Ralston Purina funds and supports canine genetic research independently and through the American Kennel Club Canine Health Foundation, and leads the effort to encourage collaboration among scientists worldwide. With a goal of helping breeders produce healthier dogs, Purina is committed to addressing the challenges of genetic disease through sound breeding programs, nutritional management and medical therapy.
Dog breeders have known for years that the critical determinants of a dog's longevity often relate to its development as a puppy, which is influenced partly by nutrition. Though a dog's genetic makeup and family history contribute to its geriatric performance, the impact of diet can be key in determining the expression of certain characteristics or conditions.
An adult dog has the same genetic makeup as when it was a puppy. As a dog ages, however, some genes may be "turned up" or "down" - up-regulated or down-regulated - in response to changes in the environment experienced repeatedly over time. By utilizing or instilling lifelong good nutrition and health practices, dog owners may be able to minimize or stave off some senior dog conditions such as arthritis, obesity and some types of cancer.
A dog's genetic makeup is unique. While one dog may thrive on a nutrient-dense diet, another dog could become overweight. Breeds that are genetically susceptible to obesity should be closely monitored through each life stage. Older dogs that gain too much weight should be fed diets for senior dogs, weight-reduction or maintenance.
Depending on an individual dog's phenotype, sometimes simply changing the molecular component of the diet can help correct a health problem, such as food allergy. Although food allergies are rare, those that occur commonly involve reactions to meat proteins. Feeding a diet with a modified protein, such as soy protein, may be less likely to cause an allergic response in those predisposed dogs.
Genetic research has led to the development of diagnostic tests for 15 of the more than 300 inherited canine diseases. Scientists are able to use deoxyribonucleic acid (DNA) material from an individual dog and determine whether that dog carries the gene responsible for conditions such as cystinuria or von Willebrand's disease.
Cystinuria, found in Newfoundlands, mastiffs, English bulldogs, chihuahuas, dachshunds and basset hounds, is a disease characterized by stones in the kidney, urethra and bladder. Canine von Willebrand's disease is a blood-clotting disorder that sometimes causes fatal bleeding. It occurs in breeds such as poodles, Manchester terriers, Pembroke Welsh corgis and Doberman pinschers.
For most inherited canine diseases, the underlying genetic cause is yet to be determined. Learning the causes of these diseases will require careful screening of the entire genome in pedigrees of dogs carrying the disease — particularly since many of these diseases are inherited from recessive genes.
Though many genetic diseases are not influenced by diet, breeders who can identify dogs that carry the gene for a particular disease can develop stronger breeding programs. As scientists learn more about the location of genes responsible for disease, the development of more specific diagnostic tests may become available. In addition, as new methods in molecular genetics become available, it is probable that a future generation of purebred dogs will be healthier and longer-lived than their predecessors.