Both ethically sound humans and most animals without ethics consider inbreeding taboo. Because inbreeding can make the incidence of some recessive gene infectious diseases higher. Although genes were not known in ancient times, through the observation of offspring from the marriage of close relatives, it was found that the probability of the marriage of close relatives leading to deformities and problems such as mental disability was greatly improved. The same goes for animals, many of which avoid having relationships with their close family.
There is a legend in folklore that in ancient China, in order to cultivate good horses, blindfolded ponies had sex with their blindfolded mothers. As a result, after discovering that the mating partners were his relatives, the horses both committed suicide. Plans to use horse inbreeding to produce good purebred horses were shelved.
But there is also a saying that this is the story Aristotle told his students. Of course, this story is likely to be fictional. Leaving aside the authenticity of this story, it reflects the objective fact that many animals avoid inbreeding.
In addition, inbreeding animals do not have a high survival rate due to disease. In order to maintain the continuation of the population, animals can avoid having relationships with their close relatives.
But dogs don't have the habit of deliberately avoiding inbreeding. When a female dog gives birth to a large group of puppies, the puppies of the dog group will have a relationship, and even the puppies will have a relationship with the large dogs. The reason for this is mainly the special living environment of pet dogs.
First, staying away from other similar species is an important inducement for pet dogs to breed inbreeding
Pet dogs are animals that are domesticated by humans. Because of the separation from their own population, in order to reproduce the group, they can only choose to breed with their own inbreeds. This is very similar to the situation of many sparsely populated tribes living on isolated islands. For the continuation of the tribe, inbreeding can only be chosen. This greatly increases the probability of the onset of recessive genetic diseases. After several generations of reproduction, the population has become more and more sparse.
Moreover, the dog's sexual desire is particularly strong, and the dog in estrus is very difficult to manage. As soon as the dog enters the estrus period, the sexual desire cannot be vented, and it will be abnormally irritable and irritable. Puppies in a group of dogs have sex with their mothers or sisters during estrus.
Deformed children produced by inbreeding
In order not to let the dogs in estrus cause damage to the family environment, and at the same time to reduce the huge economic burden caused by the unlimited reproduction of the dogs. Many families with dogs will choose to take their dogs for sterilization. The dog that has been sterilized is not only much more emotionally stable, but also does not like to move. Dog owners are also much better. The only problem is that dogs are particularly prone to obesity after sterilization, and dog owners should pay attention to the dog's health problems, strengthen moderate physical exercise and diet after that.
The picture shows the pet dog after castration, and the thing on the pet dog's head is an Elizabethan circle to prevent the pet dog from licking the wound after the castration and causing infection
Second, human selection is an important inducement for pet dogs to breed inbreeding
In the 19th century, there was a frenzied pursuit of thoroughbred dogs in Europe. Thoroughbred dogs are humans who keep a valuable dog breed in their proper shape by inbreeding some of the most valuable dog breeds. At the same time, a relevant pedigree monitoring agency was established to provide a certificate of pedigree testing for thoroughbred dogs. If you breed a dog of the same breed but come from a different region, the agency will not issue a certificate. Dogs also can't sell for a good price. Although the price of purebred dogs is several times more expensive than the price of ordinary dogs. But until now, there is still a frenzied pursuit of pure-blood dogs in the pet market.
Pure-blood Hilti Shepherd, a price of 3400-4200 yuan, is three times more expensive than the ordinary Hilti Shepherd
Since thoroughbred dogs are produced by inbreeding, the more thoroughbred dogs suffer from diseases in the next few generations, the healthier they become. The BBC Radio and Television Station in the United Kingdom has made a documentary about the tragic life of purebred dogs, called "The Sorrow of Purebred Dogs".
The documentary points out very sharply that it is the pathological love of certain special characteristics of human beings and the paranoid pursuit of pet pedigree that leads to the tragedy of pure-blood dogs. In addition, pet exhibits are also responsible for the tragic proliferation of thoroughbred dogs. For the sake of fame and money, many dog breeders pull pure-blood pet dogs with specific breeding traits to the exhibition.
Not only did Europeans fanatically pursue "pure blood" in keeping pets, but even in the aristocratic bloodline, they also demanded "pure blood". The most extreme of this was done by the Habsburgs, the rulers of the Austro-Hungarian Empire. In order to ensure the purity of the family lineage, members of the Habsburg family only intermarried internally. The consequence of this is that the members of the Habsburg family are becoming more stupid and shorter-lived from generation to generation. With the dissolution of the Austro-Hungarian Empire in 1918, the Habsburgs also declined.
An interesting point is that since the Habsburg royal family was the product of the marriage of close relatives, the members of the Habsburgs not only had low intelligence and short life expectancy, but also showed obvious characteristics in appearance. The trait was jokingly referred to as the "Habsburg chin" after the fall of the Habsburgs. Due to intermarriage and incest among close relatives, members of the Habsburg family became more and more similar in appearance and their traits became more prominent. By observing the paintings of the Habsburg family, it is not difficult to find that the jaws of the Habsburg family are particularly large, which is the proverbial "shoehorn face".
The "shoehorn face" maxilla is underdeveloped and formed a contraction, and the mandible is overdeveloped, resulting in a protrusion. The middle of the face is concave, and the side looks like a wheel moon. Its symptomatic scientific name is "anti-jaw", and it is commonly known as "earth bag heaven" or "pocket teeth" in China. That is, the shoehorn face is a physical deformity that needs to be corrected by surgery. From this point of view, the demise of the Habsburgs, who were married by close relatives, was predestined.
Third, reflections on the problem of dog inbreeding
Abandoning the fact that dogs are not exclusive to inbreeding by nature, it is really disgraceful for humans to use this for their own profiteering. The "doctrine of descent" had already embodied its extreme backwardness and ignorance in the Habsburgs, and the Habsburgs had paid a terrible price for their stupidity and short-sightedness. Pure-blood pets, on the other hand, can only silently endure the "biological experiments" that humans carry out on themselves in order to satisfy their vanity and endless greed.
Comparison of the original Bull Terrier with the Minotaur Terrier produced by artificial selection and inbreeding
In fact, there is no need to specifically breed purebred dogs for the sake of good looks. Using good dogs of the same breed of non-immediate relatives to improve genes not only can also obtain a good appearance, but also is not prone to family genetic diseases. "The Sorrow of a Purebred Dog" mentions the use of foreign dogs to cross with thoroughbred dogs to reduce the probability of family genetic diseases in offspring. The working principle is to use the English indicator dog to cross with the barley dog to produce a crossed dog with normal uric acid levels and the appearance of the barley dog.
Purebred Barley Machi Dog, the dog in Disney's anime 101 Loyal Dog is the Damai Machi Dog
In order to breed a barley dog with beautiful spots, the barley dog loses the ability to regulate uric acid during the process of purebred breeding. Eating and drinking in dogs will produce a large number of bladder stones in the bladder, which will endanger the safety of dogs if they are not removed in time. Many barley dogs have died of bladder rupture caused by bladder stones accumulating in the body.
Although dogs can breed in close inbred, humans have no right to interfere with the dog's behavior. Because dogs are animals, they cannot be measured by human morality. And humans can't take advantage of this flaw in dogs to make huge profits for themselves.