Mountain Horse Research Articles

Association of Cartilage, Synovial Fluid and Membrane Pathological Findings in Serbian Mountain Horses Without Signs of Lameness

Abstract Osteoarthritis (OA) in horses often affects the metacarpal/metatarsophalangeal (MCP/MTP) joints and its detection in the early stages is crucial for effective management. I t was hypothesized that the extent of cartilage damage positively correlates with synovial membrane (SM) and synovial fluid (SF) pathological findings in the MCP/MTP joints of Serbian mountain horses that transported heavy loads but did not show signs of lameness. The study was conducted on 32 MCP/MTP joints of eight horses between seven to 12 years of age. Horse limbs were transferred from the abattoir to the necropsy room and SF was sampled. Its appearance, total nucleated cell count (TNCC), mononuclear cell count (MNC), total proteins (TP), and haptoglobin (Hp) were determined. Samples of SM were collected from the dorsal palmar/plantar pouch for histology. A macroscopic examination of gross condylar pathology of the third metacarpal/metatarsal bone was performed with Indian Ink staining. Scoring was done based on Osteoarthritis Research Society International recommendations. SF was clear, pale yellow, and mostly fairly viscous. Half of the samples had TNCC above, and all had TP within the reference range. Hp values were below the reference range and were omitted from further analyses. TNCC correlated with MNC (ρs=0.81, P<0.001), microscopic (ρs=0.62, P=0.003) and macroscopic scores (ρs=0.47, P=0.008). In addition, MNC correlated with macroscopic scores (ρs=0.40, P=0.03). All pathological findings were mild and their correlation indicated that these processes are interrelated and that could be ascribed to early OA.

VARIATION IN THE ASIP AND DUN GENES RESPONSIBLE FOR COAT COLOUR IN BOSNIAN MOUNTAIN HORSE

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.

Strangulation of the caecum by a pedunculated lipoma in a Rocky Mountain Horse gelding

SummaryA 19‐year‐old Rocky Mountain Horse gelding was presented for emergency evaluation of colic. A pedunculated lipoma was found to be strangulating the caecum and ileocaecal junction at surgery. Following the resolution of the incarceration, it was found that the pedicle originated on the jejunal mesentery, but the stalk did not appear long enough to have formed a half‐hitch around both the caecum and ileum. The horse was euthanised due to complete caecal devitalisation. A second pedunculated lipoma was identified at necropsy, located on the transverse colon with an area of ischaemia on the mesenteric pedicle (the abnormal stalk of tissue connecting the lipoma to the colonic mesentery), consistent with pressure from being entwined with the jejunal mesenteric pedicle. This report is the first to describe caecal and ileal incarceration and strangulation by a pedunculated lipoma in a horse.

Changes during lactation in the mineral element content of mare milk produced in semi-extensive rural farms

This study characterizes, for the first time, the content of individual mineral elements in mare milk from Basque Mountain Horse breed, as well as changes that occur during lactation and among semi-extensive rural farms. Individual milk samples from eighteen mares belonging to three commercial farms were collected along six months of lactation, and the contents of eleven mineral elements in milk were determined using a triple quadrupole inductively coupled plasma mass spectrometer (ICP-MS). Basque Mountain Horse milk contained calcium (Ca; 958 ± 248 μg/g milk), potassium (K; 581 ± 117 μg/g milk), phosphorus (P; 454 ± 160 μg/g milk), sodium (Na; 141 ± 38 μg/g milk), magnesium (Mg; 64.1 ± 15.7 μg/g milk), zinc (Zn; 2.50 ± 0.88 μg/g milk) and copper (Cu; 0.343 ± 0.179 μg/g milk) amounts similar to those reported in other horse breeds. Conversely, low sulphur (S; 156 ± 42 μg/g milk) and chlorine (Cl; 49.3 ± 33.4 μg/g milk), and high iron (Fe; 2.43 ± 2.44 μg/g milk) contents were found. Mn was only quantifiable in 12% of the samples. The content of all macrominerals, except Na and Cl, decreased at the end of lactation, while that of trace elements (Zn, Cu and Fe) either increased or fluctuated. In addition, the content of Ca, P, S and Na differed significantly among semi-extensive rural farms, probably due to differences in feeding management. From a multivariate perspective, the mineral element composition of the milk made it possible to differentiate samples from early, mid and late lactation stage.

Matrilineal Composition of the Reconstructed Stock of the Szekler Horse Breed

The Szekler horse was a small-sized mountain horse of the Carpathian Mountains whose official stud book ceased to exist after WWII. Despite that, individual horses preserving all the characteristics of the Szekler horse remained scattered in remote areas. This study aims to evaluate the mitochondrial D-loop sequence (608 bp) of the founder population (n = 59) in 2021 of a breed reconstruction project started in 2012. D-loop showed 68 polymorphic sites. The number of haplotypes was 34, with haplotype diversity (Hd) 0.966 and nucleotide diversity (π) 0.02232. The value of Fu’s Fs statistic (−6.566) was significant (p < 0.001), which rejects a stable population status. Thirteen haplogroups (HG) were found with a nearly equal number of representatives (HG(n)—A (5), D (1), E (2), G (4), I (4), J–K (1), M (4), N (2), O’P (4), and R (1)). In contrast, the Q, L, and B HGs occurred in more horses (15, 9, and 7, respectively). Based on a large number of polymorphic sites and haplotypes, the founder stock is considered diverse. Since the HG Q is characteristic of Asian horses, the examined stock haplotype distribution reflects the eastern origin of the Hungarian horses brought from the East in 896 AD. It is complemented by the gene pool of horses from Europe (e.g., L) and the Middle East (e.g., B).

Breed Distribution and Allele Frequencies of Base Coat Color, Dilution, and White Patterning Variants across 28 Horse Breeds.

Since domestication, horses have been selectively bred for various coat colors and white spotting patterns. To investigate breed distribution, allele frequencies, and potential lethal variants for recommendations on genetic testing, 29 variants within 14 genes were investigated in 11,281 horses from 28 breeds. The recessive chestnut ea allele in melanocortin 1 receptor (MC1R) (p.D84N) was identified in four breeds: Knabstrupper, Paint Horse, Percheron, and Quarter Horse. After filtering for relatedness, ea allele frequency in Knabstruppers was estimated at 0.035, thus illustrating the importance of testing for mate selection for base coat color. The Rocky Mountain Horse breed had the highest allele frequency for two of the dilution variants under investigation (Za.f. = 0.32 and Cha.f. = 0.026); marker-assisted selection in this breed could aid in the production of horses with desirable dilute coats with less severe ocular anomalies caused by the silver (Z) allele. With regard to white patterning, nine horses homozygous for the paired box 3 (PAX3) splashed white 2 (SW2) allele (p.C70Y) and six horses homozygous for the KIT proto-oncogene, receptor tyrosine kinase (KIT) sabino 1 (SB1) allele (ECA3g.79544206A>T) were identified, thus determining they are rare and confirming that homozygosity for SW2 is not embryonic lethal. The KIT dominant white 20 (W20) allele (p.R682H) was identified in all but three breeds: Arabian (n = 151), Icelandic Horse (n = 66), and Norwegian Fjord Horse (n = 90). The role of W20 in pigmentation across breeds is not well understood; given the different selection regimes of the breeds investigated, these data provide justification for further evaluating the functional role of this allele in pigmentation. Here, we present the largest dataset reported for coat color variants in horses to date, and these data highlight the importance of breed-specific studies to inform on the proper use of marker-assisted selection and to develop hypotheses related to pigmentation for further testing in horses.

Possibilities of horse-breeding sustainable development

Up until the middle of the 20th Century equine breeding was considered an industry that directly reflected the national wealth and status of any given country. Since then, due to the upheaval of mechanisation the number of horses gradually declined, primarily in Europe. The recorded declining numbers concerning draft horse breeds are particularly alarming, in comparison to breeds used for sport and recreation which have increased notably during the last thirty years or so. Thus it can also be remarked how the numbers and quality of horses in many European countries like Slovenia and Croatia had improved noticeably. However, in Bosnia and Herzegovina, horse breeding practices continue to deteriorate: the numbers of these magnificent creatures plummet progressively. Former state stud farms are being shut down and the once abundant population of autochthonous Bosnian mountain horses have reached a breaking point. The Arab, Lipizzan and cold blooded horse breeds have met a similar fate. Despite that, horses do hold an important position in the folk traditions of Bosnia and Herzegovina, especially with the people of the Republic of Srpska. The people cherish numerous traditions in relation to these animals and genuinely care for horses, which is how and why the horse breeding industry lives on - nurtured by the enthusiasm of individuals. Equine breeding is not economically unsustainable, on the contrary, its economical significance is in fact great in developed countries. Sustainable development possibilities can be sought in equestrian sports certainly, but also in tourism, recreational practices, hippotherapy, landscape maintenance (pastures), the production of mare milk, etc. Observing the economic potential of the equine industry which includes trade and consumerism, employment opportunities, food production, the related pharmaceutical and equestrian equipment industry, as well as services, it becomes clear that it’s in the absolute interest of the state to stop and reverse the negative horse breeding trend. Moreover, it is essential to keep in mind that the preservation of the autochthonous horse breeds and stud farms, developed throughout the decades, is beneficial not only for the obvious economic reasons, but for the sake of heritage and culture, as well as the conservation of folkcustoms and traditional values in general. The autochthonous horse breeds could be used in all of these areas. This effort, the conservation of autochthonous genetic resources, requires state support. With the support of the state, by promoting professional equine breeding practices primarily in relation to selection and veterinary care, the decline of horse populations may be overturned which would consequently rehabilitate the horse breeding industry, and additionally contribute to the conservation of agrobiodiversity and autochthonous animal resources, environmental protection, and reverse the depopulation of rural municipalities through means of undeniable economic potential.

Serological Evidence of Common Equine Viral Infections in a Semi-Isolated, Unvaccinated Population of Hucul Horses.

Simple SummaryThe aim of the following research was an analysis of the occurrence of common equine viral infections in a Hucul herd, based on serological studies. This study provides epidemiological data concerning animals representing a semi-isolated herd, devoid of any specific prophylaxis. The obtained results provide a source of information on a primitive breed of horses, as well as giving an insight into viruses (among them, arboviruses) circulating within a local ecosystem.Huculs (Equus caballus) are an old breed of primitive mountain horses, originating from the Carpathian Mountains. To the best of our knowledge, data concerning the epidemiology of viral infections observed within this breed are sparse. The objective of this study was to estimate the serological status of a semi-isolated, unvaccinated Hucul herd, with respect to both common equine viral infections and horse-infecting arboviruses, the presence of which was previously reported in Poland. Twenty horses of the Hucul breed, living in a remote area in Poland, were studied in 2018 from March to May. Using nasal secretion swabs as a specimen source, isolation attempts were negative regarding ERAV, EHV-1, EAV, and EIV. According to the virus neutralisation method, in the sera obtained from the animals, antibodies against the following viruses were detected: EHV-1 in 12 horses (60%; with titres from 1:8 to 1:64), EIV A/H7N7 in 13 (65%; titres from 1:20 to 1:80), EIV A /H3N8 in 12 (60%; titres from 1:20 to 1:80), USUV in 5 (25%; titres from 1:10 to 1:80), and ERAV in 1 (5%; titre 1:32). Antibodies against EAV, EIAV, and WNV were not present in the tested sera. The detected presence of specific antibodies associated with five out of the eight equine viruses investigated indicates that the Hucul herd, due to its partial separation and lack of specific prophylaxis, could serve as a sentinel animal group for the detection of equine viruses/arboviruses present within the local ecosystem. The detection of common equine viral infections within the herd provides additional epidemiological data concerning the breed.

AUTOCHTHONOUS BREEDS OF DOMESTIC ANIMALS AND CONSERVATION MEASURES

Recently, highly productive breeds of various species of domestic animals have been used in livestock production, which has resulted in the destruction of indigenous breeds of domestic animals around the world, even in our area. This is the first reason why indigenous races and strains have been endangered. Another reason is that domestic, indigenous breeds were crossed with specialized breeds, which were imported, and in that way their genetic diversity was negatively affected. Resistance is lost, adaptation to the conditions in which they were created, the ability to survive in nature. Indigenous breeds of different species of domestic animals, which are recognized in the Republic of Srpska (BiH) are gatačko cattle and buša (cattle), Vlašić pramenka, Podveleška pramenka, Kupres pramenka (sheep), domestic Balkan horned goat (goats), Bosnian mountain horse (horses), mangulica (pigs) and pogrmuša hen or živičarka hen (poultry). By acceding to international conventions, BiH /Republic of Srpska has committed itself to establishing a system of measures that will enable the conservation of biological diversity and the protection of indigenous and endangered breeds of domestic animals. The choice of a strategy for the conservation of diversity, the establishment of an adequate conservation scheme, and the implementation of a conservation strategy are some of the key elements of any process for the conservation of genetic diversity. Preservation of autochthonous and protected breeds of domestic animals is possible through preservation in the original environment (in situ) and preservation outside the original environment (ex situ). There is a possibility of combining these models of conservation of animal genetic resources.

Evaluation of the genetic diversity and population structure of potential Bosnian mountain horse based on microsatellite markers

The focus of this study was to evaluate the genetic diversity and population structure of potential Bosnian mountain horse and todetermine the possible sources of undoubtedly autochthonous germplasm using microsatellite markers. Genomic DNA was extracted from the whole blood collected from 61 potential Bosnian mountain horse specimens divided into three groups according to the population of origin and genotyped by using 17 specific microsatellite markers. Existence of higher genetic variability was obtained in Group 1 and 3. Group 2 showed genetic specificity as well as high level of heterogeneity. An increased inbreeding coefficient was detected in Group 1 and 3 (0.1678 and 0.1813, respectively). Deviation from HardyWeinberg equilibrium was noticed in Group 1 and 3. Analysis of molecular variance showed that from all genetic variation, 5% was among populations, 14% among individuals and 81% within individuals. Results of the fixation index showed moderate level of genetic differentiation among groups (5.1%). The results of pairwise differences showed clear genetic differentiation among Group 2 and other observed groups. Analyses of admixture model showed that second cluster consist almost all individuals from Group 2, since other clusters consists individuals from two other observed groups. Factorial Component Analysis has confirmed results of admixture model. Group 2 has indications the most genetically characteristics of autochthonous Bosnian mountain horses. Results of genetic diversity and F statistic data indicate that in the gene pool of Group 1 and 3 is present a part of the gene pool of other breeds.

DDB2 Genetic Risk Factor for Ocular Squamous Cell Carcinoma Identified in Three Additional Horse Breeds.

Squamous cell carcinoma (SCC) is the most common cancer affecting the equine eye. A missense variant within the gene damage-specific DNA binding protein 2 (DDB2 c.1013C>T, p.Thr338Met) was previously identified as a causal recessive genetic risk factor for the development of ocular SCC within Haflingers, Belgian Draft horses, and Rocky Mountain Horses, but not in the Appaloosa or Arabian breeds. This study aimed to evaluate three cases of ocular SCC in additional breeds and determine if DNA testing for the DDB2 variant in warmblood horses and Connemara ponies is warranted. Histopathology confirmed ocular SCC in all three cases and DNA testing confirmed each horse was homozygous for the DDB2 risk factor. The DDB2 risk allele frequency was estimated to be 0.0043 for Holsteiners (N = 115), 0.014 for Belgian Warmbloods (N = 71), and 0.22 for Connemara Ponies (N = 86). Taken together these data support using DNA testing for DDB2 in Connemara Ponies to assist in mate selection and clinical management. Given the low observed allele frequencies in both the Holsteiner and Belgian Warmblood breeds and that the case under investigation was a warmblood cross-bred, evaluating additional SCC affected warmbloods is warranted to fully determine the importance of DDB2 genotyping as a risk factor in warmblood breeds.

A novel DDB2 mutation causes defective recognition of UV-induced DNA damages and prevalent equine squamous cell carcinoma

Squamous cell carcinoma (SCC) occurs frequently in the human Xeroderma Pigmentosum (XP) syndrome and is characterized by deficient UV-damage repair. SCC is the most common equine ocular cancer and the only associated genetic risk factor is a UV-damage repair protein. Specifically, a missense mutation in horse DDB2 (T338M) was strongly associated with both limbal SCC and third eyelid SCC in three breeds of horses (Halflinger, Belgian, and Rocky Mountain Horses) and was hypothesized to impair binding to UV-damaged DNA. Here, we investigate DDB2-T338M mutant’s capacity to recognize UV lesions in vitro and in vivo, together with human XP mutants DDB2-R273H and -K244E. We show that the recombinant DDB2-T338M assembles with DDB1, but fails to show any detectable binding to DNA substrates with or without UV lesions, due to a potential structural disruption of the rigid DNA recognition β-loop. Consistently, we demonstrate that the cellular DDB2-T338M is defective in its recruitment to focally radiated DNA damages, and in its access to chromatin. Thus, we provide direct functional evidence indicating the DDB2-T338M recapitulates molecular defects of human XP mutants, and is the causal loss-of-function allele that gives rise to equine ocular SCCs. Our findings shed new light on the mechanism of DNA recognition by UV-DDB and on the initiation of ocular malignancy.

Proshloe, nastoyashchee i budushchee kyrgyzskoj loshadi

The Kyrgyz horse is one of the oldest animal species. This is confirmed by the materials and statements of scientists-ethnographers, which were based on the works of historiographers and the results of archaeological excavations. Genetic research once again testifies to the long evolution and four thousand-year Genesis of this type of horse. The native Kyrgyz horse is a unique type of mountain horse that has a distinctive population feature, formed by centuries-old folk selection and under the strong influence of natural and climatic conditions in the process of natural selection. Historical sketches of the past centuries testify to the merits and identity of the Kyrgyz horse. Their numbers are limited, and the risk of extinction of native animals as an element of biodiversity will greatly affect human wellbeing in the present and future, especially a serious negative impact on the communities of mountain villages in the country.

A Primitive Trait in Two Breeds of Equus Caballus Revealed by Comparative Anatomy of the Distal Limb.

Simple SummaryUnderstanding the complexities and evolutionary links between extinct and extant equids has been vital to genetic conservation and preservation of primitive traits. As domestication of the equid expanded, the loss of primitive traits that ensured survival in a wild environment has not been documented. In this study, the presence of functional interosseous muscle II and IV in the distal limb has been reported, and yet its existence could only be confirmed in relatives and two closely bred descendants of the extinct Tarpan. The morphology described was ligamentous in structure displaying clear longitudinal fibres with a skeletal origin and soft tissue insertion into the medial and lateral branches of the interosseous muscle III (suspensory ligament) dorsal to the sesamoids, similar in orientation to the flexor digitorum profundus ligamentum accessorium (inferior check ligament). Hence, providing a functional medial and lateral stability to the metacarpophalangeal joint (fetlock joint), which equates to one of the functions of the medial and lateral digits in the Mesohippus and Merychippus. The comparable anatomic links between species of the same family that experienced geographical isolation yet display structural conformity appears to be in response to a specific environment. Surmising this potential remnant of functional evolution is a primitive trait and not a breed anomaly.The 55-million-year history of equine phylogeny has been well-documented from the skeletal record; however, this is less true for the soft tissue structures that are now vestigial in modern horse. A recent study reported that two ligamentous structures resembling functional interosseous muscle II and IV were evident in Dutch Konik horses. The current study investigates this finding and compares it to members of the genus Equus to identify either a breed anomaly or functional primitive trait. Distal limbs (n = 574) were dissected from four species of Equus; E. caballus, E. asinus, E. przewalskii and E. quagga boehmi. E. caballus is represented by 18 breeds of horse, including the primitive Dutch Konik’. The interosseous muscle II and IV were evident in all four species, but only two breeds of E. caballus expressed this trait-the Dutch Konik and Bosnian Mountain Horse. These two breeds were the only close descendants of the extinct Equus ferus ferus (Tarpan) represented in this study. In conclusion, the interosseous muscle II and IV originated from the distal nodule of metacarpal II and IV, respectively, and inserted into the corresponding branches of interosseous muscle III proximal to the sesamoids. This suggests a functional role in medial and lateral joint stability and a primitive trait in modern equids.

DEFINING THE BREED STANDARDS AND BREEDING GOALS FOR DOMESTIC MOUNTAIN HORSE

Domestic mountain horse is a transpoundary breed present in many Balkan countries. According to the Low of Animal Production of R. of Macedonia from 2008, for every breed of domestic animal in our state is nessesery to create a separate breeding program. In 2013 in low of animal production the autohtonous breeds of equidaes are added two new varietes - domestic mountain horse and domestic donkey. Facing the obtained results from estimating the main morphological, reproductive and functional traits in 220 domestic mountain horses in central mountain part of Macedonia during 2015 and 2016, the current standards and breeding goals were defined for the next national breeding program of this breed. According to the fact that the domestic mountain horse is a metapopulation and transboundary breed of horse in almost all Balkan countries, it is a good recommendation to create a regional breeding program with flexible standards and breeding goals for this breed of horses for all Balkan countries together.

Usefulness of the 17-Plex STR kit for Bosnian mountain horse genotyping

In the present study modern technology of DNA extraction and automatic genotyping was applied in Bosnian and Herzegovinian autochthonous horse breed by using 17-Plex horse genotyping kit. The study was aimed at investigating usefulness of the 17-plex STR Kit for Bosnian mountain horse genotyping and establishing highly useful microsatellite markers system for genetic diversity studies in Bosnian mountain horse breed. Genomic DNA was extracted from whole blood collected from 22 unrelated Bosnian mountain horse specimens. A total of 95 alleles were detected. Average number of detected alleles per locus was 5.588, varying from 3 (HTG7) to 10 (ASB17). Average effective number of alleles was 3.603, fluctuating from 1.789 (HMS7) to 5.728 (HMS2). The observed heterozygosity ranged from 0.136 (HMS3) to 0.909 (ASB2) with a mean of 0.631. The results indicate that the studied population originates from the appropriate number of parent generations. The mean expected heterozygosity was 0.690, varying from 0.441 (HMS7) to 0.853 (ASB17) indicating high genetic variability within Bosnian mountain horse population. The PIC values ranged from 0.409 (HMS7) to 0.837 (ASB17) with a mean of 0.643, suggesting that 94.12% markers were quite informative in terms of their suitability for genetic diversity studies .The most polymorphic locus was HMS2 and the least polymorphic locus was HMS7. The inbreeding coefficient ranged from -0.030 (HMS7) to 0.807 (HMS3) with a mean of 0.077. Inbreeding coefficient values indicated no shortage of heterozygotes in Bosnian mountain horses. Deviation from Hardy-Weinberg equilibrium (p<0,05) was found in three loci (HTG10, HMS3 and ASB17). The applied set of 17 microsatellite markers proved to be sufficiently specific for use in genotyping of Bosnian mountain horse. Considering the values of HO, HEand PIC over 0.6, five microsatellite markers system (HTG4, AHT4, AHT5, ASB2, HMS2) is considered to be highly useful for genetic diversity studies in Bosnian mountain horse breed.

Historical aspects of breeding and preservation of Hutsul horse breed on the Ukrainian territory of the interwar Poland

The article examines the historical aspects of Hutsul horse breeding on Ukrainian territory of the interwar Poland. The unique breed of the Hutsul horse is an important component of the Ukrainian cultural and natural heritage. This horse breed was formed in the Carpathians historically, that is well adapted to the specifics of local environment, climatic and economic conditions. The purpose of this article is to study the complex of measures and practices taken by the Polish authorities and the indifferent people on the Ukrainian territory of the interwar Poland, in order to preserve and promote the Hutsul horse breeding. Despite the extremely unsatisfactory amount of the population of these mountain horses after the end of the First World War, in the next twenty years it has been possible to implement a number of measures that have contributed to the conservation of the breed, and an increase in the number of livestock. With the help of enthusiasts and state support, a horse-breeding factory was founded in Sudova Vishnia, where a number of selective stallion-breeders was formed, and the nursery station in the Carpathians restored its activity. Regular exhibitions and inspections of Hutsul horses motivated the co-owners to take proper care of their horses and facilitate the exchange of experience in their feeding. Until the beginning of the Second World War, a network of stud farms appeared in the Carpathians. Each of these farms had a stallion of Hutsul breed, and peasants could obtain grants for breeding and keeping horses. In 1925, the Union of Horse Hutsul breeds was established. This organization devoted its activities to the revival of the Hutsul horse breed, its cultivation and popularization among the population. The Union of Horse Hutsul breeds acted intensively before the Second World War. The efforts to scale up the number of Hutsul horses were not sufficient, but still it helped to maintain and increase the unique breed of Ukrainian mountain horses before the war. The experience of maintaining the breed and encouraging its breeding is an interesting subject for studying and comparing with modern practices in this area.

Runs of Homozygosity and Population History of Three Horse Breeds With Small Population Size

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.

Limbal squamous cell carcinoma in a Rocky Mountain Horse: Case report and investigation of genetic contribution

To document a case of limbal squamous cell carcinoma (SCC) in a Rocky Mountain Horse stallion determined to be homozygous for the genetic risk factor (DDB2 c.1013C>T) strongly associated with the disease in Haflinger and Belgian horses, and to determine the frequency of this allele in a larger population of Rocky Mountain Horses. One privately owned Rocky Mountain Horse and 84 Rocky Mountain Horses screened for allelic frequency. A complete ophthalmic examination was performed on a Rocky Mountain Horse stallion for assessment of a mass affecting the right eye. A clinical diagnosis of suspected limbal SCC was made, and routine keratoconjunctivectomy and adjunctive strontium irradiation were performed. Genotyping for the DDB2 c.1013C > T (rs1139682898) risk variant was performed utilizing an allele-specific PCR assay on DNA isolated from whole blood and hair follicles. Histopathology confirmed the limbal mass to be consistent with SCC. The horse was genotyped as homozygous for the DDB2 c.1013C >T risk variant. The frequency of the variant allele among a population of 84 Rocky Mountain Horses was found to be 0.20. The Rocky Mountain Horse breed possesses the DDB2 variant allele determined to be a significant risk factor for ocular SCC in the Haflinger and Belgian breeds. Genotyping additional Rocky Mountain Horses diagnosed with ocular SCC as well as confirmed healthy controls for this variant should be undertaken to determine whether a significant association exists between ocular SCC and the variant in the Rocky Mountain Horse breed.

Analysis of the State of Bosnian Mountain Horse in the Borike Stud Farm

In the last fifty years the number of horses in the Balkan Peninsula has been falling significantly, especially the Bosnian Mountain Horse. In B&amp;H there is a decreasing tendency in terms of the total number of horses as well as the extremely poor quality of racial composition. The most famous Balkan horse is the Bosnian Mountain Horse, which is the only indigenous breed in B&amp;H. The most comprehensive program for the conservation of the Bosnian Mountain Horse was carried out at the Borike stud farm (near Rogatica) founded in 1893. An empirical research was conducted through a survey with the Ministry of Agriculture, Forestry and Water Management of the Republic of Srpska. It is noted that the number of horses over the years has been constantly decreasing and that it is necessary to launch an action plan and to provide adequate measures designed to safeguard their future.