Health Issues/Research
Mission Statement
To promote the health and well being of the purebred Shetland Sheepdog. We plan to accomplish this goal through research and public education. We encourage all breeders and owners of Shetland Sheepdogs to be aware of health problems in the breed and to use all resources available to them to ensure the lifelong health and well being of all Shelties in their care. We will function as a public resource and clearing house for information related to health concerns as they pertain to the purebred Shetland Sheepdog.
ASSA Research Committee Chair: Mary Mahaffey
CONTENTS
ASSA Health Activities
Notice on Genetic Diseases in Shelties
Canine Health Information Center (CHIC) Program for Shelties
Shetland Sheepdog Health Survey
CHIC DNA Repository
Current Research Projects
Articles
Current Research Projects
Research on Canine Cancer
Dermatomyositis (DM)
Gallbladder Disease and Hypercholesterolemia Study
Leishmaniasis Research Information
Bladder Cancer Research
Undescended Testicles (Cryptorchidism) Research
Investigations into the Genetic Mutations Causing Two Different Dental Anomalies in Shelties
“Lance” Canine Teeth and Abnormal 3rd Incisor Teeth
Lance Canine Submission Form
Abnormal 3rd Incisor Submission Form
Articles
To Test or not to Test?
Considering breeding your Sheltie?
AKC Canine Health Foundation Grants
Grant#748:SNP Association Mapping of Canine Epilepsy
Notice on Genetic Diseases in Shelties
March 2008
Concerned breeders of Shetland Sheepdogs are striving to breed healthy Shelties and decrease the incidence of heritable diseases in the breed. Hip Dysplasia, thyroid disease, eye diseases, Dermatomyositis (Sheltie Skin Syndrome), von Willebrand’s disease (vWD), and epilepsy are some of the known health problems of the breed. Although these problems are NOT COMMON in the breed, the Board of Directors of the American Shetland Sheepdog Association recommends that questions about the health of the dog and its relatives be asked when inquiring about the purchasing of a puppy or adult, use of a stud dog and/or the acceptance of a brood bitch.
Does the dog and its relatives have CERF and OFA or PennHip numbers or an exam form signed by a qualified veterinarian for these tests? Does the Sheltie (adult or puppy) or its relatives have any of the above mentioned problems? Questions should also be asked about abnormal tooth alignment or missing teeth and crypt-orchidism (retained testicle).
The American Shetland Sheepdog Association (ASSA) is NOT advising you not to buy a puppy or breed to a stud dog if these conditions exist, but wants puppy buyers and breeders to be aware of genetic problems in the breed so that informed decisions can be make when buying or planning a breeding.
CanineHealth Information Center (CHIC)
Program for Shetland Sheepdogs
April 2008
Health problems, in general, are not common in Shelties; however, testing of breeding stock is a recommended practice to keep the incidence of certain problems as low as possible. It must be remembered that dogs are animals, not machines, and on average, every dog has 4 to 5 defective genes.1 Congenital and/or hereditary problems will occur no matter how conscientious a breeder is. Nonetheless, breeders should strive to breed Shelties that are a combination of beautiful breed type and good health.
The Canine Health Information Center (CHIC) www.caninehealthinfo.org/chicinfo.html is a canine health database program jointly sponsored by the AKC/Canine Health Foundation (AKC/CHF) and the Orthopedic Foundation for Animals (OFA). Its purpose is to assist breeders in breeding healthy dogs and being a central resource of health information for breeders, owners, and researchers. Over 100 breed clubs participate in the program. The national club for each participating breed recommends health tests to be performed in dogs used for breeding. The number and types of tests are tailored to the needs of each breed. Dogs that have had the required tests will receive a CHIC number, and the CHIC database can be searched for dogs having CHIC numbers. Additional health tests may be recommended, but are considered optional for that breed. Normalcy is not required for participation in the CHIC program; abnormal results of any test are only released to the public with owner permission. As new tests become available, the list of required and optional tests may be altered. Participation in the CHIC program is voluntary.
Breed requirements for Shetland Sheepdogs are as listed below and on the CHIC Shetland Sheepdog web page. www.caninehealthinfo.org/brdreqs.html?breed=SS
Required tests:
- Hip dysplasia (OFA or PennHIP)
- Eye clearance (Canine Eye Registration Foundation, CERF)
- von Willebrand's Disease (VetGen, test results registered with the OFA)
- Multiple drug sensitivity (MDR1) DNA test (Washington State University, results registered with the OFA)
Optional tests:
- Autoimmune thyroiditis (OFA evaluation from an approved laboratory, test results registered with the OFA)
- Collie eye anomaly DNA test (Optigen, test results registered with the OFA)
- Elbow dysplasia (OFA)
- Congenital cardiac database (OFA evaluation by board certified cardiologist or internal medicine specialist)
- American Temperament Testing Society, TT title, (test results registered with the OFA)
Brief Explanation of the Tests
Required tests:
Hip Dysplasia Evaluation – As of March, 2008, Shetland Sheepdogs rank 129th of 150 breeds of dogs evaluated for hip dysplasia by the Orthopedic Foundation for Animals (OFA) www.offa.org. Of 16,223 Shelties evaluated, 4.8% were dysplastic. OFA certification or PennHIP evaluation of the hips (x-ray examination) is on the required list for the CHIC program because hip dysplasia can be a crippling disorder, and one affected influential dog used in breeding programs could increase the incidence in Shelties. OFA hip evaluation results are automatically included in the OFA database with no extra charge. More information can be obtained by clicking on the following link http://www.offa.org/hipinfo.html .
Eye Certification with the Canine Eye Registration Foundation (CERF) http://www.vmdb.org/cerf.html – Eye abnormalities can occur at any age. Ophthalmic examination can detect a variety of congenital abnormalities, including Progressive Retinal Atrophy (PRA) and Collie eye anomaly (CEA), which also occurs in Shelties. The merling gene may make it difficult to detect mild cases of CEA by ophthalmic examination because merling is normally associated with less pigmentation of the eyegrounds (back of the eye). Also, the CEA lesions (chorioretinal hypoplasia) in some mildly affected dogs may be partially masked as the eye matures, so may be missed at 8-10 weeks of age or later. Thus examination at an early age, about 5-8 weeks of age, is recommended. Because the onset of other eye diseases (such as cataracts and retinal degeneration) can occur at any age, dogs should be reexamined periodically. A more detailed discussion can be found at: http://www.vmdb.org/aug02.html#d xspot . Ideally, each dog should be examined within the preceding 12 mos. of being bred. According to the link above, the likelihood of a genetic problem showing up after age 9 years is low. The test is an eye examination performed by a board certified veterinary ophthalmologist. Results are automatically included in the OFA database with no extra charge.
von Willebrand’s Disease (vWD) DNA Test – vWD is a potentially serious bleeding disorder and one that can be kept from being a major problem in the breed by having this one-time DNA test done. According to the VetGen website (http://www.vetgen.com/canine-vwd3.html ), the incidence of vWD in Shelties as of January, 2005 is: Clear – 92%, Carrier - 7%, Affected – 1%. Dogs “Clear By Parentage” (first generation - see OFA website for detailed policy) would be accepted into the CHIC program. The test can be performed using DNA from cheek brush collection that can be mailed-in by the owner.
Multiple Drug Sensitivity (MDR1 gene) DNA Test – This DNA test identifies dogs that are sensitive to several medications. Shelties, Collies, Australian Shepherds, and Border Collies are a few of the breeds with this genetic mutation. Several commonly used drugs, ex. antiparasitic drugs (some used in heartworm preventatives), tranquilizers (acepromazine), and anti-diarrheal drugs (Imodium®) are a few of the drugs that may affect dogs with this genetic mutation. This test would provide useful, practical knowledge for every Sheltie owner, since knowing the status of each dog as clear, carrier, or affected would help a veterinarian determine which drugs to use or avoid in a particular dog. As of March, 2008, 448 Shelties have been tested (Washington State University) with 11% being heterozygous (carriers) for the MDR1 mutation, and 1 % homozygous for the MDR1 mutation. Heterozygous dogs (carriers) exhibit sensitivity to drugs that is similar to or less than that of homozygous (affected) dogs. A complete list of drugs that may affect dogs with the MDR1 gene can be found at the following link: http://www.vetmed.wsu.edu/depts-VCPL/drugs.aspx. More information on the topic can be found at: http://www.vetmed.wsu.edu/depts-VCPL/ and http://www.ashgi.org/articles/mdr1.htm . Dogs “Clear By Parentage” (first generation - see OFA website for detailed policy) would be accepted into the CHIC program. The test can be performed using DNA from cheek brush collection that can be mailed-in by the owner.
Optional tests:
Autoimmune Thyroiditis – Autoimmune thyroiditis may lead to hypothyroidism. It is generally accepted that autoimmune thyroiditis is inherited; however, studies to determine mode of inheritance either have not been performed or are inconclusive. 2 According to the OFA website, where breed results for the Michigan State University Laboratory are listed, Shetland Sheepdogs are 24th of 140 breeds (in which 100 or more evaluations have been performed) with autoimmune thyroiditis. Of 14,110 Sheltie evaluations, 12.7% were positive for autoimmune thyroiditis. From the OFA website, “Since the majority of affected dogs will have autoantibodies by 4 years of age, annual testing for the first 4 years is recommended. After that, testing every other year should suffice. Unfortunately, a negative result at any one time will not guarantee that the dog will not develop thyroiditis.” The ASSA Research Advisory Committee recommends that, at a minimum, dogs be tested at 2, 4, and 7 years of age. A blood sample is needed for this test. The Committee debated whether or not this test should be on the required list as it should be repeated multiple times over the life of a dog, and it is more expensive than other procedures that should be repeated such as eye certification. More information on autoimmune thyroiditis can be found at the following links: http://www.offa.org/thygeninfo.html and. http://www.upei.ca/~cidd/intro.htm .
Collie Eye Anomaly (CEA or Choroidal Hypoplasia) DNA Test - CEA is a recessively inherited ocular anomaly that affects development of a portion of the eye. Homozygous recessive dogs may have lesions ranging from mild to severe. Heterozygous dogs will be phenotypically normal. Choroidal hypoplasia, coloboma, and retinal detachment are features of the disease. It occurs in Shetland Sheepdogs as well as other herding breeds. The CEA DNA test can distinguish between normal, carrier, and affected dogs. Unlike CERF examination, it is indifferent to the age of the dog or the presence of the merle gene. The ASSA Research Advisory Committee encourages breeders to consider this test for their breeding stock to keep the incidence of this problem as low as possible. A blood sample is needed for this test. This test is for CEA only, so CERF examinations must still be performed to rule out other types of hereditary eye disease such as progressive retinal atrophy. For an excellent discussion on the topic, see the following link www.optigen.com/opt9_test_cea_ch.html .
Frequencies Based on CERF Eye Exams in the U.S. from 1991 to 1999
|
Choroidal Hypoplasia |
Coloboma |
Retinal Detachment |
Collies |
66.7% |
8.75% |
1.88% |
Border Collies |
2.12% |
0.57% |
0.06% |
Shelties |
0.39% |
0.79% |
0.05% |
CERF numbers may underestimate the prevalence of the CEA mutation, because of the difficulty of detecting the defect in older dogs and the difficulty in diagnosing in a merled dog. Although the incidence of CEA in American Shelties is relatively low, it occurs in European Shetland Sheepdogs in a significantly greater frequency. For this reason, it is recommended that, at the very least, imported Shelties be tested for the CEA gene. Dogs “Clear By Parentage” (first generation - see OFA website for detailed policy) would be accepted into the CHIC program.
As of July, 2008, OptiGen will send the CEA (Collie eye anomaly) DNA test results for Shelties automatically to OFA. Only normal results will be made public unless an owner notifies OFA that he/she would like abnormal results to be posted. The normal OFA fee of $15 to have the results posted will discounted to $7.50 and collected by OptiGen. For more information see: http://www.optigen.com/
Elbow dysplasia – Of breeds having 100 or more elbow evaluations, Shetland Sheepdogs rank 62nd of 92 breeds with elbow dysplasia. As of March, 2008 there have been 404 Shelties evaluated with 97.3% being normal. More information about elbow dysplasia can be found at the following link: http://www.offa.org/elbowinfo.html . Radiographs (x-rays) are required for this test.
Congenital Cardiac Database – Many congenital cardiac defects have a genetic component, and nearly all common ones produce audible murmurs that can be detected by a veterinarian using a stethoscope. Although not common in Shelties, such defects have been found in the breed. OFA certification for the cardiac database is primarily based on examination by a veterinarian using a stethoscope. Because some veterinarians are more experienced at detecting subtle murmurs than other veterinarians, the ASSA Research Advisory Committee stipulated that the examination must be performed by a board certified veterinary cardiologist or internal medicine specialist. Dogs must be 12 mos. of age to receive a certification number. As of March, 2008 61 Sheltie evaluations have been entered into the OFA database. More information can be obtained at the following link: http://www.offa.org/cardiacinfo.html
American Temperament Testing Society, TT title - The “TT” title isn’t exactly a health test; however, some breeds do include temperament testing in their CHIC test list, and since heredity does play a role in temperament, the ASSA Research Advisory Committee included it on the optional list. Minimum age for a dog to take the test is 18 mos. As of December, 2007, 472 Shelties have been tested. The pass rate was 67.4%. More information on the test can be obtained at the following link: http://www.atts.org/about.html
1. George A. Padgett, DVM, Michigan State University, Prioritizing Genetic Defects, www.lgd.org/library/PadgettDefects.htm
2. Canine inherited disorders database - http://www.upei.ca/~cidd/intro.htm
3. From the OptiGen website: http://www.optigen.com/opt9_test_cea_ch.html
CHIC Program - Questions & Answers
May, 2008
1) For those dogs already meeting the requirements, how long do you think it will take before they show up on the site when one does a search for CHIC Shelties? Within two weeks.
2) Will dogs that have had CERF examinations be included if the exams are out of date? Yes, as long as there is a CERF report on file
3) Once a dog receives a CHIC number, he/she will remain on the CHIC list even if the CERF exam is out of date. Is that correct? Yes, both the CHIC report and website will list WHEN the test was done, as well as the cumulative CERF testing history
4) When submitting the results of the VetGen and MDR-1 tests, one should use the DNA application form (www.offa.org/dnainfo.html). On that form, there is a space for a previous application number. What is that referring to? Would the application number on the OFA certificate be it? Application number is the internal OFA assigned number
5) Is there a Clear by Parentage option available for both the vWD and the MDR-1 gene? The answer is yes. I believe that point is noted on the CHIC webpage for Shelties and on the ASSA website. Concerning the Clear by Parentage issue, I was unable to find any information on the VetGen website concerning the Clear by Parentage option. It may be there, I just didn't find it. I do know that the option is discussed on the OFA website http://offa.org/dnacbp.html . The following is from that page:"For direct mutant gene tests only, the OFA will issue clearances to untested offspring, if the sire and dam have both been DNA tested ?clear,? if the sire and dam?s DNA disease test results have been OFA registered, and if all three (sire/dam/offspring) have been DNA identity profiled and parentage verified. The DNA profile paperwork must be submitted along with a completed OFA DNA-based disease test application."
6) I had assumed that if the parents' results were registered by the OFA that the offspring would automatically be given the CBP clearance if the owner submitted the appropriate form and fee, but after reading the above, I see that there are additional requirements that, I think, will cause many owners to balk. Why not just accept that AKC registration papers are correct rather than requiring DNA profiles of all 3 individuals? For the MDR-1 test, it would be cheaper to get the test done on the offspring than to get the CBP done. Please let me know if I am understanding the situation correctly. The OFA Board discussed the CBP policy at the spring 2008 board meeting, and decided the policy should stand. The rationale is that the OFA is going out on a limb and issuing the clearance to an untested dog. In doing so, the board wants absolute confidence that the dog is in fact the offspring of the cleared parents. DNA profiling should not be viewed as a cost of the clearance, but a regular cost of breeding dogs. Responsible breeders should be profiling their dogs regardless for the integrity of the stud book.
7) Must a dog be permanently identified (tattoo or microchip) in order to have genetic test results posted on the OFA or CHIC website? On the OFA submission form, there is a place on the form for a veterinarian to certify that the DNA sample was correctly collected and that he/she had verified the permanent identification of the dog tested. If this is not done, you can still submit the test results. The inofmation may be listed as "no permanent identification" as is done for hip reports. If a veterinarian does not sign the OFA DNA form that goes with vWD and MDR-1 test results, there is another form, "Verification of Permanent Identification" http://offa.org/apps.html . It is suggested that you download and read that form to understand why it may be required in some instances.
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The Shetland Sheepdog Health Survey
September 2008
The Shetland Sheepdog health survey is available through the generosity of the Orthopedic Foundation for Animals(OFA), www.offa.org, and is the result of a collaborative effort between the OFA and the ASSA Research Advisory Committee. It became active October, 2008 and the data seen in the results section is cumulative since that time. Anyone owning a Sheltie may participate in the survey, and it it hoped that many owners will do so. Owners may input information for as many dogs as he/she wishes including information on normal and abnormal dogs, dogs already deceased and, of course, those still alive. If information changes for a dog already in the system, just re-enter that dog with the new information. Eventually, the numbers of dogs in the system will be so great that additional information on a dog already in the system will not make a significant difference in the overall percentages. This will not be a scientifically accurate survey, but it should give us a general idea of which health problems are more common and will guide us in selecting research projects for future support.
The first time you try to enter a dog into the Health Survey, consider clicking on all of the disease categories for the question: "Has your dog been diagnosed with any of the following health issues?", so you can see all of the options. A problem might be located in a different section than where you thought it might be. For instance, the MDR-1 genetic mutation is listed under "Neurologic disorders" since many of the adverse reactions associated with that trait cause neurological symptoms. If you dog doesn't have any problems in a given section, just leave that section blank. After you become familiar with the options, you can just click on the appropriate disease categories when entering additional dogs.
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CHIC DNA Repository
The CHIC DNA Repository is co-sponsored by the OFA and the AKC/Canine Health Foundation. Its purpose is to collect and store canine DNA samples along with pedigree and phenotypic information to facilitate future research and testing with the goal of reducing the incidence of inherited disease in dogs. The ASSA Board of Directors encourages participation in this DNA bank. For more information, visit: http://www.caninehealthinfo.org/dnabank.html.
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Current Research Projects
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Research on Canine Cancer
April, 2010
(For this work is supported by the AKC Canine Health Foundation. See: http://www.akcchf.org/research/participation.cfm)
Cancer researchers need samples
********************************************
The Van Andel Research Institute, a world class human cancer research institute, recently received a Federally fund grant through the National
Institutes of Health/National Cancer Institute, to study five types of cancer that occur in both dogs and humans. The ultimate goal is to develop
improved diagnostics and more individualized therapies for both canines and people.
We are requesting the help of purebred dog owners, who may own a dog affected with one of these cancers. The five initial cancers we are studying
are:
1) Hemangiosarcoma
2) Lymphoma
3) Osteosarcoma
4) Malignant histiocytosis
5) Melanoma of the mouth or toe
We are requesting fresh (NOT in formalin, NOT frozen) tissue samples from tumors, when pets have biopsies, surgeries such as splenectomies, or are
euthanized. Samples may be collected post mortem, as the euthanasia solution does not affect the DNA in either the dog's blood or in the tumor
cells.
Additionally, if you have a dog with one of these cancers who has already been treated (splenectomy, chemo, etc), we would still appreciate a blood
sample along with a histopath report confirming the diagnosis. We need 3-5 mls of whole blood in an EDTA (purple top) tube. It can be sent priority
mail, and blood can be shipped at room temperature.
If the pet is scheduled for surgery or, sadly, euthanasia, if you or your veterinarian contact us ahead of time, we can FedEx a collection kit which
includes an overnight FedEx return shipping form, along with collection media and containers.
Owner consent forms and veterinary info pages can be found on our website, at: http://www.vai.org/helpingdogs or http://www.vai.org/Research/Labs/CancerAndDevelopmentalCellBiology/chcc.aspx
I will be happy to answer any questions I can, as well. Owners, veterinarians and researchers working together will help us to unravel some
of the mysteries of these nasty diseases.
Roe Froman, DVM
Senior Veterinary Research Scientist
Van Andel Research Institute
333 Bostwick Ave NE
Grand Rapids, MI 49503
616.234.5556
roe.froman@...
www.vai.org
Investigations into the Genetic Mutations Causing Two Different Dental Anomalies in Shelties
You can download the articles and pictures in their entirty by clicking on the title under "Current Research Projects" at the top of this site.
“Lance” Canine Teeth and Abnormal 3rd Incisor Teeth
January, 2010
Dr. Gary S. Johnson of the Animal Molecular Genetic Laboratory, Department of Pathobiology, the College of Veterinary Medicine, The University of Missouri, has graciously agreed to search for genetic mutations underlying two different dental anomalies that occur in Shelties. Dr. Johnson’s research group has been the recipient of several AKC Health Foundation research grants, and this group is actively working on identifying the underlying genetic causes of various conditions in several breeds. One of the recent breakthroughs was identification of a genetic mutation responsible for degenerative myelopathy, a progressive condition causing irreversible paralysis, in Welsh Corgis, German Shepherd Dogs, and other breeds. Their work has resulted in DNA tests that can be used by breeders.
The two dental conditions (“lance” canine teeth, and abnormal upper 3rd incisor teeth) are described below. Participation of Sheltie breeders and owners are essential to the success of these studies.
Investigation of Rostrally Displaced, “Lance”, Canine Teeth in Shetland Sheepdogs
Description of the anomaly written by Mary Mahaffey, DVM, Chair, ASSA Research Advisory Committee
Background: A rostrally displaced maxillary (upper) canine tooth is one in which the adult canine tooth is displaced forward toward the nose (rostrally) so that it comes in contact with the 3rd incisor tooth, and it is located in front of the mandibular (lower) canine tooth rather than behind as is should (Figs. 1 & 2). The long axis of an affected tooth is more parallel to the hard palate rather than nearly perpendicular as for a normal canine tooth. In some dogs, the lance canine tooth can be so horizontal that the tip rubs on the upper lip. The deciduous (baby) canine teeth of affected dogs are normally positioned; however, the abnormal position of a lance canine tooth becomes evident as the adult tooth erupts. Because an affected tooth points forward like a lance or spear, it is commonly called a lance canine tooth.
The abnormal position of a lance canine tooth may prevent the mouth from closing completely, and may force the lower canine tooth to point outward causing the tip to rub the inside of the upper lip potentially causing ulceration. Also, food and tartar tend to accumulate between the lance canine tooth and the adjacent incisor tooth increasing the likelihood of periodontal disease between the two teeth. Although treatment is not required in all affected dogs, therapy is necessary in some. Treatment alternatives include extraction or crown shortening of the affected canine tooth and orthodontic repositioning which can cost several thousand dollars.
The condition is more commonly seen in Shetland Sheepdogs than other breeds and is considered to be heritable, so affected dogs should not be bred. The goal of this study is to identify gene(s) causing lance canine teeth and to develop a DNA test that can be used to identify adult carriers and affected puppies before the adult teeth erupt.
Fig. 1A Fig. 1B
 
Fig. 1A&B. Photos of the left (A) and right (B) sides of the mouth of a 4-year-old Shetland Sheepdog with a lance left canine tooth. The left upper canine tooth is displaced forward so that it is in front of the lower canine tooth and its tip touches the upper 3rd incisor tooth. Compare to the normally positioned right upper canine tooth in which the lower canine tooth is in front of the upper one. The right upper 2nd premolar tooth is absent. Periodontal disease between the lance canine tooth and the adjacent incisor tooth was avoided by daily tooth brushing.
Fig. 2: A young Sheltie with a lance left upper canine tooth that is in the process of erupting. The forward position of the abnormal tooth is more severe than that of the dog in Figure 1. The abnormal position of this tooth was so extreme that orthodontic repositioning was not a treatment option. The tooth was removed surgically and bone grafting was necessary to close the communication between the nasal cavity and the space occupied by the tooth root.
What is needed for this study:
- Blood samples from two groups of dogs -
- Shetland Sheepdogs with lance canine teeth (either one or both canine teeth affected)
- Close relatives (siblings, sire, or dam) of one of the above dogs with normally positioned canine teeth.
- The goal is to obtain blood samples from at least 25 dogs in each group.
- Pedigree of the above dogs or copy of the registration certificate.
- If possible, either hard copy or digital photographs of the right and left sides of the upper canine teeth.
- Completed Individual Dog Information & Survey Form (see below link).
All genetic and contact information collected for each dog will remain confidential. Specifically, your participation in the study, your dog’s pedigree, health information you provide, and any data obtained from your dog’s DNA sample will not be disclosed to any breeders, ASSA Club personnel, or to the AKC.
Thank you in advance for your time and effort. The sample you provide will be instrumental in helping to identify the genomic mutations associated with lance canine teeth. It is hoped that this study will lead to a genetic test for lance canine teeth that can be used by breeders to decrease the incidence of the problem in Shelties and identify affected dogs at a very early age. The work would not be possible without your participation and dedication to this wonderful breed.
Click on this link for information on sample submission and the Individual Dog Information & Survey Form.
Please contact Liz Hansen, Laboratory Coordinator, by phone (573-884-3712) or e-mail (HansenL@missouri.edu) with any questions or concerns you may have.
Investigation of Abnormal Upper 3rd Incisor Teeth in Shetland Sheepdogs
Description of the anomaly written by Mary Mahaffey, DVM, Chair, ASSA Research Advisory Committee
Background: Over the years, Sheltie breeders have occasionally observed Shelties in which one or both of the upper 3rd incisor (I-3) teeth in adult dogs are different in size, shape, and position than normal adult I-3 teeth.1 (The I-3 teeth are the incisor teeth adjacent to the canine teeth).
In affected Sheltie puppies, only 4 - to 5 upper incisor teeth are present at 4 wks rather than the normal number of 6. The central 4 incisors are present, but one or both I-3 teeth may be absent (Fig. 1 A&B). Around 12 – 16 wks of age, abnormal I-3 teeth erupt in most affected dogs; however, these teeth are larger than normal deciduous teeth, but smaller than normal adult incisor teeth. When erupted, the abnormal I-3 teeth may point outwardly and some may be rotated 90 degrees, as shown in Figs 2 B&C, 3C, & 4. The abnormal I-3 teeth may be retained indefinitely or may be shed months or years later. If shed within a few weeks of eruption, normal adult I-3 teeth may replace the abnormal ones; however, in older dogs, normal adult incisor teeth never appear.
Owners and judges may not recognize the presence of these abnormal I-3 teeth since they are similar to, but slightly smaller in size than, the central four incisor teeth. However, there are distinct differences in the appearance of the abnormal and normal adult I-3 teeth.
Normal adult upper I-3 teeth (Fig 3A):
- The distal tips point down and backward toward the tips of the upper canine teeth.
- They are larger than the other maxillary incisor teeth.
- The caudal margins (surfaces that normally face the adjacent canine teeth) are smooth.
Abnormal upper I-3 teeth:
- The distal tips point outwardly (Fig 2 C) and somewhat forward (not toward the canine teeth).
- They are similar in size or slightly smaller than the other adult maxillary incisor teeth, but they are larger than normal deciduous (baby) I-3 teeth.
- The caudal surfaces are notched (Fig 1B).
Thus, the abnormal I-3 teeth have features of deciduous teeth, but they are larger than normal deciduous teeth and rarely followed by normal adult teeth. I am aware of one Sheltie in which an adult tooth erupted within the hard palate behind the abnormal I-3 tooth.
What is known about the inheritance of this trait is that affected dogs and normal appearing dogs (with an affected parent) when bred to normal ones (that probably don’t carry the trait), both normal and abnormal pups are produced. Unless one is knowledgeable about whether or not this trait is present in the relatives of a normal dog, one cannot tell by phenotype if the dog is a carrier.
Why bother trying to develop a DNA test for this trait? The good news is that the condition, in most dogs, is cosmetic, rarely requiring surgical correction or interfering with function of the dog like other conditions such as hip dysplasia. However, the teeth are definitely abnormal and the trait has not been reported in other breeds to my knowledge. Empirically, the number of affected dogs in the show population is increasing as are reports of Shelties with missing incisors (only 4 adult central incisors with no deciduous I-3 precursors ever appearing), and dogs with missing 2nd upper incisor teeth. Perhaps, breeding 2 carriers or affected individuals would result in a greater number of missing incisor teeth. If breeders are unaware of the condition and the number of affected dogs continues to increase, the condition could become so prevalent that it would be impossible to eliminate or to keep it at a low prevalence. Superior individuals carrying the trait may well be desirable for a breeding program, and a DNA test for this anomaly would give breeders a mechanism for identifying normal appearing carriers, thereby allowing them to use that information in breeding decisions.
Fig. 1 A – Six week old Sheltie pup with missing right upper 3rd incisor tooth.
Fig. 1B – above Same pup as in Fig. 1A.
Fig. 2: A – top, B – middle, and C –above of the upper incisor teeth of a 15 wk old Sheltie. Arrows point to the 3rd incisor teeth. A – normal 3rd incisor tooth. B – abnormal 3rd incisor tooth that is rotated. Its tip is directed forward. C – The tip of the abnormal left 3rd incisor tooth (arrow) is pointed more outward than that of the normal right 3rd incisor tooth. The left upper I-3 tooth was missing at 6 wks of age and the abnormal tooth started to erupt at 12 wks of age.
Fig. 3A - C: 10 mo old Sheltie with an abnormal left upper 3rd incisor (I-3) tooth. Same dog as in Fig. 2.
(3A) – The right upper I-3 tooth (arrow) is normal. Notice that the I-3 tooth is larger than the central incisor teeth, the caudal margin is smooth, and the tip points slightly backward toward the tip of the upper canine tooth.
(3B) – The left upper I-3 tooth is abnormal. The tooth is smaller than the other incisor teeth, and there is a notch (arrow) in the caudal margin. In this dog, the tip of the I-3 tooth points slightly backward; however, in many affected dogs, the tip is directed more forward than seen in normal I-3 teeth.
(3C) - View of the front of the incisor teeth. Notice that the left I-3 tooth (black arrow) is smaller than the right and its tip is pointed more outward than that of the right I-3 tooth (white arrow). Incidentally, several of the lower incisor teeth extend more forward than normal.
Fig 4 –Sheltie with an abnormal upper left 3rd incisor tooth (I-3) that is smaller than the other incisors (I-1, I-2) and abnormally positioned so that the tip points outwardly. The upper right 3rd incisor tooth is absent. (canine = canine tooth).
1 Curry, Barbara A: Missing and crooked teeth. Sheltie International 13: 90, 1994.
What is needed for this study:
- Blood samples from two groups of dogs -
- Shetland Sheepdogs with abnormal upper I-3 teeth as described above (either one or both I-3 teeth affected)
- Close relatives (siblings, sire, or dam) of one of the above dogs with normal upper I-3 teeth.
- The goal is to obtain blood samples from at least 25 dogs in each group.
- Pedigree of the above dogs or copy of the registration certificate.
- If possible, either hard copy or digital photographs of the right and left sides of the upper incisor teeth.
- Completed Individual Dog Information & Survey Form (see below link).
All genetic and contact information collected for each dog will remain confidential. Specifically, your participation in the study, your dog’s pedigree, health information you provide, and any data obtained from your dog’s DNA sample will not be disclosed to any breeders, ASSA Club personnel, or to the AKC.
Thank you in advance for your time and effort. The sample you provide will be instrumental in helping to identify the genomic mutations associated with abnormal upper I-3 teeth. It is hoped that this study will lead to a genetic test that would give breeders a mechanism for identifying carriers and allow them to make informed breeding decisions regarding this trait. The work would not be possible without your participation and dedication to this wonderful breed.
Click on this link for information on sample submission and the Individual Dog Information & Survey Form.
Please contact Liz Hansen, Laboratory Coordinator, by phone (573-884-3712) or e-mail- HansenL@missouri.edu with any questions or concerns you may have.
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Dermatomyositis (DM)
Description of the condition:
“DM (dermatomyositis) is a devastating genetic disease of the skin and muscle, which afflicts Shetland Sheepdogs, Collies and their crosses. The skin lesions consist of hair loss with or without skin redness, scaling and crusting of the face, ears, legs/feet and tail tip. One or more of these areas of the body may be affected. In addition, some dogs may have muscular involvement. …. Shetland Sheepdogs are fortunate because the muscle involvement is relatively rare. Stress, such as that associated with the hormone fluctuations of heat cycle, will make the symptoms of DM worsen. Intact females appear to be more subject to hormone related stresses than intact males. Stress of travel, moving or family upsets may also make symptoms worse. The only way to diagnose DM is with a biopsy.” Sherry Lindsey, RN BSN, www.shalaine.com/DM/DM.html
Dermatomyositis (DM) Research - A Search for Potential Genetic Cause
February, 2010 Update
Dr. Christine Rees, Dr. Leigh Anne Clark, and Dr. Keith Murphy have done much of the research investigation concerning DM at Texas A & M University. The ASSA, through the ASSA Foundation, has made generous donations toward their research. The Collie Health Foundation has also been a major supporter of their work. Dr. Rees is now in private practice in Texas. Drs. Clark and Murphy are now working at Clemson University, Clemson, SC. The research has resulted in at least 2 scientific publications.1, 2 The current research on DM is now being done in Dr. Clark’s laboratory.
Research has shown that DM is not an autosomal recessive trait. It is a complex disorder which will require many more DNA samples from affected and normal dogs than would be needed if the condition were an autosomal recessive one.
Dr. Clark is working with the Collie Health Foundation and plans to scan the entire collie genome for genetic variants that may be associated with DM. She believes that the genetic bases of DM in Collies will likely be similar to those in Shelties. She is able and willing to underwrite the cost of processing blood samples from normal and affected Shelties and store the DNA for future DM research.
To generate additional data for Sheltie DM research using the canine SNP array, the Dr. Clark has requested blood samples from 2 groups of Shelties:
-
Blood samples from DM affected Shelties, along with a copy of the biopsy report confirming the diagnosis), include AKC registration number (if available).
-
Unaffected Shelties – 10 years or older, must have no history of focal hair loss or any skin condition, not related to a known DM dog, include AKC registration number (if available).
“Our goal is to collect 36 affected and 36 normal Shelties in the next year. I will cover the costs of isolating and storing the DNA. The owners will have to cover any veterinary fees and shipping costs. Most vets will collect the blood at no charge if they understand that it is for research.
We need a minimum of 3mls of whole blood in a purple-top tube. The blood should be shipped with cooler packs, preferably 2nd day. Samples should not be shipped when they will arrive over a weekend or a holiday. They can be stored in a regular refrigerator until they can be shipped.” The owner's name, pet's name, DM status and collection date should be clearly labeled on the tube. Please include owner contact information (email) in case Dr. Clark has any questions.
Mail to:
Dr. Leigh Anne Clark
Clemson University
51 New Cherry Rd
319 BRC bldg
Clemson, SC 29634-0318
Phone: 864-656-4696
Email: lclark4@clemson.edu
Please support this important research by submitting blood samples and through monetary donations. Those owners with older unaffected Shelties should be able to help reach the goal of samples from 36 dogs.
Donations to the ASSA Foundation to fund DM research would be greatly appreciated. The cost of evaluating DNA samples is approximately $400 – 500/dog. For more information on the ASSA foundation, go to: http://assa.org/foundation.html .
1 Wahl JM, Clark LA, Skalli O, Ambrus A, Rees CA, Mansell JL, Murphy KE: Analysis of gene transcript profiling and immunobiology in Shetland sheepdogs with dermatomyositis. Vet Dermatol. 2008, 19(2):52-8. www.ncbi.nlm.nih.gov/pubmed/18336421
2 Clark LA, Credille KM, Murphy KE, Rees CA: Brief communication, Linkage of dermatomyositis in the Shetland Sheepdog to chromosome 35. Vet Dermatol. 2005, 16:392-394. http://www3.interscience.wiley.com/journal/118705211/abstract
Dermatomyositis Research - New Treatment Study
Updated, February, 2010
While at Texas A & M University, Dr. Christine Rees investigated the use of Dapsone as an alternative treatment to Trental (pentoxifylline) for dogs with DM. Dapsone is an oral medication found to be effective in the treatment of DM in humans. The following is a report from Sherry Lindsey RN BSN on the results of the study. Sherry has worked closely with the researchers at Texas A & M and has maintained an extensive website on DM in Shelties.
“The best treatment option for DM symptoms continues to be Trental or pentoxifylline. It is recommended that brand name be used rather than generic. The dose used in the study is 25 to 30 milligrams per kilogram of body weight every 12 hours given by mouth and always with food. These tablets have been successfully split when used in treating the DM study dogs.
Dapsone was also studied and could be used as an alternative in those rare dogs who do not tolerate Trental. The Dapsone dose in the study was 1 milligram per kilogram of body weight every eight hours, given by mouth. However, several dogs did well after being on the Dapsone for a month or two at 1 milligram per kilogram of body weight every 12 hours, by mouth.”
Contacts for DM information/questions:
Sherry Lindsey RN BSN is a longtime Sheltie breeder who assisted Dr. Rees in all of the DM studies and housed and cared for the DM study dogs. She is happy to answer any questions concerning DM and may be reached at shalainetx@aol.com. A website with DM information, including photos of DM affected dogs, may be found at www.shalaine.com/DM/DM.html
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Leishmaniasis Research
July 2008
Participants needed to trap insects that might be able to carry Leishmaniasis. Basically, Dr. Mendez is asking dog owners to hang insect traps around the home or kennel area for 24-48 hrs and then mail them back to her at her expense. I urge each of you to participate especially since it seems to be an easy thing to do. Just contact her via e-mail (Dr. Susana Mendez, sm457@cornell.edu) telling her that you are interested in participating. Also, please forward this message to all of your "doggie friends" and ask them to participate and forward on to their friends. Letter from Dr. Mendez
Leishmaniasis Information
Best regards,
Mary Mahaffey, DVM Chair,
ASSA Research Advisory Committee
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Investigation of Bladder Cancer in the Shetland Sheepdog
Updated March, 2010
Background: The Ostrander Laboratory at the National Human Genome Research Institute at NIH in collaboration with the Purdue Comparative Oncology Program at Purdue University and the Department of Small Animal Clinical Sciences at Michigan State University have been working since 2006 to discover the genetic causes of transitional cell carcinoma (TCC) of the urinary bladder in dogs. TCC is a devastating disease and Shetland Sheepdogs are four and one half times more likely to be diagnosed with TCC than most other dogs. Our ultimate goal is to identify the genetic variants responsible for this much increased susceptibility to the disease.
We are excited to be able to report the completion of our first SNP based genome-wide analysis in more than 60 of our best Sheltie cases and controls. The most informative cases have a diagnosis of TCC confirmed by biopsy with histopathology. The best controls have passed the age of eight with no diagnosis of cancer of any kind.
Our researchers looked for locations in the genome that differ between affected and unaffected dogs, and have found genomic region(s) that appear to be important in TCC. We believe that further testing can lead to identification of causative mutations responsible for development and progression of TCC of the urinary bladder in Shetland Sheepdogs, as well as in other dog breeds* that are at high risk of developing the disease.
Our thanks go out to the American Shetland Sheepdog Association and all Shetland Sheepdog owners for their great response to our request for blood samples for our TCC research. Because of your support we have received samples from 57 Shelties with TCC and 68 healthy, control Shelties at least 8 years of age.
In order to complete our goals, we are in need of more samples, especially from the two groups listed above; dogs with complete biopsy confirmed diagnosis of TCC and healthy, aged controls. In addition, we ask that you please keep us updated as to the health of your participating dogs so that we can keep them in the correct study group. If your dog just celebrated his/her eighth birthday in good health, let us know. If your dog has received a diagnosis of cancer since he/she submitted a sample, please fax or mail the veterinarian’s report to us at the address below. Updates can be sent to us either by phone, email, or through our online survey at http://research.nhgri.nih.gov/dog_genome/, which can be accessed with the password: Missy07.
If you would like to participate in the TCC study and you need information or a sampling kit, please contact:
Donna Viglietti
Ostrander Lab Samples Manager
Phone: 301-451-9390Fax: 301-594-0023
Email: dog_genome@mail.nih.gov
National Institutes of Health / NHGRI50
South Drive, Bldg. 50, Room 5347
Bethesda, MD 20892-8000
Each kit contains a one page consent form, a pair of vials for collecting 5-10 cc of blood at your veterinarian’s office, and instructions for handling the blood. The collection kit comes in a small cardboard mailer tube that protects the blood vials. A return address label is included so that the forms and blood can be sent back to the lab conveniently. Blood can be mailed at room temperature without cold packs.
As always, your participation in the study and any information you provide us will remain confidential. Specifically, your participation in the study, your dog’s pedigree, health information you provide, and any data we get from your dog’s DNA sample will not be disclosed to any breeders, Club personnel, the AKC, or the AKC Canine Health Foundation.
This has been an exciting year for TCC research and we feel very optimistic about the direction that the research is taking. None of this would have been possible without your dedication to this wonderful breed and its health. We hope our work will determine the genetic cause of TCC so that steps can be taken toward the prevention of this terrible disease. With your continued participation and enthusiasm, we are making great strides in that direction.
*The Scottish Terrier and West Highland White Terrier are at greater risk than Shelties.
To see the original letter on the March 2010 update click here.
To see the original letter on the August 2009 update click here.
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Undescended Testicles (Cryptorchidism) Research
November, 2008, Updated May, 2009
There are 2 research groups studying the problem of cryptorchidism (retained testicles) in Shelties. Both research projects are sponsored by the Canine Health Foundation and the ASSA. Although both studies concern the same topic, the investigators are using different approaches to study the problem. Breeders are urged to contribute to both studies if possible.
Dr. Agoulnik, of the Department of Human and Molecular Genetics, College of Medicine, Florida International University (previously at Baylor Medical School), is using a “global” approach to find genes associated with cryptorchidism by looking at larger strands of DNA to find an association with the trait and further pinpointing the genes from there. Because he needs a large quantity of good quality DNA for his work, he must use blood samples or testicular tissue rather than DNA collected using cheek brushes. (Canine Health Foundation Grant No. 882-A)
Dr. Rothschild, a geneticist at Iowa State University, (Canine Health Foundation Grant No. 1018-A) has been studying cryptorchidism in species other than dogs. He is looking to see if the genes that cause the problem in man, pigs, and mice also are associated with the problem in dogs. The fact that DNA from cheek brush samples can be used for this study makes it easy for owners to collect the DNA samples themselves.
Both studies are described below:
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Undescended Testicles (Cryptorchidism) Research
Canine Health Foundation Grant No. 882-A
Cryptorchidism or retained testicles is the most common birth defect in purebred dogs. Two major health consequences of cryptorchidism are infertility at adulthood and significantly increased risk of testicular cancer. Because of the cancer risk, the retained testicles should be removed. Currently, there is no genetic diagnostic test to predict the risk of this disease in a dog’s progeny. The main objective of this study is to develop a DNA test that may predict the risk of a dog to produce cryptorchidism in its male offspring. Blood samples or tissues samples (testicles) removed during surgery from cryptorchid dogs and their normal littermates are needed for the current DNA research sponsored by AKC CHF. The information generated by this study can be used to identify animals with the mutant gene and thus will provide breeders with informative breeding recommendations.
Samples are needed from cryptorchid Shelties and their normal male littermates. (Samples from normal male littermates are not required, but would be helpful.)
Material needed for participation:
- 2-6 cc of whole blood in purple topped EDTA tubes or
- Frozen testicular tissue removed during castration
- AKC registration number and/or pedigree
- Consent form (obtained from Dr. Agoulnik)
This should all be sent over night with a cold pack to:
Alexander I. Agoulnik, Ph.D.
Professor
Department of Human and Molecular Genetics,
College of Medicine
Florida International University
11200 SW 8th Street, HLS I 327
Miami, Florida 33199
Telephone: (305) 348-1483
E-mail: aagoulni@fiu.edu
Prior to collecting the samples, please notify Dr Agoulnik to request the consent form and shipping instructions. If you explain the purpose of the blood draw, most veterinarians will draw the blood sample at no charge or for a reduced amount. The study will pay for shipping costs.
We sincerely thank everybody who helps with our research aimed to benefit all dog breeders.
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Comparative Gene Discovery for Canine Cryptorchidism
Canine Health Foundation Grant No. 1018-A
Dr. Rothschild, the primary investigator, is a geneticist at Iowa State University. He has been studying cryptorchidism in species other than canine. He is looking to see if the genes that cause the problem in man, pigs, and mice also are associated with the problem in dogs. He is currently working with Siberian Huskies but is banking DNA from other breeds.
After being contacted by the ASSA Research Advisory Committee, he agreed to include Shelties in his study. He would be greatly appreciative and could put the samples to good use. Because obtaining sufficient samples from the right sets of dogs (see below) has been a slow, time consuming process with the Siberian Huskies, he asked that one of the ASSA representatives collect the samples and then send them to him once the needed numbers have been obtained. Mary Mahaffey, DVM is willing to take the lead on this. This is what is needed for the study:
- Cheek brush DNA samples from 20 groups of the following: sire, dam, at least one normal male pup and one cryptorchid pup. (Grandparents would be good also if obtainable).
- Pedigree of the puppies.
The fact that cheek brush samples rather than blood samples are used in this study makes it easier to obtain the samples as owners can collect the DNA themselves. Obtaining 20 combinations as described above may not be easy, but can be done. DNA collected on cheek brushes can be kept indefinitely as long as the brushes are dry and kept in paper envelops. Once 20 of the above combinations are obtained, all will be sent to Dr. Rothschild at the same time.
If the owners wish to keep the information confidential, put all the materials for each litter in a large envelope and indicate on the outside of the envelope that DNA samples of the sire, dam, affected and unaffected male offspring are included inside (without listing the dog names). Then put that envelope inside a larger one and mail it to Mary Mahaffey, DVM at the address below.
To participate in the study, contact Mary Mahaffey and she will send you DNA collection kits and instructions.
Mary Mahaffey, DVM
1611 Cedar Road
Watkinsville, GA 30677
E-mail address: lastly3345@bellsouth.net
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Investigation of Gallbladder Disease and Hypercholesterolemia in Shetland Sheepdogs*
March 2008, Updated December, 2008, May 2009, November 2009
NEWS FLASH!!! Genetic Mutation Found!
Dr. Katrina Mealey, primary investigator of the study, reported to the ASSA Research Advisory Committee in September, 2009 that her group has identified a genetic mutation in Shelties that is strongly associated with gallbladder mucoceles. It is important that the data be reviewed by scientists and veterinarians prior to offering a test for the mutation to Sheltie owners. The work will be submitted for publication soon. Once the work has been validated, a DNA test should be made available. Dr. Mealey’s group is the same one that developed the DNA test for the MDR-1 gene.
Dr. Mealey said, “We sincerely appreciate the cooperation we have received from the American Shetland Sheepdog Association and we will keep you apprised of developments.” Sheltie owners and the ASSA played an important role in providing Dr. Mealey with the material needed to identify the mutation. It was only 18 months from the time the ASSA became involved in distributing information about the study in March of 2008 until the discovery of the mutation was announced in September, 2009! A special thank you to everyone who participated!
Study Background: Gallbladder disease has been recognized with increasing frequency in dogs since the late 1990’s1-3. Whether or not this was the result of a true increase in disease prevalence or simply the result of increased detection is unclear. Some have suggested that incorporation of abdominal ultrasound examination in dogs as a routine diagnostic tool has resulted in increased detection of gallbladder disease2. Several articles describing gallbladder mucoceles (severe distention of the gallbladder caused by a thick mass of sludge and mucus) in dogs suggest a breed predilection for the problem in Shetland Sheepdogs as well as Cocker Spaniels and Miniature Schnauzers. Both Shetland Sheepdogs and Miniature Schnauzers are breeds predisposed to hyperlipidemia (too much lipid or fat in the blood), 4, 5 a factor that is known to contribute to gallbladder disease in people6, 7. A study has confirmed a link between hyperlipidemia and hypercholesterolemia (high blood cholesterol levels) and gallbladder mucocele formation in Shetland Sheepdogs2. Collectively, this suggested the possibility of a genetic defect in a protein responsible for lipid homeostasis (regulation of blood lipid levels). In March, 2008, The Veterinary Clinical Pharmacology Laboratory, led by Dr. Katrina Mealey, at Washington State University began a research study investigating a gene that plays an important role in lipid homeostasis. It was proposed that a defect in that gene could be the underlying cause of gallbladder disease in Shetland Sheepdogs.
The ASSA assisted Dr. Mealey in collection of DNA samples from Shelties with and without hyperlipidemia and gallbladder disease by sending notice of the study through Sheltie related internet message groups and posting the information on the ASSA web page. Nine months after the study began, enough material was obtained, through the generous participation of Sheltie owners, to limit sample collection to dogs with surgically confirmed gallbladder mucoceles and older normal Shelties. As noted above, it was a mere 18 months from the beginning of ASSA participation until the genetic mutation was confirmed. This could not have been accomplished without the enthusiastic participation of Sheltie owners, and of course, without the dedication and expertise of Dr. Mealey
Dr. Mealey said, “I was surprised (in a positive way) on the response!…Thanks for your assistance--for an uncommon disease we were able to collect a good number of samples with complete medical information in a short time period (especially considering this was breed specific!)”. Thanks to everyone who has participated.
THANK YOU Dr. Mealey!!!
Katrina Mealey DVM PhD; Diplomate, ACVIM; Diplomate, ACVCP
Associate Professor and Director, Veterinary Clinical Pharmacology Laboratory
College of Veterinary Medicine
Washington State University
Pullman WA, 99164-6610
EMAIL: kmealey@vetmed.wsu.edu
http://www.vetmed.wsu.edu/depts-VCPL/instructions.aspx
References
Pike FS, Bert J, King NW, et al. Gallbladder mucoceles in dogs: 30 cases (2000-2002). J Am Vet Med Assoc 2004;224:1615-1622.
Aguirre AL, Center SA, Randolph JF, et al. Gallbladder disease in Shetland Sheepdogs: 38 cases (1995-2005). J Am Vet Med Assoc 2007;231:79-88.
Worley DR, Hottinger HA, Lawrency HJ. Surgical management of gallbladder mucoceles in dogs: 22 cases (1999-2003). J Am Vet Med Assoc 2004;225:1418-1422.
Whitney MS, Boon GD, Rebar AH, et al. Ultracentrifugal and electrophoretic characteristics of the plasma lipoproteins of miniature schnauzer dogs with idiopathic hyperlipoproteinemia. J Vet Intern Med 1993; 7:253-260.
Sato K, Agoh H, Kaneshige T, et al. Hypercholesterolemia in Shetland sheepdogs. J Vet Med Sci 2000; 62:1297-1301.
Loria P, Leonardo A, Lombardini S, et al. Gallstone disease in non-alcoholic fatty liver: prevalence and associated risk factors. J Gastroenterol Hepatol 2005; 20:1176-1184.
Andreotti G, Chen J, Gao YT, et al. Serum lipid levels and the risk of biliary tract cancers and biliary stones: A population-based study in China. Int J Cancer (2007 epub)
* This report will be updated when the study is published and when the DNA test becomes commercially available.
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Articles
To Test or Not to Test…
Mary E. Galloway DVM
May, 2008
As ASSA Health chairperson*, people who want to purchase a Sheltie frequently contact me asking what they should know about the breed’s health problems. A recent call highlighted some concerns expressed by both breeders and owners about the current focus on canine health and research and how it reflects on the perceived health of purebred dogs and Shelties in particular.
"I am interested in buying a Sheltie but when I hear about all the tests my puppy’s parents should have it worries me. I see your club is involved in various health research projects and is trying to raise money for further research. Should I look for a healthier breed? When I spoke with one breeder I was told about all the tests her dogs have had for a lot of diseases. I can get a Sheltie from another person who told me they don’t have to test for problems since they don’t have any in their lines. What do you think?"
Testing for diseases and monitoring the occurrence of diseases by breed clubs and breeders does not indicate that problems exist in that breed or line. In fact it is a positive indication that the people who breed these dogs are trying to produce the healthiest puppies they can. As researchers become more aware of the underlying causes for many diseases in our dogs, breeders try to use all the resources available to them to produce healthy dogs. This includes feeding a proper diet, providing proper exercise and housing and may include testing for abnormal conditions or diseases that exist in the breed. Testing for specific conditions will allow only unaffected animals to be used for breeding. The abnormal conditions currently recognized in Shelties are found in low numbers in the breed. Testing will allow these uncommon conditions to remain uncommon or even be eliminated from the breed.
A test may be one that screens for the presence of a condition or disease. This would include eye exams (CERF), radiographs of the hips for hip dysplasia (OFA, PennHip) or a blood test for thyroid disease. When a dog has one of these tests done it will tell the owner whether the condition is present in that dog at that time. Many of these tests need to be repeated throughout the dog’s lifetime since the condition can develop as the animal matures and ages. Some tests are done just once at a predetermined age since it is unlikely the condition will develop after that time. Checking for these conditions will allow breeders to breed only dogs that appear normal. What must be remembered is that although the dog may not show the condition him/herself these tests do not show if the dog is genetically free of the problem. The dog may appear normal but carry recessive genes. When this dog is bred to another dog also carrying recessive genes they may produce animals that will develop the disease. This is how affected animals can come from "normal" parents. The best safeguard we have to reduce or eliminate these problems in our dogs is to screen all breeding stock and breed only from those who are free of the condition. In the case of eye checks and thyroid testing, it must be repeated many times in a dog’s lifetime since these abnormalities may not appear until an animal is older. If all animals in the first 3-4 generations of your puppy’s pedigree have been tested and found normal it is unlikely that your puppy will develop the condition. It is important to point out that many of the disease conditions we recognize as having a genetic basis can also be influenced by the environment. The development of hip dysplasia is a good example. Research has shown diet and exercise as well as growth rates, can influence the development of hip dysplasia. Obesity can cause or aggravate a number of disease conditions in dogs. It is the owner’s responsibility to know how to correctly feed, house and exercise their growing puppy to ensure a healthy adult and to maintain good health in your adult dog.
The only absolute way to know your puppy will not develop a certain disease or condition is through genetic testing. A genetic test allows us to know what is actually coded in the genes of the animal being bred. It is not influenced by environment or outside stresses. It will tell you what genes the dog actually carries and not just which ones are expressed. Research is unlocking the key to many diseases in dogs and people. As these tests are developed and become available, breeders will test their breeding stock and know the genetic makeup of each animal. This will allow breedings to be planned to avoid producing affected offspring and to eventually eliminate the disease from the breed. The only genetic based test currently available for the Shetland Sheepdog is for von Willebrand’s Disease, a bleeding disorder. (As of 2008, additional DNA tests have become available. See the CHIC section above.)
That is why all this research is so important. Projects are underway to study many of the conditions that affect our Shelties today. Funding is needed for other projects that are of equal importance. As we eliminate one disease from our animals there will be others to demand our attention. That is why parent clubs like the ASSA monitor the breed through health surveys. Living creatures including dogs and man are constantly changing. Gene mutations are an ongoing process. Some mutations will produce disease conditions not recognized today. It is said all people carry 5-6 lethal genes as well as numerous genes that can cause the development of many disease conditions. The same is probably true for our dogs. The challenge for breeders is to use all the knowledge available today to avoid breeding animals together that carry the same deleterious genes. There is no dog or line of dogs that is free of all disease causing genes. If testing is not done, breeders may not be aware of problems that exist, but they are still there. It is true some diseases can’t be tested for at this time. They can be unpredictable and the best we can do is not use for breeding animals that develop the condition.
So don’t be afraid of a breed or breeder that is active in health research and testing of their breeding animals. This indicates the acceptance of responsibility and an ongoing effort to produce beautiful healthy Shelties.
* Although Dr. Galloway is not the current Chair of the ASSA Research Advisory Committee (formerly known as the Health Committee), the information in this well-written article is still appropriate and helpful.
Copyright © 1998-2008 American Shetland Sheepdog Association. All Rights Reserved.
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