Horse breeds represent the diverse genetic and phenotypic variations found within the species Equus ferus caballus. These breeds are categorized based on characteristics such as size, conformation, coat color, and temperament, which have been selectively bred over centuries to fulfill specific roles and functions. Common classifications of horse breeds include light horses, draft horses, and ponies, each serving different purposes ranging from riding and racing to work and companionship. This page aggregates peer-reviewed research studies and scholarly articles that explore the genetics, history, and functional attributes of various horse breeds, as well as their impact on equine management and breeding practices.
Cosgrove EJ, Sadeghi R, Schlamp F, Holl HM, Moradi-Shahrbabak M, Miraei-Ashtiani SR, Abdalla S, Shykind B, Troedsson M, Stefaniuk-Szmukier M....The Arabian horse, one of the world's oldest breeds of any domesticated animal, is characterized by natural beauty, graceful movement, athletic endurance, and, as a result of its development in the arid Middle East, the ability to thrive in a hot, dry environment. Here we studied 378 Arabian horses from 12 countries using equine single nucleotide polymorphism (SNP) arrays and whole-genome re-sequencing to examine hypotheses about genomic diversity, population structure, and the relationship of the Arabian to other horse breeds. We identified a high degree of genetic variation and complex ances...
Gautier C, Scarlet D, Ertl R, Walter I, Wulf M, Nagel C, Aurich J, Aurich C.The aim of the present study was to characterise key enzymes involved in polyunsaturated fatty acid (PUFA) synthesis in the testis and epididymis collected from 2-year-old healthy warmblood stallions (n=10). The mRNA expression of fatty acid synthase, the Δ9-, Δ6-, Δ5- and Δ4-desaturases and elongases 6, 5 and 2 (encoded by the fatty acid synthase (FASN), the stearoyl-CoA desaturase (SCD), the fatty acid desaturase 2 (FADS2), the fatty acid desaturase 1 (FADS1), the delta 4-desaturase, sphingolipid 1 (DEGS1), ELOVL fatty acid elongase 6(ELOVL6), ELOVL fatty acid elongase 5 (ELOVL5), ELOVL ...
Campolo A, Frantz MW, de Laat MA, Hartson SD, Furr MO, Lacombe VA.Endocrinopathic laminitis is pathologically similar to the multi-organ dysfunction and peripheral neuropathy found in human patients with metabolic syndrome. Similarly, endocrinopathic laminitis has been shown to partially result from vascular dysfunction. However, despite extensive research, the pathogenesis of this disease is not well elucidated and laminitis remains without an effective treatment. Here, we sought to identify novel proteins and pathways underlying the development of equine endocrinopathic laminitis. Healthy Standardbred horses ( = 4/group) were either given an electrolyte in...
Giontella A, Sarti FM, Cardinali I, Giovannini S, Cherchi R, Lancioni H, Silvestrelli M, Pieramati C.The Sardinian Anglo Arab (SAA) is a famous horse breed in Italy, with a significant historical background in the island of Sardinia. The aim of the study is to perform an evaluation of genetic variability in SAA using pedigree and mitochondrial data. In the current population, pedigree completeness was observed to be close to 100%, while the inbreeding coefficient and the average relatedness were lower than 3%. The ratio of effective founders/numbers of ancestors was 3.68 for the whole pedigree. The effective population size (N) computed by an individual increase in inbreeding (N) was 456.86, ...
Raudsepp T.Reproductive disorders are genetically heterogeneous and complex; available genetic tests are limited to chromosome analysis and 1 susceptibility gene. Cytogenetic analysis should be the first test to confirm or rule out chromosomal aberrations. No causative genes/mutations are known. The only available genetic test for stallion subfertility is based on a susceptibility gene FKBP6. The ongoing progress in equine genomics will improve the status of genetic testing. However, because subfertile phenotypes do not facilitate collection of large numbers of samples or pedigrees, and clinical causes o...
Wickens C, Brooks SA.Behavior is a valuable quantitative trait in the horse because of its impact on performance, work, recreation, and prerequisite close interactions with humans. This article reviews what is known about the genetics of behavior in horses with an emphasis on the genetic basis for temperament traits, neuroendocrine function, and stereotypic behavior. The importance of using modern molecular genetic techniques to the study of equine behavior and recommendations for future research are also discussed. Ultimately, these studies enhance the understanding of the biology of behavior in the horse, improv...
Schaefer RJ, McCue ME.High-quality genomic tools have been integral in understanding genomic architecture and function in the modern-day horse. The equine genetics community has a long tradition of pooling resources to develop genomic tools. Since the equine genome was sequenced in 2006, several iterations of high throughput genotyping arrays have been developed and released, enabling rapid and cost-effective genotyping. This review highlights the design considerations of each iteration, focusing on data available during development and outlining considerations in selecting the genetic variants included on each arr...
Fousse SL, Stern JA.There have been some advances in understanding the genetic contribution to ventricular septal defects in Arabians, sudden death in racehorses, and atrial fibrillation in racehorses. No genetic analyses have been published for aortic rupture in Friesians or atrioventricular block in donkeys despite strong evidence for a genetic cause. To date, no genetic mutation has been identified for any equid cardiac disease. With the advancement of genetic tools and resources, we are moving closer to discoveries that may explain the heritable basis of inherited equid cardiac disease.
Ablondi M, Dadousis C, Vasini M, Eriksson S, Mikko S, Sabbioni A.Horses are nowadays mainly used for sport and leisure activities, and several local breeds, traditionally used in agriculture, have been exposed to a dramatic loss in population size and genetic diversity. The loss of genetic diversity negatively impacts individual fitness and reduces the potential long-term survivability of a breed. Recent advances in molecular biology and bioinformatics have allowed researchers to explore biodiversity one step further. This study aimed to evaluate the loss of genetic variability and identify genomic regions under selection pressure in the Bardigiano breed ba...
Varona L, Legarra A.(1) Background: Ranking traits are used commonly for breeding purposes in several equine populations; however, implementation is complex, because the position of a horse in a competition event is discontinuous and is influenced by the performance of its competitors. One approach to overcoming these limitations is to assume an underlying Gaussian liability that represents a horse's performance and dictates the observed classification in a competition event. That approach can be implemented using Montecarlo Markov Chain (McMC) techniques with a procedure known as the Thurstonian model. (2) Metho...
Albrizio M, Lacalandra GM, Volpe S, Nicassio M, Cinone M.Heat Shock Proteins are chaperones primary involved in the repair of cellular damages induced by temperature. The harmful effect of temperature on the male gonad is well known, on the contrary knowledge on the effects of the environment on semen quality are still insufficient. The aim of this paper was to learn more about the role of HSPs and the environment in modulating the physiology of equine male gonads. We showed a detailed analysis of equine semen characteristic and the expression level of three HSPs (60-70-90) over a one-year period analyzing the effects of temperature and humidity and...
Corbin LJ, Pope J, Sanson J, Antczak DF, Miller D, Sadeghi R, Brooks SA.Novel coat colour phenotypes often emerge during domestication, and there is strong evidence of genetic selection for the two main genes that control base coat colour in horses- and . These genes direct the type of pigment produced, red pheomelanin () or black eumelanin (), as well as the relative concentration and the temporal-spatial distribution of melanin pigment deposits in the skin and hair coat. Here, we describe a genome-wide association study (GWAS) to identify novel genic regions involved in the determination of the shade of bay. In total, 126 horses from five different breeds were r...
Fernández-Hernández P, Sánchez-Calabuig MJ, García-Marín LJ, Bragado MJ, Gutiérrez-Adán A, Millet Ó, Bruzzone C, González-Fernández L....Production of equine embryos in vitro is currently a commercial technique and a reliable way of obtaining offspring. In order to produce those embryos, immature oocytes are retrieved from postmortem ovaries or live mares by ovum pick-up (OPU), matured in vitro (IVM), fertilized by intracytoplasmic sperm injection (ICSI), and cultured until day 8-10 of development. However, at best, roughly 10% of the oocytes matured in vitro and followed by ICSI end up in successful pregnancy and foaling, and this could be due to suboptimal IVM conditions. Hence, in the present work, we aimed to elucidate the ...
Roy MM, Norton EM, Rendahl AK, Schultz NE, McFarlane D, Geor RJ, Mickelson JR, McCue ME.An 11G nucleotide repeat in the 3' UTR of FAM174A was recently postulated as a risk allele with a dominant mode of inheritance for equine metabolic syndrome (EMS) and laminitis status in Arabian horses. The objective of this project was to evaluate this hypothesis in a large and diverse across-breed population. A total of 301 ponies, 292 Morgans, 64 Arabians, 49 Tennessee Walking Horses and 59 Quarter Horses were genotyped for six observed G repeat alleles in the FAM174A 3' UTR. Phenotype data included laminitis status, baseline insulin, glucose, non-esterified fatty acids, triglycerides, adip...
Lancioni H, Cardinali I, Giontella A, Antognoni MT, Miglio A.In the last decades, Italy as well as other developed countries have registered a decrease in the population size of many local horse breeds. The continuous crossbreeding has determined the dilution of genetic heritage of several native breeds. The Italian Heavy Draught Horse (IHD) is the only autochthonous Italian coldblooded horse among these breeds; therefore, it represents a resource to be preserved. In 1927, the first generation of this breed was officially created by crossing different Heavy Draught horses with local mares and recorded in a Studbook. Methods: To provide the first compreh...
Salek Ardestani S, Aminafshar M, Zandi Baghche Maryam MB, Banabazi MH, Sargolzaei M, Miar Y.Natural selection and domestication have shaped modern horse populations, resulting in a vast range of phenotypically diverse breeds. Horse breeds are classified into three types (pony, light, and draft) generally based on their body type. Understanding the genetic basis of horse type variation and selective pressures related to the evolutionary trend can be particularly important for current selection strategies. Whole-genome sequences were generated for 14 pony and 32 light horses to investigate the genetic signatures of selection of the horse type in pony and light horses. In the overlappin...
Szóstek-Mioduchowska AZ, Baclawska A, Rebordão MR, Ferreira-Dias G, Skarzynski DJ.An increasing number of studies have shown that prostaglandins (PGs) exert multiple regulatory actions in the processes associated to tissue remodeling and fibrosis. Extracellular matrix (ECM) turnover is mediated by matrix metallopeptidases (MMPs). The knowledge about the regulation of their expression in mare endometrium is still limited. Thus, the aim of this study was to investigate whether: (i) profibrotic transforming growth factor (TGF)-β1 modulates PG production in equine endometrium; and (ii) PGE and PGF modulate MMPs, their tissue inhibitors (TIMPs), and collagen 1 (COL1) expression...
Novello G, Podico G, Segabinazzi LGTM, Lima FS, Canisso IF.The objective of this study was to compare semen parameters and embryo recovery rates of cooled stallion semen extended with INRA 96 or BotuSemen Gold. In experiment 1, 45 ejaculates from nine mature stallions were collected, assessed, and equally split between both extenders and then extended to 50 million sperm/mL. Then, the extended semen was stored in three passive cooling containers (Equitainer, Equine Express II, and BotuFlex) for 48 hours. In experiment 2, the same ejaculates extended in experiment 1 were cushion-centrifuged, the supernatant was discarded, and the pellets were resuspend...
Silveira BB, Souza EC, Dos Santos MDN, Porciuncula ML, Azevedo MDS, Duarte CA, de Carvalho AD, de Souza Junior P.Criollo horse breeding is an important economic activity in South America. Because of their athletic performance, these animals tend to show great incidence of musculoskeletal disorders, many of them diagnosed by means of perineural blocks. However, incorrect interpretation of these blocks may be due to anatomical differences in nerve distribution. The objective of this study was to describe the innervation of the digit region of thoracic limbs in Criollo horses, in order to improve the interpretation of tests for claudication diagnosis based on nerve block. Thirty thoracic limbs from Criollo ...
Tscharke M, Kind K, Kelly J, Kleemann D, Len J.Spontaneous nuclear maturation of mammalian oocytes can occur when physically removed from the ovarian follicle during in vitro oocyte maturation (IVM), largely because of a decrease in cyclic adenosine monophosphate (cAMP) concentration. Modulation of oocyte cAMP during IVM by using phosphodiesterase inhibitors has been shown to maintain elevated oocyte cAMP concentrations and control meiotic resumption of bovine and ovine oocytes. This study determined the effect of inclusion of isobutyl-1-methylxanthine (IBMX) during collection and the first 12 hours of incubation of equine oocytes on cAM...
Giontella A, Sarti FM, Biggio GP, Giovannini S, Cherchi R, Pieramati C, Silvestrelli M.The purpose of this study was to estimate the heritability and genetic correlations of four biometric measurements and an overall score (OS) in the Sardinian Anglo-Arab horse (SAA); moreover, the effect of inbreeding on these traits was investigated. A dataset with 43,624 horses (27,052 females and 16,572 males) was provided by the Agricultural Research Agency of Sardinia (AGRIS). Cannon bone circumference (BC), chest girth (CG), shoulder length (SL), and withers height (WH) were measured on 6033 SAA horses born in Sardinia between 1967 and 2005; beside the measurements, an overall score (OS) ...
Li B, He X, Zhao Y, Bai D, Du M, Song L, Liu Z, Yin Z, Manglai D.Horse testis development and spermatogenesis are complex physiological processes. To study these processes, three immature and three mature testes were collected from the Mongolian horse, and six libraries were established using high-throughput RNA sequencing technology (RNA-Seq) to screen for genes related to testis development and spermatogenesis. A total of 16,237 upregulated genes and 8,641 downregulated genes were detected in the testis of the Mongolian horse. These genes play important roles in different developmental stages of spermatogenesis and testicular development. Five genes with ...
Palmer E, Chavatte-Palmer P.Reproductive technologies aim at improving fertility with the ultimate result of improving genetic selection. In equidae, the respective contribution of different methods of horse management and breeding to genetic progress remain difficult to evaluate as breeding strategies affect the number of offspring per mare or stallion whereas different selection methods (based on pedigree, performance, genomics or progeny's performance) will be applicable at different ages, leading to different accuracy in the estimation of the breeding value. Here, a mathematical model was applied to evaluate theoreti...
Šandlová K, Komárková M, Ceacero F.Different forms of direct paternal investment have been described in mammals. One such species where paternal care was noticed, but remains poorly understood, is the horse (Equus caballus), where the male keeps a long-term relationship with several females and offspring. Therefore, the aim of this study was to analyse the interactions between the harem stallion and his foals. Two herds of Exmoor ponies living under semi-feral conditions in two separate reserves within Czech Republic were studied, each during one of the two consecutive breeding seasons (in 2016 and 2017). Both herds consisted o...
Nieth J, Krohn J.Aim of the study was to describe the echotexture and dimensions of the kidneys including the renal pelvis in neonatal foals using transabdominal sonography. Methods: In the course of a preliminary examination, sonographic examinations of the kidneys of 10 dead newborn foals were performed in order to determine their localization, measurement parameters, and echotexture. In subsequent necropsies, the kidneys were measured and the obtained values were compared with the sonographic measurements. A high level of agreement between the both measurement values could be demonstrated. In the main exami...
Blaue D, Schedlbauer C, Starzonek J, Gittel C, Brehm W, Blüher M, Pfeffer M, Vervuert I.Human obesity is linked with systemic inflammation. However, it is still controversial if equines produce more inflammatory cytokines with increasing body weight and if the production of those show breed type specific patterns. The main objective of this study was to determine if diet induced obesity is associated with increased inflammatory signatures in adipose tissue of equines and if a breed predisposition exists between ponies and horses. Additionally, we aimed to identify adipose tissue depot differences in inflammatory cytokine expression. Nineteen healthy, non-overweight and metabolica...
Wodas L, Mackowski M, Borowska A, Puppel K, Kuczynska B, Cieslak J.β-lactoglobulin is one of the most abundant milk whey proteins in many mammal species, including the domestic horse. The aim of this study was to screen for polymorphism in the equine LGB1 and LGB2 gene sequences (all exons, introns, and 5'-flanking region) and to assess potential relationship of particular genotypes with gene expression levels (measured in milk somatic cells) and milk composition traits (protein, fat, lactose, and total β-lactoglobulin content). Direct DNA sequencing analysis was performed for twelve horse breeds: Polish Primitive Horse (PPH), Polish Coldblood Horse (PCH), ...
Lazzari G, Colleoni S, Crotti G, Turini P, Fiorini G, Barandalla M, Landriscina L, Dolci G, Benedetti M, Duchi R, Galli C.Assisted reproduction technologies (ART) are well developed in humans and cattle and are gaining momentum also in the equine industry because of the fact that the mare does not respond to superovulation but can donate large numbers of oocytes through ovum pick up (OPU). After collection, the oocytes can be fertilized by intracytoplasmic sperm injection (ICSI) using a variety of stallion semen samples, even of poor quality, and the resulting embryos can establish high pregnancy rates after cryopreservation and transfer. The discoveries that equine oocytes can be held at room temperature without...
Miller SM.Endoscopy of thoroughbred (TB) yearlings at public auctions is common in South Africa. Laryngeal function (LF) is a common concern of buyers of young TBs. Cancellation of sale because of LF abnormalities is a concern for both the vendor and the buyer, with recurrent laryngeal neuropathy (RLN) being a common cause of sale cancellation. The aim of this descriptive study was to determine the prevalence of RLN at South African premier TB yearling sales. This study was designed as a retrospective descriptive analysis of upper respiratory tract (URT) endoscopic examinations to determine RLN grade, p...
Salek Ardestani S, Aminafshar M, Zandi Baghche Maryam MB, Banabazi MH, Sargolzaei M, Miar Y.Natural selection and domestication have shaped modern horse populations, resulting in a vast range of phenotypically diverse breeds. Horse breeds are classified into three types (pony, light, and draft) generally based on their body type. Understanding the genetic basis of horse type variation and selective pressures related to the evolutionary trend can be particularly important for current selection strategies. Whole-genome sequences were generated for 14 pony and 32 light horses to investigate the genetic signatures of selection of the horse type in pony and light horses. In the overlappin...
Rioja E, Cernicchiaro N, Costa MC, Valverde A.This study investigated associations between perioperative factors and probability of death and length of hospitalization of mares with dystocia that survived following general anesthesia. Demographics and perioperative characteristics from 65 mares were reviewed retrospectively and used in a risk factor analysis. Mortality rate was 21.5% during the first 24 h post-anesthesia. The mean ± standard deviation number of days of hospitalization of surviving mares was 6.3 ± 5.4 d. Several factors were found in the univariable analysis to be significantly associated (P < 0.1) with increased probabi...
Copy number variation (CNV) has been proved to be widespread in human, animal and plant genomes. Together with single nucleotide polymorphisms (SNPs), CVNs play a key role in genetic diversity. In this study, genome-wide detection of CNVs was performed based on SNP data from 24 Criollo Argentino horses genotyped with the GGP Equine70k array. Overall, 165 CNVs meeting stringent quality control criteria were identified and then aggregated into 87 CNV regions (CNVRs), representing a horse genome coverage of 13.69 Mb. Functional analysis of CNVRs allowed the identification of 337 genes implicate...
Hisey EA, Hermans H, Lounsberry ZT, Avila F, Grahn RA, Knickelbein KE, Duward-Akhurst SA, McCue ME, Kalbfleisch TS, Lassaline ME, Back W, Bellone RR.Distichiasis, an ocular disorder in which aberrant cilia (eyelashes) grow from the opening of the Meibomian glands of the eyelid, has been reported in Friesian horses. These misplaced cilia can cause discomfort, chronic keratitis, and corneal ulceration, potentially impacting vision due to corneal fibrosis, or, if secondary infection occurs, may lead to loss of the eye. Friesian horses represent the vast majority of reported cases of equine distichiasis, and as the breed is known to be affected with inherited monogenic disorders, this condition was hypothesized to be a simply inherited Mendeli...
Rockwell H, Mack M, Famula T, Sandmeyer L, Bauer B, Dwyer A, Lassaline M, Beeson S, Archer S, McCue M, Bellone RR.Equine recurrent uveitis (ERU) is characterized by intraocular inflammation that often leads to blindness in horses. Appaloosas are more likely than any other breed to develop insidious ERU, distinguished by low-grade chronic intraocular inflammation, suggesting a genetic predisposition. Appaloosas are known for their white coat spotting patterns caused by the leopard complex spotting allele (LP) and the modifier PATN1. A marker linked to LP on ECA1 and markers near MHC on ECA20 were previously associated with increased ERU risk. This study aims to further investigate these loci and identify a...
The Journal of heredityFebruary 21, 2008
Volume 99, Issue 2 130-136 doi: 10.1093/jhered/esm115
Rieder S, Hagger C, Obexer-Ruff G, Leeb T, Poncet PA.White markings and spotting patterns in animal species are thought to be a result of the domestication process. They often serve for the identification of individuals but sometimes are accompanied by complex pathological syndromes. In the Swiss Franches-Montagnes horse population, white markings increased vastly in size and occurrence during the past 30 years, although the breeding goal demands a horse with as little depigmented areas as possible. In order to improve selection and avoid more excessive depigmentation on the population level, we estimated population parameters and breeding value...
Cieslak J, Wodas L, Borowska A, Sadoch J, Pawlak P, Puppel K, Kuczynska B, Mackowski M.Equine milk is considered to be an interesting product for human nutrition, mainly owing to its low allergenicity and significant amounts of bioactive proteins, including lysozyme (LYZ) and lactoferrin (LTF). The present study assessed the effect of genetic factors on LYZ and LTF concentration variability in mare's milk. Results: Significant effects of horse breed and lactation stage on milk LYZ and LTF contents were observed. The highest level of LTF and the lowest concentration of LYZ were recorded for the Polish Warmblood Horse breed. The highest amounts of both proteins were found for the ...
Jackson BF, Dyson PK, Lonnell C, Verheyen KL, Pfeiffer DU, Price JS.The aim of this study was to determine whether bone biomarkers (osteocalcin, PICP, ICTP and CTX-I) could be used to identify 2- and 3-year-olds at increased risk of fracture in the subsequent flat racing season. It was concluded that these bone biomarkers cannot be used to identify 2- and 3-year-olds that sustain a fracture. Whether bone biomarkers have better predictive value in older horses or when measured serially in the same animal remains to be determined.
Harrison SP, Turrion-Gomez JL.The mitochondrial DNA (mtDNA) molecule, carrying genes encoding for respiratory chain enzymes, is a primary candidate for demonstrating associations between genotype and athletic performance in mammalian species. In humans, variation at seven protein encoding mitochondrial loci has been implicated in influencing fitness and performance characteristics. Although thoroughbred horses are selected for racing ability, there have not been any previous reported associations between genotypes and racecourse performance. The multi-factorial nature of the inheritance of racing ability is an obvious comp...
Nelson BB, Kawcak CE, Goodrich LR, Werpy NM, Valdés-Martínez A, McIlwraith CW.The femorotibial joints are a common source of lameness in Western performance horses. The objective of this prospective study was to compare the radiography, ultrasonography, computed tomographic arthrography (CTA), and arthroscopy findings in horses with lameness localized to the femorotibial joints. Twenty-five stifles in 24 horses were included and were evaluated with all four of these diagnostic methods. Defects detected in femorotibial joint structures were compared between diagnostic methods using a McNemar's test to evaluate for disagreement. Cranial medial meniscotibial desmopathy was...
Swierstra EE, Gebauer MR, Pickett BW.The cycle of the seminiferous epithelium of the stallion was
divided into eight stages, using as criteria the presence of meiotic divi-
sions, shape of the spermatid nuclei and location of spermatids with
elongated nuclei in the tubule. The mean frequencies ofstages 1 to 8 were
16\m=.\9, 14\m=.\9, 3\m=.\2, 15\m=.\8, 7\m=.\4, 13\m=.\5, 12\m=.\6 and 15\m=.\7%, respectively. The
duration of one cycle of the seminiferous epithelium was 12\m=.\2 days
(S.E.\m=+-\0\m=.\1) as determined by injecting a single dose of 700 \g=m\Ciof
[3H]thymidine into each spermatic artery of six stallions and rem...
The paper is a report from a workshop discussing equine endometritis, a condition affecting horse fertility. The event was held in honor of Professor John Hughes and his significant contributions […]
The Journal of heredityAugust 3, 2016
Volume 107, Issue 6 537-543 doi: 10.1093/jhered/esw042
Norton EM, Mickelson JR, Binns MM, Blott SC, Caputo P, Isgren CM, McCoy AM, Moore A, Piercy RJ, Swinburne JE, Vaudin M, McCue ME.Recurrent exertional rhabdomyolysis (RER) in Thoroughbred and Standardbred racehorses is characterized by episodes of muscle rigidity and cell damage that often recur upon strenuous exercise. The objective was to evaluate the importance of genetic factors in RER by obtaining an unbiased estimate of heritability in cohorts of unrelated Thoroughbred and Standardbred racehorses. Four hundred ninety-one Thoroughbred and 196 Standardbred racehorses were genotyped with the 54K or 74K SNP genotyping arrays. Heritability was calculated from genome-wide SNP data with a mixed linear and Bayesian model, ...
Balao da Silva CM, Ortega Ferrusola C, Morillo Rodriguez A, Gallardo Bolaños JM, Plaza Dávila M, Morrell JM, Rodriguez Martínez H, Tapia JA....At present, the only repeatable means of selecting the sex of offspring is the Beltsville semen sorting technology using flow cytometry (FC). This technology has reached commercial status in the bovine industry and substantial advances have occurred recently in swine and ovine species. In the equine species, however, the technology is not as well developed. To better understand the changes induced in stallion spermatozoa during the sorting procedure, pooled sperm samples were sorted: sperm motility and kinematics were assessed using computer assisted sperm analysis, sperm membrane integrity wa...
Sevinga M, Vrijenhoek T, Hesselinks JW, Barkema HW, Groen AF.This study was motivated by the hypothesis that the incidence of retained placenta (RP) in Friesian horses is associated with inbreeding. The objectives were to 1) calculate the inbreeding rate in the total registered Friesian horse population; 2) study the association of the inbreeding coefficient of the foal and the mare with the incidence of RP; and 3) study the heritability of RP in Friesian mares after normal foalings. Data from the total registered Friesian horse population from 1879 to 2000 (52,392 individuals) were collected from the registration files of the Friesian Horse Studbook. I...
Hall SE, Aitken RJ, Nixon B, Smith ND, Gibb Z.Oxidative stress is a major determinant of mammalian sperm function stimulating lipid peroxidation cascades that culminate in the generation of potentially cytotoxic aldehydes. The aim of this study was to assess the impact of such aldehydes on the functionality of stallion spermatozoa. The impact of exposure to exogenous acrolein (ACR) and 4-hydroxynonenal (4HNE) was manifested in a highly significant dose- and time-dependent increase in mitochondrial reactive oxygen species (ROS), total cellular ROS, a decrease in sperm motility, and a time-dependent increase in lipid peroxidation. Notably, ...
The Journal of hereditySeptember 13, 2011
Volume 102, Issue 6 753-758 doi: 10.1093/jhered/esr091
Guastella AM, Zuccaro A, Criscione A, Marletta D, Bordonaro S.Genetic diversity and relationship among 3 Sicilian horse breeds were investigated using 16 microsatellite markers and a 397-bp length mitochondrial D-loop sequence. The analysis of autosomal DNA was performed on 191 horses (80 Siciliano [SIC], 61 Sanfratellano [SAN], and 50 Sicilian Oriental Purebred [SOP]). SIC and SAN breeds were notably higher in genetic variability than the SOP. Genetic distances and cluster analysis showed a close relationship between SIC and SAN breeds, as expected according to the breeds' history. Sequencing of hypervariable mitochondrial DNA region was performed on a ...
Catalano DN, Coleman RJ, Hathaway MR, Neu AE, Wagner EL, Tyler PJ, McCue ME, Martinson KL.Adding breed type, height, and neck circumference to body length and girth circumference improves bodyweight (BW) estimation in different breeds of horses; however, equations have not been developed for all breed types. The objectives were to develop BW estimation equations for Miniature, saddle-type, and Thoroughbred horses using morphometric measurements. Measurements were collected on adult (≥3 years, nonpregnant) saddle-type (n = 209), adult (n = 249) and juvenile (<3 years, n = 61) Miniatures, and adult Thoroughbreds (n = 100). Personnel determined body condition score (BCS), m...
Minervini F, Lacalandra GM, Filannino A, Garbetta A, Nicassio M, Dell'aquila ME, Visconti A.Fumonisin B1 (FB1) is a mycotoxin produced by Fusarium species that exerts its toxic effect through interference with the sphingolipid pathway by inhibiting ceramide synthase. A FB1-dependent sperm toxicity was reported in boars. No information on FB1-related reproductive toxicity in stallions, the most sensitive animal species, has been reported. The aim of the present study was to assess the in vitro toxicity of FB1 on fresh and frozen-thawed equine spermatozoa by analyzing sperm viability, chromatin stability (SCSA) and reactive oxygen species (ROS) production by flow cytometry and sperm mo...
Sevinga M, Barkema HW, Stryhn H, Hesselink JW.During the foaling seasons of 1999 and 2000, the incidence of retained placenta in 495 normal parturitions of 436 Friesian brood mares was studied. Retained placenta was defined as a failure to expel all fetal membranes within 3 h of the delivery of the foal. Furthermore, the sex of the foal, month of breeding, sire and dam's sire, age of the mare, and time of day of foaling, were studied as factors that might be associated with retained placenta in Friesian mares after normal foalings, and with gestational length. The analysis was carried out using marginal logistic regression, and mixed line...
Klumplerova M, Vychodilova L, Bobrova O, Cvanova M, Futas J, Janova E, Vyskocil M, Vrtkova I, Putnova L, Dusek L, Marti E, Horin P.Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by bites of insects. IBH is a multifactorial disease with contribution of genetic and environmental factors. Candidate gene association analysis of IBH was performed in a group of 89 Icelandic horses all born in Iceland and imported to Europe. Horses were classified in IBH-affected and non-affected based on clinical signs and history of recurrent dermatitis, and on the results of an in vitro sulfidoleukotriene (sLT)-release assay with Culicoides nubeculosus and Simulium vittatum extract. Different genetic markers wer...
Guérin G, Bailey E, Bernoco D, Anderson I, Antczak DF, Bell K, Biros I, Bjørnstad G, Bowling AT, Brandon R, Caetano AR, Cholewinski G, Colling D....A low-density, male-based linkage map was constructed as one of the objectives of the International Equine Gene Mapping Workshop. Here we report the second generation map based on testing 503 half-sibling offspring from 13 sire families for 344 informative markers using the CRIMAP program. The multipoint linkage analysis localized 310 markers (90%) with 257 markers being linearly ordered. The map included 34 linkage groups representing all 31 autosomes and spanning 2262 cM with an average interval between loci of 10.1 cM. This map is a milestone in that it is the first map with linkage groups ...
Dell'Aquila ME, Albrizio M, Maritato F, Minoia P, Hinrichs K.Follicle atresia and granulosa cell apoptosis may be related to oocyte meiotic and developmental competence. We analyzed the relationships among granulosa cell apoptosis, initial cumulus morphology, oocyte nuclear maturation in vitro, and pronucleus formation after intracytoplasmic sperm injection (ICSI) in the horse. For each follicle, the size was measured and granulosa cells were used for DNA laddering analysis. Oocytes were evaluated for cumulus morphology, cultured for in vitro maturation, and submitted to ICSI. Apoptosis was categorized as absent, intermediate, or advanced according to t...
Jiang Q, Wei Y, Huang Y, Jiang H, Guo Y, Lan G, Liao J.The Debao pony (Equus caballus) is the most important local variety of domestic horses, and is strictly protected by the Chinese government. Their average adult withers height is 94.42±3.76 cm for males and 98.35±4.55 cm for females, respectively. In the present study, the complete sequence of the Debao pony mitochondrial genome was determined (GenBank Accession No. EU939445), and was found to be similar to other equine mitochondrial genomes. However, there were 85 nucleotide substitutions in the 13 protein-coding genes; the percentage of substitution was 0.8±0.1. Polymorphisms of mtDNA con...
Velie BD, Hamilton NA, Wade CM.Performance data for 164,046 Thoroughbreds entered in a race or official barrier trial in Australia were provided by Racing Information Services Australia. Analyses estimating the heritability for a range of racing performance traits using a single-trait animal model were performed using ASREML-R. Log of cumulative earnings (LCE; 0.19 ± 0.01), log of earnings per race start (0.23 ± 0.02) and best race distance (0.61 ± 0.03) were all significantly heritable. Fixed effects for sex were significant (P < 0.001) for all performance traits aside from LCE (P = 0.382). With the exception of annual ...
Wolfsberger WW, Ayala NM, Castro-Marquez SO, Irizarry-Negron VM, Potapchuk A, Shchubelka K, Potish L, Majeske AJ, Oliver LF, Lameiro AD....Since the first Spanish settlers brought horses to America centuries ago, several local varieties and breeds have been established in the New World. These were generally a consequence of the admixture of the different breeds arriving from Europe. In some instances, local horses have been selectively bred for specific traits, such as appearance, endurance, strength, and gait. We looked at the genetics of two breeds, the Puerto Rican Non-Purebred (PRNPB) (also known as the "Criollo") horses and the Puerto Rican Paso Fino (PRPF), from the Caribbean Island of Puerto Rico. While it is reasonable ...
Dini P, Troch L, Lemahieu I, Deblende P, Daels P.The objective of this study was to evaluate the accuracy of a novel, portable device (iSperm Equine for assessing concentration and motility of stallion semen). In the first experiment, semen concentration was determined by the iSperm Equine (Aidmics Biotechnology), Androvision (Minitube) and NucleoCounter SP-100™ (ChemoMetec). The total motility and progressive motility were determined by the iSperm Equine and the Androvision using the manufacturer's guidelines. Frozen/thawed semen samples (n = 33) at various dilutions were analysed for concentration and motility with the above-mentioned ...
Grilz-Seger G, Reiter S, Neuditschko M, Wallner B, Rieder S, Leeb T, Jagannathan V, Mesarič M, Cotman M, Pausch H, Lindgren G, Velie B, Horna M....The roan coat color in horses is characterized by dispersed white hair and dark points. This phenotype segregates in a broad range of horse breeds, while the underlying genetic background is still unknown. Previous studies mapped the roan locus to the KIT gene on equine chromosome 3 (ECA3). However, this association could not be validated across different horse breeds. Performing a genome-wide association analysis (GWAS) in Noriker horses, we identified a single nucleotide polymorphism (SNP) (ECA3:g.79,543.439 A > G) in the intron 17 of the KIT gene. The G -allele of the top associated SNP...
Sadek MH, Al-Aboud AZ, Ashmawy AA.Data of 13 body measurements have been analysed from 166 Arabian horses, 123 mares and 43 stallions, ranging from 49 to 298 months of age, belonging to Alzahraa stud, Cairo, Egypt. General linear model was used to study age and gender effects on these measures. Gender was a significant source of variation for most studied traits, but not for neck girth, cannon bone circumference of fore and hind legs, and pastern girth of fore and hind legs. Age significantly affected pastern girths of fore and hind legs and cannon bone circumference of fore legs, while there was no significant effect on the o...
