Selection of sighthound dog breeds
During selective breeding, it is impossible to change any single trait without affecting other traits. This is primarily due to the fact that any organism (and a dog's organism is no exception) is an integrated system. It should be noted that absolutely all quantitative traits in dogs are polygenic. Consequently, hybridological analysis, which involves crossing and separating discrete traits in the second generation, is impossible.
The point is that in this case, no segregation occurs. However, it's important to remember that even minor changes introduced by a mutant gene into the polygenic system determining a trait result in a change in that trait. In other words, no segregation occurs. Based on all of the above, it follows that various mutations and the combination of existing gene complexes during crossbreeding are factors that determine the genetic diversity of breeds.
The selection tools are:
- Selection by behavior (in other words, selection is carried out based on working qualities and functionality);
- By appearance (in this case, we mean the exterior).
At the dawn of the last century, the plant breeder Konrad Lorenz formulated a postulate. According to this postulate, selection for the expression of body traits, carried out without any testing of the functionality of these traits, inevitably alters the behavior and properties of the entire organism.
During extensive research into the domestication of silver foxes, it was discovered that selection for behavior (in this case, the animal's attitude toward humans) causes changes in both morphological and physiological traits. Therefore, it can be considered established that the use of only one form of selection (selection for a single trait) causes changes not only in species but also, undoubtedly, in breeds.
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Dog breeding - selection process
It should be noted that dog breeding is, in any case, nothing more than selection, even against the wishes of the breeder. The fact is that people breed dogs that fully meet their needs and conditions and that are comfortable in life. However, when breeding dogs, most people have little understanding of what is needed to preserve breeds. Certainly, some breeders plan and develop strategies. But, unfortunately, quite often even the best breeders fail to realize their intentions. The poor results of selection are due to the fact that breeders, when making plans, focus on phenotypes, while genotypes are inherited.
The point is that the genome shouldn't be viewed as the sum of its genes. This means that a single gene can't be responsible for just one specific exterior trait. Therefore, a breeder who wants to change or maintain one trait inevitably faces the prospect of altering many other traits. Furthermore, it should be noted that even when a breeder doesn't select for traits, tries to avoid changes, and attempts to preserve existing traits, selection still occurs. In such cases, subtle traits act as selection patterns.
As an example, for a breeder to produce a flawless show dog, they must bring a puppy with potential and specific qualities to shows as early as possible. In this case, it's best to start with the puppy class. However, it's important to remember that early-developing dogs, which resemble adults of good lineage even before puberty, have an advantage in both puppy and junior classes.
The rate of development and the pace of ontogenesis in these dogs are controlled genetically. This suggests that, in this particular example, selection is aimed at supporting early developmental traits. In other words, the selection vector is aimed at ensuring that dogs develop rapidly, regardless of how typical this rapid development is for the breed as a whole.
To preserve a breed (whether chosen or simply beloved), the selection process must be consciously determined. Given that selection based on individual traits, as discussed above, is doomed to failure, the only way to preserve a breed is through comprehensive selection. A good example of comprehensive selection is the domestic hunting system of field trials for wild animals (hereinafter referred to as the "Rules").
These "Rules" are intended to regulate the description of greyhounds' pursuit of a free-moving hare. A fox may be used instead of (or in addition to) a hare. The description is regulated by a point-based evaluation of the dog's actions, whether performed (or not performed) during the pursuit. Some believe that the "Rules" can be used to compare the hunting qualities of dogs. However, this widespread belief is erroneous, as the "Rules" are intended solely to compare the breeding qualities of greyhounds.
Testing procedure
The testing procedure is described below:
Location and group division
Trials must be conducted in areas that meet certain characteristics. Specifically, the area must have large fields. Furthermore, the area must be populated by free-ranging animals, with a satisfactory population density. Hares (usually brown hares, less commonly white hares) are typically used as the test animals. However, red foxes can also be used instead. Trials are conducted throughout the autumn daylight hours, that is, from approximately 8:00 a.m. to 3:00 p.m. to 5:00 p.m. Dogs participating in the trials should be divided into groups (numbers), each containing two or three dogs.
Groups must move in a single file (line) at a distance of 15-30 meters across the testing area, following the expert's commands. The animal is then raised and pursued (chased) by one of the groups. The chase is scored in points according to a special table and described verbally. It should be noted that the chase will not be scored by the experts if its duration is less than 200 meters and if the starting distance is less than 25 meters.
Conditions of the "tests"
Furthermore, the expert evaluates the race based on its conditions. The fact is that race conditions can be easy, difficult, or prohibited, depending on the animal's behavior. Therefore, the conditions of the same race can be difficult, easy, or prohibited. Ultimately, everything depends on the course of the hunted animal.
Racing conditions are considered difficult if they involved weeds, forest plantations, tall stubble, and rough plowed land. Racing conditions are considered easy if they took place on soft ground, winter crops, hayfields, stubble, and fallow land.
Tests should not be conducted on coarse plowed soil, on soil that is soaked by rain, in foggy weather, if the temperature exceeds 15 degrees Celsius or falls below -10 degrees Celsius, if the snow cover is more than 15 cm deep, or in areas of icy conditions, frozen soil. Furthermore, testing is prohibited in fields from which crops such as corn, sunflowers, and alfalfa have been harvested. Tests should also not be conducted in gullies or ravines overgrown with reeds or moss.
Dog owners participating in the trials are not only prohibited from making noise but also from disturbing the route or the release rules in any way. Specifically, it is prohibited to launch the dog at a nearby animal (a nearby animal is considered to be within 25 meters of the animal), to chase a young or small animal, to launch the dog while another group (number) is currently participating in the trial, or to launch the dog at an animal that remains after another animal has been tested.
Dogs participating in the test are prohibited from displaying uncontrolled aggression toward people or other dogs in their group. Furthermore, dogs are prohibited from attacking pets, eating, or tearing animals apart. The above is a brief description of the test procedure, outlining the minimum requirements for a dog to be evaluated.
In particular, as a result of the tests the following description is performed:
- health - the ability to move for five to eight hours on different types of soil, regardless of precipitation (snow, rain) and sun, and then be able to pursue an animal;
- education and training, expressed in complete indifference to domestic animals;
- social behavior that is expressed in controlled aggression towards humans and other animals;
- hunting behavior, expressed in the presence of a pursuit reaction and the simultaneous absence of a food reaction to the victim of this pursuit.
To summarize, the Russian field trial system is aimed at verifying the presence of health, social, and hunting behavior traits, as well as training elements provided by the dog owner. It is undeniable that all of the above traits, as well as trainability, are controlled at the genetic level. Consequently, only a dog that possesses these characteristics and successfully completes the chase (test) can be awarded the appropriate diploma. According to statistics, no more than 30 percent of dogs can be nominated for such a diploma, which certifies "field" qualification.
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