Selective breeding is when humans use plant or animal breeding to develop the characteristics in the organism that they find most suitable. By making these animals breed with each other until a “purebred” is achieved humans are attempting to give a breed desirable and stable traits to pass on to the next generation.
People have been selectively breeding dogs for a very long time. This has been practiced mostly to accommodate with human needs, such as hunting prey, guarding property, or herding livestock. Throughout the ages humans have managed to create more than three-hundred breeds of dogs that did not exist before.
However this process of selective breeding has not come without it’s consequences. Evolution is very good at making healthy breeds of a species, after all that is it’s entire purpose; to make a species more adaptable and suited towards it’s environment. Nature is very good at this, humans however, not so much. Purebred dogs are actually the most susceptible to getting chronic health problems.
A reoccurring theme in the conditions that breeds of dogs can be affected by is that they are “congenital” conditions, meaning they are directly the result of the dog’s genes.
Small Dog Breed Issues
Some dogs have been bred for purely aesthetic reasons. Take bulldogs for example, while bred by humans to be cute, their squished faces have created respiratory issues for them as a breed. Their small, short noses have created a shorter air passage to the lungs than in other breeds. This is known as Brachycephalic Airway Syndrome and is very common in small breeds like Pugs, Pomeranians, Shih Tzus, and Chihuahuas.
Small dogs of the toy and tea cup variety are known to suffer from heart problems at a much higher rate than that of large dogs. Their hearts beat at a much faster rate than that of larger dogs, up to 160 beats per minute, which causes a good amount of strain on such a little body.
Small dog breeds are at a risk of Patellar Luxation, known as a “floating kneecap,” which is when a dog’s kneecap becomes dislocated from it’s regular position. This condition usually becomes apparent in the dog’s atypical movement, and can seemingly occur out of the blue.
Another common affliction for the smaller breeds is pancreatitis, developed when the pancreas becomes inflamed. The pancreas is essential in producing enzymes that digest food and produce insulin. When affected this has many side-effects such as vomiting, diarrhea, and many others that are very uncomfortable for your dog.
Large Dog Breed Issues
Large selectively bred dogs are also not immune to the issues created by humans interfering with nature. Large dogs also have a plethora of problems to deal with, ranging from mild annoyances to serious issues.
Somewhere around one-fifth of all dogs are affected by atopic dermatitis, which is itchy, inflamed skin. While are dogs can be affected, Dalmatians and large Terrier breeds are the most susceptible. In extreme cases, this condition can lead to skin infections.
Some of the largest breeds of dogs such as Great Danes, Mastiffs, German Shepherds and Saint Bernards are much more likely than their smaller relatives to have orthopedic issues such as hip dysplasia, which is a congenital condition. The wearing on their hip joints is what leads a lot of these bigger dogs to develop arthritis in their later years. The wider the hips in a breed, the more likely they are to be affected.
These large breeds of large dogs are also known to be much more likely to be predisposed to cancer, which is heavily caused by genetics. Some of the most common that occur frequently with them are bone cancer and gastric cancer.
Selective breeding has even caused autoimmune problems in purebred dogs. This immune system is responsible in people and in animals to fight off foreign invaders of the body. Several autoimmune issues have been noted in these selectively bred dogs. Signs that your dog may be afflicted by one of these conditions include a loss of appetite, fever, and lethargy.
Some dogs, most notably Bassett Hounds, even have issues with blood disorders. This is a major issue, as it affects the blood’s ability to clot after an injury. This can lead to hemorrhaging and bruising. Clotting issues are especially serious with Dobermans, who are the most likely to be afflicted with Von Willebrand’s disease, yet another genetic condition caused by human breeding.
Neurological and Behavioral Issues
Neurological and behavioral issues are common in dogs, and affect many dogs of purebred breeds. Neurological disorders occur in your dog’s central nervous system. The areas where these problems affect dogs are the brain, spinal cord, and nerves. These types of disorders can come along with absolutely no warning signs. Symptoms can include but are not limited to, odd head tilt, seizures, shaking, hanging tongue, and blindness.
One type of neurological disorder frequently suffered by larger breeds is Vestibular Syndrome. Typically occurring in older dogs, it is when a dog loses his sense of balance. This condition can come about suddenly, and many dog owners jump to the conclusion that their dog has suffered a stroke. This is not the case, it is actually an issue with balance which is controlled by nerves in the inner ear. This condition can make your dog feel ill, as if the room is spinning, shifting eyes. Luckily this condition is treatable, and most dogs recover after a few weeks.
Another neurological issue to address in the largest breed of dogs is Wobbler Syndrome. It is a congenital disease that affects the vertebrae of the neck and back, causing compression in their spinal cord. This can be observed by your dog progressively walking more strangely. Treatment of this condition does require surgery, and many weeks of steroidal therapy.
The good news about neurological disorders in dogs is that they are largely manageable with medications and other treatments.
We bred all kinds of amazing breeds of dogs to meet all kinds of human standards, but it didn’t come without a price