Mitochondrial DNA and Y chromosome reveal the genetic structure of the native Polish Konik horse population.

Polish Konik remains one of the most important horse breeds in Poland. The primitive, native horses with a stocky body and mouse-like coat color are protected by a conservation program, while their Polish population consists of about 3,480 individuals, representing 16 dam and six sire lines. To define the population's genetic structure, mitochondrial DNA and Y chromosome sequence variables were identified. The mtDNA whole hypervariable region analysis was carried out using the Sanger sequencing method on 233 Polish Koniks belonging to all dam lines, while the Y chromosome analysis was performed with the competitive allele-specific PCR genotyping method on 36 horses belonging to all sire lines. The analysis of the mtDNA hypervariable region detected 47 SNPs, which assigned all tested horses to 43 haplotypes. Most dam lines presented more than one haplotype; however, five dam lines were represented by only one haplotype. The haplotypes were classified into six (A, B, E, J, G, R) recognized mtDNA haplogroups, with most horses belonging to haplogroup A, common among Asian horse populations. Y chromosome analysis allocated Polish Koniks in the Crown group, condensing all modern horse breeds, and divided them into three haplotypes clustering with coldblood breeds (28 horses), warmblood breeds (two horses), and Duelmener Pony (six horses). The clustering of all Wicek sire line stallions with Duelmener horses may suggest a historical relationship between the breeds. Additionally, both mtDNA and Y chromosome sequence variability results indicate crossbreeding before the studbooks closure or irregularities in the pedigrees occurred before the DNA testing introduction.

Historical dataset of osteological and archaeological records for equines on Crete.

We gathered evidence on the occurrence of equines in the island of Crete from the Neolithic until 1895. We relied on published archaeological and osteological records plus on historical written documents. Our dataset includes a description of the type of evidence, where this was located, and the associated absolute and relative chronologies. The collected data can be used to investigate the past spread of equids in Crete (Equus asinus and Equus caballus), their socioeconomic status, and the development of the local Cretan breed. The dataset is made available via the Abraxas data community within the Pandora data platform. This community is devoted to the historical study of horses. The dataset presented here is a component of a project tracing the history of the Cretan horse until present day.

Antimicrobial Resistance in Vaginal Bacteria in Inseminated Mares.

Antimicrobials are added to semen extenders to inhibit the growth of bacteria that are transferred to the semen during collection. However, this non-therapeutic use of antimicrobials could contribute to the development of antimicrobial resistance. The objective of this study was to determine changes in the antibiotic susceptibility of vaginal microbiota after artificial insemination. Swabs were taken from the vagina of 26 mares immediately before artificial insemination and again 3 days later. Bacteria isolated from the vagina at both time points were subjected to antibiotic susceptibility testing and whole-genome sequencing. In total, 32 bacterial species were identified. There were increases in the resistance of Escherichia coli to trimethoprim (p = 0.0006), chloramphenicol and (p = 0.012) tetracycline (p = 0.03) between day 0 and day 3. However, there was no significant effect of exposure to antibiotics in semen extenders with respect to the resistance of Staphylococcus simulans and Streptococcus equisimilis (p > 0.05). Whole-genome sequencing indicated that most phenotypic resistance was associated with genes for resistance. These results indicate that the resistance patterns of vaginal bacteria may be affected by exposure to antibiotics; therefore, it would be prudent to minimize, or preferably, avoid using antibiotics in semen extenders.

Replacement of microsatellite markers by imputed medium-density SNP arrays for parentage control in German warmblood horses.

In horses, parentage control is currently performed based on an internationally standardized panel of 17 microsatellite (MS) markers comprising 12 mandatory and five optional markers. Unlike MS, single nucleotide polymorphism (SNP) profiles support a wider portfolio of genomic applications, including parentage control. A transition to SNP-based parentage control is favorable, but requires additional efforts for ensuring generation-overlapping availability of marker genotypes of the same type. To avoid double genotyping of either parents or offspring for changing to SNP technology and enable efficient transition, we tested whether MS genotypes used for parentage control could be reliably imputed from a medium-density SNP panel in German warmblood horses. Imputation accuracy was tested in a tenfold cross-validation with two approaches: within breed (option A) and across breeds (option B). Average imputation accuracies of 97.98% (A) and 96.17% (B) were achieved, respectively. Due to interbreed differences in genotyping rates, five MS markers of low genotyping rate (GTR; < 90%) could be imputed with higher accuracy within breed (98.18%) than across breeds (90.73%). MS markers with high GTR performed homogeneously well in option B (98.44%) and showed slightly lower accuracy in option A (97.90%). Among these markers, AHT5 proved to be problematic for imputation regardless of the approach, revealing accuracies of 86.40% (A) and 88.70% (B). Better results for MS markers with high GTR and savings in computational processing justified the choice of option B for routine implementation. To date, more than 9500 horses have undergone the new parentage control based on imputed MS genotypes.

Y-Chromosomal Insights into Breeding History and Sire Line Genealogies of Arabian Horses.

The Y chromosome is a valuable genetic marker for studying the origin and influence of paternal lineages in populations. In this study, we conducted Y-chromosomal lineage-tracing in Arabian horses. First, we resolved a Y haplotype phylogeny based on the next generation sequencing data of 157 males from several breeds. Y-chromosomal haplotypes specific for Arabian horses were inferred by genotyping a collection of 145 males representing most Arabian sire lines that are active around the globe. These lines formed three discrete haplogroups, and the same haplogroups were detected in Arabian populations native to the Middle East. The Arabian haplotypes were clearly distinct from the ones detected in Akhal Tekes, Turkoman horses, and the progeny of two Thoroughbred foundation sires. However, a haplotype introduced into the English Thoroughbred by the stallion Byerley Turk (1680), was shared among Arabians, Turkomans, and Akhal Tekes, which opens a discussion about the historic connections between Oriental horse types. Furthermore, we genetically traced Arabian sire line breeding in the Western World over the past 200 years. This confirmed a strong selection for relatively few male lineages and uncovered incongruences to written pedigree records. Overall, we demonstrate how fine-scaled Y-analysis contributes to a better understanding of the historical development of horse breeds.

Genetic and genomic characterization followed by single-step genomic evaluation of withers height in German Warmblood horses.

Reliability of genomic predictions is influenced by the size and genetic composition of the reference population. For German Warmblood horses, compilation of a reference population has been enabled through the cooperation of five German breeding associations. In this study, preliminary data from this joint reference population were used to genetically and genomically characterize withers height and to apply single-step methodology for estimating genomic breeding values for withers height. Using data on 2113 mares and their genomic information considering about 62,000 single nucleotide polymorphisms (SNPs), analysis of the genomic relationship revealed substructures reflecting breed origin and different breeding goals of the contributing breeding associations. A genome-wide association study confirmed a known quantitative trait locus (QTL) for withers height on equine chromosome (ECA) 3 close to LCORL and identified a further significant peak on ECA 1. Using a single-step approach with a combined relationship matrix, the estimated heritability for withers height was 0.31 (SE = 0.08) and the corresponding genomic breeding values ranged from - 2.94 to 2.96 cm. A mean reliability of 0.38 was realized for these breeding values. The analyses of withers height showed that compiling a reference population across breeds is a suitable strategy for German Warmblood horses. The single-step method is an appealing approach for practical genomic prediction in horses, because not many genotypes are available yet and animals without genotypes can by this way directly contribute to the estimation system.

[Prevalence of health problems in midlife Swiss warm-blooded horses]. / Auftreten gesundheitlicher Probleme beim Schweizer Warmblutpferd ­mittleren Alters.

INTRODUCTION: The breeding of a healthy horse is the basic requirement for optimal performance. This is also specifically stated in the breeding goal of the Swiss warmblood horse and should be achieved through a strict selection of the stallions. The aim of this retrospective study was to assess the current state of the population to optimize breeding. Data on the health status of Swiss warmblood horses in the age between 6 and 16 years (midlife) were collected by a telephone survey and analyzed descriptively. Following the heritability of the most common health problems were estimated. Data on 1,861 horses were collected between 2016 and 2018. Lameness (34%), colic (22%), sarcoids (19%), and pastern dermatitis (16%) were among the most common health problems, followed by back problems (13%), cough (10%), urticaria (10%), free fecal water syndrome (9%), nasal discharge (8%) and sweet itch (4%). Lameness was observed in 49% of the cases in the forelimbs, in 25% in the hindlimbs and in 26% in both. 27% of horses with colic have been hospitalized once and 8% have undergone colic surgery. Sarcoids became fewer or smaller in 89% of the treated and in 58% of the untreated horses. A significant relationship between treatment and the status of the sarcoids was demonstrated (p .

INTRODUCTION: L'élevage d'un cheval en bonne santé représente une condition de base pour une performance optimale. Ceci est également spécifiquement mentionné dans l'objectif d'élevage du cheval de sang suisse et doit être atteint par une sélection stricte des étalons. Afin d'optimiser l'élevage, il faut connaître l'état actuel de la population, ce qui était le but de cette étude rétrospective. Au moyen d'une enquête téléphonique, des données sur l'état de santé des chevaux de sang suisses âgés de 6 à 16 ans (âge moyen) ont été collectées et traitées de manière descriptive. Les héritabilités des problèmes de santé les plus courants ont ensuite été estimées. Au total, les données de1861 chevaux ont été collectés entre 2016 et 2018. Les boiteries (34%), les coliques (22%), les sarcoïdes (19%) et les crevasses (16%) figuraient parmi les problèmes de santé les plus courants, suivis des problèmes de dos (13%), de la toux (10%), des urticaires (10%), d'écoulements anaux (« Kotwasser ¼) (9%), d'écoulements nasaux (8%) et de dermite estivale (4%). Chez 49% des chevaux boiteux, il s'agissait d'une boiterie antérieure, chez 25% d'une boiterie postérieure et chez 26% d'une boiterie impliquant antérieurs et postérieurs. 27% des chevaux présentant des coliques avaient été hospitalisés et 8% avaient subi une chirurgie de coliques. Les sarcoïdes sont devenus moins nombreux ou plus petits chez 89% des chevaux traités mais également chez 58% des chevaux non traités. Une relation significative entre le traitement et l'état des sarcoïdes a pu être démontrée (p .

Genetic Characterization of Mangalarga Marchador Breed Horses Based on Microsatellite Molecular Markers.

The Mangalarga Marchador (MM) horse breed has expressive importance in the Brazilian economy. Thus, the aim of this study was to investigate diversity in the MM breed. A database with a total of 3,193 genotyped horses was used (MM, n = 2,829; Andalusian - AND, n = 67; Pure Blood Lusitano - LUS, n = 43; English Thoroughbred - THO, n = 54; Arabian - ARA, n = 99; Campolina - CAM, n = 61; and Mangalarga - MAN, n = 40) for 13 microsatellite. Diversity parameters were estimates, such as mean number of alleles (Nma) and the number of rare alleles (AR), expected heterozygosity (He), F statistics, genetic distances, Hardy-Weinberg equilibrium test (HWE), population structure, and others. The Nma was 10.85, the AR was prevalent in the MM, and the He was 0.7402. In MM, the values of Fis (-0.0195), Fit (0.0566), Fst (0.0748), and deviations of HWE were observed. The genetic distances of the ARA and THO breeds with the other breeds were greater than the distances between the Brazilian breeds and between these and the breeds in the Iberian Peninsula. The population structure indicated that MM was substructured, yet there were some more genetically defined breeding farms. The genetic diversity is satisfactory for MM conservation, but the population is substructure, and parameters indicate moderate gene flow and the existence, though few, of crosses with other horse breeds. Immediate implementation of a genetic breeding program is required, especially seeking to conserve the structure of the MM breed as a well-defined genetic entity.

Cost-effective horse breeding in the Republic of Bashkortostan, Russia.

BACKGROUND AND AIM: There is a lack of reliable data in agribusiness regarding the economic efficiency of horse breeding, and this limits its further development. The purpose of this study was to create rational parameters for the development of productive horse breeding as an effective agricultural business, in particular, in relation to farms. MATERIALS AND METHODS: The methods of investigation used were induction and deduction, as well as analytical, statistical, and economic-mathematical analysis. We also used the dynamics of time series, CVP analysis, direct costing, and microeconomic analysis. Data were taken from the Russian Federation's official statistics on animal husbandry as well as closed (commercial) data of agricultural enterprises from our study region. RESULTS: Horse ownership in the Republic of Bashkortostan is higher than in the rest of Russia with about 9% of the total number of horses in Russia. We found that landowners need one hectare of arable land to ensure profit and that the highest economic income occurs on farms specializing in kumis production. The production of kumis under intensive farming is less profitable than with free-range horses kept in pastures. Family farms need a large amount of arable land with natural foliage to balance space and profit. CONCLUSION: Successful implementation of these parameters will make it possible to turn agriculture into successful horse breeding businesses. The expected volume of agricultural production may be approximately 9-11 thousand US dollars per employee.

Frequency of gastrointestinal parasites in Creole horses from the Southern Rio Grande do Sul / Frequência de parasitos gastrintestinais em equinos da raça Crioula do sul do Rio Grande do Sul

A criação de equinos brasileira movimenta anualmente cerca de R$ 16,15 bilhões e impulsiona o setor econômico primário do país. O mercado de animais da raça Crioula vem se expandindo devido ao seu alto potencial zootécnico. No Rio Grande do Sul, a criação é tipicamente extensiva, aliada, muitas vezes, à alta densidade animal, o que favorece as constantes infecções por diversos parasitos. O objetivo deste estudo foi analisar retrospectivamente a frequência de parasitos gastrointestinais em cavalos da raça Crioula naturalmente infectados na região sul do Rio Grande do Sul. Foram utilizadas 585 amostras de fezes de equinos da raça Crioula, adultos, de ambos os sexos, recebidas de criatórios e centros reprodutivos localizados na região. Do total de amostras, 89,74% (525/585) foram positivas para algum helminto. Em 57,60% (337/585) das amostras, observaram-se somente ovos da família Strongylidae. Infecções por Parascaris spp. e Strongyloides sp., apresentaram frequências de 2,22% (13/585) e 1,53% (9/585), respectivamente. Assim, pode-se concluir que os parasitos mais frequentes na população equina da região sul do RS pertencem à família Strongylidae.(AU)

Reproductive Characteristics of Thawed Stallion Sperm.

The main goal of our study was to determine a set of thawed stallion sperm characteristics that have predictive value for the pregnancy rate (PR) of mares after artificial insemination (AI). DNA fragmentation and survival of sperm during hypothermic storage were studied in addition to routinely determined semen characteristics such as concentration, percentage of motile spermatozoa, and morphology. To estimate DNA fragmentation, a modified hallo assay was applied. Sperm survival was determined within hours as the ability of spermatozoa to maintain progressive motility (PM) during the storage of ejaculate diluted with lactose-chelate-citrate-yolk (LCCY) medium at +4 °C. Strong positive correlation between PR and thawed sperm motility (r = 0.90, p < 0.05) as well as between PR and sperm survival (r = 084, p < 0.05) was revealed. There was also a strong negative correlation between PR and DNA damages in spermatozoa (r = -0.94, p < 0.05). We found no dependence of PR on normal morphology spermatozoa percentage in thawed semen. We concluded that the sperm activity, survival, and DNA fragmentation should be considered as the sufficient reproductive characteristics of semen to evaluate the quality of frozen/thawed sperm and prediction of PR.

Genetic diversity and population structure of Polish Arabian horses assessed through breeding and microsatellite data.

Polish Arabian horses are one of the most important populations of this breed in the world. Their post-war history can be divided into two periods, with the dominant role of state studs until 1989, and the increasing significance of private breeding in the next years. The goal of the study was to evaluate genetic diversity and structure of the population under a new breeding policy. The analyses of breeding and microsatellite data from 1996 to 2012 provide a coherent picture of the population with constant flow of horses only in one direction from state to private studs. An increase in the number of broodmares was observed, from 396 mares in 1996 to 1021 mares in 2012. The proportion of foreign sires used in Polish studs also increased, from 7.1% to 37.0%. An increasing number of alleles and progressive differentiation in mares were observed. STRUCTURE analysis indicated that the Polish horses were clearly separated from foreign horses used in Polish breeding, although only one of the 75 alleles found can be considered as typically Polish. The high heterozygosity is an important feature of the Polish population; however, the decrease of heterozygosity in state broodmares was noted. This issue needs to be studied further.

[Historic treasures of Swiss horse breeding]. / Historische Preziosen der Schweizer Pferdezucht.

INTRODUCTION: Both a mandate of the Bernese Government (1705) and statements in the Georgica Helvetica of 1706 prove that Swiss horse breeding was lucrative and of good quality at that time. However, the political turmoil at the transition from the 18th to 19th century and excessive sales to France and Italy led to a severe drop in quantity as well in quality. The exhibition of horses in Aarau in 1865 showed a wretched state of the material. In the same year, Rudolf Zangger wrote a guide for the discussion of horse breeding in Switzerland. In the following year (1866), Johann Jakob Rychner published a report on horse breeding, and a further treatise on Swiss horse breeding by Johann Heinrich Hirzel followed in 1883. These publications created good and comprehensive fundamentals, which can still be considered valid. However history shows that the results and recommendations of these analyses barely led to improvements. Todays genomics with their possibilities open up a new era of animal breeding and raise bigger demands than ever.

Un mandat du gouvernement bernois de 1705 et les explications de Georgica helvetica de 1706 nous montrent la bonne qualité et la valeur économique de l'élevage chevalin de l'époque. Les troubles politiques à la fin du 18ème siècle et les exportations d'un nombre trop élevé de chevaux vers la France et l'Italie ont eu comme conséquence une perte de la valeur génétique et une diminution du nombre des chevaux. L'exposition chevaline de Aarau en 1865 a montré un triste état de la situation. Pendant la même année, Rudolf Zangger a publié des réflexions sur l'élevage chevalin en Suisse et, une année plus tard, Johann Jakob Rychner en faisait de même. En 1883, Johann Heinrich Hirzel a fait paraître ses propositions sur l'élevage chevalin. Aujourd'hui encore, le contenu de ces publications peut être considéré comme actuel. Une rétrospective montre que ces analyses et les propositions d'améliorations n'ont eu que peu de résultats. Les possibilités actuelles de la génomique ouvrent une nouvelle ère pour l'élevage et représentent un vrai défi pour l'avenir.

Genetic Variability of Show Jumping Attributes in Young Horses Commencing Competing.

The aim of the study was to select traits that may constitute a prospective criterion for breeding value prediction of young horses. The results of 1,232 starts of 894 four-, five-, six-, and seven-year-old horses, obtained during jumping championships for young horses which had not been evaluated in, alternative to championships, training centres were analyed. Nine traits were chosen of those recorded: ranking in the championship, elimination (y/n), conformation, rating of style on day one, two, and three, and penalty points on day one, two, and three of a championship. (Co)variance components were estimated via the Gibbs sampling procedure and adequate (co)variance component ratios were calculated. Statistical classifications were trait dependent but all fitted random additive genetic and permanent environment effects. It was found that such characteristics as penalty points and jumping style are potential indicators of jumping ability, and the genetic variability of the traits was within the range of 14% to 27%. Given the low genetic correlations between the conformation and other results achieved on the parkour, the relevance of assessment of conformation in four-years-old horses has been questioned.

Caracterização da equideocultura no estado de Minas Gerais / Characterization of equidae breeding in Minas Gerais state

Recently, horse breeding has achieved greater prominence in the Brazilian society and now it started to appear as a part of the Brazilian agribusiness. The state of Minas Gerais stands out as the main producer of equidae in Brazil. The aim of this work was to characterize the breeding of equidae in this State in order to support future researches in this sector. By the evaluation of records from 1990 to 2009 provided by the "Brazilian Institute of Geography and Statistics" (IBGE) and also 967 interviews with breeders of equidae, it was possible to characterize some important points. It was observed that equidae breeding in this State moves over R$1,500,000,000 per year and employs 86,000 people. The main investments of the properties are made in purchasing saddles, accessories and commercial feeds. The main goal of equidae breeders in Minas Gerais has been the work in rural properties (49.49%) complementing many farming activities, especially the work with cows. Although Minas Gerais holds the main herd of equidae in the country, the number of animals has decreased. On the one hand, the equidae breeding sector has demonstrated its social and economic importance in agribusiness; on the other, hand further researches are needed to develop public policies to improve the breeding of equidae in Minas Gerais.