Horse Breeds Research Articles

Intracytoplasmic sperm injection zone: insights and applications from a university-based assisted reproduction laboratory

Intracytoplasmic sperm injection (ICSI) has become one of the most important tools used for in vitro production of embryos (IVP) in equine reproduction management programs around the world. This procedure is often performed in the US for several breeds and is used primarily to optimize foal production for broodmares and performance mares but also for stallions with limited semen availability or poor semen quality. As such, there are a limited number of US laboratories capable of using this method, which requires advanced training of personnel and specialized equipment. Many veterinarians and breeding farms currently aspirate ovarian follicles in cycling mares and ship oocytes to ICSI-capable laboratories, where embryos can be produced and typically vitrified for ultralow temperature storage and transport for transfer to recipient mares and establishment of surrogate pregnancies. The Veterinary Assisted Reproduction Laboratory in the School of Veterinary Medicine at the University of California, Davis, maintains a 3-dimensional approach to equine assisted reproductive technology. We offer commercial solutions to breeders, educational advice and training to other laboratories, veterinarians, and visiting scholars. Moreover, as a research laboratory, our objective is to analyze and apply observations from IVP to elucidation of complex developmental problems such as embryonic and fetal loss. In 2018, we reported the birth of the first foal produced at UC Davis using ICSI, and we have since developed a commercial ICSI program for practitioners and horse breeders in the US. Today, our laboratory receives thousands of immature oocytes for ICSI sessions every year, with an average of 2 embryos per mare-session. Our research is focused on molecular, cellular and genetic aspects of gamete biology, perifertilization events, and early equine development using an array of tools including advanced microscopy, sequencing, and time-lapse imaging of developing embryos. In this review, we have highlighted our laboratory’s current methods for commercial equine IVP and research and clinical studies conducted to optimize IVP in horses.

Assessing the Peripheral Levels of the Neurotransmitters Noradrenaline, Dopamine and Serotonin and the Oxidant/Antioxidant Equilibrium in Circus Horses.

Due to the paucity of information on circus management effects on the welfare of horses, this study investigated the plasma concentrations of noradrenaline, dopamine and serotonin, known to be indices of mental status, as well as the reactive oxygen metabolites (d-Roms) and the biological antioxidant potential (BAP), likely to denote the oxidant/antioxidant equilibrium of organisms, in horses managed in different Italian circuses. For the study, 56 circus horses of different breeds and ages were enrolled and divided into six groups according to the horses' management (circus management, groups G1-G5; classic riding management representing the control group, CG). From each horse, blood samples were collected in order to assess the concentration of selected parameters. One-way ANOVA showed no differences (p > 0.05) in serotonin, dopamine, noradrenaline, d-Roms and BAP values between circus and control horses. No differences related to the breed of the horses enrolled in the study were found in the values of all investigated parameters (p > 0.05). Furthermore, neurotransmitters showed overlapping levels between the different age classes of investigated horses (p > 0.05); contrariwise, the age of the horse displayed a significant effect on BAP values, with the oldest horses (16-21 age class) exhibiting lower BAP values compared to 4-5, 6-10 and 11-15 age classes (p < 0.05), whereas the d-Roms showed similar values in horses of different age classes (p > 0.05). The results gathered in the present study suggest that the mental status of horses under circus management was not compromised; however, better attention and care in the management of older horses is advocated, as they showed a lower biological antioxidant potential than younger horses; thus, they could be more susceptible to oxidative stress.

Assessment of fetal development during mid and late term pregnancies by standard B-Mode ultrasonography in Shetland ponies

Transrectal and transabdominal ultrasonography is an established method to monitor pregnancy, fetal growth and wellbeing in different species. Growth charts with multiple bio-morphometric parameters to estimate days of gestation and days before parturition exist in small companion animals, sheep and goats, riding type horses and large ponies but not in small horse breeds like Shetland ponies. The aim of this study was to apply fetal biometric assessment and detailed description of physiologic fetal development to mid and late term pregnancies in Shetland mares and to generate reference data for clinical practice and for future research. Fetal parameters were collected starting on day 101 of pregnancy in five Shetland mares. The fetal biometric parameters determined consisted of aortic diameter, eye diameter, combined rib and intercostal distance (CRID), stomach length and width and different heart morphology parameters in sagittal and frontal plane. Additionally, fetal activity and organ development in terms of differentiation and changes in echogenicity were recorded. Considering reliably assessable parameters, fetal CRID was the best predictor for gestational age with ± 13.6 days and fetal aortic diameter the most accurate for prediction of days until parturition with ± 16.2 days.

Genetic diversity and signatures of selection in Icelandic horses and Exmoor ponies

BackgroundThe Icelandic horse and Exmoor pony are ancient, native breeds, adapted to harsh environmental conditions and they have both undergone severe historic bottlenecks. However, in modern days, the selection pressures on these breeds differ substantially. The aim of this study was to assess genetic diversity in both breeds through expected (HE) and observed heterozygosity (HO) and effective population size (Ne). Furthermore, we aimed to identify runs of homozygosity (ROH) to estimate and compare genomic inbreeding and signatures of selection in the breeds.ResultsHO was estimated at 0.34 and 0.33 in the Icelandic horse and Exmoor pony, respectively, aligning closely with HE of 0.34 for both breeds. Based on genomic data, the Ne for the last generation was calculated to be 125 individuals for Icelandic horses and 42 for Exmoor ponies. Genomic inbreeding coefficient (FROH) ranged from 0.08 to 0.20 for the Icelandic horse and 0.12 to 0.27 for the Exmoor pony, with the majority of inbreeding attributed to short ROHs in both breeds. Several ROH islands associated with performance were identified in the Icelandic horse, featuring target genes such as DMRT3, DOCK8, EDNRB, SLAIN1, and NEURL1. Shared ROH islands between both breeds were linked to metabolic processes (FOXO1), body size, and the immune system (CYRIB), while private ROH islands in Exmoor ponies were associated with coat colours (ASIP, TBX3, OCA2), immune system (LYG1, LYG2), and fertility (TEX14, SPO11, ADAM20).ConclusionsEvaluations of genetic diversity and inbreeding reveal insights into the evolutionary trajectories of both breeds, highlighting the consequences of population bottlenecks. While the genetic diversity in the Icelandic horse is acceptable, a critically low genetic diversity was estimated for the Exmoor pony, which requires further validation. Identified signatures of selection highlight the differences in the use of the two breeds as well as their adaptive trait similarities. The results provide insight into genomic regions under selection pressure in a gaited performance horse breed and various adaptive traits in small-sized native horse breeds. This understanding contributes to preserving genetic diversity and population health in these equine populations.

Saliva and plasma metabolome changes during anoestrus, the oestrous cycle and early gestation in the mare: A pilot study

Successful reproductive management of domestic mammals depends primarily upon timely identification of oestrous cycle stages. There is a need to develop an alternative non-invasive, welfare-friendly, accurate and reliable method to identify reproductive cycle stages. This is of particular interest for horse breeders, because horses are high-value farm animals that require careful management and individual monitoring. Saliva sampling is non-invasive, painless and welfare-friendly. Thus, we performed a metabolomic analysis of equine saliva during different reproductive stages to identify changes in the salivary metabolome during anoestrus, the oestrous cycle and early gestation. We compared the saliva and plasma metabolomes to investigate the relationship between the two fluids according to the physiological stage. We collected saliva and plasma samples from six mares during seasonal anoestrus, during the follicular phase 3 days, 2 days and 1 day before ovulation and the day when ovulation was detected, during the luteal phase 6 days after ovulation, and during early gestation 18 days after ovulation and insemination. Metabolome analysis was performed by proton-nuclear magnetic resonance spectroscopy. We identified 58 and 51 metabolites in saliva and plasma, respectively. The levels of four metabolites or groups of metabolites in saliva and five metabolites or groups of metabolites in plasma showed significant modifications during the 4 days until ovulation, ie 3 days prior to and on the day of ovulation. The levels of 11 metabolites or groups of metabolites in saliva and 17 metabolites or groups of metabolites in plasma were significantly different between the seasonal anoestrus and the ovarian cyclicity period. The physiological mechanisms involved in the onset of ovarian cyclicity and in ovulation induced modifications of the metabolome both in plasma and saliva. The metabolites whose salivary levels changed during the reproductive cycle could be potential salivary biomarkers to detect the reproductive stage in a welfare friendly production system. In particular, we propose creatine and alanine as candidate salivary biomarkers of ovulation and of the onset of ovarian cyclicity, respectively. However, extensive validation of their reliability is required. Our study contributes to extend to domestic mammals the use of saliva as a non-invasive alternative diagnostic fluid for reproduction in a welfare-friendly production system.

BREEDING ACHIEVEMENTS OF UKRAINE (PAST, PRESENT): BREEDS, TYPES AND LINES OF AGRICULTURAL ANIMALS

The purpose of the study was to establish chronologically breeding achievements in livestock breeding of Ukraine with the help of the relevant Register. To analyze the dynamics of the number of breeding animals, the State Register of Breeding Subjects in Livestock Breeding for the period 2002 ... 2022 was used. The genealogical structure of the six studied breeds of dairy cattle includes 10 interbreed and 11 local types, 47 local and 38 genealogical lines and about 244 families. Beef cattle are represented by four approved breeds, 4 interbreed and 2 local types, 32 lines and 172 families. The pedigree pig breeding of Ukraine includes seven domestic breeds with three interbreed types, 11 local types, 95 lines and 159 families. In the fields of sheep breeding and horse breeding, five and two breeds were created, respectively, and their genealogical structure was formed from 11 interbreed types and 28 families in sheep breeding and 15 lineages and related groups and 25 families in horse breeding. One breed and two crosses (10 lines) of laying hens, one cross (two lines and eight microlines) of turkeys and four breed groups of ducks represent poultry breeding.

GENETIC PARAMETERS D-SYSTEMS OF BLOOD TYPE IN MARES OF NOVOОLEKSANDRIVSKA HEAVY AND TORI BREEDS

The article presents the results of studies of the immunogenetic structure of mares of the novoоleksandrivska and tory breeds of horses of different farms of Ukraine according to the D-system of blood groups. A comparative analysis of these breeds was carried out, taking into account the fact that the novoоleksandrivska is a weight-carrying breed, and in the Tory breed we singled out only the heavy type. That is, our goal was to find common or different features in their immunogenetic profiles. The population of mares of the novoоleksandrivska heavy breed is characterized by a high frequency of alleles: Ddg (0.225), Dad (0.183), Dd (0.167). Dde (0,162), Dcgm (0,142). The Dbcm (0.039), Dcegm (0.035), and Ddk (0.015) alleles were relatively less frequently detected. Thorians have a high frequency of alleles: Dcgm (0.326), Ddk (0.260), Dd (0.138) Ddg (0.10). The Dde (0.08), Dbcm (0.042), Dcegm (0.020), and Dad (0.014) alleles are less common. The rarest allele in the novoоleksandrivska heavy truck is Ddk (0.015), which is 6.67% less common than Ddg (0.225). Thus, the level of genetic diversity in all studied breeds is at a high level, which indicates a significant reserve of variability and creates the basis for further selection and breeding work. A comparative characterization of the novoоleksandrivska and tory breeds was carried out and it was established that the frequency of occurrence of Dad and Ddg alleles in the novoоleksandrivska heavy hauler is higher than the average for the breed. At the same time, Dсgm and Ddk alleles predominate in the heavy type of the tory breed, which is characteristic of each breed and can serve as a kind of "genetic passport".

Effect of Age on the Biochemical and Hematological Blood Profile in the Arabian Horses Raised in Libya

Normal hematological and biochemical values need to be defined for each equine age in order to increase diagnostic precision. The present study was aimed to monitor the hematobiochemical characteristics of 65 clinically healthy Arabian horses raised in Libya with an age of less than or equal 3 years (young) or more than 3 years (stallion). The results showed that MCHC were significantly (p&lt;0.0001) higher in the young horses than stallions, while the reverse for HCT, MCV, RDW-CV, RDW-SD, and MPV. On the other hand, Hb, RBC, MCH, PDW and PCT showed non-significant change with the variations between Arabian horse's ages. The total leukocyte and platelet counts were statistically increased in young horses but did not significantly different. Regarding activities of different enzymes (ALT, AST, ALP and LDH activity), there are significantly (p&lt;0.05) increased values in young horses compared with stallions. However, the serum TP, TB and DB were significantly (p&lt;0.005) higher in adult horses than young one. There are significant and non-significant differences in some lipid profile and electrolytes between animals according to age factor. In abbreviate, results of this study showed that both blood and biochemical parameters clearly alterated under the effect of age in this breed of horses.

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.

Methodological approaches to assessing the genetic predisposition of osteochondrosis of the tarsocrural joint in the Pura Raza Española horses

Osteochondrosis (OC) is a developmental orthopaedic disease of significant concern in numerous sport horse breeds, with significant international relevance. Using digital radiographs, we assessed the occurrence of hock (tarsocrural joint) OC in 3 048 Pura Raza Española (PRE) horses which took part in a morpho-functional test, in three specific locations in the tarsus limbs: the Distal Intermediate Ridge of the Tibia (DIRT), the lateral trochlear ridges of the talus (LTT), and the medial trochlear ridges of the talus (MTT). An incidence rate of 13.3% was found for hock OC in the analysed sample, with the highest incidence rate observed in DIRT (10.0%) and the lowest in MTT (0.2%). Estimates of genetic predisposition to hock OC were carried out using three genetic approaches: 1a) a binomial threshold model based on the presence or absence of OC, 1b) a multinomial threshold model, on a scale from 0 (absence) to 3 (maximum), and 2) a linear model. The effects considered in the models included sex, genetic origin and stud class. All the analyses were based on the Bayesian inference methodology, using the THRGIBBS3F90 software. The binomial threshold model yielded the most suitable results, with an estimated heritability for Overall hock OC of 0.71 ± 0.055 on the underlying scale (0.53 on the observed scale), ranging in different locations from 0.48 ± 0.087 (LTT) to 0.66 ± 0.063 (DIRT) on the underlying scale (0.10 and 0.38 on the observed scale, respectively). The highest significative genetic correlation was observed between Overall and DIRT (0.97) for approach 1a, and the lowest significant genetic correlation was between Overall and LTT (0.49), for approach 2. This study contributes valuable insights into the genetic predisposition towards, as well as for the potential for selective breeding against, hock OC in PRE horses, and provides a basis for future research and breeding programmes aimed at minimising the occurrence of hock OC and promoting the overall health of this breed.

Assessment of the genetic similarity between the novoaltayskaya horse breed and the original breeds by microsatellite DNA loci

The research was carried out for the purpose of a comparative assessment of the allele pool of the Novoaltayskaya horse breed and the breeds that participated in its creation. The experimental sample included 5736 horses, including: Novoaltayskaya breed – 363, Altai – 39, Lithuanian Heavy Draft – 159, Russian Heavy Draft – 617, Soviet d Heavy Draft – 288, Orlov trotter – 4,177, Budenny – 93. Population genetic analysis was performed using generally accepted methods. The following indicators were determined: the total number of alleles at 17 loci, the average number of alleles per locus, the level of polymorphism, observed and expected heterozygosity, coefficients of intrapopulation inbreeding, genetic similarity and genetic distances. It was established that horses of the Novo-Altai breed had the highest level of genetic diversity (154 alleles) and polymorphism (Ae = 4,909). Analysis of genetic differentiation showed the absence of intrapopulation inbreeding in the groups of Altai, Lithuanian Heavy Draft and Budenny breeds. Groups of horses of the Novoaltayskaya, Orlov trotter, Russian Heavy Draft and Soviet Heavy Draft breeds were distinguished by a slight deficiency of heterozygotes. It has been established that horses of the Novoaltayskaya and Heavy Draft breeds are characterized by a high frequency of occurrence of the HTG6 O allele, and the Altai breed is characterized by a high frequency of occurrence of the HTG4 M allele. A number of loci of alleles identical in spectrum to those of the Altai, Russian Heavy Draft and Soviet Heavy Draft breeds were identified in the Novoaltayskaya horse. Cluster analysis demonstrated a high level of genetic similarity of horses of the Novoaltayskaya breed with the Russian Heavy Draft (0,903) and Altai (0,899) breeds. As part of the study, using molecular genetic markers, new data was obtained on horses of seven breeds, with the help of which it is possible to improve breeding programs in horse breeding, allowing to control the biodiversity and genetic similarity of populations, preserving the originality and heterogeneity of the allele pool of horses of different breeds.

Using high-density SNP data to unravel the origin of the Franches-Montagnes horse breed

BackgroundThe Franches-Montagnes (FM) is the last native horse breed of Switzerland, established at the end of the 19th century by cross-breeding local mares with Anglo-Norman stallions. We collected high-density SNP genotype data (Axiom™ 670 K Equine genotyping array) from 522 FM horses, including 44 old-type horses (OF), 514 European Warmblood horses (WB) from Sweden and Switzerland (including a stallion used for cross-breeding in 1990), 136 purebred Arabians (AR), 32 Shagya Arabians (SA), and 64 Thoroughbred (TB) horses, as introgressed WB stallions showed TB origin in their pedigrees. The aim of the study was to ascertain fine-scale population structures of the FM breed, including estimation of individual admixture levels and genomic inbreeding (FROH) by means of Runs of Homozygosity.ResultsTo assess fine-scale population structures within the FM breed, we applied a three-step approach, which combined admixture, genetic contribution, and FROH of individuals into a high-resolution network visualization. Based on this approach, we were able to demonstrate that population substructures, as detected by model-based clustering, can be either associated with a different genetic origin or with the progeny of most influential sires. Within the FM breed, admixed horses explained most of the genetic variance of the current breeding population, while OF horses only accounted for a small proportion of the variance. Furthermore, we illustrated that FM horses showed high TB admixture levels and we identified inconsistencies in the origin of FM horses descending from the Arabian stallion Doktryner. With the exception of WB, FM horses were less inbred compared to the other breeds. However, the relatively few but long ROH segments suggested diversity loss in both FM subpopulations. Genes located in FM- and OF-specific ROH islands had known functions involved in conformation and behaviour, two traits that are highly valued by breeders.ConclusionsThe FM remains the last native Swiss breed, clearly distinguishable from other historically introgressed breeds, but it suffered bottlenecks due to intensive selection of stallions, restrictive mating choices based on arbitrary definitions of pure breeding, and selection of rare coat colours. To preserve the genetic diversity of FM horses, future conservation managements strategies should involve a well-balanced selection of stallions (e.g., by integrating OF stallions in the FM breeding population) and avoid selection for rare coat colours.

DNA Methylation and Its Effects on TRIM29 Gene Expression in the Equine Sarcoid Tissue.

Sarcoids are the most frequently diagnosed dermatological tumour in horses. It is a disease that can affect various species of equids, such as donkeys, mules and zebras. This type of tumour can develop in all horse breeds, regardless of age and gender. Treatment options depend on many factors, such as the type of lesion, location, extent, owner preference and financial considerations. In the present study, we investigated the TRIM29 expression, the methylation status of its first exon and its involvement in the formation of equine sarcoids. Bisulfite sequencing PCR (BSP) was used to determine DNA methylation at CpG sites and real-time quantitative polymerase chain reaction (qPCR) was used to detect TRIM29 expression level. Our results showed that TRIM29 is significantly downregulated in lesional samples (FC = -3.72; p < 0.001). Furthermore, TRIM29 expression was significantly correlated (R = -0.73; p < 0.001) with hypermethylation of its specific CpG sites in the first exon of this gene. Our research has demonstrated that the identification of increased methylation of CpG sequences in horse sarcoids, along with the decreased expression of the TRIM29 gene, is an important step towards understanding the molecular mechanisms underlying the disease. These findings can serve in the future as a diagnostic biomarker for horse sarcoids and help in detecting the disease.

The new methodoly of performance testing for young horses of sport breeds

The new methodoly of performance testing for young horses of sport breeds

ORGANIZATION AND ANALYSIS OF PRODUCTION EFFICIENCY HORSE BREEDING PRODUCTS BY BREED AND REGION OF THE REPUBLIC OF KAZAKHSTAN

The system of remuneration for workers in productive horse breeding currently provides for a direct relationship between the level of wages and the quality of the products obtained. In the context of the practical implementation of on-farm self-accounting in herd horse breeding, the form of an annual self-accounting task has proven itself well. In the near future, as the current economic situation changes and a stable demand for high-quality, environmentally friendly horse meat emerges, highly productive horse genotypes, preserved and propagated in breeding farms in various regions, will find wide application, both in purebred breeding and for use in various crossbreeding options.

Insight into the genetic diversity of Selle Français horse populations based on whole D-loop sequencing of mitochondrial DNA

The Selle Français (SF) breed originated from native France horses crossed with Thoroughbreds, Arabs, Anglo-Arabs and French Trotters, which allowed for individuals to be obtained with excellent predispositions and a versatile usage for equestrian sports. The performance of the SF horse is widely accepted in the fields of show jumping and eventing; however, they have successfully started to compete in other areas such as dressage, vaulting, carriage driving and TREC competitions. To date, information about the genetic structure of the SF breed has been very limited. In the present report, Sanger sequencing was applied to analyse the whole D-loop of mitochondrial DNA of 98 samples representing Selle Français horses originating from two populations: Algerian (n=47) and French (n=51). The result obtained showed the presence of 19 SNPs, which allowed us to divide the samples into 41 haplotypes (OR909723‐OR909773). A higher number of haplotypes was detected in the Algerian population (n=24) compared to the French population (n=14), but both populations did not represent unique clusters and showed a high degree of genetic similarities. The result showed that the identified haplotypes of the SF belonged to four clades: L, A, B and G. The present report gives strong evidence that the Selle Français breed has been established based on a great influence of the Thoroughbred, whose close connection is more visible in the French population. The haplogroup assignment to L clades proved that the SF breed has European origin as ancestral haplogroup L was assigned to West and South Europe while A to West Asia and G and B to Middle East. Our results show SF as an example of a contemporary breed of sport horses with European roots further influenced by local breeds.

A Measurement Method for Body Parameters of Mongolian Horses Based on Deep Learning and Machine Vision

The traditional manual methods for measuring Mongolian horse body parameters are not very safe, have low levels of automation, and cannot effectively ensure animal welfare. This research proposes a method for extracting target Mongolian horse body parameters based on deep learning and machine vision technology. Firstly, Swin Transformer is used as the backbone feature extraction network of Mask R-CNN model, and the CNN-based differentiated feature clustering model is added to minimize the loss of similarity and spatial continuity between pixels, thereby improving the robustness of the model while reducing error pixels and optimizing the rough mask boundary output. Secondly, an improved Harris algorithm and a polynomial fitting method based on contour curves are applied to determine the positions of various measurement points on the horse mask and calculate various body parameters. The accuracy of the proposed method was tested using 20 Mongolian horses. The experimental results show that compared with the original Mask R-CNN network, the PA (pixel accuracy) and MIoU (mean intersection over union) of the optimized model results increased from 91.46% and 84.72% to 98.72% and 95.36%, respectively. The average relative errors of shoulder height, withers height, chest depth, body length, croup height, shoulder angle, and croup angle were 4.01%, 2.98%, 4.86%, 2.97%, 3.06%, 4.91%, and 5.21%, respectively. The research results can provide technical support for assessing body parameters related to the performance of horses under natural conditions, which is of great significance for improving the refinement and welfare of Mongolian horse breeding techniques.

Effects of Breed on the Morphometric Parameters of Erythrocytes in Horses

Various factors have a distinct impact on the quantity and dimensions of red blood cells across diverse animal species. These factors encompass age, sex, elevation, time of year, and lineage. The present study aimed to evaluate the influence of breed on the morphometric parameters of red blood cells in horses. To examine the impact of various horse breeds on the diameter, circumference, and surface area of red blood cells, blood samples were obtained from a total of 90 healthy horses. These horses belonged to three different breeds, including Arab Thoroughbred, English Thoroughbred, and Barbe. Each breed consisted of 30 individuals, with an equal distribution of males and females. The collected blood specimens were then divided into two separate batches for further analysis. The age range of all horses included in the study was between 5 and 12 years old. Smears were made and stained using the May-Grünwald Giemsa technique. The morphometric measurements were performed while using the OPTIKATM Vision Pro special software. The obtained results showed that there were no significant differences in the red blood cell diameters across different horse breeds. However, this factor appears to influence significantly both the circumference and surface area of erythrocytes. Specifically, the circumference and surface of Barbe red blood cells were highly smaller than both Arabian and English purebred horses. The present study demonstrated that the circumference and surface of red blood cells appear to be more indicative and representative in detecting variations in the erythrocyte morphometry between different horse breeds.

Impact of the COVID-19 Pandemic on Racehorse Breeders

In this study, a face-to-face survey study was conducted with 58 racehorse breeders and business owners located in Adana, Ankara, Mersin and Sanliurfa provinces about racehorsing during the pandemic period. The study data were analyzed and evaluated with the SPSS 22.0 program. According to the results, according to the gender, horse breeding is largely carried out by men, participants have the most high school graduates as an education level, the average age is 38.6, and they have experienced the most financial losses during the pandemic period, the reason for which is the inability to hold competitions. When these results of breeders are evaluated, it is suggested that it would be beneficial for them to be evaluated regionally in a sub-branch of the ministry and to provide informative trainings for horsemanship in cooperation with the university, the ministry and TJK.

Equine coital exanthema – Eradicated or underdiagnosed disease?

SummaryEquine coital exanthema (ECE) is a contagious, sexually transmitted disease affecting horses. It manifests itself as painful papules, vesicles, pustules and ulcers on the external genitalia in both mares and stallions. While widespread, the disease is generally not classified as reportable in most countries and is not considered a significant threat to the equine industry. ECE is endemic in horse breeding populations internationally. The absence of comprehensive epidemiological data can give a false sense of security, which increases the risk of local transmission. Lack of surveillance programmes or routine control in risk group (reproductive stallions and mares) leads to unawareness and lack of proper biosecurity measures. An outbreak in breeding facilities may result in significant economic consequences. Although ECE has not been officially confirmed in Poland, equine practitioners have noted isolated clinical cases resembling the disease in farm horses in the last decades. This study aims to confirm the presence of ECE in Poland. Clinical diagnosis has been made based on characteristic lesions. Positive diagnosis was confirmed in two out of four outbreaks by real‐time PCR on genital swabs. The presence of the disease has been confirmed in different regions in Poland in farm horses bred as meat animals. Confirming EHV‐3 infection in the Polish equine population through laboratory examinations marks a significant milestone. It is now crucial to raise awareness among owners, breeders and equine practitioners about the current epidemiological status of the disease.