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Abstract

The analysis of the effectiveness of various options of parental pairs selection was held from which the Orlov trotters were received of class 2.05 and faster for their assessment, depending on liveliness, precocity, age of parents, measurements and indices, according to the linear affiliation of parents and inbreeding.
As a result of research, it was found that the largest number of Oryol trotters of class 2.05 was obtained from stallions of class 2.05 and 2.08 (76.8 %) and from mares of class 2.15 and 2.20 (42.3 %). Although a fairly large number (16.9 %) of trotters were born from untested mares.
The best precocity in the Orlov trotters of class 2.05 (4.9 years) was found in the offspring of the Weter and Barchuk lines (32 heads, or 11.8 %) – 72 heads (26.5 %) showed their best agility at the age of 3-4 years.
The largest percentage in the age selection of parents: a mother older than her father is mainly 1-5 years old – 26.5 % (72 h), a father older than her mother also 1-5 years old – 38.6 % (105 h). The most effective were the selections, where the age of the stallions-producers was 6-13 years, mares 5-11 years (168 goals, 61.8 %). It should be noted that among stallions-producers and mares, the number of live offspring decreases after 15 years.
The largest among the parents were the stallions-producers – representatives of the Barchuk and Woin lines, and among the mares – Weter and Woin. The lowest among stallions and mares are representatives of the Uspeh line. Comparing the measurements and indices of probands and their parents, significant differences in the indicator are not noted.
Orlov trotters of class 2.05 and faster obtained in 81 variants of rebounds, taking into account the parental affiliation with the genealogical lines. The largest number of Orlov trotters of class 2.05 was obtained in the Pion line. 93 fathers (34.2 %) and 70 mothers (25.7 %) belong to it. The second and third places, respectively, were occupied by the Pilot and Boltik lines. Only 20 heads (7.4 %) were obtained with in-line rebounds. Crosses of three lines to be the most effective combinations: Pion, Pilot, Boltik (75 heads – 27.5 %).
The largest number of Orlov trotters of class 2.05 was obtained with outlying inbreeding with a coefficient of 0.1-1.0 % – 101 heads (37.1 %). The average level of inbreeding (n = 272) was 1.7 %, 40 heads, or 14.7 % were outbred.

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