You may have heard stories in your high school science classes about kings and queens that used to keep their bloodlines pure by marrying within the family. After years and years of this practice, a child would be born with tons of physical and mental problems. Your teacher probably explained that this was because all of the “bad” genes finally showed up through the inbreeding. Whether this story is true or whether it is merely an illustration, it demonstrates a valid point, along with a little exaggeration. Genetics is a complicated science, so this will be put as simply as possible.

It is easier to understand the problems of breeding if you can identify the different methods of breeding. Inbreeding, as demonstrated with the kings and queens, is the process of breeding inside the family. That is, the male and female are related, even if only cousins. Linebreeding is a form of inbreeding that is used to achieve “hard to find” traits, such as a recessive color. Linebreeding takes a son or daughter and breeds it with the female. Crossbreeding is a practice where dogs are mixed breeds. Proponents of crossbreeding claim that the dogs are much healthier than inbred dogs. Almost everything about the dog is either inherited or developed through the environment. Eye color, coat color, size, and temperament are passed down through breeding. Temperament, though, can also be affected by the environment that the puppy is brought into.

Even the best breeders can run into problems. Depending upon the size of the operation, there are more than likely a small handful of males and females that are used to breed. Sometimes, even, there are only two dogs that continuously breed. You may be wondering why a breeder would not pull two dogs from completely different blood lines. This can, and does, happen; but the difficulty arises when the breeder is trying to reach a desired trait. It is highly unlikely that dogs from two different bloodlines carry the same trait. This is when linebreeding takes place. If a breeder is trying to produce puppies of a recessive color, then he will use linebreeding to accomplish his task. However, when breeding you cannot choose which genes will be passed down, and the bad are passed along with the good (the same is true with inbreeding). Eventually, a genetic disorder arises because, to put it simply, the bad genes have built up and affected the bloodline.

Another similar problem occurs when one dog is used to breed multiple litters. For example, people may want a direct descendent of a dog that has won all sorts of competitions and awards. Why not breed him? He’s almost perfect, right? Well, in reality, he is still carrying not so good genes are veiled by the better genes. You can bet, however, that he will pass down both types.

A good breeder will not use dogs that have known genetic defects to breed more puppies. This is why many breeders will guarantee the health of their pups. However, a backyard breeder that is uneducated in the matter will continue to produce unhealthy dogs, especially since many of the disorders do not show up until later in life. Hip dysplasia, eye problems, and heart problems are all genetic disorders that have made their way into the bloodlines of breeds. Not only is this adding to the pet overpopulation (where many end up being euthanized), but it is adding unhealthy animals to the problem.

Breeding is a science that involves the help and knowledge of many people. Thankfully, breeders do not have to tackle the tasks on their own. There are organizations that help supply breeders information on certain diseases or genetic defects and the findings of recent studies concerning the two. Keeping an open line of communication between breeders also helps in the breeding process.

There are many problems that can result from improper breeding, and this merely touched the tip of the iceberg. Even though it is not easy to understand the hows and whys of gene selection and inheritance, it is beneficial to understand the complications of breeding. Even the best of breeders may run into problems that are simply out of their control (remember that environment can play a pretty big role). Open communication is growing in popularity and helping breeders breed healthy pets.

Source by Brian Spilner