Show Jumping Competition Research Articles

Comparison of blood parameters in two genetically different groups of horses for functional longevity in show jumping

IntroductionIn order to find early selection criteria to improve the longevity of show jumping horses, a specific protocol was designed.MethodsBefore entering competition, young horses selected from extreme stallions for longevity were measured for many traits, including blood parameters. Blood samples were taken from 952 horses aged 2–4 years old, sired by two groups of stallions: one with unfavorable (U) and the other with favorable (F) extreme estimated breeding values for functional longevity. These breeding values were previously calculated from data on 202,320 horses that participated in show jumping competitions between 1985 and 2022. Functional longevity was defined as time spent in competition, adjusted for the level of performance. The 59 measured parameters included hematology, proteins, cytokines, liver and kidney function, bone and joint health, oxidative stress and endocrinology. Heritability was estimated using a mixed model that accounted for the effect of age, sex, estimated weight, visit (place and date of collection), and animal random additive value with 10,280 horses in pedigree. A Partial Least Square logistic regression was performed to predict the sire group.ResultsAge, sex and estimated weight significantly affected 36, 19 and 16 variables, respectively. The visit had a significant effect on all variables. Heritability estimates were high, with 75% higher than 0.20% and 30% higher than 0.50. The most heritable traits included mean corpuscular volume (0.92, se 0.11), mean corpuscular hemoglobin (0.90, se 0.11), white blood cells (0.55, se 0.13), total alkaline phosphatase (0.68, se 0.12) and percentage of γ-globulin (0.57, se 0.12). The logistic regression that predicted the group of sires favorable for longevity identified 16 significant variables. Key findings included: lower mean corpuscular hemoglobin (p-value < 0.001), lower mean corpuscular volume (p-value < 0.001), lower number of white blood cells (p-value < 0.01), higher percentage of intestinal and bone alkaline phosphatase (p-value < 0.01) for a lower total alkaline phosphatase (p-value < 0.01), higher percentage of α2-globulin (p-value < 0.001) and lower percentage of β1-globulin (p-value < 0.01).DiscussionBlood parameters measured at rest in young horses may be predictive of their genetic value for functional longevity in show jumping.

Return of showjumping horses to sporting activity after colic surgery.

The return to performance after colic surgery is crucial for competition horses. While studies have investigated racehorse performance following colic surgery by analysing racing participation and earnings, this approach does not apply to showjumping horses, leaving a gap in the literature regarding their objective performance evaluation. To assess the short- and long-term survival and return to performance in showjumping horses after colic surgery. Retrospective case series. Medical records of horses with acute colic requiring surgical treatment were analysed, and data for showjumping horses (Group 1) were retrieved. Telephone follow-ups were conducted and national competition databases were used to collect pre- and postoperative showjumping competition entries for Group 1 and for randomly selected horses (Group 2) participating in the same competitions as a comparison group. Of 253 horses undergoing colic surgery, 96 were recorded as showjumpers. The median long-term survival was 2.73 (0.01-6.14) years. Among these horses, 59 were competing at the time of surgery, and of these, 46 (78%) returned to competition and 41 (89.1%) competed at the same or higher level, while 5 (10.9%) competed at a lower level. At a 2-year follow-up, 63.6% of the showjumping horses that underwent colic surgery were alive. No significant differences were observed in the level of competition and career length between horses, which underwent colic surgery, and the randomly selected comparison group. Small sample size and a single-centre design. Showjumping horses can make a successful return to competition after colic surgery, with the majority performing at the same or higher level as before the procedure.

Early life jumping traits: Are they good proxies for success in show jumping competitions in Belgian warmblood horses?

The main goal of the Belgian Warmblood horse studbook (BWP) is to breed successful competition horses, with emphasis on show jumping. However, competition results are only available later in life and competition traits are lowly heritable. Hence, the use of phenotypes that record performance-related traits at an early life stage could help increase genetic progress. In this study, we evaluated the potential of eleven linear scored early life jumping traits assessed during jumping in freedom (2-5 years old) or under the saddle (4-6 years old) as proxies for later success in show jumping competitions. To this end, we estimated their heritabilities and genetic correlations with the competition trait, adjusted fence height, by using 2170 free jumping records, 1588 jumping under saddle records, 674,527 show jumping competition records and almost 81,000 informative horses in the pedigree. As participation of young horses in these contests is on a voluntary basis, a pre-selection most probably exists. To verify this hypothesis, we investigated the association between participation to young horse contests and participation to show jumping competitions later on (called here start status phenotype). We also estimated heritabilities for "start status in free jumping contest", "start status in jumping under saddle contest" and "start status in free jumping or jumping under saddle contest" by fitting threshold models. Furthermore, we calculated genetic correlations between these traits and adjusted fence height and calculated the correlations between EBVs for start status in young horse contests and EBVs for success in competitions. Estimated heritabilities of early life jumping traits ranged between 0.05 and 0.30. Their genetic correlations with adjusted fence height were moderate to high (rg = 0.37-0.63). Relatively more horses that participated in young horse contests competed later on compared to horses that did not participate in young horse contests (p-value < 0.001). They were also significantly more successful in show jumping competitions. Furthermore, start status in young horse contests was moderately heritable in BWP horses (h2 = 0.56-0.65) and moderately to highly correlated with later success in competitions (rg = 0.30-0.77). Hence, we showed that ELJ traits are good proxies for later success in competitions and that a pre-selection of horses occurs in young horse contests. It is suggested to stimulate participation to young horse contests to achieve a more representative sample of the population. Early life jumping traits can therefore optimize the genetic progress for show jumping performance.

Equine Herpesvirus-1 Outbreak During a Show-Jumping Competition: A Clinical and Epidemiological Study.

A total of 752 horses were involved in the CES Valencia Spring Tour 2021. Due to an equine herpesvirus-1 (EHV-1) outbreak, the competition was cancelled and the site was locked down. The objective of this study was to describe epidemiological, clinical, diagnostic, and outcome data of the 160 horses remaining in Valencia. Clinical and quantitative polymerase chain reaction (qPCR) data were analysed for 60 horses in a retrospective case-control observational study. The risk of developing clinical manifestations was explored using a logistic regression approach. EHV-1 was detected by qPCR, genotyped as A2254 (ORF30) and isolated on cell culture. From the 60 horses, 50 (83.3%) showed fever, 30 horses (50%) showed no further signs and 20 (40%) showed neurological signs, with eight horses (16%) hospitalised, of which two died (3%). Stallions and geldings were six times more likely to develop EHV-1 infection compared to mares. Horses older than 9 years, or housed in the middle of the tent were more likely to develop EHV-1 myeloencephalopathy (EHM). These data show that for EHV-1 infection, the risk factor was male sex. For EHM the risk factors were age > 9-year old and location in the middle of the tent. These data highlight the crucial role of stable design, position, and ventilation in EHV-outbreaks. It also showed that PCR testing of the horses was important to manage the quarantine.

Adjusted fence height: an improved phenotype for the genetic evaluation of show jumping performance in Warmblood horses

BackgroundShow jumping is one of the most popular disciplines in the horse sector, which makes success in show jumping competitions an important breeding goal for many studbooks. Therefore, the genetic evaluation of show jumping performance is of major interest and this is the case for two Belgian Warmblood studbooks: the Belgian Warmblood horse and Zangersheide. In this study, first an improved phenotype for show jumping performance was developed, i.e. adjusted fence height based on a new non-arbitrary method to scale ranking and competition level, which are two major components of success in competitions. Second, we assessed the importance of including a rider effect in genetic models for show jumping performance, this effect being under debate in sport horse breeding. Third, genetic models based on elementary performances and one model based on a summarized performance were compared in terms of model fit, heritabilities and the stability of estimated breeding values to define the most suitable one for the genetic evaluation of show jumping performance.ResultsIn this study, more than 600,000 Belgian competition records and almost 81,000 horses were used. Genetic evaluations were developed based on elementary performances (Blom-transformed ranking and adjusted fence height) and on a summarized performance (highest level achieved). Estimated heritabilities of Blom-transformed ranking, adjusted fence height and highest level achieved were 0.09, 0.12 and 0.39, respectively. Including a rider effect improved the models for genetic evaluations. Estimated genetic correlations between the studied models were moderate to high (rg = 0.60–0.99). With the best fit model, the accuracy of the estimated breeding value (EBV) for adjusted fence height reached 0.70 for a larger number of stallions and for stallions that tended to be younger.ConclusionsWe recommend breeders to implement this new phenotype ‘adjusted fence height’ in breeding programs. It is moderately to highly correlated with Blom-transformed ranking and highest level achieved, a proxy for lifetime success, and is available for selection candidates from an early age onwards.

Monitoring Performance in Show Jumping Horses: Validity of Non-specific and Discipline-specific Field Exercise Tests for a Practicable Assessment of Aerobic Performance

Show jumping is a highly specialized equestrian discipline that requires technical skill but also power and fitness. Monitoring the horses’ aerobic performance is therefore essential in order to verify whether the training has induced the desired cardiovascular and muscular adaptations. This study therefore aimed at evaluating the validity of non-specific and discipline-specific field exercise tests for objective evaluation of aerobic performance in show jumpers. For this purpose, data obtained from horses competing at Junior and Young Rider level during show jumping competitions as well as field exercise tests were retrospectively analyzed. The effect of the level of difficulty, the horses’ age, the penalty score and the horses’ previous level of performance on blood lactate concentrations after show jumping competitions (100 observations in 49 horses) was evaluated by linear mixed effects models (horse as random effect). Estimated marginal means significantly increased from 140 (4.1 mmol/L) to 150 cm (5.2 mmol/L) classes (P = 0.02). Furthermore, post-exercise lactate values significantly increased with the horses’ age (P = 0.001). Another group of 12 horses performed a standardized incremental field exercise test on a track (SETtrack), a standardized show jumping course (SETcourse) and a standardized grid exercise (SETgrid) each on three consecutive days. Indices of aerobic performance, derived from the SETtrack [velocity at a heart rate of 140 bpm (V140) and at a lactate concentration of 2 mmol/L (VLa2)] were highly correlated with heart rate (V140: r = −0.75, P = 0.005; VLa2: r =−0.66, P = 0.02) and lactate (V140: r = −0.73, P = 0.02; VLa2: r = −0.72, P = 0.02) in response to SETcourse as well as heart rate during SETgrid (V140: r = −0.73, P = 0.02; VLa2: r = −0.76, P = 0.01). Subjective rating of muscular fatigue was significantly correlated to the mean heart rate during SETcourse (r = −0.64, P = 0.05) and SETgrid (r = −0.74, P = 0.02) but not to the aerobic indices calculated from SETtrack. Besides non-specific incremental field tests, performance monitoring in show jumpers should therefore also include discipline-specific tests that more closely reflect the internal load induced by show jumping competitions.

Analysis of the current situation in international show jumping and assessment of the influence of the proportion of Thoroughbred in the pedigree, horse demographics and sport season on the performance of horses

The aim of the research was to monitor current trends in international show jumping and assess how the proportion of Thoroughbred blood in the pedigree of horses, age, breed, sex and sport season influenced the competition results of show-jumping horses at the world level. The research was based on the databases of jumping rankings for the years 2010, 2014 and 2018 published by the International Federation for Equestrian Sports (FEI). All horses from the FEI rankings were included in the database with the exception of ponies and also horses lacking basic data. This yielded a total of 14,980 horses. The rankings of horses were calculated according to FEI methodology on the basis of the best 30 results every year in international show-jumping competitions with a minimum fence height of 1.45 m. The most represented breed was the Dutch Warmblood (19.26%) and the most common sex was gelding (43.98%). Since 2010 the standard proportion of Thoroughbred blood in the pedigrees of show-jumping horses has decreased and in 2018 the average proportion of Thoroughbred in the pedigree was 41.61%. The analysis of the statistics in the whole database established a significant (P ˂ 0.01) influence of all observed factors. The horses achieved a statistically higher ranking in 2018 (117.57) than in 2010 (98.33) and 2014 (105.93). The groups with a proportion of Thoroughbred between 30.10 and 70.00% achieved a significantly higher ranking than horses with a zero proportion of Thoroughbred in the pedigree. Stallions achieved a significantly higher ranking (117.84 points) compared to geldings (105.76 points) and mares (104.66 points). The horses aged 10–13 years old achieved better results (124.71 points) than the younger group of horses (76.66 points) and older group of horses (109.29 points, P = 0.0033). Statistically conclusive differences were found between AES horses (162.81 points) and the group of non-sport horse breeds (68.26 points) and also between AES horses and horses of unknown pedigree (38.61 points). There were no significant differences between the principal warmblood sport breeds produced in Europe.

Performance analysis of faults at international showjumping competition

Performance analysis of faults at international showjumping competition

Comparing subjective and objective evaluation of show jumping competition and warm-up arena surfaces

The development of safety and quality standards for equestrian surfaces needs to be based on objective, repeatable measurements which allow comparisons between surfaces. These measurements should incorporate the assessment of surface performance by riders. This study provides data from objective and subjective assessment of functional properties of high-level show jumping competition and warm-up arenas. Twenty-five arenas in nine international show jumping events were evaluated by mechanical in-situ testing with a surface tester, rider assessments using visual analogue scales (198 riders provided 749 arena evaluations), descriptions of arena constructions and by laboratory tests of surface material. Mixed models were used to present subjective evaluation of rider perception of the functional properties for each arena while controlling for rider and event. The association between objective and subjective assessments were also explored creating mixed models, controlling for rider and event.Mechanical measurements of impact firmness, and to a lesser extent cushioning and grip, had a significant positive association with the riders’ perception. Responsiveness as assessed by the Orono biomechanical surface tester (OBST) was negatively associated with the riders’ perceptions, which suggests riders and the OBST had different concepts of this functional property and that further developments of the OBST might be necessary. Objectively measured uniformity showed no useful association with riders’ perception. Even though arena assessments were made by top level riders, a substantial inter-rider variation was demonstrated.

Lipid and Lipoprotein Profiles Modification in Athletic Horses After Repeated Jumping Events

The aim of this study was to evaluate the effect of physical exercise on serum nonesterified fatty acids (NEFAs), triglycerides, total cholesterol (total chol), high-density lipoproteins (HDLs), low-density lipoproteins (LDLs), and very low–density lipoprotein (VLDL) fraction levels in Jumper horses. Horses took part to a show jumping competition represented by repeated events. Blood sampling was performed before the first day of competition (T0), within 10 minutes from the end of each competition (T1POST, T2POST, T3POST), and in the day after competition (R1). Statistical analysis showed a significant effect of exercise (P < .001) on all studied parameters. Nonesterified fatty acids showed higher values at T1POST, T2POST, and T3POST than T0. Higher serum triglycerides, VLDLs, and HDLs levels were found at T1POST, T2POST, T3POST, and R1 than T0. Total cholesterol and LDLs values showed a significant decrease at T1POST, T2POST, T3POST, and R1 than T0. The observed changes in lipid and lipoprotein parameters could represent the metabolic response to physical exercise during the 3 days of competition that led to an increase of NEFAs and triglycerides levels after the physical exercise which act as energy support, whereas during the recovery period, the energy production was assured by oxidation of serum triglycerides. The increase in serum HDLs, decrease in total chol, and LDLs point out the positive effects of physical exercise on the lipoproteins profile in trained horses suggesting the reverse cholesterol transport from peripheral tissues to the liver for new biochemical processes in trained Jumper horses.

6. Genetic Evaluation of Show Jumping Horses in the Slovak Republic

Abstract The aim of this study was to estimate genetic parameters and breeding values (BVs) of show jumping horses in the Slovak Republic. The data from show jumping competitions performed in 2004-2013 (The Slovak Equestrian Federation) and data from the Breeding Information Register (The National Stud Farm in Topo’čianky) were used in our work. There were 831 horses (4-21 years old) included in the analysis. The level of competitions ranged from LS (125 cm) to TT (160 cm). Profit of penalty points (PP) and ranking in the competition (R) were analyzed as the measures describing horse performance. The average profit of PP was 5.90±6.28, and mean R was 20.20±16.88. The software package CFC 1.0 was used for computation of inbreeding coefficient (F) in given population. The ratio of inbred animals was 74.49% from 831 investigated animals. The average F value was 0.0068 within inbred population. Input data (profit of PP and R) were not normally distributed, therefore the transformation by Blom formula was made. The height of obstacles was taken into account. The ranking in competition has been nearest to the normal distribution even though the tests of normality have not confirmed it significantly. The heritability coefficient was 0.17 in PP and 0.10 in R. The BVs were estimated for PP and R (BVPP, BVR). The BVs for R were modified to the form of relative breeding values (RBVR). The increase of genetic level of R within population of show jumping horses has been observed in recent years.

Serum muscle-derived enzymes response during show jumping competition in horse.

Aim:The effect of two jumping competitions, performed in two consecutive weekends, on serum creatine phosphokinase (CPK), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH), urea, creatinine (CREA) concentrations were evaluated in 12 healthy jumper horses.Materials and Methods:Blood sampling was performed before the 1st day of competition (T0), at the end of each show (J1, J2), on the day after the competition (T1); the same sampling plan was followed during the second weekend (J3, J4 and T2).Results:One-way repeated measures analysis of variance showed an increase in CPK at J1 and J2 respect to T0 and at J3 and J4 respect to all other time points (p<0.05). LDH activity showed an increase at J2 respect to T0, at J3 respect to T0, J1, J2 and at J4 respect to all other time points (p<0.05). AST values increased at J1 and J2 respect to T0 (p<0.05). A significant increase of CREA was found at J3 respect to T0, T1 and J1 and at J4 respect to all other time points (p<0.05). A decrease in serum urea levels was found at J1 respect to T0, at J2 and J4 respect to T0 and T1; at T2 respect to T0 (p<0.05). A positive correlation between urea/CPK (p=0.0042, r2=0.030), LDH/CPK (p<0.0001, r2=0.535), CREA/LDH (p<0.0001, r2=0.263), CREA/CPK (p<0.0001, r2=0.496) was observed.Conclusion:Our results suggest that 5 days recovery period between the two consecutive competition weekends is insufficient to allow muscle recovery and avoid potential additional stress. The findings obtained in this study improve the knowledge about metabolic changes occurring in athlete horse during the competition to identify muscle alterations following show jumping competitions.

Development of personality tests to use in the field, stable over time and across situations, and linked to horses' show jumping performance

This study aimed to identify tests that include all the criteria necessary to characterise reliably the personality of horses on a large scale: stability of measures across situations and over time, evaluation of independent dimensions, links with use and easy to organise for a large number of animals. For this purpose, two independent experiments were carried out, involving respectively 24 (experiment 1) and 15 horses (experiment 2). Existing tests were adapted to facilitate their use during breeding horse shows, while their owners held their horses in hand. They were called the “Simplified Personality Tests” (SPT). They involved three fear tests (novel surface, novel object and suddenness), two tactile sensitivity tests (Von Frey filament and hip-stifle axis stimulation) and behavioural measurements conducted during standard horse show tests (assessment of horse conformation and jumping ability). Following the first experiment, it was demonstrated that the measurements carried out during two of the fear tests were significantly correlated (correlations between “novel surface” and “suddenness”: R=0.42, p=0.04, N=24), as was also the case for the two tactile sensitivity measures (correlation between “filaments” and “hip-stifle axis” R=0.50, p=0.01, N=24). However, the fear and tactile sensitivity measures were not correlated, indicating that they reflected independent dimensions. To test for stability across time, we checked whether the measurements performed during these SPT correlated with equivalent measurements recorded from another series of tests (“Complete Personality Tests”) obtained one month earlier and whose stability over several years had previously been demonstrated. These correlations were all significant except for the “novel object test”. Thus, except for the latter test, all measures were stable across situations and over time and evaluated two independent dimensions: fearfulness (disposition to react to a greater or lesser extent to new or sudden stimuli) and tactile sensitivity (disposition to react to a greater or lesser extent to tactile stimulation). To determine the relationship between these measures and the horse's behaviour while competing in show jumping competitions, we observed horses ridden during training sessions or competitions one month (experiment 1) or one year (experiment 2) after the tests. Principal component analyses showed that such relationships existed: the most fearful and to a lesser extent the least sensitive horses were more difficult to ride, but performed better when competing because they knocked down fewer bars. Finally, these tests were conducted on more than 650 horses over three years, demonstrating that they are easy to organise on a large scale.

Serum iron, ferritin, transferrin and haptoglobin concentration variations during repeated show jumping competition in horse

Modifications of the iron profile in athlete horses during two international three star (***) show jumping competitions performed in two consecutive weekends were evaluated. Serum iron, ferritin, transferrin, and haptoglobin were assessed in 12 well-trained Italian Saddle horses. Blood samplings were performed before the first day of competition (R1), within 10 min from the end of each competition (J1, J2) and on the day after competition (R2). The same plan was followed during the second weekend (J3, J4 and R3). One-way repeated measures analysis of variance (ANOVA) was applied on obtained data, and a significant effect of exercise (P &lt; 0.05) on all studied indices was found. These results suggest that serum iron, transferrin, ferritin and haptoglobin are responsive to intense exercise and could be considered important indicators that may give important information about the horse’s performance.

Comparison of models to estimate genetic parameters for scores of competitive sport horse events in the Czech Republic

The objective of the present study was to estimate genetic parameters and predict breeding values of sport horses in the Czech Republic using animal model variations. The data set for the evaluation was composed of edited records of show jumping competitions in the Czech Republic in years 1991-2013. Input data were not normally distributed; hence Blom transformation was used for the variable filtration. The Gibbs sampling algorithm was used for the genetic parameters estimation. Two models were examined. The first was a random regression model including the effect of a horse's experience in competition (expressed as the length of the horse's sporting career in days), fixed effects of sex, age, and event, and random effects of rider, permanent environment, and animal. The second model was a multi-trait model with fixed effects for sex, age, and event and random effects for rider, permanent environment, and animal. In this latter case, horse performance was classified as three traits. The first trait was jumping results from obstacle heights of 90-110 cm, the second of 120-135 cm, and the third of 140-155 cm. In the random regression model, heritability estimates ranged from 0.01 to 0.11; whereas in the multi-trait model, heritabilities were 0.07, 0.11, and 0.14 for the first, second, and third trait, respectively. Results indicate that both models could be used to predict breeding values of sport horses in the Czech Republic. The multi-trait model revealed that heritability estimates increased with the increasing height of obstacle. In the random regression model, breeding values differed according to a horse's experience in competition, allowing adjustment of the breeding value for the environmental effect of a past experience.

Competition Jumping Horses: Effects of Age, Sex and Breed on the Fei/Wbfsh World Ranking

The breed, age and sex of the horses are all important factors in determining the future rank in international high-level show jumping competition and this is the reason why we choose to analyze these factors. The objective of this study was to analyze the differences between the top jumping horses in the world regarding breed, sex and age, and to investigate the impact of these factors on the average number of FEI points gained in the last year. For this research, we examine the first 103 jumping horses from FEI&WBFSH World Ranking List for Jumping Horses April 2014, divided in 6 groups for breed variable and 3 groups for sex and age variables. The results show that 82.5% of the horses have between 10 and 14 years, 10.7% have less than 10 years and only 6.8% have more than 14 years. For breed variable, the results show that 34% of the horses belong to warmblood breeds from Germany (34.3% HOLST, 20% OLDBG, 20% WESTF, 17.1% HANN, 5.7% BRAND and 2.9% Thuringer), 26.2% belong to warmblood breeds from Belgium (11.1% ZANG, 70.4% BWP and 18.5% SBS), 18.4% belong to warmblood breeds from The Nederland (94.7% KWPN and 5.3% NRPS), 9.7% belong to warmblood breeds from Great Britain (70% AES, 20% ISH and 10% SSH), 8.7% belong to warmblood breeds from France (100% SF) and 2.9% belong to warmblood breeds from Sweden (100% SWB). The average number of FEI points gain in the last year was evaluated as not being significantly different (p>0.05) for any of the variable considered for this study. In the present research work, we demonstrated that for performance in show jumping competition at the highest levels it is necessary a horse from a sport breed with a strict selection and not one from a traditional breed, and that between the principal warmblood breeds grown in Europe there are no significant differences.

Coincidences between molecular genetic and studbook data of gidrán mare families on the basis of mtDnA

The traditional Hungarian horse breed, Gidran has been close to the edge of extinction several times. Despite the multiple bottleneck effect, the breed has retained a part of its genetic variability, and performed prominently in carriage driving and show-jumping competitions. Maintaining of the Gidran breed is important in the point of view of world heritage; because besides Hungary, smaller Gidran populations exist only in Bulgaria and Romania. Taking advantage of the special inheritance features of mtDNA, our study focused on two mtDNA regions of Gidran mares. Altogether, 251 hair samples from various Hungarian studs were examined. The analysis was successfully made in case of 251 samples of the cytochrome b and in case of 246 samples of D-loop regions. Because of the distinct mutation rates of the two mtDNA markers, the number of the haplotypes and the way of grouping samples into haplotypes was different. Our key finding was that most haplotypes may be compatible with mare families of the stud book; however incidental mistakes in stud book have occurred only in a few cases. Our results indicate the importance of the preservation and breeding those mare families, which are molecular genetically more diverse than the others, and are in the edge of extinction.

Dynamics of Total and Free Iodothyronines of Jumping Horses on the Responses to Competition and Transport

The aim of the research was to study the total and free iodothyronine (T3, T4, fT3, fT4) changes of trained horses transported before and/or after competition, and performing in show jumping competition, respectively. Six horses were studied in four different sessions during four consecutive weeks. During the first week, horses were submitted to transport before competition (sessions: t0 = before transport, T0 = after transport). Then, during the second week, horses were submitted to transport after competition (sessions: t1 = before transport, T1 = after transport). During the third week, horses participated in a competitive show jumping event (sessions: t2 = before competition, T2 = after competition). During the fourth week, horses were submitted to transport and to a competitive show jumping event (sessions: t3 = after transport and before exercise, T3 = after exercise). Compared with t0 session, t1 showed higher T3 (P < .01) and lower fT4 (P < .01) concentrations. Compared with t2 session, t3 showed higher T3 (P < .01) and lower fT3 (P < .01) concentrations. A significant effect of competition on fT3 changes (F = 4.227; P < .05) was recorded. The results obtained showed that transport and show jumping competition differently influenced the thyroid responses of trained sport horses to physiological and psychological stress, also according to the individual experimental sessions.

POROVNÁNÍ PLEMENÍKŮ PODLE VÝSLEDKŮ JEJICH POTOMKŮ V KRITÉRIÍCH MLADÝCH KONÍ

The objective of the study was to evaluate and compare sires based on results of their offspring in the Criteria of Young Horses. The Criteria of Young Horses are intended for stallions and mares of 4 to 6 years of age. The competitions are announced by the Czech Equestrian Federation in co-operation with breeders’ associations of the Bohemian warm-blood, Slovakian warm-blood, Kinský horse and Moravian warm-blood breeds. The horses were evaluated in the arena by the assessor and given three marks: for show jumping, agility and readiness of the horse. Data were obtained in co-operation with the Czech Equestrian Federation. Evaluated were the results of the Criteria of Young Horses in show jumping competitions held in 1998–2007. Only sires with 7 and more offspring were assessed. Ana­ly­sis of variance was carried out followed by tests according to Scheffe. The Excel 2003 and Statistica version 8 were used for processing the database and for statistical processing. Comparisons based on marks given by the assessor in the arena showed that the highest-placed stallion was Acord II and was followed by Catango Z, Calido I and Landos. The offspring of the Hanoverian stallion Walzerkönig were the lowest-placed; the second worst-placed were the offspring of Diktant slatiňanský, a stallion of Czech origin. The differences among these stallions were statistically significant. In comparisons based on marks as the second indicator, the offspring of stallions Acord II, Catango Z and Ascot were the highest-placed and offspring of stallion Diktant slatiňanský were the lowest-placed. The dif­fe­rence between these stallions was statistically significant. Based on the third indicator the offspring of stallions Acord II and Catango Z were the highest-placed. By contrast, the worst were offspring of stallions Duramus II and Duman. The differences between Acord II and Duramus II were statistically significant. According to the resulting total evaluation the highest rating went to offspring of stallion Acord II, followed by Catango Z, Autonom s.v. and Landos. The worst rating went to offspring of stallions Duman, Walzerkönig, Cattaro and Diktant slatiňanský. Comparisons showed that the dif­fe­rences were statistically significant only between Acord II and Diktant slatiňanský.

Evaluation of Serum Electrolytes and Blood Lactate Concentration During Repeated Maximal Exercise in Horse

Modifications of some serum electrolyte concentration during two international *** show jumping competition performed in two consecutive weekends were evaluated. Serum sodium (Na), chloride (Cl), magnesium (Mg), potassium (K), phosphorous (P), calcium (Ca), iron (Fe), and blood lactate on 14 well-trained Italian saddle horses were assessed. Blood samples were collected before the beginning of the competition (T0B), within 10 minutes after the end of race (R1, R2, and R3), and on the day after competition (T0R). The same procedure was followed on the second weekend (R4, R5, R6, and T1R). One-way repeated measures analysis of variance was applied on collected data, and a significant effect on sampling time (P < .05) on all parameters studied was found. These results suggest that serum electrolytes and blood lactate concentration are responsive to intense exercise and could be considered an important factor for a correct management training's planning.