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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 study aimed at testing the hypothesis that mares’ fearfulness is a potential factor differentiating the level of their maternal behaviour. Twenty purebred Arab mares were used. In part one of the study fearfulness of mares without foals was assessed by their behavioural reactivity and heart rate in response to rotating black-white squares (fearfulness test). On that basis the mares were classified into three groups: (1) fearless, n=8, (2) medium-fearful, n=7 and (3) fearful, n=5. In part two,maternal behaviour of mares was assessed in two sessions of separation test: 3 min dam’s partial separation from foal (mare out of box, but with visual, auditory and olfactory contact with foal) and 3 min full separation (mare out of stable, no contact with foal). Locomotor activity, vocalization and defecation frequency as well as heart rate in mares were recorded during both separation tests. The results showed a relation between mares’ fearfulness and their maternal behaviour. Fearless dams vocalized more (10.63±5.32, mean rank 13.00, P<0.05) and showed higher heart rate (138.00±22.66 beats/min, mean rank 15.40, P<0.05) when totally separated from their foals, compared to fearful dams (4.00±3.74 calls, mean rank 6.10; 116.00±20.32 beats/min, mean rank 7.23, P<0.05). Thus, fearless dams generally displayed higher maternal ability which is vitally important in successful breeding. In conclusion, selecting for low fearfulness ensures appropriate maternal behaviour of the brood mares.
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 matings and selection of horses for the breeding stock in national Arabian horse studs from the 1947-1948 to 1996-1997 seasons were analysed. The data were examined taking into account the average values of the inbreeding coefficient (F). It was stated that breeders constantly avoided mating highly-related horses. Matings which concluded in abortion exhibited a higher level of inbreeding, while those which were either barren or ended in the death of the foal were characterised by lower average values of the inbreeding coefficient. In the selection of horses for the breeding stock, breeders preferred stallions with lower inbreeding coefficients. Moreover, among the stallions of the same father those with F values below the average were selected (statistically significant regularity). This tendency, however, was not observed in the selection of mares.
Flexor tendonitis and suspensory desmitis are among most prevalent musculoskeletal injuries observed in racehorses. The aim of this study was to determine which horse and race-related parameters can help to diminish the possibility of injury or – when injury has occurred – to evaluate the potential for the horse to continue a successful career after convalescence. Special attention was given to the comparison of Arabian and Thoroughbred racehorses. 187 horses with ultrasonographically visible lesions were included in the study. Following parameters were analyzed: structure (Superficial Digital Flexor Tendon [SDFT], Deep Digital Flexor Tendon [DDFT], Suspensory Ligament [SL]); percentage of cross sectional area increase; hypoechogenic lesion character; in horses with SDF tendonitis – tendonitis grade according to Genovese. This study showed that Thoroughbreds are more at risk of musculoskeletal problems than Arabian racehorses. In both breeds, the most frequent injuries concern SDFT, then SL. Over 95% of tendonitis concern forelimbs. In Thoroughbreds, the prevalence of tendonitis is higher in bigger horses, in males when compared to females and in fence / steeple racehorses when compared to flat track racehorses. The inside limb is more at risk of SDF tendonitis, when the external limb – of SL desmitis. Tendonitis severity increases with age and is greater in steeplechasers when compared to flat track racehorses. The outcome of tendonitis without hypoechogenic lesion is much better than that with hypoechogenic lesion. Evaluation of hypoechogenic lesion length is an easy and accurate prognosis tool, as the chances of returning to racing drop dramatically with lesions longer than 12 cm.
In this study, show-jumping horses (n = 80) and Arabian race horses (n = 80) from different work groups were examined, with the guidance of 2-D, by M-Mode echocardiography, to establish the reference values and to determine the differences in the cardiac structural measurements. Measurements were performed in four different planes by obtaining M-Mode cross-sections from M. papillaris, C. tendinei, mitral valves and aorta root levels, with the guidance of 2-D in the 4th intercostal space. Left ventricle, right ventricle, left atrium, aorta root, interventriculer septum, left ventricle posterior wall and heart wall movements were observed and end-systolic and end-diastolic diameters with left ventricle function evaluations were performed. Subsequently, all of these values were compared between the two groups. The results indicated statistical significance of P < 0.001 in end-diastolic volume (EDV) and ejection fraction (EF), and P < 0.005 in diastolic left ventricle internal diameter (LVIDd), diastolic interventricular septum thickness (IVSd), diastolic right ventricle internal diameter (RVd), diastolic aorta internal diameter (Aod), fractional shortening (FS) and cardiac output (CO). It has been concluded that Arabian race horses are more advantageous with their powerful left ventricle functions, while show-jumping horses have the benefit of possessing wider left ventricles, indicating the probability that exercise improves the left ventricle functions in horses.
Successes in breeding of all animal species are mostly determined by high reproductive indices. That´s why tested were 127 purebred Arabian stallions used in Polish breeding in the years 1971-1998, siring 5 or more heads of progeny. For every stallion collected were data concerning number of mares bred, born foals, open periods, abortions, stillborn, dead or destroyed foals, as well as mares, who died being in foal to a given stallion. There was found an increase of intensivity of reproductive utilization of leading sires in the tested period, compared with earlier seasons. At the same time observed was, however, a more frequent occurrence of undesirable traits. Currently prolonged sirelines distinguished themselves with higher reproductive indices. There was observed also a higher share of stallions siring 5 or more heads of progeny per stallion and season. On the other hand, reducing representation of sirelines continued in our breeding might cause unwanted changes in the genetic pool of our broodmares´band, prevented by the Program of Purebred Arabian Horse Breeding in Poland.
In a group of purebred Arab mares the level of inbreeding and its effect on three body conformation traits was determined. Moreover, estimated were heritability coefficients of the traits and their phenotypic,genetic and environmental trends. Considered were conformation records of 706 Arab mares born in the years 1936- 1993. The mean inbreeding level of mares was 0.88%. No considerable effect of inbred rate on body conformation traits was found. The obtained partial regression coefficients were close to zero. Heritability coefficients appeared low and amounted to 0.160 (±0.078) for height at withers, 0.052 (±0.067) for chest circumference and 0.050 (±0.054) for circumference of cannon.Negligible positive genetic trend was observed for all the traits studied, whereas the environmental trends were not clear.
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