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ALAA on Labradoodle and Australian Labradoodle Health Issues: Addisons
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Addison's disease has been detected in a very limited number of the Australian Labradoodles and Labradoodles. Addison's disease is a disease that cannot yet be detected prior to the expression of the disease. The Poodle Club of America and UC Davis is currently undertaking research to detect DNA that will diagnose affected dogs and dogs that are carriers prior to the expression of the disease.
Until that time the only available breeding strategy for breeders of Poodles or Poodle mixes is to remove dogs that have actually produce Addison’s offspring from breeding programs and to study pedigrees to understand possible higher risk pedigrees. Lowering inbreeding and line breeding in these higher risk pedigrees to 0% will greatly enhance a breeder's ability to plan breeding strategies that include the breeding of these dogs. At this point, with such a minimal number of Australian Labradoodle and Labradoodle offspring with Addison's to consider, pedigree research is in its infancy.
The ALAA has noted in the ALAA database dogs that have produced offspring with Addison's. The ALAA has been informed as follows by experts on Addison's: “Heritability of Addison's disease was evaluated in 778 standard Poodles with known Addisonian phenotypes. Only 8.6 per cent of the Poodles enrolled in the study were classified as being Addisonian. Complex segregation analyses suggested that Addison's in the breed was influenced by an autosomal recessive locus. Both parents must be carriers for the puppy to inherit Addison's disease.”
As consumers you should be talking to your breeder about this issue, and they should be aware of current research. Health testing, awareness of these issues and selective breeding strategies are what set breeders apart, so select wisely.
The ALAA has been working with Dr. Dodds, the OFA, UC Davis, and other thyroid and Addison's experts to understand and aid in the study on Addison's.
We are excited to announce that UC Davis has invited the ALAA to participate in the UC Davis DNA study to find the DNA responsible for Addison's. This study will lead to a DNA test for Addison's.
If you have an assumed carrier or diagnosed Addison's Labradoodle or Australian Labradoodle, please confidentially contact the dog registrar at dogs@ilainc.com for your free test kit. This is not a test for Addison's as at present there is none. However, including these additional DNA samples in the DNA research will lead to a test being available sooner.
What is Addison’s?
It is the common name for hypoadrenocorticism, or adrenal insufficiency. It is a disease with symptoms that are common to many other ailments, making diagnosis difficult and sometimes a process of elimination. But once Addison’s is correctly diagnosed, a properly treated pet dog can live a normal, active life.
The adrenal, one on each kidney, is made up of two layers, the cortex and the medulla. The outer area, or cortex, secretes corticosteroid hormones such as cortisol and aldosterone. The medulla, part of the sympathetic nervous system, secretes epinephrine (adrenaline), which is generally not affected by Addison’s.
In Poodles and Poodle crosses the type of Addison’s disease is Secondary Addison's. Secondary hypoadrenocorticism is from failure of the pituitary to stimulate the adrenals with adrenocorticotropic hormone (ACTH). For definitive diagnosis the dog is given the ACTH stimulation or response test. This tests the ability of the adrenal glands to produce the corticosteroid hormone cortisol. An Addison’s affected dog can show signs at any age, but most likely between the ages of 4-7 unless illness and medication has shortened the time period at which Addison's would eventually be expressed.
Due to its late expression, lack of DNA testing prior to the actual expression of the disease and DNA testing for carrier dogs, an Addison's affected or carrier breeding dog could have a normal undiagnosed breeding life without the knowledge of the breeder.
The symptoms of Addison’s disease can be vague. More importantly, they are similar to the symptoms of many different problems. Initially, the dog may be listless, or seem depressed. Many dogs are described as just seeming off, or losing the normal sparkle in their eye. Lack of appetite is a good indicator. Other symptoms include gastro-intestinal problems like vomiting and diarrhea. Pain in the hindquarters, or generalized muscle weakness such as a dog that can’t jump onto the bed or couch as he has done in the past is not uncommon. Shivering or muscle tremors may also be present.
These symptoms may wax and wane over months or years making diagnosis difficult. If the adrenals continue deteriorating, ultimately the dog will have an acute episode called an Addisonian crisis. Potassium levels elevate and disrupt normal function of the heart. Arrhythmias can result and blood pressure drops to dangerously low levels. BUN and creatinine levels, generally indicators of kidney function, are often elevated. At this point many animals are diagnosed with renal failure, as the kidneys are unable to function properly. Typically animals are given IV solutions for rehydration, which may produce an almost miraculous recovery. This too, is a great indication that failure of the adrenals rather than of the kidneys is creating the symptoms.
Explanation and Breeding Strategies
The main goal of the Addison’s Breeding Strategies below are to ensure that we never produce any affected puppies, however until DNA testing is available no one can ensure any Poodle or Poodle cross is not a carrier or affected.
Therefore we must rely on two current detection methods:
- Assumed Carrier - Assumed carriers are any dogs that have produced Addison's offspring. If a Labradoodle, Australian Labradoodle or Poodle has produced an Addison’s offspring it is suggested that the dog no longer be bred.
- Higher Risk Pedigree - Higher risk pedigrees are those that have the same pedigree lines as those that are assumed carriers, and in many cases have been inbred or line bred thus increasing these higher risk pedigrees multiple times. In addition, higher risk pedigrees have assumed carriers closer in relation to the current breeding dog, i.e. parent or grandparent. Production of affected dogs should be prevented by ensuring at least one parent is not of a higher risk pedigree.
In summary, most of the Australian Labradoodle and Labradoodle breeding stock, even those with higher risk pedigrees may continue to be used for breeding, thus maintaining genetic diversity within our breed. Armed with this new information we can attempt to prevent breeding a puppy that will be affected with the disease as it ages.
Where do we recommend breeders go from here?
The ALAA recommends that breeders study their pedigrees and have a full knowledge of current assumed carriers. Poodle pedigrees should be studied in relation to the Poodle Club of America Addison’s database. Breeding dogs should have yearly CBC and TgAA testing via Antech NY labs or Dr. Dodds, Hemopets. If any offspring is diagnosed with this condition, notify the ALAA so that others may benefit from adjusting their breeding strategies.
All stud dogs should be tested yearly, and every breeder should require this test of those studs in service. Note that this does not indicate the dog is not a carrier or affected but will give yearly indicators that may lead to future detection.
This is not a required test for ALAA membership; however as breeders you are placing puppies with families that may in 4 to 7 years become affected with Addison's. We urge you to be proactive in your own program. Please email or fax your results to the ALAA dog registrar at dogs@ilainc.com so that the database can be maintained and others with common ancestors can benefit from the testing that is being done.
Email the ALAA with any questions: dogs@ilainc.com.
Click for Addisons All Breed Network, with information and support
It is suggest, and required for gold paw status, that ALAA Breeders test to OFA thyroid certification as follows:
General Procedures
Purposes - To identify those dogs that are phenotypically normal for breeding programs and to
gather data on the genetic disease - autoimmune thyroiditis.
Examination and Classification - Each dog is to be examined by an attending veterinarian and
have a serum sample sent to an OFA approved laboratory for testing according to the available
application and general information instructions (see website http://www.offa.org) . The
laboratory fee will be determined by the approved laboratory. Check with the referral laboratory
for special requirements for sample handling and tests for registry purposes. Samples received
within 48 hours do not have temperature requirements, but those in shipment for a longer period
of time must be received at 60oF or less.
Certification - A breed database number will be issued by OFA on all dogs found to be normal at
12 months of age or older. Ages will be used in the certification process since the classification
can change as the dog ages and autoimmune disease progresses. It is recommended that
reexamination occur every 18 months.
Preliminary evaluation - Evaluation of dogs under 12 months of age can be performed for private
use of the owner since a few dogs are already positive at that age. However, certification will not
be possible at that age.
Dogs with autoimmune thyroiditis - All data, whether normal or abnormal, is to be submitted for
purposes of completeness. There is no OFA fee for entering an abnormal evaluation of the
thyroid in the data bank. Information on results determined to be positive or equivocal will not
be made public without the explicit written permission of the owner or agent.
Thyroid abnormalities fall into several categories - Two types will be defined by the registry.
- ·Autoimmune Thyroiditis
- ·Idiopathically Reduced Thyroid Function
Autoimmune thyroiditis is known to be heritable. Those dogs with laboratory results that are questionable - therefore, not definitive, will be
considered as equivocal. It is recommended that the test be repeated in 3-6 months.
Classification: The method for classifying the thyroid status will be accomplished using state of the art assay
methodology.
Indices of thyroiditis:
- Free T4 by dialysis (FT4) - This procedure is considered to be the "gold standard" for
assessment of the thyroid's production and cellular availability of thyroxine. FT4D
concentration is expected to be decreased in dogs with the thyroid dysfunction due to
autoimmune thyroiditis. In 2006 the FT4D assay was no longer available and the Free T4 2
step procedure was substituted for registry purposes. The thyroid committee of OFA will
decide whether or not to continue using FT4-2s if a substitute dialysis procedure becomes
available.
- Canine Thyroid Stimulating Hormone (cTSH) - This procedure helps determine the site of
the lesion in cases of hypothyroidism. In autoimmune thyroiditis the lesion is at the level of
the thyroid and the pituitary gland functions normally. The cTSH concentration is expected
to be abnormally elevated in dogs with thyroid atrophy from autoimmune thyroiditis.
- Thyroglobulin Autoantibodies (TgAA) - This procedure is an indication of the presence of
the autoimmune process in the dog's thyroid. For the NSB corrected TgAA, <10 = negative, 10 to 25 = inconclusive, and
>25 = positive.
Certification
- Normal
- FT4 Within normal range
- cTSH Within normal range
- TgAA Negative (<10 = negative,10 to 25 = inconclusive)
- Positive autoimmune thyroiditis
- FT4 Less than normal range
- cTSH Greater than normal range
- TgAA Positive (10 to 25 = inconclusive,>25 = positive)
- Positive compensative autoimmune thyroiditis
- FT4 Within normal range
- cTSH Greater than normal range or equal to normal range
- TgAA Positive (10 to 25 = inconclusive,>25 = positive)
- Idiopathically reduced thyroid function
- FT4 Less than normal range
- cTSH Greater than normal range
- All other results are considered equivocal
The IALA/ALAA is a not for profit association dedicated to the Australian Labradoodle and Labradoodle breeds. Our health information is written in
association and/or in conjunction with the following resource(s), veterinarian(s) and association(s). As the ALAA is dedicated to informing our member
breeders as to the latest advances in health care, health testing and diagnostic medicines and not marketing an individual breeders program we are able
to aid our breeders in understanding these methods and to develop breeding strategies which in turn produce the highest quality puppies. To gain more
information on the programs, health testing and breeding strategies the ALAA has written, please ask our consults and current recourses:
Dr. Arun, Veterinarian Breeding Specialist, Summit Blvd Animal Hospital (ALAA consultant),
Dr. Dodds and
Hemopet (ALAA assisting in Dr. Dodds Addisons Research and using Hemopet/Dr. Dodds Thyroid Testing with personal assistance of Dr. Dodds),
OFA (Hip, Elbow, Patella and using recommended Thyroid and PRA prcd testing methods),
Dr. Kent Wallace, DVM, MSc, DACVR (OFA Certified Radiologist with the highly regarded Veterinary Multi-Imaging Group),
PennHIP, (hip testing)
BVA (Hip testing),
UCDavis (Addisons Research Initiative, ALAA is participating, genetic kit can be ordered via ALAA Heath Committee /UCDavis),
Dental Vet (Underbite and Orthodontics), and
Vet Dentistry ,
Optigen (PRA prcd) and
Articles,
CERF Canine Eye Registry Foundation
Antech Thyroid Testing and Addisons Research and
Update on Antech Thyroid Testing
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Australian Labradoodle Association of America, Inc.