Within the Bosnian Mountain Horse Registry (BMH), some specific coat colours are permitted. Accurate determination of coat colours can be challenging as there are variations in coat colour shades and ...several dun dilution variants occur. The previously found single nucleotide polymorphisms (SNPs) within two coat colour loci, T-box 3 (TBX3) and Agouti Signalling Protein (ASIP), were genotyped in 313 BMH individuals. The obtained genotypes were then compared to the predicted phenotypes by using the observed coat colour types from the International Association of Bosnian Mountain Horse Breeders (IABMHB) database. It was found that the dark bay and black coat colours were the most representative coat colours both phenotypically and genotypically. The frequency of the dominant Dun (D) dilution allele is (0.09), and this frequency is higher than the previously predicted frequency recorded in the available BMH registers, as also demonstrated. Among the identified alleles, there was a discrepancy or inconsistency between the predicted coat colour based on genotypes and the observed coat colour in 73 horses (23%). The most frequent error concerned the misclassification of horses with genotypes aa and Aa at the ASIP gene, non-dun1/non-dun1 (nd1/nd1) and non-dun2/non-dun1 (nd1/nd2) at the TBX3 gene, which can be associated with the occurrence of slight dilution phenotypes in these individuals. In contrast to the Konik and Hucul breeds, no homozygosity of the D allele was found in the BMH. The D allele can be easily overlooked or not recognised in different phenotypic groups, such as dark bay and black horses. Therefore, the hypothesis that Dun dilution effects itself is not as strongly epistatic in the BMH as described in other horse breeds. This could be the result of an additional genetic modifier suppressing the phenotypic effect of the D allele. It also suggests that there has been a persistent selection pressure in favour of dark base colours, which may have contributed to the observed differences in BMH. Finally, a significant proportion (35%) of BMH individuals with genetically black coat colour were officially classified as dark bay. We hypothesise that the difficulty in visually distinguishing these two phenotypes is due to an independent locus upstream of the ASIP gene. This locus was recently identified as a factor that darkens the typical pigmentation in dark bay horses. The results of the study confirm the importance of molecular testing in accurately determining the coat colour of horses. This would help to avoid errors in coat colour descriptions in official breeding records and provide valuable information for selective breeding programmes aimed at producing specific and desired coat colours.
The aim of this study was to investigate the influences of sex and age on haematological values in the Posavje Horse breed. A total of 163 healthy Posavje horses (30 foals, 94 mares and 39 stallions) ...were used in this study; their complete blood counts and a leucogram were obtained with a haematological analyser. The horses were classified into five groups: foals (1 to 6 months, n = 30), 3 to 6 years (n = 8 stallions/21 mares), 7 to 9 years (n = 9 stallions/22 mares), 10 to 13 years (n = 8 stallions/20 mares), 14 to 15 years (n = 6 stallions/10 mares) and 16 and over (n = 8 stallions/21 mares). The results obtained show an influence of sex on haematological parameters, with red blood cell count (RBC), haematocrit (HCT) and haemoglobin concentration (HGB) being higher in stallions (P < 0.001) and white blood cell count (WBC) being higher in mares. Differences between the age groups of the Posavje horses examined indicate a decrease in RBC and HGB with a compensatory increase in mean corpuscular volume and mean corpuscular haemoglobin, a decrease in WBC and platelet counts (PLT) and proportion of lymphocytes, and an increase of neutrophil to lymphocyte ratio (N/L) with age (P < 0.001). Although the Posavje horse is classified as a draft horse breed, its haematological parameters show characteristics common to warm-blooded breeds, with the exception of the N/L ratio. One of the most important findings of this study is a higher neutrophil count in reproductively active breeding stallions. Higher levels of RBC, HGB, HCT and neutrophil count in the Posavje stallions suggest an effect of androgens (testosterone), which may be an effective mechanism to prevent infections, that can affect the survival of the stallions and thus the evolution of the species.
KARAKTERIZACIJA HEMATOLOŠKEGA PROFILA PRI POSAVSKEM KONJU
Izvleček: Cilj raziskave je bil proučiti vpliv spola in starosti na hematološke parametre pri pasmi posavski konj. V raziskavo je bilo vključenih 163 konj posavske pasme (30 žrebet, 94 kobil in 39 žrebcev), pri katerih smo v vzorcih krvi določali hematološke parametre s hematološkim analizatorjem. Diferencialna bela krvna slika in razmerje med nevtrofilci in limfociti (N/L) je bilo določeno na krvnih razmazih. Konje smo razdelili v pet starostnih skupin: žrebeta (od 1 do 6 mesecev, n = 30), 3 do 6 let (n = 8 žrebcev/21 kobil), 7 do 9 let (n = 9 žrebcev/22 kobil), 10 do 13 let (n = 9 žrebcev/20 kobil), 14 do 15 let (n = 6 žrebcev/10 kobil) ter 16 in več let (n = 8 žrebcev/21 kobil). Rezultati naše raziskave kažejo vpliv spola na preiskovane hematološke parametre; pri žrebcih so število rdečih krvnih celic (RBC), hematokrit (HCT) in koncentracija hemoglobina (HGB) značilno višji (P < 0,001), pri kobilah pa je višje število belih krvnih celic (WBC). Med starostnimi skupinami posavskih konj smo ugotovili zmanjšanje RBC in HGB in posledično kompenzacijo s povečanjem povprečnega volumna in hemoglobina eritrocitov, zmanjšanjem števila levkocitov, trombocitov (PLT) in limfocitov ter povečanjem razmerja med nevtrofilci in limfociti (N/L) s starostjo (P < 0,001). Posavski konj po zunanjosti spada med hladnokrvne konje, v raziskavi ugotovljeni hematološki profil pa kaže značilnosti, ki so skupne toplokrvnim pasmam konj, z izjemo razmerja N/L. Ena od pomembnejših ugotovitev te študije je večje število nevtrofilcev pri aktivnih plemenskih žrebcih. Višje vrednosti RBC, HGB, HCT in števila nevtrofilcev pri posavskih žrebcih kažejo učinek androgenov (testosterona), kar bi lahko bil učinkovit mehanizem za preprečevanje okužb, ki lahko vplivajo na preživetje žrebcev in s tem na evolucijo vrste.
Ključne besede: avtohtone pasme; posavski konj; hematologija; starost; spol
Different approaches and classification systems have been established to describe equine coat colour, which varies between breeds and countries. In the present study, we first characterised the coat ...colour variability in the Slovenian Posavje Horse applying colour spectrophotometry following the CIE L*a*b system. As derived from the classification system of Sponenberg (light bay, bay, mahogany bay, brown and seal brown), the phenotype categories could be confirmed by spectrophotometric data. Furthermore, L*a*b values revealed comparable high phenotypic variability of bay coat colour in the Posavje breed, and the darker shades of bay coat colour were associated with the ASIP and MC1R genotype combination A/a E/E. CIE L*a*b colour spectrophotometry represents an effective tool to characterise and quantify coat colour in horses, especially in chestnut horses, for which the underlying genetic background of coat colour variation remains unknown.Key words: Posavje Horse; MC1R; ASIP; coat colour; spectrophotometry; CIE L*a*b KARAKTERIZACIJA BARVE DLAKE PRI POSAVSKEM KONJU Izvleček: Za opis barv konj se uporabljajo različni pristopi in klasifikacijski sistemi, ki se razlikujejo med posameznimi pasmami in državami. V raziskavi smo najprej opredelili različne barve dlake pri posavskem konju z metodo barvne spektrofotometrije po sistemu CIE L*a*b*. Fenotipsko razdelitev barv dlake po Sponenbergu (light bay/svetli rjavec, bay/rjavec, mahogany bay/kostanjev, brown/temni rjavec and seal brown/črnkast rjavec) smo potrdili s spektrofotometričnimi podatki. Vrednosti L*a*b so pri posavskem konju pokazale primerljivo visoko fenotipsko variabilnost rjave barve, pri tem so bili temnejši odtenki povezani z ASIP in MC1R kombinacijo genotipa A/a E/E. Barvna spektrofotometrija po sistemu CIE L*a*b predstavlja učinkovito orodje za kvalitativno in kvantitativno opredelitev/določanje barv pri konjih, zlasti pri lisjakih, pri katerih še vedno ni znana genska osnova variabilnosti v barvi dlake.Ključne besede: posavski konj; MC1R; ASIP; barva dlake; spektrofotometrija; CIE L*a*b
Slovenian Cold-Blooded horse is an autochthonous horse breed in Slovenia, traditionally reared in the North-Eastern and Northern parts of Slovenia. Today the breed is widespread all over the country. ...Breeding program for the Slovenian Cold-Blooded horse was accepted 2005 when the Association of Slovenian Cold-Blooded Horse Breeders was established, too. The aim of the study was to analyse conformation and gaits traits of the Slovenian Cold-Blooded horse. Likewise, we tried to evaluate fixed effect, affecting the included traits. Data were collected during the classifications of Slovenian Cold-Blooded horse performed from 1996 to 2011. In this study, 1920 horses were included, 52 of which were stallions and 1868 mares. The scoring system included 8 measured and 10 scored traits. Data were analysed by GLM procedure of statistical package SAS/STAT considering sex, age at scoring and birth year as fixed effects. Stallions of Slovenian Cold-Blooded horses were on the average 152.4±0.56 cm high at withers (stick), while mares were 151.22±0.11 cm. Body length (stallions 163.95±1.48 cm; mares 164.28±0.17 cm) was on the average larger than the height at wither thus indicating the rectangular body frame.
Intensive artificial and natural selection have shaped substantial variation among European horse breeds. Whereas most equine selection signature studies employ divergent genetic population ...structures in order to derive specific inter-breed targets of selection, we screened a total of 1476 horses originating from 12 breeds for the loss of genetic diversity by runs of homozygosity (ROH) utilizing a 670,000 single nucleotide polymorphism (SNP) genotyping array. Overlapping homozygous regions (ROH islands) indicating signatures of selection were identified by breed and similarities/dissimilarities between populations were evaluated. In the entire dataset, 180 ROH islands were identified, whilst 100 islands were breed specific, all other overlapped in 36 genomic regions with at least one ROH island of another breed. Furthermore, two ROH hot spots were determined at horse chromosome 3 (ECA3) and ECA11. Besides the confirmation of previously documented target genes involved in selection for coat color (
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Posavje horse is an autochthonous horse breed in Slovenia as well as in Croatia. Slovenian population of Posavje horse is traditionally reared in the lower flow of the river Sava, in the surroundings ...of Krsko and Brezice. Breeding program for the Posavje horse was accepted in the year 2005 when the Slovenian Association of Posavje Horse Breeders was established, too. The aim of the study was to an
In the nineteenth and early twentieth century the Medžimurje horse played an important role as a draft and working horse in the river Mura region. Nowadays, this area is split between Hungary, ...Austria, Slovenia and Croatia. In the frame of the project "Management of traditional transboundary breeds on example of a nearly forgotten breed the Murinsulaner", we collected data for cold blooded horses similar to the Medžimurje horse. Horses of this type do not exist in Austria anymore, in Croatia they were registered as an authothonous breed »Medjimurje horse«, and in Slovenia and Hungary this horse has a special section in the stud book for cold blooded horses as a Medžimurje type of horse. The Slovenian part of the population of the Medžimurje horse is quite heterogeneous regarding body measures. With respect to the scoring system used in the above mentioned project, the majority of scored animals were classified as »desired« or »satisfactory«. In order to further develop or to preserve this type of horse or to form a consolidated breed we would have to make a breeding program which would prevent mating among related animals and to cooperate with neighbouring countries in the field of breeding and selection. The only hope to preserve this type of horse on the long term in the region is by using it as a tourist attraction for carriage riding and/or as a draft horse in agriculture in marginal regions.
In the nineteenth and early twentieth century the Medžimurje horse played an important role as a draft and working horse in the river Mura region. Nowadays, this area is split between Hungary, ...Austria, Slovenia and Croatia. In the frame of the project "Management of traditional transboundary breeds on example of a nearly forgotten breed the Murinsulaner", we collected data for cold blooded horses similar to the Medžimurje horse. Horses of this type do not exist in Austria anymore, in Croatia they were registered as an authothonous breed »Medjimurje horse«, and in Slovenia and Hungary this horse has a special section in the stud book for cold blooded horses as a Medžimurje type of horse. The Slovenian part of the population of the Medžimurje horse is quite heterogeneous regarding body measures. With respect to the scoring system used in the above mentioned project, the majority of scored animals were classified as »desired« or »satisfactory«. In order to further develop or to preserve this type of horse or to form a consolidated breed we would have to make a breeding program which would prevent mating among related animals and to cooperate with neighbouring countries in the field of breeding and selection. The only hope to preserve this type of horse on the long term in the region is by using it as a tourist attraction for carriage riding and/or as a draft horse in agriculture in marginal regions.
Medžimurski konj je imel pomembno vlogo pri transportu in delu v devetnajstem in v začetku dvajsetega stoletja na področju ob Muri. Danes je to področje razdeljeno med Madžarsko, Avstrijo, Slovenijo in Hrvaško. V okviru projekta "Upravljanje tradicionalnih čezmejnih pasem na primeru skoraj pozabljene pasme, medžimurski konj", smo zbrali podatke o hladnokrvnih konjih, ki so v tipu medžimurskega konja. V Avstriji takih konj ni več, na Hrvaškem so konje tega tipa registrirali kot avtohtono pasmo medjimurski konj, na Madžarskem in v Sloveniji pa se ti konji vodijo kot poseben oddelek (medžimurski tip) rodovniške knjige za hladnokrvne konje. Slovenski del populacije v tipu medžimurskega konja je glede na telesne mere precej neizenačen. Upoštevaje sistem ocenjevanja, ki je bil razvit v okviru omenjenega projekta, večina ocenjenih živali sodi v t.i. razred zaželeno oz. zadovoljivo. Za razvoj in ohranitev tega tipa konja oz. formiranje pasme, bo potrebno izdelati rejski program, ki bo zagotavljal preprečevanje parjenja v sorodstvu in razviti sodelovanje s sosednjimi državami na področju reje in selekcije tega tipa konj. Ne nazadnje je dolgoročen obstoj tega tipa konja mogoče zagotoviti le z njegovo uporabo za delo v kmetijstvu in v turizmu.
Abstract
Within the scope of current genetic diversity analyses, population structure and homozygosity measures are independently analyzed and interpreted. To enhance analytical power, we combined ...the visualization of recently described high-resolution population networks with runs of homozygosity (ROH). In this study, we demonstrate that this approach enabled us to reveal important aspects of the breeding history of the Haflinger horse. We collected high-density genotype information of 531 horses originating from 7 populations which were involved in the formation of the Haflinger, namely 32 Italian Haflingers, 78 Austrian Haflingers, 190 Noriker, 23 Bosnian Mountain Horses, 20 Gidran, 33 Shagya Arabians, and 155 Purebred Arabians. Model-based cluster analysis identified substructures within Purebred Arabian, Haflinger, and Noriker that reflected distinct genealogy (Purebred Arabian), geographic origin (Haflinger), and coat color patterns (Noriker). Analysis of ROH revealed that the 2 Arabian populations (Purebred and Shagya Arabians), Gidran and the Bosnian Mountain Horse had the highest genome proportion covered by ROH segments (306–397 Mb). The Noriker and the Austrian Haflinger showed the lowest ROH coverage (228, 282 Mb). Our combined visualization approach made it feasible to clearly identify outbred (admixture) and inbred (ROH segments) horses. Genomic inbreeding coefficients (FROH) ranged from 10.1% (Noriker) to 17.7% (Purebred Arabian). Finally it could be demonstrated, that the Austrian Haflinger sample has a lack of longer ROH segments and a deviating ROH spectrum, which is associated with past bottleneck events and the recent mating strategy favoring out-crosses within the breed.
Long consecutive homozygous genotype segments, runs of homozygosity (ROH), are a result of parents transmitting identical haplotypes, which can be used to estimate autozygosity. Based on 612K ...single-nucleotide polymorphisms, we computed three ROH parameters (genome length covered by ROH, SROH; number of ROH, NROH; and autozygosity, FROH) to investigate different scenarios in contemporary horse breeding: limited census (Bosnian mountain horse), conservation breeding (Posavje horse), and selection within closed studbook (Haflinger). The ROH parameters revealed well-defined differences between breeds. SROH was highest in the Bosnian mountain horse with 296.32 Mb, followed by the Haflinger sample (SROH = 270.35 Mb) and the Posavje sample with 192.68 Mb. The highest number of ROH segments (ROHs) was observed within the Haflinger sample followed by the Posavje sample. FROH ranged at a population level from 8.59% in Posavje, over the Haflinger (mean FROH = 12.05%) to 13.21% in the Bosnian mountain horse breed. Bottlenecks were detected for Bosnian mountain horse and Haflinger, whereas for the Posavje, a positive effect of the conservation breeding program was documented. Investigating the distribution of ROHs across the genome, we detected four common ROH islands on equine chromosomes ECA 6, ECA 11, and ECA 17, which were present in all breeds. On breed level, the Bosnian mountain horses contained 10, the Posavje, four, and the Haflinger, 11 distinct ROH islands (containing the MC1R locus on ECA 3). With this analysis, we were able to compare genomic levels of inbreeding between breeds differing in management, pedigree completeness, and genes under selection.
•ROHs firstly identified for the breeds Bosnian mountain horse, Posavje, and Slovenian Haflinger.•Characterisation of genomic inbreeding, bottleneck situations, and population history.•Detection of ROH islands, which suggest distinct genetic regions exposed to selection.•Comparison of inbreeding in breeds differing in pedigree length and population fragmentation.
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