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Abstract

The dynamics of the ratio of Orlov’s Trotting breed horses color of the over the past 85–90 years, recorded in the State book of breeding horses at different times, as well as included in the class 2 min.10 sec. and 2 min. 5 sec.
The ratio of of Orlov’s Trotting breed horses color is quite significantly changed. Because since pre-revolutionary times were in Vogue horse black. Over time, gray horses have become popular as more attractive visually. This was facilitated by their Arabized head and body type.
It was determined that from 1935 to 2017 the share of gray horses increased significantly-from 37 to 51 %, or 1.6 times. However, the number of Orlov Trotters, recorded in the State book of breeding horses, significantly decreased: stallions – 8.8, and mares – 4 times.
Orlov’s Trotters of class 2.10 do not differ significantly in the ratio of color. From 2166 goals, recorded in catalogue (as on 01.01.2013) gray stallions and mares – 54,6 %, Vogue – 27,2 %, black – 15,2 % and redheads – 3 %.
Some researchers have argued that genetically grey color is associated with a manifestation of high performance in horses of all-fasting breeds, others – a bay.
The collected and analyzed material shows that among the Orlov’s Trotters of class 2.05 of different colors there is no significant difference in the liveliness of 1600 meters. However, the 12 Bay Orlov’s Trotters  of class 2.05 of the Barchuk line have an average age of recordsetting – 4.83, which is 4.4%. Ten black Orlov’s Trotters horses of Pion linereached the best speed in 5 years (3.7 percent), and 41 gray horses of the Pilot line showed its best own liveliness at 5.41 years (15.1 %).
The greatest number of Orlov’s Trotters horses class 2.05 received under heels informal parents 60 goals (22 %). By the combination of grey and Bay pairs were received 83 horses (30.5%) with speed 2.05 class.
According to the above data, a clear link between the horse color and  its performance, although it is known that the color of the skin and hair has a certain biological significance in the ontogeny of animals. In addition to the protective function in the area of distribution of ancestors of the horse noticed that in domestic horses on the white limbs often appears slimy, and light hoof horn weaker from black. So, we have proved that the intensity of all-fasting horses is not due to their color. It is the result of the interaction of a complex of genetic factors that ensure high performance of the horse of any color.

References

1. Beljaev, M. M. (1947). Okraska zhivotnyh i estestvennyj otbor – Animal coloring and natural selection. Moskwa: Sov. nauka [in Russian].
2. Bobylev, I. F. (1984). Cena chistokrovnoj loshadi [The price of thoroughbred horses] Konevodstvo i konnyj sport – Horse breeding and equestrian sport, 7, 7-9 [in Russian].
3. Bochkarev, K. P. (1984). Pegie i chubarye [Piebald and flea-bitten]. Konevodstvo i konnyj sport – Horse breeding and equestrian sport, 6, 14-16 [in Russian].
4. Dusenbaev, K., & Fedotov, P., Akimbekov, B. (1970). Mast’ i rezvost’ [The color and speed]. Konevodstvo i konnyj sport – Horse breeding and equestrian sport, 6, 18–19 [in Russian].
5. Krasnikov, A. M. (1957). Jekster’er loshadi – The exterior of the horse. Leningrad : Sel’hozizdat. [in Russian].
6. Kurskaja, V. A. (2012). Masti loshadej – Color of the horses. (2nd ed., rev.). Moskwa : Izvestija [in Russian].
7. Kurskaja, V. A. (2015). Nasledovanie mastej: sovremennoe sostojanie izuchenija voprosa [Inheritance of color: the current state of the study]. Konevodstvo i konnyj sport – Horse breeding and equestrian sport, 4, 17-19 [in Russian].
8. Lipping, V. O. (1971). Mast’ i ee znachenie [Colort and its meaning]. Konevodstvo i konnyj sport – Horse breeding and equestrian sport, 3, 13–16 [in Russian].
9. Tezio, F. (2002). Razvedenie skakovyh loshadej – Breeding of racehorses. red. D. Balakshina, T. Tihonovoj). Moskwa : AKVARIUM LTD [in Russian].
10. Troickij, B. V. (1969). Zagadka seroj masti [The mystery of the gray color]. Konevodstvo i konnyj sport – Horse breeding and equestrian sport, 2, 17–18 [in Russian].
11. Jakovlev, D. (1991). Belorozhdennye loshadi [Horses are born white]. Konevodstvo i konnyj sport – Horse breeding and equestrian sport, 10, 38 [in Russian].
12. Equine Melanoma Vaccines – 2018 [Електронний ресурс]. – Retrieved from: https://thehorse.com/18816/equine-melanoma-vaccines/
13. Hauswirth R. Mutationsin MITF and PAX3 Cause «Splashed White» and Other White Spotting Phenotypesin Horses. PLoSGenetics. 2012. – № 4. [Електронний ресурс]. – Retrieved from: https://journals.plos.org/plosgenetics