SOURCES OF SPECIFIC VARIANCE AND GENETIC PARAMETERS OF TYPE AND CONFORMATION IN 2-YEARS OLD HORSES FROM THE EAST BULGARIAN BREED

Iliyana Sabeva, Maya Popova

Abstract: The aim of present study was to established sources of specific variance and genetic parameters of type and exterior in 2-years old horses from the East Bulgarian breed. The study was carried out on the basis of data from the assessment of type and exterior of 225 East Bulgarian horses at age of two, tested during the period of 2006–2016. There was a relatively constant structure of judging committee. A 10-score system with accuracy to 0.5 was used. The examined traits was evaluated took account the follow criteria: suggestive features of the breed and overall impression for type, and for exterior – head, neck and corpus, legs and constitution (physique). Registration of animals and traits was made by Association East Bulgarian Horse. Analyses of variance,
estimations of different sources of variability, heritability and correlations were made by mixed model methodology. Family belonging of horses, lineal belonging of dams, sires and year of birth were statistically proven sources of phenotypic variance. The influence of month of birth was proven only for type. The representatives of Ohota, Nerazdelna and Likuiushta families, and mares’ progeny from the lines of Devis Own, Dampfross, Adeptus XX, Cor De La Bryere, Ladykiller, Gagne Si Peu and Tempelhuter possessed well expressed positive effects regard the traits type and exterior. Heritability values were varied from 0.62 to 0.84 for type and respectable from 0.34 to 0.53 for exterior.
There was a high phenotypic and genetic correlation between examined traits. The biggest part of phenotypic variety at two years of age was generated mainly by genetic sources of variability.

Keywords: 2-years old sport horse; conformation; correlation; heritability; performance test; sport breeds; type

Date published: 2018-05-28