Analyze Diet

Topic:Population Dynamics

The population dynamics of horses refers to the study of changes in horse populations over time, influenced by factors such as birth rates, death rates, immigration, and emigration. These dynamics are shaped by environmental conditions, resource availability, predation, and human intervention. Understanding population dynamics is essential for managing wild horse populations and ensuring sustainable practices in breeding and conservation efforts. This page compiles peer-reviewed research studies and scholarly articles that explore the factors affecting horse population dynamics, including genetic diversity, habitat utilization, and the impact of management strategies on population stability and growth.
Phenotypic characterization through identification of gait and coat color phenotype of the Mountain Pleasure Horse.
Journal of equine veterinary science    June 17, 2026   106066 doi: 10.1016/j.jevs.2026.106066
Irons A, Culwell J, Nicodemus MC, Vandiver M, North E, Cavinder C, Rios de Alvarez L, Williams T.Phenotypic characterization of traits like gait and coat color is useful for minor breed identification and conservation. The Mountain Pleasure Horse (MPH) is a minor American breed as it is listed as threatened by the Livestock Conservancy. Objective: The study objective was to utilize phenotypic characterization for identifying gait and coat color phenotype of the MPH. Methods: Gait was characterized utilizing frame-by-frame analysis to identify spatiotemporal variables of purebred horses (n = 6) performing the flat walk and saddle rack. Coat color was characterized using coat color assi...
Integrative Advances in Equine Genomics From Reference Assemblies to Evolutionary History and Key Traits.
Evolutionary applications    June 17, 2026   Volume 19, Issue 6 e70283 doi: 10.1111/eva.70283
Lu Y, Ma R, Wang B, Wu J, Chong Y, Gao Z, Deng W.Horses are major domestic animals and cultural symbols that have accompanied humans for millennia. They underpin transport, agriculture, warfare and sport, and also provide a model for studying domestication, complex traits and adaptive evolution. Recent work in equine genomics has now generated a much richer picture of how these roles are grounded in the genome. This review brings together advances in several connected areas: the construction and refinement of reference assemblies; genomic reconstructions of origin, domestication and dispersal; global and regional patterns of genetic diversit...
A Breed-Specific SNP Panel With Higher Theoretical Exclusion Power and Practical Equivalence to International Standards for Parentage Testing in Pura Raza Española Horses.
Animal genetics    June 12, 2026   Volume 57, Issue 3 e70147 doi: 10.1002/age.70147
Laseca N, Molina A, Marshall T, González I, Poyato-Bonilla J, Valera M.Accurate parentage assignment is essential for managing livestock breeding and genetic improvement. This study evaluated a breed-specific SNP panel (375 SNPs) for the Pura Raza Española (PRE) horse, comparing its performance against the traditional STR reference panel (18 microsatellite) and the international ISAG SNP core panel (378 SNPs) across population scenarios differing in levels of inbreeding and kinship. The PRE-specific SNPs were selected from the Axiom EQUIGENE array based on high genotyping reliability (call-rate > 99%), Mendelian error minimization, Hardy-Weinberg equilibr...
The “gait keeper” mutation does not influence gait scores in Pêga donkeys: a preliminary result.
Journal of equine veterinary science    June 11, 2026   Volume 165 106056 doi: 10.1016/j.jevs.2026.106056
Santana CJS, Rocha VCP, de Moraes JVS, Senes BB, Maciel SVSA, Oliveira IPP, Costa RB, Alves JS, de Camargo GMF.The DMRT3 "gait keeper" mutation is a major determinant of locomotor patterns in horses, but its role in donkeys remains unclear. This study evaluated the association between this polymorphism and gait performance in Pêga donkeys, a breed selected for gaited locomotion. A total of 260 animals were phenotyped for gait scores and genotyped by PCR-sequencing targeting exon 2 of DMRT3. All individuals were homozygous for the wild-type allele (CC), and the mutant A allele was not detected. The monomorphism precludes any association with gait scores, possibly indicating that this DMRT3 mutation has...
Successful restoration of heathlands and grasslands associated with long-term habitat preferences of cattle and horses: Insights from GPS tracking.
Journal of environmental management    June 9, 2026   Volume 411 130113 doi: 10.1016/j.jenvman.2026.130113
Hendler R, Tischew S, Hensen H, Metze K, Schütz L, Bade K, Fischer C.Long-term, year-round grazing by large herbivores is increasingly used to restore degraded temperate heathlands and grasslands, yet the behavioral mechanisms of grazers underlying restoration remain insufficiently understood. We combined over 13 years of high-resolution GPS-tracking data of free-ranging Heck cattle and Konik horses with repeated vegetation surveys across various habitat types (encroachment-derived Calamagrostis epigejos stands, dry sandy grasslands, dry heaths, and pioneer forests) in Central Germany. We quantified how habitat preference and vegetation structure co-develop und...
Genetic diversity of horses of the Sargarinsko-Alexeevskaya and Irmen cultures of the Ob-Irtysh region of Western Siberia and their genetic proximity to modern horses of indigenous breeds.
Vavilovskii zhurnal genetiki i selektsii    June 5, 2026   Volume 30, Issue 3 451-460 doi: 10.18699/vjgb-26-49
Genetic diversity of horses of the Sargarinsko-Alexeevskaya and Irmen cultures of the Ob-Irtysh region of Western Siberia and their genetic proximity to modern horses of indigenous breeds. Генетическое разнообразие лошадей саргаринско-алексеевской и ирменской культур Западной Сибири и их генетическое родство с современными лошадьми аборигенных пород.
Comparative metagenomic analysis of gut microbiomes in Yunnan ponies and Dutch warmblood horses.
Frontiers in microbiology    June 5, 2026   Volume 17 1807081 doi: 10.3389/fmicb.2026.1807081
Cha J, Yang J, Zhang Z, Qian L, Yang F, Li S, Li J, Jian Z, Cheng W.The Yunnan pony is an officially protected pony breed in China. However, its gut microbiome characteristics remain largely unexplored. This study aimed to compare the gut microbiome and antibiotic resistance genes (ARGs) profiles between Yunnan ponies and Dutch warmblood horses. Unassigned: A total of 14 fresh fecal samples were collected from Yunnan ponies and Dutch warmblood horses. Metagenomic sequencing was employed to comprehensively analyze and compare the gut microbial composition, function, and ARGs profiles between the two breeds. Unassigned: The results showed no significant differen...
Genomic diversity of multidrug-resistant Rhodococcus equi: novel sequence types, pangenome architecture, and phylogenomic evolution.
Applied and environmental microbiology    June 4, 2026   e0248625 doi: 10.1128/aem.02486-25
Lamichhane B, Kabir A, Adams AA, Burns L, Johnson B, Sponseller B, Helmy YA.Rhodococcus equi is a major cause of life-threatening pneumonia in foals under 6 months of age and an opportunistic pathogen in immunocompromised humans. Although common in soil and equine farm environments, its evolutionary dynamics, virulence architecture, and pathways of antimicrobial resistance (AMR) emergence remain poorly understood. This study integrated phenotypic characterization and whole-genome sequencing of 46 R. equi isolates from horses submitted for necropsy (n = 45) and equine fecal samples (n = 1) in Kentucky between January 2022 and December 2023 to define their resistance la...
Genetic variability and associations of Trakehner and other horse populations in Lithuania.
Archives animal breeding    June 2, 2026   Volume 69, Issue 2 323-336 doi: 10.5194/aab-69-323-2026
Račkauskaitė A, Šveistienė R, Razmaitė V, Jatkauskienė V, Marašinskienė Š.To obtain genetic parameters relevant for the management of animal genetic resources, this study provides a comparative characterization of the Trakehner (TRAK) horse population in relation to four other horse populations maintained in Lithuania - Arabian (ARAB), Baltic Warmblood (BW), Lithuanian Warmblood (LW), and Zemaitukai (ZEM). These populations represent diverse histories, selection goals, and breeding practices. Pedigree data ( 22 666) and parentage verification genetic data based on blood group markers ( 1293) were used to evaluate genetic diversity, population structure, and inter-...
Research Trends and Emerging Frontiers in Racehorse Genetics: A Bibliometric Analysis.
Animals : an open access journal from MDPI    June 2, 2026   Volume 16, Issue 11 1705 doi: 10.3390/ani16111705
Huang Q, Yao X, Yang X, Wang T, Li X, Shan D, Su Y, Wang J.The global horse racing industry relies heavily on elite breeding. Therefore, a molecular understanding of athletic traits is crucial for the industry's advancement. This study utilized Bibliometrix, VOSviewer, and CiteSpace to conduct a comprehensive bibliometric analysis of 869 publications in the Web of Science Core Collection (2011-2025), decoding the academic landscape and evolutionary trajectory of equine genetics. The results indicate a significant upward trend in academic output since 2019, with the United States, South Korea, and the United Kingdom emerging as the primary contributors...
Estimating the economic value of working donkeys in Ethiopia.
Preventive veterinary medicine    May 30, 2026   Volume 254 106926 doi: 10.1016/j.prevetmed.2026.106926
Asteraye GB, Jobling R, Jemberu WT, Pinchbeck G, Knight-Jones TJD, Chaters GL, Rushton J.There is limited empirical evidence on the quantitative economic contribution of donkeys to livelihoods, leading to their undervaluation and exclusion from policy. Here an enterprise budget analysis is embedded within a stochastic dynamic population model for three production systems in Ethiopia to evaluate system inputs, outputs and the economic contribution of donkeys. The model was parameterised using data from household surveys, focus group discussions and key informant interviews, supplemented by literature. The economic value of donkeys' (unpaid) homestead and agricultural services was e...
Whole Genome Data Uncover the Complex Origins of Polish Konik Horses.
Animals : an open access journal from MDPI    May 29, 2026   Volume 16, Issue 11 1669 doi: 10.3390/ani16111669
Musiał AD, Ropka-Molik K, Szmatoła T, Podstawski P, Finno CJ, Bieniek A, Wilczyński J, Stefaniuk-Szmukier M.Polish Konik is a native horse breed from Poland often regarded as living descendants of the extinct Tarpan, which has been crucial to the breed's conservation status and cultural importance. To evaluate Polish Konik origins, we sequenced 12 whole genomes and compared them with 148 horse genomes, including those of modern breeds, ancient Polish horses, Przewalski horses, and the Tarpan. The ADMIXTURE results showed that Polish Konik is dominated by a single ancestral component, which is also common among ancient Polish samples and several primitive breeds. The PCA places Polish Konik in a comp...
Extinct Dalian horse as a genetic bridge between Late Pleistocene North American and Eurasian equids.
Proceedings. Biological sciences    May 27, 2026   Volume 293, Issue 2071 20260314 doi: 10.1098/rspb.2026.0314
Song S, Xiao B, Xing F, Qi L, Bao L, Hou Y, Zhang Y, Zheng M, Hu J, Zheng L, Yu D, Deng T, Hofreiter M, Lai X, Yuan J, Sheng G.Pleistocene caballine horses exhibited considerable genetic diversity and maintained broad population connectivity across their range. The extinct Dalian horse (Equus dalianensis) from northeastern China likely contributed to this network. Here, we sequenced 20 complete mitochondrial and two nuclear genomes, establishing the Dalian horse as a distinct genetic clade within Northeast Eurasian caballines and extending its known geographic distribution. Ancestry component analyses revealed a distinctive component of Eastern Beringian (E-EBer), i.e. American ancestry in Dalian horses, absent from o...
Genome-Wide Association Study Reveals Genetic Loci Associated with Body Measurement Traits in Yanqi Horses.
Animals : an open access journal from MDPI    May 24, 2026   Volume 16, Issue 11 1597 doi: 10.3390/ani16111597
Sun W, Shen Z, Cairen D, Luo P, Yao X, Meng J, Zeng Y.Body measurement traits are a direct production indicator reflecting growth status and guiding genetic selection. Identifying molecular markers associated with body measurement traits could accelerate animal breeding programs. The Yanqi horse, an important indigenous breed in Xinjiang, is primarily distributed in the Bayingolin Mongol Autonomous Prefecture. However, molecular markers linked to body measurement traits in Yanqi horses remain uncharacterized. In the present study, whole-genome resequencing was performed on 183 Yanqi horses, yielding 13,366,672 single-nucleotide polymorphisms (SNP...
Open habitats and species differences shape space use in semi-feral cattle and horses across Danish rewilding sites.
Environmental monitoring and assessment    May 23, 2026   Volume 198, Issue 6 639 doi: 10.1007/s10661-026-15487-8
Bergin MD, Börger L, da Rocha ÉG, Havmøller RW, Jensen M, Svenning JC.Large herbivores can strongly influence ecosystem structure and biodiversity, making knowledge of their space use important for trophic rewilding. We used GPS-tracking data collected over two years from 10 semi-feral cattle and 17 horses across ten Danish rewilding sites to analyse habitat use in a use-availability framework using resource selection functions (RSFs), complemented by direct behavioural observations. Both species showed large individual variability but overall used habitats disproportionately to availability, with higher relative use of open habitats; including dry grassland and...
Establishment and evaluation of hematological and serum biochemical reference intervals in Chinese local donkey populations.
BMC veterinary research    May 18, 2026   doi: 10.1186/s12917-026-05556-y
Zhu Q, Khan MZ, Jing Y, Liu X, Chen W, Geng M, Liu B, Zhang Y, Xing S, Peng Y, Wang C.Background: Reliable interpretation of hematological and serum biochemical test results in donkeys benefits from the use of population- and management-system-adapted reference intervals (RIs). However, standardized and CLSI-compliant RIs for Chinese local donkeys are still unavailable, limiting their clinical and epidemiological application. This study aimed to establish hematological and serum biochemical RIs for Chinese local donkeys using a large, multi-farm dataset, and to evaluate the effects of farm origin, age, and sex on these parameters. Blood samples were collected from healthy donke...
Genetic diversity of Dermacentor nitens (Acari: Ixodidae) collected on horses from western Cuba.
Journal of medical entomology    May 17, 2026   Volume 63, Issue 3 tjag059 doi: 10.1093/jme/tjag059
Roblejo-Arias L, Diaz-Sánchez AA, Marrero-Perera R, Lobo-Rivero E, Corona-González B, Chilton NB.The tropical horse tick, Dermacentor nitens Neumann, 1897, has a wide distribution throughout the Neotropics, and is a vector of protozoan haemoparasites that cause equine piroplasmosis. Despite this, little is known about the genetic diversity of this tick species, particularly in Cuba, where horses are important domestic animals used in agriculture and for transportation. The objective of this study was to assess the magnitude of genetic variation in 115 D. nitens adults (57 females and 58 males) collected from horses in the Cuban province of Mayabeque using sequence data of two mitochondria...
Genetic Diversity and Population Structure in Seven Lipizzan Populations Based on Microsatellite Genotyping.
Animals : an open access journal from MDPI    May 15, 2026   Volume 16, Issue 10 1516 doi: 10.3390/ani16101516
Rogić B, Moravčíková N, Margeta P, Štrbac L, Zorc M, Kovács M, Vostry L, Kasarda R, Posta J.Lipizzan horses, bred for over four centuries, represent a unique genetic, cultural and historic resource. This study assessed genetic diversity and population structure across seven European Lipizzan populations, with emphasis on the Bosnia and Herzegovina population. A total of 547 Lipizzan horses were genotyped using 12 microsatellite markers. The parameters of genetic variability, admixture level and migration rate were calculated. The mean number of alleles, effective number of alleles and Shannon's information index were 5.78, 3.24 and 1.31, respectively. The average fixation indices wer...
Unraveling the genomic architecture of hock conformation defects in Pura Raza Española horses.
Journal of animal science    May 13, 2026   skag116 doi: 10.1093/jas/skag116
Laseca N, Molina A, Ziadi C, Perdomo-Gonzalez DI, Valera M.Conformational traits define a horse's shape and morphology, heavily influencing its functionality, sport performance, health, and appearance, making conformation a critical selection criterion in horse breeding. However, the genomic basis of conformational defects, specifically those affecting the hock, remains largely unexplored. This research aimed to identify the genomic regions associated with hock defects using a large cohort of Pura Raza Española (PRE) horses. A total of 58,930 horses were evaluated for hock angle, with 4,122 genotyped on high or medium density arrays. For this purpose...
The prevalence of Streptococcus equi subsp. equi carriers in the Netherlands.
Equine veterinary journal    April 26, 2026   doi: 10.1002/evj.70177
Houben RMAC, Broens EM, Broekhuizen-Stins MJ, Sloet van Oldruitenborgh-Oosterbaan MM, van Maanen C, Heesterbeek JAP.Streptococcus equi subspecies equi (S. equi) carriers are thought to be important drivers for strangles outbreaks. Limited data are available on the prevalence of carriers in European horse husbandry settings. Objective: To estimate the prevalence of S. equi carriers among apparently healthy adult horses and ponies in the Netherlands. Methods: Cross-sectional survey. Methods: The carrier prevalence in the Netherlands was estimated, detecting carriers by PCR analysis of three repeated nasopharyngeal lavages at weekly intervals. Bayesian methods were used for a true prevalence estimation. Result...
Genomic diversity and structure in arabian horses revealed by whole-genome sequencing: establishment of an allele frequency database of common genetic variation.
BMC genomics    April 20, 2026   doi: 10.1186/s12864-026-12862-0
Szmatoła T, Finno C, Gurgul A, Heath H, Stefaniuk-Szmukier M, Almarzook S, Norton E, Ropka-Molik K.BACKGROUND: The Arabian horse is a culturally and historically influential breed that has contributed to the development of many modern horse populations. However, genomic resources for this breed remain limited, particularly population-level allele frequency datasets that support studies of genetic diversity, selection, and disease. The aim of this study was to generate a comprehensive allele frequency database for Arabian horses using representative sampling and high-coverage whole-genome sequencing. RESULTS: We generated the first publicly available allele frequency database for the Arabian...
Morphometric Characterization and Preliminary Heritability Estimates of Body Measurements in the Polish Konik Populations.
Animals : an open access journal from MDPI    April 14, 2026   Volume 16, Issue 8 1190 doi: 10.3390/ani16081190
Pasicka E, Sobek Z, Wierzbicki H, Różańska-Zawieja J, Nienartowicz-Zdrojewska A.The objective of this paper is to demonstrate the morphometric diversity of 172 Polish Koniks from the largest Polish breeding centers and to assess their genetic diversity by estimating the effective population size () and heritabilities () of the studied traits. The animals were bred under a stable housing system. Horses of both sexes aged 3 to 24 years were analyzed. Each horse was characterized with 40 metric traits. Multifactorial analyses (PCA, DA) and the REML method were applied to reveal the exterior differentiation and the development of distinct morphometric types. The findings esta...
Genetic diversity in the Criollo Argentino horse from SNP array data.
Genetica    April 11, 2026   Volume 154, Issue 1 16 doi: 10.1007/s10709-026-00266-7
The Criollo Argentino horse is a national symbol and a heritage breed that represents both cultural identity and a key component of traditional production systems in Argentina. This study aimed to assess the genetic differentiation of the Criollo Argentino relative to other horse breeds and to infer potential factors shaping its diversity through the genomic analysis of 24 representative animals. Samples were genotyped using a medium-density SNP array containing 65,157 markers, and genetic diversity analyses were conducted across autosomal SNP sets filtered under different criteria. Contempora...
Comprehensive molecular characterization of Theileria equi: Detection, genetic diversity, and risk factors assessment.
Experimental parasitology    April 11, 2026   109135 doi: 10.1016/j.exppara.2026.109135
Maharana BR, Ganguly A, Malik R, Kumar A, Khanna S, Kumar B, Potliya S, Singh H, Dash A, Sahu S.Equine piroplasmosis, caused by Theileria equi, has been widely studied globally, but genetic diversity research in India remains limited. Analysis of 306 horse blood samples revealed T. equi infection in 10.78% by microscopy and 21.24% by PCR. Universal primers targeting 18S rRNA of T. equi and Babesia caballi were used, followed by species-specific primers generating 435 bp amplicons. Sequenced PCR-positive samples revealed high homology (99.52-100% in India, 95.89-100% globally), with all Indian isolates classified as genotype A. The EMA-1 gene phylogenetic analysis confirmed the insights f...
Pedigree Investigation of Polish Sport Horses in Show Jumping: Insights for Global Breeding.
Animals : an open access journal from MDPI    April 10, 2026   Volume 16, Issue 8 1152 doi: 10.3390/ani16081152
Próchniak T.The aim of this study was to characterise the pedigree and genetic structure of Polish Sport Horses competing in Grand Prix show jumping events and to assess the implications for international sport horse breeding. Pedigrees of 513 horses were analysed, encompassing a total of 18,836 individuals over a maximum of 16 generations. The completeness and depth of the pedigrees allowed for a reliable estimation of inbreeding coefficients and genetic diversity. The mean inbreeding coefficient was low (0.645%), yet 82% of the horses exhibited some degree of inbreeding. The greatest loss of genetic var...
DMRT3 Gene Variations in Horse Breeds Selected for Gaited Movement – Established Research and Novel Findings.
Journal of equine veterinary science    April 3, 2026   105877 doi: 10.1016/j.jevs.2026.105877
Ropka-Molik K, Musiał AD, Majtyka A, Bieniek A, Ayad A, Muszyński S, Stefaniuk-Szmukier M.The DMRT3 gene, often referred to as the "gait keeper," plays a key role in controlling alternative gaits in horses, such as tölt and pace. This study aimed to determine the frequency of known and to screen for potential novel polymorphisms within the second exon of the DMRT3 gene. Methods: A total of 244 blood or hair samples were collected from representative individuals of the six horse breeds: gaited (Icelandic Horse, French Trotter), non-gaited (Arabian Horse, Malopolski Horse), and pony breeds (Welsh Pony, Shetland Pony). Methods: The second exon of the DMRT3 gene analyzed using Sanger ...
Unveiling genetic diversity in Egyptian Arabian horses (Equus caballus) through cytogenetic and ISSR marker analysis.
Research in veterinary science    April 1, 2026   Volume 206 106156 doi: 10.1016/j.rvsc.2026.106156
Ibrahim MA, Noshy MM, Mohamed HRH, Abd El-Gawad MEH.This study combined classical cytogenetics and ISSR molecular markers to characterize genetic diversity in 24 Egyptian Arabian horses. Karyotyping revealed the standard equine chromosome number (2n = 64) with no numerical or structural abnormalities. Chromosome measurements were consistent with ISCN Equine standards: autosomal relative lengths (RL%) followed the expected size hierarchy, biarmed chromosomes displayed metacentric to submetacentric morphology (CI = 37-50%), and recalculated centromeric indices confirmed the presence of measurable p-arms on all acrocentric chromosomes. ISSR an...
An increased number of heterozygous calls in the AxiomTM Equine Genotyping Array.
G3 (Bethesda, Md.)    March 31, 2026   jkag085 doi: 10.1093/g3journal/jkag085
Gmel AI, Pirani A, McInnis L, Neuditschko M.Single nucleotide polymorphism (SNP) arrays are commonly used in livestock genetics to investigate complex traits including genome-wide associations and fine mapping, genomic prediction and genetic diversity analyses. In a European equine diversity study, we analysed the AxiomTM Equine 670K SNP genotype data from 2,768 equids representing 20 horse breeds and one donkey breed. Using a strict detection setting to identify genome-wide runs of homozygosity (ROH), 169 purebred horses displayed fewer ROH segments than F1 crosses. Under medium and relaxed settings, ROH counts increased, while some ho...
Population Structure and Genetic Diversity Among Lipizzan Mare Families in Hungary Based on Microsatellite Genotyping.
Animals : an open access journal from MDPI    March 31, 2026   Volume 16, Issue 7 1062 doi: 10.3390/ani16071062
Kovács M, Hegedűs B, Mihók S, Knop R, Szabó C, Posta J.The conservation of genetic diversity in historically structured horse breeds requires fi-ne-scale population genetic evaluation beyond conventional pedigree-based approaches. The present study assessed genetic diversity, population structure, and mare family differentiation in a Lipizzan horse population using 16 ISAG/FAO-recommended microsatellite markers. A total of 172 mares representing 29 mare families were genotyped. All loci were polymorphic, with a mean number of alleles per locus of 6.69 and a mean effective number of alleles of 3.56. The average polymorphism information content (PIC...
Pedigree-Based Assessment of Genetic Structure and Disease-Associated Variants in Friesian Horses in Brazil.
Journal of equine veterinary science    March 20, 2026   105860 doi: 10.1016/j.jevs.2026.105860
Rocha IAB, Araujo F, Rosa LP.Background: Friesian horses are recognized for severe genetic restriction due to intensive selection. Still, the genetic diversity, founder representation, and prevalence of inherited disorders in the Brazilian Friesian population, which is comprised of fewer than 500 individuals, have not been previously investigated AIMS/OBJECTIVES: characterize the genetic diversity, inbreeding, founder representation using pedigree-based tools, and frequency of known pathogenic, behavioral, and white spotting alleles in Friesian horses registered in Brazil METHODS: Pedigree data from 411 Friesian horses (2...