Effects of sensor ear tags with twin pin fixing system on health and well-being of cattle.

INTRODUCTION: A sensor ear tag (SET) containing Global Positioning System (GPS), accelerometer, Radio-Frequency Identification (RFID), and Bluetooth technologies was tested for wearing comfort and compliance with animal welfare requirements in cattle in a free stall barn and on summer pasture in Switzerland. The SET was equipped with a long-lasting battery via solar panel and used a «twin pin¼ fixing system. Right ears of 12 newborns and 26 adolescent animals were tagged with the SET. While left ears were tagged simultaneously with official ear tags in newborns, the adolescent animals already carried the official ear tags. The newborns stayed in a free stall barn during the entire experiment, while adolescent animals were housed in a free stall barn and on pasture during summer. All animals developed crusts beginning on day 7 after tagging with the SET. Pain reactions were observed occasionally in the first two weeks. Ear growth in newborns during 11 months of observation did not differ between ears with SET and official ear tags. Cortisol concentration in saliva of newborns decreased in the first week after tagging which is physiological for this age group. In older animals cortisol concentrations in saliva were not affected. We registered 19 incidences in 11 animals with the SET, that required veterinary or staff intervention. Two animals lost the SET with ear injury. Scars due to tag migration were observed in ears of all newborns after the 9th month of observation. In conclusion, SET with a weight of 32 g that need a twin pin fixation in cows do not seem to induce systemic or local inflammations more frequently compared to official ear tags; however, the higher risk of accidental injuries and migration in ear cartilage would not meet Swiss welfare standards and the attachment to the ear needs to be improved for general use.

INTRODUCTION: Une marque auriculaire à capteur (SET) contenant les technologies Global Positioning System (GPS), accéléromètre, identification par radiofréquence (RFID) et Bluetooth a été testée en termes de confort et de conformité aux exigences de bien-être animal chez des bovins dans une étable à stabulation libre et sur des pâturages d'estivage en Suisse. Le SET était équipé d'une batterie longue durée via un panneau solaire et utilisait un système de fixation «twin pin¼. Les oreilles droites de 12 veaux et de 26 génisses ont été équipées avec le SET. Les oreilles gauches ont été marquées en même temps avec les marques officielles chez les nouveau-nés alors que les génisses portaient déjà ces marques officielles. Les nouveau-nés ont été détenu dans une étable à stabulation libre, avec accès à une aire de sortie et aux paturages voisins pendant toute la durée de l'expérience tandis que les génisses ont été logés dans une étable à stabulation libre et en pâturage pendant l'été. Tous les animaux ont développé des croûtes à partir du 7e jour après le marquage avec le SET. Des réactions douloureuses ont occasionnellement été observées au cours des deux premières semaines. La croissance des oreilles des nouveau-nés au cours des 11 mois d'observation n'a pas différé entre les oreilles marquées par le SET et les oreilles marquées de manière standard. La concentration de cortisol dans la salive des nouveau-nés a diminué au cours de la première semaine successive au marquage, ce qui est physiologique pour ce groupe d'âge. Chez les animaux plus âgés, les concentrations de cortisol dans la salive n'ont pas été affectées. Nous avons enregistré 19 incidents chez 11 animaux avec le SET, qui ont nécessité l'intervention d'un vétérinaire ou d'un membre du personnel. Deux animaux ont perdu le SET avec blessure à l'oreille. Des cicatrices dues à la migration des marques ont été observées sur les oreilles de tous les nouveau-nés après le 9e mois d'observation. En conclusion, les SET d'un poids de 32 g qui nécessitent une fixation par deux tiges chez les bovins ne semblent pas induire d'inflammations systémiques ou locales plus fréquemment que les marques auriculaires officielles. Cependant le risque plus élevé de blessures accidentelles et de migration dans le cartilage de l'oreille ne correspondrait pas aux normes suisses en matière de bien-être et la fixation à l'oreille doit être améliorée pour une utilisation généralisée.

[Spatial accessibility to animal health care - a GIS based analysis]. / Räumliche Zugänglichkeit zu tiermedizinischer Versorgung ­ eine GIS-basierte Analyse.

INTRODUCTION: Various studies from the past years examine the changing conditions and challenges in the veterinary sector. Secured access to public and private care services is a prerequisite for a holistically oriented health care system ("One Health"). In the present study, a multidimensional concept of accessibility to care services was used for the first time to determine and visualize the density of the animal health care system in Switzerland. Traditional indicators used to describe care structures focus either on availability or accessibility. In order to overcome the limitations of traditional indicators, the family of methods known as Floating-Catchment-Area-Methods (FCA) has been developed in care geographical research. The strength of FCA methods lies in the fact that they output accessibility independent of administrative boundaries and at the same time consider the spatial distance and available capacities. The study provides insight into the density of animal health care services using FCA methods and geographical information systems (GIS). Data on providers of veterinary services in the companion animal sector and, on the demand side, data on dogs and cats kept in Switzerland served as illustrative example. The result was interactive maps of the density of health care and the structure of spatial accessibility to veterinary providers and consumers. As expected, high spatial accessibility is found in the urban centers and the agglomerations of the Central Plateau. In contrast, spatial accessibility to medical services for dogs and cats is often lower in peripheral areas. Due to hitherto unavailable data, various analyses had to be postponed for the time being. For example, the model could of course be extended to all animal species and all types of medical services. In addition, it would also be possible to forecast the future density of health care, or to optimize the care system. Together with the relevant industry stakeholders, these gaps could be closed, and the model and the resulting findings could be further differentiated. The results should serve private actors in the concerned value chains, but also decision-makers in the public veterinary service, governmental authorities, agricultural bodies, universities, etc. as a basis for strategic decisions regarding the issue of medical supply density and care services in the animal sector.

INTRODUCTION: Ces dernières années, divers travaux ont examiné l'évolution des conditions cadres et des défis dans le secteur vétérinaire. L'assurance d'un accès aux soins publics et privés est une condition préalable à un système de santé holistique (« One Health ¼). Dans le travail présent, on a tenté pour la première fois d'enregistrer et de visualiser la densité d'approvisionnement du système de soins vétérinaires en Suisse en utilisant un concept multidimensionnel d'accessibilité aux offres de soins. Les indicateurs traditionnels pour décrire les structures de soins se concentrent soit sur la disponibilité soit sur l'accessibilité. Afin de contrer les limites des indicateurs traditionnels, la famille de méthodes du Floating-Catchment-Area (FCA) s'est développée dans la recherche en géographie sanitaire. La force des méthodes FCA est qu'elles fournissent un accès indépendamment des limites administratives, tout en tenant compte de la distance spatiale et de la capacité disponible. Ce travail permet d'avoir un aperçu de la densité de l'offre vétérinaire en utilisant la méthodologie FCA en tenant compte de systèmes d'information géographique (SIG). Les données sur les prestataires de services vétérinaires dans le secteur des animaux de compagnie et sur la demande concernant les chiens et les chats vivant en Suisse ont servi d'exemple. Le résultat a été des cartes interactives de la densité de l'offre et de la structure de l'accessibilité spatiale aux prestataires vétérinaires et de celle des consommateurs. Comme prévu, il existe un degré élevé d'accessibilité spatiale dans les centres urbains et les agglomérations du plateau suisse. En revanche, l'accessibilité spatiale aux services vétérinaires pour chiens et chats est souvent plus basse dans les zones périphériques. En raison de données indisponibles précédemment, diverses analyses ont dû être abandonnées dans un premier temps. Ce modèle pourrait être étendu à toutes les espèces animales et aux diverses offres vétérinaires. En outre, il serait également possible de faire des prévisions sur la future densité de l'offre ou sur son optimisation. Conjointement avec les acteurs de la branche concernés, ces lacunes pourraient être comblées avec certitude et le modèle et les résultats qui en résulteraient seraient encore plus différenciés. Les résultats sont destinés à aider les acteurs privés dans les chaînes de valeur ajoutée, mais ils pourraient aussi servir de base aux décideurs des services vétérinaires publics, aux autorités d'exécution, aux organes de l'agriculture, aux universités, etc., pour prendre des décisions stratégiques autour du thème de la densité de l'offre médicale dans le secteur animal.

Comprehensive characterization of horse genome variation by whole-genome sequencing of 88 horses.

Whole-genome sequencing studies are vital to gain a thorough understanding of genomic variation. Here, we summarize the results of a whole-genome sequencing study comprising 88 horses and ponies from diverse breeds at 19.1× average coverage. The paired-end reads were mapped to the current EquCab3.0 horse reference genome assembly, and we identified approximately 23.5 million single nucleotide variants and 2.3 million short indel variants. Our dataset included at least 7 million variants that were not previously reported. On average, each individual horse genome carried ∼5.7 million single nucleotides and 0.8 million small indel variants with respect to the reference genome assembly. The variants were functionally annotated. We provide two examples for potentially deleterious recessive alleles that were identified in a heterozygous state in individual genome sequences. Appropriate management of such deleterious recessive alleles in horse breeding programs should help to improve fertility and reduce the prevalence of heritable diseases. This comprehensive dataset has been made publicly available, will represent a valuable resource for future horse genetic studies and supports the goal of accelerating the rates of genetic gain in domestic horse.

Asian horses deepen the MSY phylogeny.

Humans have shaped the population history of the horse ever since domestication about 5500 years ago. Comparative analyses of the Y chromosome can illuminate the paternal origin of modern horse breeds. This may also reveal different breeding strategies that led to the formation of extant breeds. Recently, a horse Y-chromosomal phylogeny of modern horses based on 1.46 Mb of the male-specific Y (MSY) was generated. We extended this dataset with 52 samples from five European, two American and seven Asian breeds. As in the previous study, almost all modern European horses fall into a crown group, connected via a few autochthonous Northern European lineages to the outgroup, the Przewalski's Horse. In total, we now distinguish 42 MSY haplotypes determined by 158 variants within domestic horses. Asian horses show much higher diversity than previously found in European breeds. The Asian breeds also introduce a deep split to the phylogeny, preliminarily dated to 5527 ± 872 years. We conclude that the deep splitting Asian Y haplotypes are remnants of a far more diverse ancient horse population, whose haplotypes were lost in other lineages.

A genome-wide association study for equine recurrent airway obstruction in European Warmblood horses reveals a suggestive new quantitative trait locus on chromosome 13.

Recurrent airway obstruction (RAO), also known as heaves, is an asthma-like respiratory disease. Its development is strongly influenced by environmental risk factors such as sensitization and exposure to moldy hay, straw bedding and stabling indoors. A hereditary component has been documented in previous studies; however, so far no causative genetic variant that influences the risk of developing RAO has been identified. In this study, we revised an existing dataset and selected 384 horses for genotyping on the Affymetrix high-density equine SNP array. We performed an allelic case-control genome-wide association study, which revealed a suggestively significant association on equine chromosome 13 at 32 843 309 bp. This SNP is located in the protein-coding gene TXNDC11, which is possibly involved in the folding process of the multiprotein complexes DUOX1 and DUOX2. In humans, these proteins are known to take part in regulating the production of H2 O2 in the respiratory tract epithelium as well as in MUC5AC mucin expression. Therefore, TXNDC11 may be considered a functional candidate gene, and further research is needed to explore its potential role in RAO-affected horses.

Genetic variability of the equine casein genes.

The casein genes are known to be highly variable in typical dairy species, such as cattle and goat, but the knowledge about equine casein genes is limited. Nevertheless, mare milk production and consumption is gaining importance because of its high nutritive value, use in naturopathy, and hypoallergenic properties with respect to cow milk protein allergies. In the current study, the open reading frames of the 4 casein genes CSN1S1 (αS1-casein), CSN2 (ß-casein), CSN1S2 (αS2-casein), and CSN3 (κ-casein) were resequenced in 253 horses of 14 breeds. The analysis revealed 21 nonsynonymous nucleotide exchanges, as well as 11 synonymous nucleotide exchanges, leading to a total of 31 putative protein isoforms predicted at the DNA level, 26 of which considered novel. Although the majority of the alleles need to be confirmed at the transcript and protein level, a preliminary nomenclature was established for the equine casein alleles.

Selection signatures in Shetland ponies.

Shetland ponies were selected for numerous traits including small stature, strength, hardiness and longevity. Despite the different selection criteria, Shetland ponies are well known for their small stature. We performed a selection signature analysis including genome-wide SNPs of 75 Shetland ponies and 76 large-sized horses. Based upon this dataset, we identified a selection signature on equine chromosome (ECA) 1 between 103.8 Mb and 108.5 Mb. A total of 33 annotated genes are located within this interval including the IGF1R gene at 104.2 Mb and the ADAMTS17 gene at 105.4 Mb. These two genes are well known to have a major impact on body height in numerous species including humans. Homozygosity mapping in the Shetland ponies identified a region with increased homozygosity between 107.4 Mb and 108.5 Mb. None of the annotated genes in this region have so far been associated with height. Thus, we cannot exclude the possibility that the identified selection signature on ECA1 is associated with some trait other than height, for which Shetland ponies were selected.

Genome-wide association studies based on sequence-derived genotypes reveal new QTL associated with conformation and performance traits in the Franches-Montagnes horse breed.

To identify novel quantitative trait loci (QTL) within horses, we performed genome-wide association studies (GWAS) based on sequence-level genotypes for conformation and performance traits in the Franches-Montagnes (FM) horse breed. Sequence-level genotypes of FM horses were derived by re-sequencing 30 key founders and imputing 50K data of genotyped horses. In total, we included 1077 FM horses genotyped for ~4 million SNPs and their respective de-regressed breeding values of the traits in the analysis. Based on this dataset, we identified a total of 14 QTL associated with 18 conformation traits and one performance trait. Therefore, our results suggest that the application of sequence-derived genotypes increases the power to identify novel QTL which were not identified previously based on 50K SNP chip data.

Two variants in the KIT gene as candidate causative mutations for a dominant white and a white spotting phenotype in the donkey.

White spotting phenotypes have been intensively studied in horses, and although similar phenotypes occur in the donkey, little is known about the molecular genetics underlying these patterns in donkeys. White spotting in donkeys can range from only a few white areas to almost complete depigmentation and is characterised by a loss of pigmentation usually progressing from a white spot in the hip area. Completely white-born donkeys are rare, and the phenotype is characterised by the complete absence of pigment resulting in pink skin and a white coat. A dominant mode of inheritance has been demonstrated for spotting in donkeys. Although the mode of inheritance for the completely white phenotype in donkeys is not clear, the phenotype shows similarities to dominant white in horses. As variants in the KIT gene are known to cause a range of white phenotypes in the horse, we investigated the KIT gene as a potential candidate gene for two phenotypes in the donkey, white spotting and white. A mutation analysis of all 21 KIT exons identified a missense variant in exon 4 (c.662A>C; p.Tyr221Ser) present only in a white-born donkey. A second variant affecting a splice donor site (c.1978+2T>A) was found exclusively in donkeys with white spotting. Both variants were absent in 24 solid-coloured controls. To the authors' knowledge, this is the first study investigating genetic mechanisms underlying white phenotypes in donkeys. Our results suggest that two independent KIT alleles are probably responsible for white spotting and white in donkeys.

Homozygous familial hypercholesterolemia (HoFH) in Germany: an epidemiological survey.

INTRODUCTION: In Europe a disease is recognized as rare if less than 1 in 2000 people suffer from the specific disease. In patients with familial homozygous hypercholesterolemia (HoFH) the accumulation of low-density lipoprotein cholesterol (LDL-C) leads to generalized atherosclerosis due to an insufficient functioning of the LDL-C receptors. Patients die early sometimes even in the mid-30s, from myocardial infarction or stroke. For the German population, insufficient epidemiological evidence exists. METHODS: A systematic literature search in EMBASE and Medline was performed in conjunction with a targeted manual search for epidemiological HoFH studies. Additionally a nationwide survey was conducted in Germany in all identified apheresis- and lipid centers. The purpose of the survey was the validation of the systematic literature search results based on empirical (practice) data. RESULTS: In total 961 publications were found, 874 were excluded based on pre-defined exclusion criteria leaving only 87 for further review. After review of the identified abstracts (n = 87) 23 publications were identified as epidemiological studies. Only one publication was found which reported a prevalence of 1:1,000,000. The qualitative survey among 187 physicians in Germany also revealed a low prevalence: 95 HoFH patients were identified in 35 centers. CONCLUSION: The estimated frequency of homozygous familial hypercholesterolemia patients in Germany is around 95 (1:860,000) and the disease should be recognized as rare according to the definition of the European Medical Agency.

[Clinical evaluation of the new coat colour macchiato in a male Franches-Montagnes horse]. / Klinische und genetische Befunde bei einem männlichen Freiberger mit der neuen Fellfarbe Macchiato.

In April 2008 a Franches-Montagnes colt was born with an unusual coat colour phenotype which had never been observed in that population before. The foal showed extended white markings on body and legs, a white head and blue eyes. As both parents have an unremarkable bay coat colour phenotype, a de novo mutation was expected in the offspring and a candidate gene approach revealed a spontaneous mutation in the microphthalmia associated transcription factor gene (MITF). A detailed clinical examination in 2010 indicated an impaired hearing capacity. As in the American Paint Horse large white facial markings in combination with blue eyes are associated with deafness, the hearing capacity of the stallion was closer examined performing brainstem auditory-evoked responses (BAER). The BAER confirmed bilateral deafness in the Franches-Montagnes colt. It is assumed that the deafness is caused by a melanocyte deficiency caused by the MITF gene mutation. Unfortunately, due to castration of the horse, the causal association between the mutation in the MITF gene and clinical findings cannot be confirmed by experimental matings.

Genetic evidence of subaortic stenosis in the Newfoundland dog.

Subaortic stenosis (SAS) is a cardiac disorder with a narrowing of the descending aorta below the left ventricular outflow tract of the heart. It occurs in several species and breeds. The Newfoundland is one of the dog breeds where it is more common and usually leads to death at early adulthood. It is still discussed to which extent SAS has a genetic background and what its mode of inheritance could be. Extensive pedigree data comprising more than 230,000 Newfoundland dogs from the European and North American population reaching back to the 19th century including 6023 dogs with a SAS diagnosis were analysed for genetic factors influencing SAS affection. The incidence and prevalence of SAS in the analysed Newfoundland population sample were much higher than those reported in previous studies on smaller population samples. Assuming that some SAS-affected dogs remained undiscovered or were not reported, these figures may even be underestimated. SAS-affected Newfoundland dogs were more often inbred and closer related to each other than unaffected dogs, which is an indicator for a genetic background of SAS. The sex had no significant impact on SAS affectedness, pointing at an autosomal inheritance. The only simple mode of inheritance that fitted the data well was autosomal codominant with lethal homozygosity and a penetrance of 1/3 in the heterozygotes.

Genetic diversity in an indigenous horse breed: implications for mating strategies and the control of future inbreeding.

The Franches-Montagnes is an indigenous Swiss horse breed, with approximately 2500 foalings per year. The stud book is closed, and no introgression from other horse breeds was conducted since 1998. Since 2006, breeding values for 43 different traits (conformation, performance and coat colour) are estimated with a best linear unbiased prediction (BLUP) multiple trait animal model. In this study, we evaluated the genetic diversity for the breeding population, considering the years from 2003 to 2008. Only horses with at least one progeny during that time span were included. Results were obtained based on pedigree information as well as from molecular markers. A series of software packages were screened to combine best the best linear unbiased prediction (BLUP) methodology with optimal genetic contribution theory. We looked for stallions with highest breeding values and lowest average relationship to the dam population. Breeding with such stallions is expected to lead to a selection gain, while lowering the future increase in inbreeding within the breed.

Pioneering fungi from the Damma glacier forefield in the Swiss Alps can promote granite weathering.

Fungi were isolated from fine granitic sediments, which were collected at 15 sampling points within a 20 m × 40 m area in front of the Damma glacier in the central Swiss Alps. From the 45 fungal isolates grown on nutrient-rich agar media at 4 °C, 24 isolates were selected for partial sequencing and identification based on the small subunit ribosomal DNA. Sequencing data revealed that the isolated fungi represented three fungal phyla and 15 species. The weathering potential of 10 of the 15 fungal species was tested with dissolution experiments using powdered granite material (<63 µm). The results showed that the zygomyceteous species Mucor hiemalis, Umbelopsis isabellina and Mortierella alpina dissolved the granite powder most efficiently due to the release of a variety of organic acids, mainly citrate, malate and oxalate. In particular, the high concentrations of Ca, Fe, Mg and Mn in the solutions clustered well with the high amounts of exuded citrate. This is the first report on fungi that were isolated from a non-vegetated glacier forefield in which the fungi's capabilities to dissolve granite minerals were examined.

Effective population size of an indigenous Swiss cattle breed estimated from linkage disequilibrium.

Effective population size is an important parameter for the assessment of genetic diversity within a livestock population and its development over time. If pedigree information is not available, linkage disequilibrium (LD) analysis might offer an alternative perspective for the estimation of effective population size. In this study, 128 individuals of the Swiss Eringer breed were genotyped using the Illumina BovineSNP50 beadchip. We set bin size at 50 kb for LD analysis, assuming that LD for proximal single nucleotide polymorphism (SNP)-pairs reflects distant breeding history while LD from distal SNP-pairs would reflect near history. Recombination rates varied among different regions of the genome. The use of physical distances as an approximation of genetic distances (e.g. setting 1 Mb = 0.01 Morgan) led to an upward bias in LD-based estimates of effective population size for generations beyond 50, while estimates for recent history were unaffected. Correction for restricted sample size did not substantially affect these results. LD-based actual effective population size was estimated in the range of 87-149, whereas pedigree-based effective population size resulted in 321 individuals. For conservation purposes, requiring knowledge of recent history (<50 generations), approximation assuming constant recombination rate seemed adequate.

AZGP1 is a tumor suppressor in pancreatic cancer inducing mesenchymal-to-epithelial transdifferentiation by inhibiting TGF-ß-mediated ERK signaling.

Epithelial-to-mesenchymal transdifferentiation (EMT) mediated by transforming growth factor-ß (TGF-ß) signaling leads to aggressive cancer progression. In this study, we identified zinc-α2-glycoprotein (AZGP1, ZAG) as a tumor suppressor in pancreatic ductal adenocarcinoma whose expression is lost due to histone deacetylation. In vitro, ZAG silencing strikingly increased invasiveness of pancreatic cancer cells accompanied by the induction of a mesenchymal phenotype. Expression analysis of a set of EMT markers showed an increase in the expression of mesenchymal markers (vimentin (VIM) and integrin-α5) and a concomitant reduction in the expression of epithelial markers (cadherin 1 (CDH1), desmoplakin and keratin-19). Blockade of endogenous TGF-ß signaling inhibited these morphological changes and the downregulation of CDH1, as elicited by ZAG silencing. In a ZAG-negative cell line, human recombinant ZAG (rZAG) specifically inhibited exogenous TGF-ß-mediated tumor cell invasion and VIM expression. Furthermore, rZAG blocked TGF-ß-mediated ERK2 phosphorylation. PCR array analysis revealed that ZAG-induced epithelial transdifferentiation was accompanied by a series of concerted cellular events including a shift in the energy metabolism and prosurvival signals. Thus, epigenetically regulated ZAG is a novel tumor suppressor essential for maintaining an epithelial phenotype.

A shared 336 kb haplotype associated with the belt pattern in three divergent cattle breeds.

We recently mapped the belt mutation in Brown Swiss cattle to a 922 kb interval on BTA3. In this study, we analysed two additional cattle breeds with the belted phenotype: Galloway and Dutch Belted (Lakenvelder). By genotyping microsatellites in solid-coloured and belted Galloways, we confirmed that the belt mutation in Galloways is strongly associated with the same chromosomal locus as in Brown Swiss cattle. Subsequently, we analysed 36 SNPs in the belt interval in three breeds. We identified a single belt-associated haplotype for each of the analysed breeds. The three breed-specific belt haplotypes share alleles in four blocks. Three of these blocks comprise only one single or two consecutive markers, while the largest shared haplotype block encompasses nine consecutive SNPs in a 336 kb interval. The large shared haplotype across divergent breeds suggests a common mutation for the belt phenotype in all three breeds. We identified a potential candidate gene within this interval coding for the developmental transcription factor HES6. We re-sequenced the complete HES6 coding sequence in belted and solid-coloured cattle but did not find belt-associated polymorphisms. In conclusion, our data provide strong evidence in favour of a common founder for the belt phenotype in different cattle breeds and have resulted in an improved fine-mapping of the causative mutation.

Seven novel KIT mutations in horses with white coat colour phenotypes.

White coat colour in horses is inherited as a monogenic autosomal dominant trait showing a variable expression of coat depigmentation. Mutations in the KIT gene have previously been shown to cause white coat colour phenotypes in pigs, mice and humans. We recently also demonstrated that four independent mutations in the equine KIT gene are responsible for the dominant white coat colour phenotype in various horse breeds. We have now analysed additional horse families segregating for white coat colour phenotypes and report seven new KIT mutations in independent Thoroughbred, Icelandic Horse, German Holstein, Quarter Horse and South German Draft Horse families. In four of the seven families, only one single white horse, presumably representing the founder for each of the four respective mutations, was available for genotyping. The newly reported mutations comprise two frameshift mutations (c.1126_1129delGAAC; c.2193delG), two missense mutations (c.856G>A; c.1789G>A) and three splice site mutations (c.338-1G>C; c.2222-1G>A; c.2684+1G>A). White phenotypes in horses show a remarkable allelic heterogeneity. In fact, a higher number of alleles are molecularly characterized at the equine KIT gene than for any other known gene in livestock species.

Genetic mapping of the belt pattern in Brown Swiss cattle to BTA3.

The white belt pattern of Brown Swiss cattle is characterized by a lack of melanocytes in a stretch of skin around the midsection. This pattern is of variable width and sometimes the belt does not fully circle the body. To identify the gene responsible for this colour variation, we performed linkage mapping of the belted locus using six segregating half-sib families including 104 informative meioses for the belted character. The pedigree confirmed a monogenic autosomal dominant inheritance of the belted phenotype in Brown Swiss cattle. We performed a genome scan using 186 microsatellite markers in a subset of 88 animals of the six families. Linkage with the belt phenotype was detected at the telomeric region of BTA3. Fine-mapping and haplotype analysis using 19 additional markers in this region refined the critical region of the belted locus to a 922-kb interval on BTA3. As the corresponding human and mouse chromosome segments contain no obvious candidate gene for this coat colour trait, the mutation causing the belt pattern in the Brown Swiss cattle might help to identify an unknown gene influencing skin pigmentation.