Horse Population Research Articles

Prevalence of gastrointestinal and blood parasites in horses of Nakhon Si Thammarat province, Thailand

Background and Aim: The global prevalence of gastrointestinal (GI) and blood parasite infections in horses is a significant concern due to their substantial impact on morbidity, mortality, and economic losses in the horse industry. In Thailand, limited research has been conducted on these parasites in horse populations, and data from southern Thailand are lacking. Consequently, this study aimed to estimate the prevalence of GI and blood parasites in horses in Nakhon Si Thammarat province, Thailand. Materials and Methods: In total, 79 fecal and blood samples were collected from horses across 11 farms in Nakhon Si Thammarat province. The fecal examination was conducted using simple flotation, formalin-ethyl acetate sedimentation, and a modified McMaster technique. Conventional polymerase chain reaction (PCR) was used to identify blood and strongyle parasites. The influence of sex, age, and body condition score on the prevalence of GI parasites was also analyzed. Results: Six GI parasites were detected: four nematodes (Oxyuris equi, Parascaris equorum, strongyles, and Strongyloides westeri), one trematode (Gastrodiscus aegyptiacus), and one protozoan (Eimeria leuckarti). The overall prevalence of GI parasites was 74.7%, with single strongyle infections accounting for the highest proportion at 50.6%, followed by co-infections of strongyles and G. aegyptiacus at 10.1%. All 11 pooled strongyle samples were positive for cyathostomins and Strongylus vulgaris using conventional PCR with specific primers. Sex was significantly associated with the overall prevalence of GI parasites, whereas both sex and age were significant risk factors for infection by strongyle parasites. Theileria equi was the only blood parasite species detected in the surveyed horses, with a prevalence of 1.3% (n = 1/79). Conclusion: This study is the first to estimate the prevalence of GI and blood parasites in horses from Nakhon Si Thammarat province, Thailand. These findings highlight the importance of implementing control measures against GI parasites and are pivotal for developing effective infection prevention strategies. Keywords: blood parasites, gastrointestinal parasites, horses, southern Thailand.

Low field magnetic resonance imaging of palmar osteochondral fragmentation of the distal phalanx

SummaryBackgroundThe presence of palmar osteochondral fragments of the distal phalanx is a newly recognised cause of foot lameness with only a few cases having been reported.ObjectivesTo describe the low field magnetic resonance imaging (MRI) appearance of palmar articular fragmentation of the distal phalanx and concurrent abnormalities of the distal interphalangeal joint (DIPJ); to investigate the prevalence of these fragments in a population of sports and pleasure horses and their potential clinical significance.Study designRetrospective descriptive case series.MethodsThis is a retrospective descriptive case series in which all Sports and Pleasure horses undergoing standing low‐field MRI of the feet between 2015 and 2023 were reviewed. Appearance, location and number of palmar articular fragments were recorded. When a palmar fragment was present, abnormal findings of the DIPJ were graded.ResultsA total of 855 horses underwent MRI examination of one or both front feet. Palmar osteochondral fragmentation of the distal phalanx was identified in four horses (0.4% prevalence), three Lusitanos and one Warmblood. The age range was 4–17 years old. All fragments were located along the palmarolateral margin of the glenoid of the distal phalanx in front feet. Concurrent imaging abnormalities of the joint were present in all four horses.Main limitationsLack of histopathology.ConclusionsThe prevalence of palmar articular fragments of the distal phalanx was low in this population of horses. Palmar osteochondral fragmentation must be considered when evaluating lameness localised to the foot, since it was identified only in lame limbs and associated with other imaging abnormalities of the DIPJ.

DWINDLING POPULATION OF INDIAN WORKING EQUINES: A WORRYING TREND

The equine species, which includes donkeys, mules, horses, and ponies, have made major contributions to human civilizations all throughout the world. The Indian livestock sector, after an initial decline in period from 2007 - 2012, staged a remarkable comeback during the period from 2012-2019 with an impressive overall growth rate of 4.8%. However, the total population of horses, ponies, mules and donkeys in India is 0.55 million as per the latest livestock census, a decrease by 51.9% over the previous livestock census (2012). The ‘decreasing utility’ due to increasing vehicles and urbanization has been considered as factors for the drastic dip in population. This paper, based on secondary data, aims to provide a concise summary of the current status, growth rate, distribution patterns, and factors leading to the decline in the population of working equines in India. Tabular presentations and graphical representations have been utilized for easy analysis and comparison of population trends across different years.

Influence of Sires on Population Substructure in Dülmen Wild Horses.

The objectives of the present study were to analyze the influence of the stallions employed in the Dülmen wild horses on the genetic diversity and population substructure using Bayesian cluster analysis. The Dülmen wild horse is maintained as a unique horse population exposed to the natural conditions all year round in the Merfelder Bruch near Dülmen in Westphalia, Germany. Stallions selected for breeding have to prove their abilities to survive under this harsh environment. We used multilocus genotypic information from a set of 29 autosomal microsatellites to determine the paternity of 185 male foals sired by nine stallions. As females could not be sampled, we could not make inferences on all yearlings and test whether there are differences in the genetic population parameters between both sexes. The mean number of progeny was 19.92 with a range of 2-32, caused by the length of the service period per stallion. The average observed and unbiased expected heterozygosity was 0.688 and 0.631, the mean number of alleles was 4.448, and Wright's FIS was -0.173. Pairwise genetic distances (FST and Nei's unbiased genetic distances) were significant and varied between 0.038 to 0.091 and 0.085 to 0.290, respectively. Neighbor-joining dendrogram plots clustered a large proportion of the paternal progeny groups in different branches. Posterior Bayesian analyses using seven paternal half-sib groups with 10-74 members supported a maximum of six clusters, with two paternal progeny groups not differing, and a median of five clusters, with two groups of two sires each falling into the same clusters. When sires were employed in non-consecutive years, progeny from these different years of the same sires were grouped in the same cluster, whereas the progeny of one sire from two consecutive years were in different clusters. We were able to distinguish male progeny from Dülmen wild horse stallions and to show the effects of stallion use on the genetic substructure in the Dülmen wild horse herd. In conclusion, the analyses showed the genetic potential of the Dülmen wild horse stallions to maintain a high genetic diversity and also the effects in which breeding seasons and for how long stallions are used to sire foals. The selection of stallions may be sensitive for the further development of genetic diversity and preserve this closed population as a valuable resource for further studies on the evolution of the horse.

Hypoechoic ultrasonographic findings in the patellar ligaments are common in riding and trotting horses in training (116 cases).

Patellar ligament (PL) injuries are increasingly being reported in horses, but few studies have described the normal PL ultrasonographic appearance in horses. The aims of this prospective observational study were to describe the ultrasonographic appearance of the PLs and infrapatellar fat pad in a population of horses in training and to relate the ultrasonographic findings to objectively measured movement asymmetry. B-mode and color Doppler ultrasonographic examination of the PLs and infrapatellar fat pad in both hind limbs and objective gait analyses were performed on the 116 riding and trotting horses included in the study. The association between ultrasonographic findings, horse age, and movement asymmetry during the trot was then investigated. Distinct or diffuse hypoechoic regions were commonly found in the intermediate PL (24/116; 20.7%), especially in the caudal aspect of the mid-third of the ligament. The infrapatellar fat pad had a hypoechoic striated appearance in all horses except one, in which it was hyperechoic. No association was found between ultrasonographic findings in the PLs and infrapatellar fat pad and lameness. It is important to recognize that there is biological variation in PL appearance, which may or may not be associated with pain in this area, therefore emphasizing the use of local analgesia to determine the location of the lameness.

Rational quinidine dosage regimen for atrial fibrillation in Thoroughbred racehorses based on population pharmacokinetics.

Quinidine (QND) sulfate is an effective treatment for atrial fibrillation (AF) in horses, and several dosage regimens have been proposed to address its wide variability in response and potential adverse effects. The purpose of this study was to analyze the variability in plasma quinidine concentrations using population pharmacokinetics to determine an effective and safe dosage regimen for Thoroughbred horses. Six healthy Thoroughbred horses were treated with 20 mg/kg quinidine sulfate dihydrate (16.58 mg/kg QND base) administered PO or 5 mg/kg quinidine hydrochloride monohydrate (4.28 mg/kg QND base) administered IV (single administration), and blood samples were taken regularly. Four healthy horses were treated with 20 mg/kg quinidine sulfate dihydrate administered twice (every 6 h) via PO route. For the other 19 Thoroughbred racehorses that developed AF, blood samples were taken during quinidine therapy. Quinidine concentrations were measured in all plasma samples using liquid chromatography with tandem mass spectrometry, and the data from 29 horses were modeled using a nonlinear mixed-effects model, followed by Monte Carlo simulations (MCS). The median quinidine concentration for successful sinus rhythm conversion was 2.0 μg/mL (range: 0.5-2.7 μg/mL) in AF horses, while a median concentration of 3.8 μg/mL (range: 1.6-5.1 μg/mL) showed adverse effects. MCS predicted that plasma quinidine concentrations for quinidine sulfate dihydrate PO administration (loading dose: 30 mg/kg, maintenance dose: 6.5 mg/kg q 2 h) reached 1.4, 2.0 and 2.7 μg/mL in 90, 50 and 10% of the horse populations, respectively. Increasing the loading dose to 45 mg/kg and the maintenance dose to 9 mg/kg q 2 h, the plasma concentrations achieved were 1.9, 2.8, and 3.8 μg/mL in 90, 50, and 10% of horse populations, respectively. Using simulations, different empirical dosing regimens were proposed to achieve plasma quinidine concentrations immediately or progressively, representing a tradeoff between optimizing therapeutic effects and minimizing adverse effects. A combination of these dosing regimens is recommended to gradually increase the therapeutic concentration levels of quinidine for safe and effective treatment of AF in racehorses.

Assessment of horse breeding and husbandry practices in southwest Ethiopia: Its implication to design breeding program

Ethiopian horses are multipurpose horses that have socioeconomic significance for smallholder farmers. However, studies regarding their husbandry practices have received little attention. Thus, the current study was conducted to assess the horse husbandry practices in the southwest Ethiopia. Data were collected through semi-structured questionnaires from a total of 196 randomly selected respondents. The general linear model and frequency procedures of the Statistical Analysis System (SAS 9.0) were used to analyze the quantitative and qualitative data, while indices were calculated using Microsoft Excel 2016. Most of the respondents from the Telo district were illiterate, while the percentage of literate farmers was greater in the Gesha and Masha districts. The within-household flock structure and level of importance were dominated by cattle and sheep, followed by horses. The horses were used for transport, draft power, and breeding purposes. In terms of shelters, the horses in the Telo district stayed in shelters, while the horses in the Masha district stayed in forests during both the dry and wet seasons. However, the majority of the horses in the Gesha district were sheltered during the wet season, while they were left to stay in the forest during the dry season. The respondents provided supplementary feed and water to their horses while the water point was located within a kilometer distance. Government and private veterinary shops were the primary sources of veterinary services. Farmers sold their horses at the local market. Castration was performed to minimize aggressiveness. Body size, conformation, and temperament were used as sire selection criteria. An increasing trend in horse population size due to increased farmer interest was observed. In the studied areas, horses were found to be highly important to the livelihood of the farmers. However, horse husbandry practices were led by a considerably greater number of illiterate farmers. Moreover, horse management activities, including the housing of horses, need more attention. Therefore, successive awareness-raising campaigns, including the introduction of formal schooling, are recommended to improve the horse breeding and husbandry practices. Moreover, breeding programs with the aim of genetic improvement and conservation need to be designed to optimize the sustainable utilization of the horses.

Breeding work with kazakh horses Zhabe type

Background and Aim. Kazakh horses of Zhabе type differ from local horses in their higher live weight and larger body measurements. Breeding work with Kazakh horses of the Zhabе type is carried out at Tailak farm in Zharminsky district of East Kazakhstan through targeted reproduction, cultivation, and widespread use of the best individuals based on their origin, exterior, productivity, adaptation to year-round grazing, and quality of offspring from stallions and mares. Individuals that are not up to these standards are strictly culled. The aim of the research is to determine meat productivity and study genetic characteristics of a sample of modern population of Kazakh horses of Zhabe type using DNA markers.Materials and Methods. The material for the study was DNA genotyping data from 20 horses of the Kazakh breed type Zhabe. The horses were genotyped according to 17 STR lоci rеcommended by the Internаtional Sоciety for Animаl Gеnetics (ISАG). The international alphabetical code was used to identify alleles. Genetic and population analyses were performed using the GenAIEx software 6.5. The follоwing indicаtors wеre calculаted: the averаge numbеr of allеles per lоcus (Na), the effеctive numbеr of allеles (Ne), levеls of expеcted (He) and obsеrved heterozygоsity (Ho), and inbreеding cоefficient (FIS) .Results. A study on 17 STR loci of DNA in Kazakh horses Zhabе type has shown that they have a unique allele pool with a significant number of identified alleles and high genetic variability. The average inbreeding coefficient (FIS) is negative (-0.059), indicating that the genetic diversity of this breed is preserved within this group.Conclusion. The improvement of these horses is achieved through breeding and cultivation of animals with high genetic potential for productivity, which is passed down through generations of descendants. This is done by carefully selecting horses with desirable traits for breeding.

Serological monitoring of Influenza A among wild and domestic ungulates in Ukraine

The article provides a brief historical background of equine influenza, the spread of this disease worldwide, and the current epizootic situation. The results of serological monitoring by ELISA of wild and domestic ungulates from different farms and regions of Ukraine for the presence of antibodies to influenza A viruses are presented. Blood serum samples from 372 domestic horses and 32 wild ungulates were tested. Samples from animals collected in 2023 and 2024 and archival blood serum samples from 2021 were used and tested according to the manufacturer’s instructions using ELISA test systems manufactured by IDEXX, INGEZIM, and IDVet. The data obtained indicate a fairly active circulation of influenza A viruses in populations of unvaccinated domestic horses. The circulation was established not only in recent years (2023–2024, seroprevalence from 10% to 100%), but was observed earlier, as evidenced by the detection of 60.9% of positive samples in samples collected in 2021. In addition, two out of three positive samples were found in wild horses from Kherson Region, which indicates the circulation of influenza A virus among wild animals and requires further investigation. The results correlate with the worsening of the epidemiological situation regarding influenza in animals in Europe. The subsequent phase of the research is serotyping, which involves determining the presence of antibodies to specific virus subtypes by hemagglutinin

Clinical variability of equine asthma phenotypes and analysis of diagnostic steps in phenotype differentiation

BackgroundEquine asthma is a common, non-infectious, chronic lung disease that affects up to 80% of the horse population. Strict phenotyping and identification of subclinically asthmatic horses can be challenging. The aim of this study was to describe equine asthma phenotypes (mild, moderate, and severe asthma) defined by BALF cytology and occurrence of clinical signs in a population of privately owned horses and to identify the variables and examination steps with best discriminative potential. The standardised examination protocol included clinical examinations, blood work, airway endoscopy with bronchoalveolar lavage fluid analysis, arterial blood gas analysis and radiography under clinical conditions performed by one veterinarian.ResultsOut of 26 horses, four were diagnosed with mild (subclinical), seven with moderate, and seven with severe asthma based on clinical examination and BALF cytology. Eight horses served as controls. Cough with history of coughing was the strongest variable in phenotype differentiation. Factor analysis revealed an increasing clinical variability with disease severity and an overlapping of clinical presentations between phenotypes. Elevated mast cell (4/4 horses) and neutrophil counts (3/4 horses) in bronchoalveolar lavage cytology differentiated mild asthmatic horses from healthy horses. Moderate and severe asthmatic horses were characterised by clinical signs and neutrophil counts.ConclusionsThe results indicate that medical history, clinical examination and bronchoalveolar lavage cytology are minimum indispensable steps to diagnose equine asthma and that phenotypes are clinically overlapping. A differentiation of three phenotypes without neutrophil and mast cell counts in bronchoalveolar lavage cytology is not sufficient for clinical diagnostics. A comparably exact diagnosis cannot be achieved by relying on alternative examinations used in this study. Screenings of inconspicuous horses with bronchoalveolar lavage can aid in diagnosing subclinically affected animals, however, group size was small, the procedure is invasive and clinical relevance of slightly elevated cells in bronchoalveolar lavage remains unclear. Clinical relevance could not be clarified in this study, since follow-up examinations or lung function testing were not performed.

Rewilded horses in European nature conservation - a genetics, ethics, and welfare perspective.

In recent decades, the integration of horses (Equus ferus) in European rewilding initiatives has gained widespread popularity due to their potential for regulating vegetation and restoring natural ecosystems. However, employing horses in conservation efforts presents important challenges, which we here explore and discuss. These challenges encompass the lack of consensus on key terms inherent to conservation and rewilding, the entrenched culture and strong emotions associated with horses, low genetic diversity and high susceptibility to hereditary diseases in animals under human selection, as well as insufficient consideration for the social behaviour of horses in wild-living populations. In addition, management of wild-living horses involves intricate welfare, ethics and legislative dimensions. Anthropocentric population-control initiatives may be detrimental to horse group structures since they tend to prioritise individual welfare over the health of populations and ecosystems. To overcome these challenges, we provide comprehensive recommendations. These involve a systematic acquisition of genetic information, a focus on genetic diversity rather than breed purity and minimal veterinary intervention in wild-living populations. Further, we advise allowing for natural top-down and bottom-up control - or, if impossible, simulating this by culling or non-lethal removal of horses - instead of using fertility control for population management. We advocate for intensified collaboration between conservation biologists and practitioners and enhanced communication with the general public. Decision-making should be informed by a thorough understanding of the genetic makeup, common health issues and dynamics, and social behaviour in wild-living horse populations. Such a holistic approach is essential to reconcile human emotions associated with horses with the implementation of conservation practices that are not only effective but also sustainable for the long-term viability of functional, biodiverse ecosystems, while rehabilitating the horse as a widespread wild-living species in Europe.

Nineteen years of radiographic screening: Impact of sepsis and evolution of osteochondrosis dissecans prevalence in Walloon sport horses born between 2004 and 2022.

Osteochondrosis dissecans is a particularly common developmental orthopaedic disorder in equines. Among its causes, the hereditary component is no longer a matter of debate, and, for several decades, the various studbooks for sport horses have been selecting stallions in order to limit the prevalence of this condition in the population. However, to our knowledge, no study has evaluated changes in the prevalence of osteochondrosis dissecans over time through longitudinal monitoring of a population of sport horses. The study presented here is part of a large screening programme for developmental orthopaedic pathologies in Wallonia (Belgium) and assessed the presence of these lesions over a period of 19 years in the Walloon sport horse population according to constant and standardised sampling and diagnostic criteria. The effects of breeding conditions and infection in foals were also assessed by means of questionnaires. The results showed no significant change in the prevalence of osteochondrosis dissecans in a population of 1099 individuals born between 2004 and 2022. Furthermore, individuals who had suffered from sepsis during their growing period were very significantly predisposed (p < 0.001) to the development of osteochondrosis dissecans compared to a control group, with respectively 14/21 (67%) and 103/364 (28%) of individuals affected. This study suggests that the selection programmes applied to the population studied are not sufficiently strong or adapted to reduce the prevalence of osteochondrosis dissecans in the population over a period of 19 years. Moreover, this study confirms that foals with sepsis and concurrent osteochondrosis dissecans lesions should not necessarily be excluded from breeding programmes on this basis.

Pinning the tail of the evolution of Streptococcus equi in populations of horses and donkeys

Pinning the tail of the evolution of <i>Streptococcus equi</i> in populations of horses and donkeys

Mating Strategy in the Arab Horse Population Over 30 Years in Algeria

Abstract The objective of this research was to describe the variation in breeding practices in the population of Arabian horses in Algeria in relation to the population size drop observed in the 2000s, due to an increase in the cost of food and a change in interest in racing, related to the black decade. As a result, the breeders had to face two opposite constraints: enhancing reproduction to counter the population decline and preventing the loss of genetic diversity. The aim of the study was to evaluate the genetic consequences of the decisions taken over a period of 30 years, starting from 1988 to 2018. The study was based on the analyses of the stud-book and on 11 microsatellite markers in a group of 943 horses, distributed into 13 age classes. Between 2004 and 2008, the breeders purchased foreign sires and dams, allowing a relative stability in unbiased heterozygosity of about 71%, due to the high genetic distances between foreign and local horses. As these importations stopped from 2009 on, there was a decrease in allele numbers of about 20%. Moreover, from 2010 on, we observe an excess of inbreeding and an increase in genetic drift relative to the starting population, due to population size decline. From the analysis of genetic distances between local individuals, it seems that the only constraint for sires and dams allowed to mate was a null coefficient of inbreeding.

Flow interruption compared to forced oscillatory maneuvers and esophageal balloon/pneumotachography for measurement of respiratory resistance in the horse.

Pulmonary function testing is critical to the diagnosis of equine asthma (EA), an important cause of respiratory disease in the horse, but its clinical use has remained elusive, unfortunately, due to the complexity of reference methods, esophageal balloon/pneumotachography (EBP), and forced oscillatory mechanics (FOM), so we sought a noninvasive, portable method for use in horses through rapid interruption of airflow for equilibration of alveolar pressure with proximal airway pressure, termed flow interruption (FI). Resistance (RINT) was computed as the relationship between the change in pressure at the nose before and immediately after interruption and flow immediately before interruption. A pilot study in five healthy university-owned animals using EBP and FI showed good correspondence between the two methods: RINT (0.33 ± 0.05 cmH2O/L/s) and RL (0.31 ± 0.06 cmH2O/L/s). In two separate populations of client-owned horses, with random assignment of methods to FI versus EBP (n = 8), RINT showed good correlation with RL in horses (rs = 0.995, P = 0.0002) and accords with RL, with no significant difference between RINT and RL. Using FOM (n = 12), RINT (0.67 ± 0.31 cmH2O/L/s) has good correlation with RRS measured with FOM (r = 0.834, P = 0.0001), but is consistently smaller than RRS (0.74 ± 0.33 cmH2O/L/s). Histamine bronchoprovocation (HBP) was performed in a subset of these horses: FI classified one horse in six as less reactive than did EBP, and FI classified one horse in seven as less reactive than did FOM.NEW & NOTEWORTHY We developed and document for the first time the use of flow interruption for the rapid and noninvasive measurement of resistance in equine patients and demonstrated short- and long-term stability and accuracy in comparison with the reference methods.

Multivariate analysis of morphometric traits of the horse ecotypes reared in highlands of Bale Zone, Ethiopia

This study was conducted to evaluate morphometric traits of horse ecotypes reared in four districts of the Bale highlands, southeastern Ethiopia. Twenty-seven morphometric traits were measured from 500 horses (294 males and 206 females) of both sexes. Data were analyzed using SAS 2012. This study revealed that certain traits, such as head length, loin length, bi-ischial width, and sternum height of horses were similar. However, significant differences (p < 0.0001, p < 0.01, p < 0.05) were observed in other traits across the districts. All traits were affected by age (p < 0.05) except rump width and canon perimeter. All 27 morphometric traits were subjected to STEPDISC analysis, of which 21 had the best discriminating power. The uppermost distances of 32.2 and, 28.8 were reported between the Agarfa and Dinsho and, Agarfa and Sinana horse populations, respectively. Mean separation distance among districts ranges from -1.75 to 3.57, -2.42 to 2.43, and -1.61 to 0.92 for CAN1, CAN2 and CAN3, respectively. The quadratic discriminate function classified 95.2, 94.4, 96.0, and 96.8 % of the sampled horses into source populations of the Dinsho, Agarfa, Sinana, and Goba districts, respectively. In addition, the cross-validation summary revealed reduced consistency of membership among each districts with 5 % average success rates and 4, 8, 4, and 4 % for the Dinsho, Agarfa, Sinana, and Goba districts, respectively. Therefore, the presence of variation in morphometric traits within the Bale Highland horse ecotypes has the potential for selection and further genetic interventions.

Međusobni utjecaj reproduktivnog statusa, dobi i osobnosti konja na ostvarivanje punog atletskog potencijala u natjecanjima u preponskom jahanju

The study analysed the results of showjumping competitions of 41 warmblood horses of varying reproductive status, age and personality. In total, 8 stallions, 18 mares, and 15 geldings were included. Horses were divided in the following age groups: young horses 4-7 years old (n=15), mature horses 8-13 years old (n=13) and older horses 14-20 years old (n=13). Horses were also divided according to dominant personality component, obtained by questionnaires: excitability (n=4), protection (n=7), sociability (n=15), curiosity (n=9), horses without a dominant personality component (n=6). Horses in this study were compared to the results of showjumping competitions of the Croatian Equestrian Federation in the past two consecutive years, considering data from 80 classes, 44 tournaments and 3280 starts. The Winter Cup (1.10-1.3) was considered the time of absence of cyclicity in mares while the Summer Cup (1.3-1.10) was considered the full season of reproductive cyclicity of mares. The aim of the study was to determine correlations between the dominant personality component, reproductive status and age of the horse in obtaining optimal results in showjumping competitions. Based on the results, the dominant personality component positively influences the horse’s success in showjumping(ranking, penalties). Excitable horses had the poorest results, especially during the reproductive season (P&amp;lt;0.05). Protective horses had the best results regardless of season. It is likely that determination of the dominantpersonality component could help in better selection of showjumping horses. Geldings had the least seasonal variations, while mares had significantly better results out of season (P&amp;lt;0.05). Stallions also had better results out of season, though the difference was not statistically significant. Recommendations include introducing methods of cycle blockage in mares to improve focus and results in all categories. Contrary to expectations, older horses (14-20 years old) obtained better results than mature horses (8-13 years old). Further research of all observed parameters on a significantly higher sample of showjumpers is required to determine whether the findings here could be applied to the complete population of warmblood horses used in showjumping competitions in Croatia and abroad.

Genetic Diversity and Population Structure of Dülmen Wild, Liebenthal and Polish Konik Horses in Comparison with Przewalski, Sorraia, German Draught and Riding Horses.

The objective of the present study was to analyze the genetic diversity, individual-based assessment of population structure, and admixture in the Dülmen wild horse population in comparison to warmblood, coldblood, and primitive horse populations. The Dülmen wild horse is kept as a unique horse population in the Merfelder Bruch near Dülmen in Westphalia, Germany, and since 1856 has been managed by the Dukes of Croÿ. The Dülmen wild horse population is exposed to the natural conditions of the Merfelder Bruch all year round without human interventions for feeding and veterinary care. In the present study, genetic diversity was estimated for 101 Dülmen wild horses using multilocus genotypic information from a set of 29 autosomal microsatellites and compared with 587 horses from 17 different horse populations. Dülmen wild horses maintained a high degree of genetic diversity, with an average observed heterozygosity of 0.68, a mean number of 6.17 alleles, and heterozygote deficit of -0.035. Pairwise genetic distances (FST, Nei's standard, and Cavalli-Sforza distances) were closest to German coldblood breeds, Polish Konik, and Icelandic horses and most divergent from Sorraia and Przewalski's horses. Neighbor joining dendrogram and PCA plots showed a clear distinction of Dülmen wild horses from other populations, particularly from Przewalski horses. Posterior Bayesian analysis confirmed clear differentiation from other horse populations without an admixture pattern and a high membership index (0.92). It was possible to distinguish Dülmen wild horses from Dülmen and Polish Konik horses. In conclusion, Dülmen wild horses show a notable separation from other German horse breeds and primitive horse populations and may serve as a resource to study evolution of equine domestication.

Prevalence of movement asymmetries in high-performing riding horses perceived as free from lameness and riders' perception of horse sidedness.

A high proportion of horses in training, perceived as free from lameness by their owner, exhibit vertical movement asymmetries. These types of asymmetries are sensitive measures of lameness, but their specificity as indicators of orthopaedic pathology or locomotor function remains unclear. Equine athletes performing at a high level could be assumed to exhibit a higher degree of movement symmetry compared with the general horse population, but this has not been confirmed. This study investigated the prevalence of movement asymmetries in horses performing at a high level in three equestrian disciplines; show jumping, dressage and eventing, as well as the association between riders' perception of horse sidedness and said movement asymmetries. Using an inertial measurement unit-based system (Equinosis), gait analysis was performed on 123 high-performing horses. The mean difference between the two vertical minimum and between the two maximum values of each stride was recorded for the head (HDmin, HDmax) and pelvis (PDmin, PDmax). The horses were defined as asymmetric if one or multiple asymmetry parameters exceeded an absolute trial mean of: >6mm for HDmin or HDmax, and >3mm for PDmin or PDmax, with standard deviation less than the respective mean value. Based on the results, 70% of the horses were classified as asymmetric, which is similar to previous findings for young riding horses and horses competing at a lower level. More than one-third of these high-performing horses had asymmetry values of similar magnitude to those seen in clinically lame horses. No clear associations were observed between rider-perceived sidedness and the vertical movement asymmetry values, indicating that the perceived unevenness between sides is not a determinant of vertical movement asymmetry. Longitudinal studies on movement asymmetries in relation to training intensity and full clinical examinations with local or systemic analgesic testing are desired as further research to determine whether these movement asymmetries indicate a welfare problem.

Seroprevalence of Toxoplasma gondii and Neospora spp. in horse population of Tehran, Iran

Neospora spp. and Toxoplasma gondii are two closely related protozoan parasites that are widely distributed throughout the world. Horses can act as intermediate hosts for both parasites and can acquire disease. Blood samples were taken from 487 clinically healthy horses from 17 different mechanized stables in Tehran, the capital of Iran, during September and November of 2022. IFAT and ELISA were employed to detect antibodies directed against Neospora spp. and T. gondii. The anti-N. caninum antibodies were detected in 52 of the horses (10.67%) based on IFAT and in 86 of the 487 horses (17.65%) based on the ELISA test. Also, antibodies against T. gondii were detected in 41 horses (8.42%) based on IFAT and in 63 of 487 horses (12.94%) based on the ELISA test. Also, in 6 of the horses (1.23%) based on IFAT and in 13 of the 487 horses (2.67%) based on the ELISA test, double positivity suggested co-infection with both parasites. Gender, age groups, and the presence of dogs for neosporosis, and age groups and the presence of cats for toxoplasmosis, could be considered factors having an influence on the seroprevalences (P < 0.05). The results proved the importance of the urgent implementation of stringent regulatory measures to prevent and control the spread of these parasites.