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Tested were 1788 purebred Arabian fillies and colts raced during the following periods: I (seasons 1927-1939), II (seasons 1946-1961) and III (seasons 1962-1992). There were divided into groups according to quantities of horses submitted to performance trials (more than 20 heads, 5-20 and less than 5 ones). It was found, that in greater herds more often occurred extreme values of coefficients of success per head. The highest value was observed in the I period and resulted 1.73.
The objective of this study was to estimate variance components of Polish Arab horses’ racing performance. The traits studied were the log of annual earnings and rank. Fixed effects of the year of race, herd, sex, the annual number of starts and random animal and permanent environment effects were evaluated on both earnings and rank at finish in Polish Arab horses. The obtained data included 2243 records on 4- and 5-year-old horses by 143 sires. Only races in which 4- and 5-year-olds competed were used. Heritability estimates of earnings and rank at finish were 0.22 and 0.25, respectively. Repeatability estimates of these traits were the same as heritability estimates. All the estimates of genetic and phenotypic correlations between the log of earnings and rank at finish were high and positive. Earnings and rank are good criteria for genetic improvement. Rank seems to be a better measure of racing performance.
The study aimed at estimating variance components of racing ability traits in Polish Arab horses as a contribution to defining the breeding objective for the breed. Data collected were 8754 placings at finish (square root), 5805 earnings (log), and 1317 numbers of annual starts (square root) of 928 horses running in races over the years 1998-2001. Age of horses ranged from 3 to 10 years, and the distances were from 1400 m to 3000 m. Horses came from 4 state studs and from private (Polish and foreign) breeders. Variance components were estimated by the REML method. Statistical analysis accounted for fixed effects of race within year, age, sex, weight carried and distance, and for the random effects of rider and permanent environment, as well as additive genetic effect of an animal. Model for number of starts within a season omitted the race, rider, weight carried, and distance effects. Pedigrees were at least three generations deep. Heritability coefficients were 0.14, 0.25 and 0.12, and repeatability 0.29, 0.47 and 0.23 for earnings, placings at finish and annual number of starts, respectively.
The objective of this study was to estimate genetic trends in the Polish Arab horses population. Annual earnings and rank at finish in fiat races of Polish Arab horses from 1951 to 1993 were analysed with a BLUP animal model. The collected data included 2,234 records of 1,640 4- and 5-year old horses from 143 sires. Only races, in which horses of at least two mentioned age groups took part, were taken into consideration. The model included an individual additive genetic effect as random, the year of race, herd, sex, age, number of starts and the year of race X age effects as fixed effects. Genetic trends were estimated from differences between horses belonging to different age groups and racing in the same year. The annual genetic gains from 1951 to 1993 were 3.5% and 12.3% of the genetic standard deviation for the log of earnings and rank at finish, respectively. Although the main role in breeding Arab horses is played by beauty and exterior, small genetic progress in the log of earnings and rank at finish was obtained.
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