply of L-thyroxin, etc. What is amazing is that most of the dogs treated in this manner show some improvement in their coat problem which leads to the assumption that it must have been a thyroid problem. Unfortunately, the improvement is short-lived and the dog will revert to the same condition he was in prior to the hormone treatment. In short -- it's unwise to initiate hormone treatment without adequate testing to verify the disease.

To the dog owner who realizes how soybeans might affect his dog and who takes great care in buying the proper soy-free kibble, may I make the following  suggestion: If you add to that kibble a canned dog food, PLEASE read the label on that canned food! Nearly every canned dog food on the market contains soy oil. You would be wise to either skip the additives or use only something cooked fresh. If you use coat conditioners, you must also read the labels because some of them contain soy oil, too.

Liz Harrell is the Grand Lady of the Akita breed.   She and her late husband Al were amongst the founders of the Akita Club of America in 1956 and the Akita Rescue Society of America in 1977.  Their "Akita Tani" kennel name was registered with the AKC in 1954. 

Mrs. Harrell passed away on June 20, 2001.

For more information on Thyroid Disease, hypothyroidism, diagnosis and treatment, and whether thyroid supplementation help other conditions, see Thyroid Diagnosis and Treatment, In-depth information, part 2 of 2 by chemist, international Judge, GSD breeder Fred Lanting

Also Hypothyroidism, Cause & Cure, what your vet won't tell you, by Hall Of Fame Akita breeder BJ Andrews

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