Endocrine Disorders

Alaskan Malamute Research Foundation, Inc., English Setter Association of America, Golden Retriever Foundation, Keeshond Club of America, Orthopedic Foundation for Animals, Samoyed Club of America Education & Research Foundation, Siberian Husky Club of America Trust

Rebecca L. Davies, PhD

Alaskan Malamute, English Setter, Golden Retriever, Keeshond, Samoyed, Siberian Husky

The thyroid gland secretes hormones which are very important for development, growth, reproduction and metabolism. Sometimes the thyroid gland does not produce enough thyroid hormone and hypothyroidism occurs. Hypothyroidism is very common in dogs and many are treated with thyroid hormone supplementation. This disease occurs frequently in Alaskan Malamutes, English Setters, Golden Retrievers, Keeshonden, Samoyeds, and Siberian Huskies. Hypothyroidism is generally diagnosed by measuring the concentration of thyroid hormones in serum. This concentration is then compared to a reference interval derived from measurements of thyroid hormone concentration in samples taken from large groups of normal dogs. Generally this works very well, however, in some breeds, the true reference range is lower than the range determined when dogs of various breeds (or mixed-breeds) are analyzed. Breed-specific thyroid hormone reference intervals have only been determined in a few breeds. Without breed-specific intervals, inappropriate use of general values may result in healthy dogs being misclassified as hypothyroid. These animals may be incorrectly placed on thyroid supplementation, and unnecessarily removed from breeding programs. Furthermore, the incidence of hypothyroidism in the breed will be overestimated. We wish to establish breed-specific normal thyroid reference intervals to improve the diagnosis of true hypothyroidism in the Alaskan Malamute, English Setter, Golden Retriever, Keeshond, Samoyed, and Siberian Husky breeds.

Eye Disease

Siberian Husky Club of America

Cathryn Mellersh

Alaskan Malamute, American Eskimo Dog, Norwegian Buhund, Norwegian Elkhound, Schipperke, Siberian Husky

Hereditary cataracts (HC) are a leading cause of blindness in dogs and thus represent a significant health and welfare burden to many breeds of dog. The work outlined in this proposal aims to identify the genetic cause of HC in Northern breeds, a closely related group of breeds that collectively suffer a high incidence of HC. A successful outcome of the project will enable us to develop diagnostic DNA tests that breeders can use to determine whether their dogs are affected with HC and whether they will pass the condition onto their offspring. DNA tests enable carrier and even affected dogs to be safely bred from, if they are good examples of their breed and they are only mated to dogs that have tested clear of HC, thus keeping their valuable genes in the population without risking the production of affected offspring.

Eye Disease

Alaskan Malamute Club of America, Inc., Alaskan Malamute Research Foundation, Inc., Samoyed Club of America Education & Research Foundation, Siberian Husky Club of America

Vilma Yuzbasiyan-Gurkan, PhD

Alaskan Malamute, Samoyed, Siberian Husky

To better understand the mode of inheritance of canine cataracts, researchers collected extensive DNA, pedigree and clinical information from breeders and owners of Alaskan Malamutes, Siberian Huskies and Samoyeds. The data point to autosomal recessive inheritance, indicating that affected dogs must receive a gene from each parent. To try to find the genetic marker for the disease, researchers did a genome-wide linkage analysis with microsatellite markers in each breed. This work has eliminated large portions of the genome for harboring the causative gene and honed in on a region for the Samoyed cataracts. Further work should lead to identification of markers for each breed. While different types of cataracts can exist in a breed, there are some breeds where specific cataracts occur and appear to be inherited. Alaskan Malamutes, Siberian Huskies and Samoyeds have characteristic cataracts that are observed in young dogs.

Sports Medicine

Not Listed

Erica McKenzie, BSc, BVMS, PhD, DACVIM

Alaskan Malamute, Siberian Husky

Clinical Relevance: Diarrhea is extremely common in sled dogs during racing. Clostridium perfringens and Clostridium difficile are bacteria that produce different types of toxins that are significantly associated with diarrhea in pet dogs. Growing concern that these bacteria are responsible for `race diarrhea¿ in sled dogs has led to potentially inappropriate antibiotic treatment of sled dogs, and the production of a homemade Clostridium vaccine, of which the efficacy and potential risks are unknown. Determining if Clostridium spp. are associated with `race diarrhea¿ will allow establishment of appropriate and safe treatment and prevention protocols for racing dogs. Objectives: To determine if C. pefringens and C. difficile and their toxins are associated with diarrhea in racing sled dogs, and to determine if other species of bacteria potentiate the likelihood of diarrhea occurring when toxins are present. Experimental approach: Fresh feces will be collected from 50 sled dogs prior to the 2008 Iditarod Race and from 50 diarrheic and 50 non-diarrheic dogs during the race. Feces will be analyzed for toxins and tested for other bacteria (Campylobacter and Salmonella). Associations between the presence of toxin(s) and diarrhea, and between toxin(s) and other co-factors including Campylobacter or Salmonella spp. and diarrhea will be examined.