91色情片

91色情片: We must breed happier, healthier dogs

The health problems suffered by pedigree dogs have caused outrage. Veterinary scientist Paul McGreevy looks at how dog breeding should reinvent itself

SO INTERDEPENDENT are humans and dogs, that we may even have co-evolved. Yet we seem to struggle to maintain their quality of life. Last month, for example, argued that winners of dog shows are selected chiefly on appearance and movement, at the expense of their health and well-being.

Since it was screened, leading animal welfare charities such as the Dogs Trust and the RSPCA have spoken out against pedigree dog breeding, and , the UK Kennel Club鈥檚 flagship event. It is time for a new approach to dog breeding: one based on a comprehensive understanding of their biology; which values their health, longevity and suitable temperament; and ensures we get the best out of companion dogs by helping them to help us.

Many veterinary geneticists predicted the crisis that now faces the Kennel Club decades ago. Pedigree breeders use a closed studbook system, in which only descendants from an initial population of animals can be bred, but this inevitably increases the risk of . Such disorders are now recognised in all established breeds of dogs and cats, as well as horses, farm animals and captive exotic species. But the problem is worst in dogs, which have been intensively bred within the closed studbook system since Victorian times. Many dogs now have inherited disorders that inflict so much suffering it is unkind to keep them alive.

To make matters worse, pedigree dog breeders compete to produce animals that conform to written standards, which may include traits that inadvertently compromise quality of life. These traits were included in the first breed standards set when dogs left the working arena and entered the world of dog shows in the late 1800s. Many of them were valued by early dog domesticators because they served a purpose, such as long legs for hunting dogs, or muscular build for guard dogs. Unfortunately, breeders now tend to prioritise looks over function, and to pursue traits with excessive zeal.

The , for example, demands that the chest is 鈥渨ell developed, deep鈥 while the abdomen is 鈥渇irmly held鈥 and the flank 鈥渕oderately tucked-up鈥. These traits help to make the dogs appear athletic but puts them at risk of gastric dilation and torsion, an agonising, lifethreatening condition in which the stomach bloats with gas and can become twisted. Or take , which is required to have eyes that are 鈥渧ery large, globular in shape鈥. Breeders select for this, leaving pugs with eyes that bulge so badly their lids can scarcely meet well enough to wipe the eyeball clean. The poor dogs suffer a lifetime of chronic conjunctivitis that scars the cornea and blinds them.

The emphasis in dog breeding needs to shift. To minimise rates of inherited disease, studbooks should be opened to other dogs. There are also calls for each breeding population of pedigree dogs to be placed under surveillance, to track new disorders as they emerge.

We should also celebrate the traits we truly value in dogs. In most societies these days, dogs are chiefly companions. So temperament is important 鈥 鈥渋nappropriate鈥 behaviour is the commonest reason for dogs in developed countries to be euthanised. Dogs that bond appropriately with people and cope well with the pressures of living in high-density urban environments are likely to have a higher quality of life, as well as serving their owners better. Yet the selection process in the show ring barely reflects temperament 鈥 the only behaviour test the show dog has to pass is not biting the judge. It is good to see a pilot scheme to promote behavioural traits appropriate for modern domestic environments under way in Australia, with the blessing of the national dog breeding body.

鈥淭he only behaviour test the show dog has to pass is not biting the judge鈥

Ultimately, the relationship between dogs and humans is changing. Encouraging high-quality bonds is seen as more important than getting dogs into many homes. In the past, veterinarians have had to rely on crude measures of well-being such as longevity and 鈥渂ehavioural wastage鈥 鈥 the proportion of dogs abandoned, surrendered or euthanised because of their behaviour. But they can now also use more sophisticated tools, such as the Quality of Life matrices used by doctors. Perhaps one day breeders will compete in a class for 鈥淭he dog with the best chance for a high quality of life鈥.

It is fascinating to speculate how dogs and humans might co-evolve further. We cannot say exactly what the domestic dogs of the future will look like because we do not know what future humans will need and therefore value. But pedigree dogs, as they are currently defined, are doomed. Inherited disorders will only become more and more common unless the breeding rules are changed.

The best dog breeders have the passion to bring about the necessary transformation. They are very good at what they do 鈥 the problem is that what they currently do is not very good. Welfare charities, veterinary associations and breeders must unite in using the latest advances in genetics and epidemiology to find a new model of dog-breeding practice.

Genetics 鈥 Keep up with the pace in our continually updated special report.

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