Can dogs inbreeding?

In Australia, about 65,438+0/3 purebred dogs suffer from various diseases due to genetic defects, ranging from mild umbilical hernia to severe blindness and brain diseases. German wolfhound (the most common dog breed in Australia) is more prone to hip joint disease than golden retriever; 70% Rottweilers (second only to German dogs in popularity) also suffer from the same disease. In addition, 70% of sheepdogs suffer from eye diseases caused by genetic problems, of which 65,438+00% are blind, while Damamachi and Bainiutou are often deaf.

Ian Docrates, a surgical veterinarian, said, "During my working hours, half of the people are undergoing spinal surgery. Those sick dogs include dachshunds, Lhasa dogs and Beijing dogs. Recently, bull terrier in England was euthanized because of rabbit lips; Rabbit lips are a common defect in this kind of dog.

Cases like this keep happening. Great Danes and Newfoundland dogs often have congenital heart diseases, and Sha Pigou often has congenital skin diseases. Besides, some dogs are not only mentally ill, but also mentally ill. RobertHolmes, a veterinarian and dog psychologist, said: "Some cocker spaniel will be stressed and urinate frequently; Irish hounds are usually considered stupid. They can't even find the end of the rope tied to them. 」

More than 300 diseases caused by gene defects have brought great pain to sick dogs, and their owners have also been affected emotionally, not to mention the expensive treatment costs. Moreover, this phenomenon is getting more and more serious. HughWirth, the chairman of RSPCA (Royal Society for the Prevention of Cruelty to Animals) in Australia and an animal surgeon with 32 years' experience, said: "Some purebred dogs, such as poodles and CavalierKingCharles hounds, have mysterious genetic defects, so they should stop trading unless they are screened by geneticists. 」

In order to pursue the so-called purebred, breeders let dogs inbreeding at will.

First, gene abuse against natural selection.

Genetic defects can be life-threatening. Every species has some genetic diseases. In nature, unsuitable creatures will be eliminated naturally, but not in the breeding of dog breeds. Genetic diseases do not happen by accident. Among the 1.69 dog breeds recognized by Ankc100000 members, many breeds are bred only for beauty and convenience for participating in competitions or dog shows. Breeders usually adopt inbreeding in order to meet the appearance standards and maintain pure blood, which leads to the health problems of dogs.

About 5500 years ago, in the Bronze Age, the ancestors of dogs began to perform different tasks for human beings and carry out selective cultivation. Shepherd dogs are raised for herding sheep; Mastiff used for defense; Greyhound hunt antelopes. According to the ancient records of China. In 3400 BC, Emperor Fu Yi specially bred a miniature dog to warm his hands in winter. Pompeii, which was destroyed by the eruption of Mount Vesuvius in 79 AD, has many doors engraved with "CAVECANEM", which means beware of evil dogs.

Generally speaking. In the past, people chose healthy and lively dogs to perform specific tasks. For example, golden retrievers are used to hunt with hunters, and lame dogs will not be kept. However, in the past 50 years, the most common ways to keep dogs and inbreeding are just to look good. What kind of "appearance standard" should a variety meet? This standard is formulated by some kennel associations, such as FCI.

"The appearance has been divorced from the function. These bred breeds no longer retain the nature of dogs, and bulldogs and Beijing dogs can't even survive in the wild. BillPorges, a senior lecturer who teaches small animal medicine at the University of Sydney, said. Only paying attention to the beauty of appearance may encourage unhealthy animals to breed, which is "survival of the fittest". Dr. Worth, chairman of RSPCA, also said: "In a limited gene pool, breeding so-called purebred dogs requires hard-hearted screening, but no one has done so. At present, dogs have faced a worldwide health crisis, and only a few breeds can escape this robbery.

Inbreeding is more likely to cause genetic diseases.

Second, appearance standards will only bring trouble.

Researchers have limited knowledge about diseases caused by genetic defects. Among hundreds of genetic diseases, only 32 can be detected by genetic tests. Biologists know much more about fruit flies, because there are less than 65,438+000 dog geneticists in the world, and they only work in a few universities, so they often need to raise research funds.

"Insufficient research funds" sounds very wrong! Dogs are the most common pets in Australian families. About 38% families have dogs, and only 365,438+0% families have cats. According to the market survey made by the pet food industry, dog-related products account for half of the 2 billion pet commodity market every year. Then, "who is responsible for the suffering dog?" Is this the kennel association? Did FCI set the dog's appearance standard? Is it a breeder? Or consumers who want to buy purebred dogs? For breeders and dog races, it's hard to turn back. Looking back at1862165438+10, when the first competition was held in Hobart, Australia, some standards were unhealthy, requiring that the upper eyelids of basset dogs, police dogs and St. Bernard dogs droop, causing various eye discomfort. Cocoa must have soft ears, which make people look forward to love, but the ears are often infected; German wolfhounds must bow their hind legs and tilt their hips. When standing, their gait looks streamlined, which often leads to dislocation of their hips.

What will dogs look like when they become popular? "Once, cows and dogs had to have a concave back like an oak saddle, but now people think their backs should be hard and straight. In the past, they had to have bigger heads, like bears. We must abolish these absurd standards, otherwise no one will care whether animals are healthy or not. BereniceWalters, who has been raising sheepdogs since 195 1, said.

From a biological point of view, "appearance standard" will only bring trouble. In Victorian times, English bulldogs were bred for bullfighting. A century of inbreeding deliberately cultivated broad shoulders and strong forehead, but due to genetic problems, it was impossible to walk. A so-called typical English bulldog may cost thousands of Australian dollars in medical expenses. They often suffer from respiratory and heart diseases, as well as skin diseases and eye diseases, all of which are caused by genetic defects. Facts have proved that cows and dogs in Britain can't give birth naturally at all. Because their heads are too big and their shoulders are too wide, they can't squeeze into the bitch's birth canal at all.

"Master should be able to do more! DoreenRees, an Irish hound breeder, said, "Too many people buy dogs just for fashion, regardless of whether they can take care of them. I heard an old joke that Irish hounds were too stupid to find the other end of the leash. To tell the truth, Irish hounds are not stupid, but they need moderate exercise and enough space, otherwise they will become stupid because they are too bored. Nutrition, the environment, and even the wet floor can make them injured or sick. These are not just genetic problems.

Most owners don't know whether their dogs have potential genetic diseases, and once they get sick, the cure rate is quite low.

Three. Annual1300 million USD medical expenses

Of course, not all purebred dogs have genetic problems, and dogs raised for work rarely have this disease. Dogulas said, "Greyhound rarely dislocates its hip joint, because they have to run very fast. Dogs with defective hip joints are usually euthanized at an early age. So do other working dogs.

Another positive example is that the Knight Charles Hound Club in the United States overwhelmingly opposed the standards set by AKC for dogs on the grounds that "AKC cares about their value far more than their welfare. In the United States, the National People's Congress invests a lot of money every year, and the competition is fierce. Only to meet the standards set by the authoritative AKC, about1300 million yuan is spent on dealing with dog health problems every year.

In some European countries, such as Sweden, some dog breeds with abnormal appearance, such as Sha Pigou with wrinkled skin, are not allowed to be registered, because they are deformed to the point that they are no longer what they should be.

"Breeders don't want to filter unhealthy dogs. Dr. Worth said: "Some people sell puppies as pet dogs because they are valuable. Some people think that elimination is a way to lose money, so they will continue to breed without a pedigree certificate. It is not that purebred dogs have more genetic problems than other dogs, but inbreeding, which increases the probability of genetic diseases. Most genetic diseases are caused by recessive genes. If a puppy can get good genes (or dominant genes) from one of its parents, it will not get sick, but if both parents come from the same family, the newborn puppy may have problems.

However, even if there are no potential genetic problems, genetic defects may occur. The biological interaction between genes is very complex, which may have unexpected consequences while strengthening some characteristics. Veterinarians believe that the genes that cause retinal problems in most sheepdogs are related to the characteristics that the breeder particularly emphasizes.

Fourth, we should start with gene control.

Responsible breeders will gradually eliminate dogs with genetic defects. ANKC has set up a committee on genetic diseases to investigate how to avoid genetic diseases, and use X-rays to check which dogs may pass on problematic genes to the next generation. For example, the German Wolfhound Club examined more than 5,000 German Wolfhounds with X-rays and recorded their family history. In addition, the breeders of sheepdogs also published a detailed list of known carriers of brain genetic defects. This kind of dog will become irritable after illness and die within two years.

The recent establishment of a new moral concept can be attributed to human respect for the environment in the 1990 s, which made consumers and breeders more aware of their responsibilities to animals and nature; At the same time, it may also be threatened by law.

Now breeders can use scientific methods to find the potential diseases of dogs, so as to avoid bad feeding decisions. The United States has developed the use of computers to establish basic files of genetic diseases. At present, there are more than 300 genetic problems in dogs. The other is PennHIP program (a detection system for hip diseases, which can carefully measure the severity of whitening of hip bones on X-rays). This software has been put on the market, launched by the international dog gene American company, and has been trained by veterinarians.

But the final answer still lies in the general breeders and owners. Everyone must have the knowledge of * * *-those 800 or so dog breeds whose appearance standards have been formulated by FCI are simply inappropriate versions. GeraldineHunt, a veterinary cardiologist at the University of Sydney, said: "If we don't start from the source-genes, there is no way to improve the problem. 」