FACTORS INFLUENCING THE SPEED AND APPEARANCE OF HORSES OF THE ORLOV’S TROTTER OF UKRAINIAN SELECTION

The research is devoted to determining the factors that influence the speed and exterior of horses of the Orlov’s trotting breed of the Ukrainian population. It is proved that stallions and mares have weak and low strength negative relationships between the indicators of speed with linear measurements of the trunk, which confirms the expediency of their consideration when conducting parallel breeding for these features in the direction of preserving the original exterior and expressive harness type, rather than achieving maximum speed. Using the general linear model, the influence of genetic factors (linear affiliation, linear combination of father and mother, prize performance (speed per 1600 m) of proband ancestors of two rows of pedigree and the number of ancestors of the speed class 2.10 min in three rows of pedigree) and paratypical factors (Year and month of Birth, Gender, Year of testing, Stud Farm, Racetrack, Trainer) was determined. A significant influence of linear affiliation and linear combination of parent pairs on the speed of horses of the Orlov’s trotting breed (32.1 %), as well as the class of speed of ancestors of the first two rows of the pedigree (17.4%) was established. A positive low correlation was established between the prize performance of stallions and their offspring of 2-year-old age at the level of r=0.183 (p<0.05), 3-year-old age r=0.280 (p<0.05). The closest relationship was found between the speed indicators of stallions and their offspring aged 4 years and older (r=0.550, p<0.05), which can be explained by more careful selection of the best speed offspring of stallions for tests at an older age. Maternal influence on the vivacity indicators of offspring is manifested to a very significant positive degree (r=0.340) at the age of offspring four years and older. With positive force, this relationship affects only the speed of their older sons (r=0.397) and 4-year-old daughters (r=0.362). The mother’s speed class correlates quite significantly with negative strength with the vivacity of offspring aged 5 years and older. Such paratypical factors as the trainer (training systems) (225.3 %), the gender of the horses (75.6 %), the racetrack (74.8 %) and the stud farm (69.9%) showed the most significant influence on the conscription performance of horses of the Orlov’s trotting breed. An indicator of the coefficient of determination (R2) approaching 50% indicates that the speed indicator of the studied horses is determined by the applied model.