Bucci R, De Amicis I, Parrillo S, Robbe D, Carluccio A.Good sperm production is a notable requirement for subjects intended for reproduction, particularly in endangered species, and it has been demonstrated that in horse stallions, this is correlated to testicular volume. The present study, which involved Martina Franca jacks, aimed to determine whether, also in this endangered breed, there is a correlation between the total sperm number (TSN) and testicular volume. Testes were measured with both ultrasound and a caliper. Testicular volume was calculated using two different formulas: one representing the volume of an ellipsoid and one developed to...
Jia H, Gao S, Tang L, Fu Y, Xiong Y, Ente M, Mubalake S, Shao C, Li K, Hu D, Zhang D.The Przewalski's horse (Equus ferus przewalskii) is the only surviving wild horse species in the world. A significant population of Przewalski's horses resides in Xinjiang, China. Parasitosis poses a considerable threat to the conservation of this endangered species. Yet, there is limited information on the nematode parasites that infect these species. To deepen our understanding of parasitic fauna affecting wild horses, we identified the intestinal nematodes of Przewalski's horses in Xinjiang and added new barcode sequences to a public database. Methods: Between 2018 and 2021, nematodes were ...
Studying animal societies needs detailed observation of many individuals, but technological advances offer new opportunities in this field. Here, we present a state-of-the-art drone observation of a multilevel herd of Przewalski's horses, consisting of harems (one-male, multifemale groups). We track, in high spatio-temporal resolution, the movements of 238 individually identified horses on drone videos, and combine movement analyses with demographic data from two decades of population monitoring. Analysis of collective movements reveals how the structure of the herd's social network is related...
Salim AA, Butler MS, Blaskovich MAT, Henderson IR, Capon RJ.Covering literature to December 2022This review provides a comprehensive account of all natural products (500 compounds, including 17 semi-synthetic derivatives) described in the primary literature up to December 2022, reported to be capable of inhibiting the egg hatching, motility, larval development and/or the survival of helminths (, nematodes, flukes and tapeworms). These parasitic worms infect and compromise the health and welfare, productivity and lives of commercial livestock (, sheep, cattle, horses, pigs, poultry and fish), companion animals (, dogs and cats) and other high value, end...
Meuffels-Barkas J, Wilsher S, Allen WRT, Ververs C, Lueders I.Recent loss of rhinoceros subspecies has renewed interest in using more advanced assisted reproductive technologies (ART) in rhinoceroses and elephants. Currently, only semen collection, semen preservation and artificial insemination (AI) have been used repeatedly with success in these species. Although ovum pick-up (OPU) and intra-cytoplasmic sperm injection (ICSI) have been reported in rhinoceroses, the techniques are not yet optimised. In contrast, multiple ART applications are routinely used in the horse. Since elephant and rhinoceroses share some reproductive features with equids, we post...
Musiau0142 AD, Ropka-Molik K, Stefaniuk-Szmukier M, Myu0107ka G, Bieniek A, Yasynetska N.Przewalski horses are considered the last living population of wild horses, however, they are secondarily feral offspring of herds domesticated ~ 5000 years ago by the Botai culture. After Przewalski horses were almost extinct at the beginning of the twentieth century, their population is about 2500 individuals worldwide, with one of the largest breeding centers in Askania-Nova Biosphere Reserve (Ukraine). The research aimed to establish the maternal variation of Przewalski horses population maintained in Askania-Nova Reserve based on mitochondrial DNA hypervariable 1 and hypervariable 2 r...
Todd ET, Fromentier A, Sutcliffe R, Running Horse Collin Y, Perdereau A, Aury JM, u00c8che C, Bouchez O, Donnadieu C, Wincker P, Kalbfleisch T....Historical genomes can provide important insights into recent genomic changes in horses, especially the development of modern breeds. In this study, we characterized 8.7 million genomic variants from a panel of 430 horses from 73 breeds, including newly sequenced genomes from 20 Clydesdales and 10 Shire horses. We used this modern genomic variation to impute the genomes of four historically important horses, consisting of publicly available genomes from 2 Przewalski's horses, 1 Thoroughbred, and a newly sequenced Clydesdale. Using these historical genomes, we identified modern horses with high...
Masuda M, Nikadori A, Nikadori E, Uchida N, Takizawa Y, Ishimaru M, Yamamoto T, Yuasa R, Kugai H, Nagahama Y, Takasu M, Tozaki T.The Miyako horse is a native Japanese horse breed. As with other native Japanese horses, the number of Miyako horses decreased due to mechanization and motorization, which reduced their roles, with just 14 in 1980. Although their population had increased to 55 horses by 2021, a further increase in their numbers is required to avoid extinction. Recently, their breeding has involved natural mating during group grazing; therefore, pedigree management has been difficult, and individual identification has been inconclusive. With the aim of formulating an effective breeding plan, this study used mic...
In mammals, centromeres are epigenetically specified by the histone H3 variant CENP-A and are typically associated with satellite DNA. We previously described the first example of a natural satellite-free centromere on chromosome 11 (ECA11) and, subsequently, on several chromosomes in other species of the genus . We discovered that these satellite-free neocentromeres arose recently during evolution through centromere repositioning and/or chromosomal fusion, after inactivation of the ancestral centromere, where, in many cases, blocks of satellite sequences were maintained. Here, we investigate...
Rajabi-Toustani R, Tsogtgerel M, Gao Y, Li C, Sakato M, Haneda S, Cheong SH, Nambo Y.Japanese native horses, which consists of 8 breeds, are threatened with extinction. Embryo transfer (ET) is used to reproduce endangered animals in various mammalian species. We aimed to perform ET using native ponies from Kiso and Hokkaido as donors and recipients, respectively. ET operation included long-distance transport of non-cryopreserved embryos from Nagano Prefecture to Hokkaido. Embryos were transported 1500 km over 9 h in a container maintained at 22°C. After transferring two embryos to two recipients, one mare delivered a healthy live foal. These results demonstrated that reciproc...
Tang L, Yan L, Jia H, Xiong Y, Ma X, Chu H, Sun Z, Wang L, Shalitanati M, Li K, Hu D, Zhang D.Host-associated microbiota can significantly impact host fitness. Therefore, naturally occurring variations in microbiota may influence the health and persistence of their hosts. This finding is particularly important in reintroduced animals, as they typically experience habitat changes during translocations. However, little is known about how microbiomes are altered in response to conservation translocation. Here, we accessed the gut microbiome of Przewalski's horse (Equus przewalskii) populations in China from three nature reserves (i.e. Xinjiang Kalamaili Nature Reserve, KNR; Dunhuang Xihu ...
Suvu00e1 M, Arnold VH, Wiedenmann EA, Jordan R, Galvagno E, Martu00ednez M, Vichera GD.Somatic cell nuclear transfer (SCNT) is an asexual reproductive technique where cloned offspring contain the same genetic material as the original donor. Although this technique preserves the sex of the original animal, the birth of sex-reversed offspring has been reported in some species. Here, we report for the first time the birth of a female foal generated by SCNT of a male nuclear donor. After a single SCNT procedure, 16 blastocysts were obtained and transferred to eight recipient mares, resulting in the birth of two clones: one male and one female. Both animals had identical genetic prof...
Schubert CL, Ryckewaert B, Pereira C, Matsuzawa T.This study aimed to use a computer-controlled touchscreen system to examine visual discrimination in Garrano horses (), an endangered breed of pony belonging to the Iberian horse family. This pilot study focused on the perceptual similarity among letters of the alphabet. We tested five horses in a one-male unit (OMU) living permanently in a semi-free enclosure near their natural habitat in Serra d'Arga, northern Portugal. Horses were trained to nose-touch black circles that appeared on the screen. Then, they were tested for discrimination of five letters of the Latin alphabet in Arial font, na...
Flores Bragulat AP, Ortiz I, Catalu00e1n J, Dorado J, Hidalgo M, Losinno L, Dordas-Perpinyu00e0 M, Yu00e1nez-Ortiz I, Martu00ednez-Rodero I....Equus members exhibit very divergent karyotype, genetic plasticity, and significant differences in their reproductive physiology. Despite the fact that somatic cell nuclear transfer and intracytoplasmic sperm injection (ICSI) has gained relevance in the last few years in horses, few reports have been published exploring ovum pick up (OPU) and in vitro maturation (IVM) of cumulus-oocyte complexes (COCs) in donkeys. Yet, some donkey species and breeds are considered endangered, and these assisted-reproductive technologies could help to preserve the genetic of valuable individuals. In this study...
Hu D, Wang C, Ente M, Zhang K, Zhang D, Li X, Li K, Chu H.Intestinal microbiota play an important role in the survival of the host. However, no study to date has elucidated the adjustment of intestinal microbiota of the host during rewilding. Thus, this study aims to describe the intestinal bacterial community of reintroduced Przewalski’s horse (RPH) after being released into their original habitat for approximately 20 years in comparison with that of captive Przewalski’s horse (CPH), sympatric domestic horse (DH) and Mongolian wild ass (MWA) by sequencing the 16S rRNA gene. The results showed that the prevalent bacterial communities were differe...
D'Anza E, Buono F, Albarella S, Castaldo E, Pugliano M, Iannuzzi A, Cascone I, Battista E, Peretti V, Ciotola F.The Pony of Esperia is an Italian autochthonous horse breed reared in the wild on the Aurunci and Ausoni Mountains. Currently, it is considered an endangered breed, as its population consists of 1623 animals. It is therefore essential to identify all aspects that can improve the management and economy of its breeding, favoring its diffusion. In this paper, the effects of intestinal strongyle infection on the chromosome stability of peripheral blood lymphocytes (PBLs) was evaluated through aneuploidy and chromosome aberration (gap, chromatid and chromosome breaks, and the number of abnormal cel...
Leonardi M, Boschin F, Boscato P, Manica A.Predicting the effects of future global changes on species requires a better understanding of the ecological niche dynamics in response to climate; the large climatic fluctuations of the last 50,000 years can be used as a natural experiment to that aim. Here we test whether the realized niche of horse, aurochs, red deer, and wild boar changed between 47,000 and 7500 years ago using paleoecological modelling over an extensive archaeological database. We show that they all changed their niche, with species-specific responses to climate fluctuations. We also suggest that they survived the climati...
Zhang K, Zhou R, Huang H, Ma W, Qi Y, Li B, Zhang D, Li K, Chu H.The aim of this study was to identify the aggregation sites and transmission characteristics of Gasterophilus pecorum, the dominant pathogen of endangered equines in desert steppe. Therefore, we tested with a four-arm olfactometer the olfactory response of the G. pecorum adults to the odors that have a great impact on their life cycle, and also investigated the occurrence sites of the adults in the area where the Przewalski's horse (Equus przewalskii) roam frequently during the peak period of G. pecorum infection. The results of four-directional olfactory test showed that the fresh horse feces...
de Jonge N, Carlsen B, Christensen MH, Pertoldi C, Nielsen JL.The gut microbiome plays a critical role in many aspects of host life, and the microbial community composition is heavily influenced by the prevailing conditions in the gut environment. Community composition has been suggested to have large implications for conservation efforts, and gut health has become of interest for optimizing animal care in captivity. In this study, we explore the gut microbiome of a wide range of animals in the context of conservation biology. The composition of the gut microbial community of 54 mammalian animal species was investigated using 16S rRNA gene amplicon seque...
Bernu00e1tkovu00e1 A, Oyunsaikhan G, u0160imek J, Komu00e1rkovu00e1 M, Bobek M, Ceacero F.Reintroduction is a common technique for re-establishing threatened species. However, the adaptation to novel habitats with distinct conditions poses a risk of failure. Weather conditions affect the behaviour of animals, and thus, their adaptation to new conditions and survival. Reintroduced Przewalski's horses living in Mongolia's continental arid climate with extreme temperature and precipitation variability, serve as an ideal model species for studying the behavioural response of selected groups to these harsh conditions. Methods: The research was conducted in The Great Gobi B Strictly Prot...
Tang L, Gao Y, Yan L, Jia H, Chu H, Ma X, He L, Wang X, Li K, Hu D, Zhang D.The gut microbiome offers important ecological benefits to the host; however, our understanding of the functional microbiome in relation to wildlife adaptation, especially for translocated endangered species, is lagging. In this study, we adopted a comparative metagenomics approach to test whether the microbiome diverges for translocated and resident species with different adaptive potentials. The composition and function of the microbiome of sympatric Przewalski's horses and Asiatic wild asses in desert steppe were compared for the first time using the metagenomic shotgun sequencing approach....
Tang Y, Liu G, Zhao S, Li K, Zhang D, Liu S, Hu D.Major histocompatibility complex (MHC) genes are the most polymorphic in vertebrates and the high variability in many MHC genes is thought to play a crucial role in pathogen recognition. The MHC class II locus DQA polymorphism was analyzed in the endangered Przewalski's horse, , a species that has been extinct in the wild and all the current living individuals descend from 12 founders. We used the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) to detect the polymorphism within the MHC DQA in 31 Przewalski's horses from two reintroduced populations. Consequently, o...
Cai D, Zhu S, Gong M, Zhang N, Wen J, Liang Q, Sun W, Shao X, Guo Y, Cai Y, Zheng Z, Zhang W, Hu S, Wang X, Tian H, Li Y, Liu W, Yang M, Yang J, Wu D....The exceptionally rich fossil record available for the equid family has provided textbook examples of macroevolutionary changes. Horses, asses, and zebras represent three extant subgenera of lineage, while the subgenus is another remarkable lineage ranging from North America to Ethiopia in the Pleistocene. We sequenced 26 archaeological specimens from Northern China in the Holocene that could be assigned morphologically and genetically to , a species representative of . We present the first high-quality complete genome of the lineage, which was sequenced to 13.4× depth of coverage. Radioc...
Milnes EL, Skelding AM, Larouche CB, Ferro A, Delnatte P, Dutton C, Anderson NE.To compare ketamine-butorphanol-azaperone-medetomidine (KBAM) to detomidine-etorphine-acepromazine (DEA) for field anesthesia in captive Przewalski horses (Equus przewalskii). Methods: 10 adult Przewalski horses. Methods: A prospective randomized crossover trial was conducted. Each horse was immobilized once with KBAM (200 mg ketamine, 109.2 mg butorphanol, 36.4 mg azaperone, and 43.6 mg medetomidine) and once with DEA (40 mg detomidine premedication, followed 20 minutes later by 3.9 to 4.4 mg etorphine and 16 to 18 mg acepromazine). Both protocols were administered by IM remote dart injection...
Larison B, Pinho GM, Haghani A, Zoller JA, Li CZ, Finno CJ, Farrell C, Kaelin CB, Barsh GS, Wooding B, Robeck TR, Maddox D, Pellegrini M, Horvath S.Effective conservation and management of threatened wildlife populations require an accurate assessment of age structure to estimate demographic trends and population viability. Epigenetic aging models are promising developments because they estimate individual age with high accuracy, accurately predict age in related species, and do not require invasive sampling or intensive long-term studies. Using blood and biopsy samples from known age plains zebras (Equus quagga), we model epigenetic aging using two approaches: the epigenetic clock (EC) and the epigenetic pacemaker (EPM). The plains zebra...
Murchie TJ, Monteath AJ, Mahony ME, Long GS, Cocker S, Sadoway T, Karpinski E, Zazula G, MacPhee RDE, Froese D, Poinar HN.The temporal and spatial coarseness of megafaunal fossil records complicates attempts to to disentangle the relative impacts of climate change, ecosystem restructuring, and human activities associated with the Late Quaternary extinctions. Advances in the extraction and identification of ancient DNA that was shed into the environment and preserved for millennia in sediment now provides a way to augment discontinuous palaeontological assemblages. Here, we present a 30,000-year sedimentary ancient DNA (sedaDNA) record derived from loessal permafrost silts in the Klondike region of Yukon, Canada. ...
Boyce P, Bhattacharyya J, Linklater W.Conservation issues are often complicated by sociopolitical controversies that reflect competing philosophies and values regarding natural systems, animals, and people. Effective conservation outcomes require managers to engage myriad influences (social, cultural, political, and economic, as well as ecological). The contribution of conservation scientists who generate the information on which solutions rely is constrained if they are unable to acknowledge how personal values and disciplinary paradigms influence their research and conclusions. Conservation challenges involving controversial spe...
Dell A, Curry M, Hunter E, Dalton R, Yarnell K, Starbuck G, Wilson PB.The consequences of poor breed management and inbreeding can range from gradual declines in individual productivity to more serious fertility and mortality concerns. However, many small and closed groups, as well as larger unmanaged populations, are plagued by genetic regression, often due to a dearth in breeding support tools which are accessible and easy to use in supporting decision-making. To address this, we have developed a population management tool (BCAS, Breed Conservation and Management System) based on individual relatedness assessed using pedigree-based kinship, which offers breedi...
Huang H, Zhang K, Zhang B, Liu S, Chu H, Qi Y, Zhang D, Li K.Gasterophilus spp. have been found to be widespread in reintroduced Przewalski's horses in the Kalamaili Nature Reserve (Northwest China). However, data on the annual variation in Gasterophilus infections are lacking. To analyze the epidemiological features and determine the cause of the annual variation in Gasterophilus infections, we treated 110 Przewalski's horses with ivermectin and collected Gasterophilus larvae from fecal samples each winter from 2007 to 2019. All 110 Przewalski's horses studied were found to be infected by Gasterophilus spp., and a total of 141 379 larvae were collected...
Nagy K, Sung HK, Zhang P, Laflamme S, Vincent P, Agha-Mohammadi S, Woltjen K, Monetti C, Michael IP, Smith LC, Nagy A.The domesticated horse represents substantial value for the related sports and recreational fields, and holds enormous potential as a model for a range of medical conditions commonly found in humans. Most notable of these are injuries to muscles, tendons, ligaments and joints. Induced pluripotent stem (iPS) cells have sparked tremendous hopes for future regenerative therapies of conditions that today are not possible to cure. Equine iPS (EiPS) cells, in addition to bringing promises to the veterinary field, open up the opportunity to utilize horses for the validation of stem cell based therapi...
Przewalski's horses (PHs, Equus ferus ssp. przewalskii) were discovered in the Asian steppes in the 1870s and represent the last remaining true wild horses. PHs became extinct in the wild in the 1960s but survived in captivity, thanks to major conservation efforts. The current population is still endangered, with just 2,109 individuals, one-quarter of which are in Chinese and Mongolian reintroduction reserves [1]. These horses descend from a founding population of 12 wild-caught PHs and possibly up to four domesticated individuals [2-4]. With a stocky build, an erect mane, and stripped and sho...
Metcalf JL, Song SJ, Morton JT, Weiss S, Seguin-Orlando A, Joly F, Feh C, Taberlet P, Coissac E, Amir A, Willerslev E, Knight R, McKenzie V, Orlando L.The mammal gut microbiome, which includes host microbes and their respective genes, is now recognized as an essential second genome that provides critical functions to the host. In humans, studies have revealed that lifestyle strongly influences the composition and diversity of the gastrointestinal microbiome. We hypothesized that these trends in humans may be paralleled in mammals subjected to anthropogenic forces such as domestication and captivity, in which diets and natural life histories are often greatly modified. We investigated fecal microbiomes of Przewalski's horse (PH; Equus ferus p...
Haile J, Froese DG, Macphee RD, Roberts RG, Arnold LJ, Reyes AV, Rasmussen M, Nielsen R, Brook BW, Robinson S, Demuro M, Gilbert MT, Munch K....Causes of late Quaternary extinctions of large mammals ("megafauna") continue to be debated, especially for continental losses, because spatial and temporal patterns of extinction are poorly known. Accurate latest appearance dates (LADs) for such taxa are critical for interpreting the process of extinction. The extinction of woolly mammoth and horse in northwestern North America is currently placed at 15,000-13,000 calendar years before present (yr BP), based on LADs from dating surveys of macrofossils (bones and teeth). Advantages of using macrofossils to estimate when a species became extinc...
Librado P, Der Sarkissian C, Ermini L, Schubert M, Ju00f3nsson H, Albrechtsen A, Fumagalli M, Yang MA, Gamba C, Seguin-Orlando A, Mortensen CD....Yakutia, Sakha Republic, in the Siberian Far East, represents one of the coldest places on Earth, with winter record temperatures dropping below -70 °C. Nevertheless, Yakutian horses survive all year round in the open air due to striking phenotypic adaptations, including compact body conformations, extremely hairy winter coats, and acute seasonal differences in metabolic activities. The evolutionary origins of Yakutian horses and the genetic basis of their adaptations remain, however, contentious. Here, we present the complete genomes of nine present-day Yakutian horses and two ancient specim...
Vilstrup JT, Seguin-Orlando A, Stiller M, Ginolhac A, Raghavan M, Nielsen SC, Weinstock J, Froese D, Vasiliev SK, Ovodov ND, Clary J, Helgen KM....The genus Equus is richly represented in the fossil record, yet our understanding of taxonomic relationships within this genus remains limited. To estimate the phylogenetic relationships among modern horses, zebras, asses and donkeys, we generated the first data set including complete mitochondrial sequences from all seven extant lineages within the genus Equus. Bayesian and Maximum Likelihood phylogenetic inference confirms that zebras are monophyletic within the genus, and the Plains and Grevy's zebras form a well-supported monophyletic group. Using ancient DNA techniques, we further charact...
Lippold S, Knapp M, Kuznetsova T, Leonard JA, Benecke N, Ludwig A, Rasmussen M, Cooper A, Weinstock J, Willerslev E, Shapiro B, Hofreiter M.Modern domestic horses display abundant genetic diversity within female-inherited mitochondrial DNA, but practically no sequence diversity on the male-inherited Y chromosome. Several hypotheses have been proposed to explain this discrepancy, but can only be tested through knowledge of the diversity in both the ancestral (pre-domestication) maternal and paternal lineages. As wild horses are practically extinct, ancient DNA studies offer the only means to assess this ancestral diversity. Here we show considerable ancestral diversity in ancient male horses by sequencing 4 kb of Y chromosomal DNA ...
Todd ET, Ho SYW, Thomson PC, Ang RA, Velie BD, Hamilton NA.The Thoroughbred horse has played an important role in both sporting and economic aspects of society since the establishment of the breed in the 1700s. The extensive pedigree and phenotypic information available for the Thoroughbred horse population provides a unique opportunity to examine the effects of 300 years of selective breeding on genetic load. By analysing the relationship between inbreeding and racing performance of 135,572 individuals, we found that selective breeding has not efficiently alleviated the Australian Thoroughbred population of its genetic load. However, we found evidenc...
Arnold W, Ruf T, Kuntz R.Many large mammals show pronounced seasonal fluctuations of metabolic rate (MR). It has been argued, based on studies in ruminants, that this variation merely results from different levels of locomotor activity (LA), and heat increment of feeding (HI). However, a recent study in red deer (Cervus elaphus) identified a previously unknown mechanism in ungulates--nocturnal hypometabolism--that contributed significantly to reduced energy expenditure, mainly during late winter. The relative contribution of these different mechanisms to seasonal adjustments of MR is still unknown, however. Therefore,...
Lau AN, Peng L, Goto H, Chemnick L, Ryder OA, Makova KD.Despite their ability to interbreed and produce fertile offspring, there is continued disagreement about the genetic relationship of the domestic horse (Equus caballus) to its endangered wild relative, Przewalski's horse (Equus przewalskii). Analyses have differed as to whether or not Przewalski's horse is placed phylogenetically as a separate sister group to domestic horses. Because Przewalski's horse and domestic horse are so closely related, genetic data can also be used to infer domestication-specific differences between the two. To investigate the genetic relationship of Przewalski's hors...
Goto H, Ryder OA, Fisher AR, Schultz B, Kosakovsky Pond SL, Nekrutenko A, Makova KD.The endangered Przewalski's horse is the closest relative of the domestic horse and is the only true wild horse species surviving today. The question of whether Przewalski's horse is the direct progenitor of domestic horse has been hotly debated. Studies of DNA diversity within Przewalski's horses have been sparse but are urgently needed to ensure their successful reintroduction to the wild. In an attempt to resolve the controversy surrounding the phylogenetic position and genetic diversity of Przewalski's horses, we used massively parallel sequencing technology to decipher the complete mitoch...
Salamone DF, Canel NG, Rodru00edguez MB.Intracytoplasmic sperm injection (ICSI) has become a useful technique for clinical applications in the horse-breeding industry. However, both ICSI blastocyst and offspring production continues to be limited for most farm and wild species. This article reviews technical differences of ICSI performance among species, possible biological and methodological reasons for the variable efficiency and potential strategies to improve the outcomes. One of the major applications of ICSI in animal production is the reproduction of high-value specimens. Unfortunately, some domestic species like the bovine s...
Hedrick PW, Parker KM, Miller EL, Miller PS.The major histocompatibility complex (MHC) is a fundamental part of the vertebrate immune system, and the high variability in many MHC genes is thought to play an essential role in recognition of parasites. The Przewalski's horse is extinct in the wild and all the living individuals descend from 13 founders, most of whom were captured around the turn of the century. One of the primary genetic concerns in endangered species is whether they have ample adaptive variation to respond to novel selective factors. In examining 14 Przewalski's horses that are broadly representative of the living animal...
Takasu M, Hiramatsu N, Tozaki T, Kakoi H, Nakagawa T, Hasegawa T, Huricha , Maeda M, Murase T, Mukoyama H.In order to contribute to conservation of the endangered Kiso horse, we clarified their genetic information using 31 microsatellite DNAs, and genotyped 125 horses, 83% of the existing breed. First, we clarified the current status of the horses. The horses were confirmed to have experienced rapid loss of population causing a bottleneck, and their effective population size was much smaller than their census size. Moreover, the number of alleles (6.3), observed heterozygosity (0.674), and expected heterozygosity (0.662) were in the same range as other endangered horses all over the world. Therefo...
Li Y, Zhang K, Liu Y, Li K, Hu D, Wronski T.Large and complex intestinal microbiota communities in hosts have profound effects on digestion and metabolism. To better understand the community structure of intestinal microbiota in Przewalski's horse () under different feeding regimes, we compared bacterial diversity and composition between captive and reintroduced Przewalski's horses, using high-throughput 16S-rRNA gene sequencing for identification. Reintroduced Przewalski's horses were sampled in two Chinese nature reserves, i.e., Dunhuang Xihu Nature Reserve (DXNR; = 8) in Gansu Province and Kalamaili Nature Reserve (KNR; = 12) in Xi...
Luu00eds C, Juras R, Oom MM, Cothran EG.There are three native Portuguese horse breeds: Lusitano, Sorraia and Garrano. This study compares diversity patterns of 17 protein and 12 microsatellite markers in these three as well as 30 other breeds to infer relationships among the breeds and to compare levels of polymorphism of these breeds for use in conservation efforts. The Garrano and the Lusitano showed a high level of genetic diversity, similar to that observed for most of the other analysed breeds, while the Sorraia and Friesian breeds showed low levels of variation for both genetic marker types. The combined protein and microsate...
Ablondi M, Dadousis C, Vasini M, Eriksson S, Mikko S, Sabbioni A.Horses are nowadays mainly used for sport and leisure activities, and several local breeds, traditionally used in agriculture, have been exposed to a dramatic loss in population size and genetic diversity. The loss of genetic diversity negatively impacts individual fitness and reduces the potential long-term survivability of a breed. Recent advances in molecular biology and bioinformatics have allowed researchers to explore biodiversity one step further. This study aimed to evaluate the loss of genetic variability and identify genomic regions under selection pressure in the Bardigiano breed ba...
Ginolhac A, Vilstrup J, Stenderup J, Rasmussen M, Stiller M, Shapiro B, Zazula G, Froese D, Steinmann KE, Thompson JF, Al-Rasheid KA, Gilbert TM....Second-generation sequencing technologies have revolutionized our ability to recover genetic information from the past, allowing the characterization of the first complete genomes from past individuals and extinct species. Recently, third generation Helicos sequencing platforms, which perform true Single-Molecule DNA Sequencing (tSMS), have shown great potential for sequencing DNA molecules from Pleistocene fossils. Here, we aim at improving even further the performance of tSMS for ancient DNA by testing two novel tSMS template preparation methods for Pleistocene bone fossils, namely oligonucl...
Liu SH, Li K, Hu DF.A survey was conducted on the detection of the larval Gasterophilus species in 90 equines via necropsy or after administering oral ivermectin in Xinjian, China, from 2008 to 2013. All 90 (100%) equines were infested by larval Gasterophilus, and 3723second instar larvae (L2) and 63,778 third instar larvae (L3) were collected from faecal samples and the digestive tract, a ratio of L2:L3=1:17. Over 84.45% of the animals contained ≤1500 larvae and 7.78% had >2000 larvae. The highest totals of L2 and L 3 larvae in any one animal were 1208 in Mongolian wild ass (Equus hemionus hemionus), 2491 i...
Oakenfull EA, Ryder OA.Variation in the control region and the 12S rRNA gene of all surviving mitochondrial lineages of Przewalski's horse was investigated. Variation is low despite the present day population being descended from 13 individuals probably representing animals from three different regions of its range. Phylogenetic comparison of these sequences, with sequences for the domestic horse, does not resolve the ancestral status of either horse.
Wohlsein P, Lehmbecker A, Spitzbarth I, Algermissen D, Baumgu00e4rtner W, Bu00f6er M, Kummrow M, Haas L, Grummer B.In a zoological collection, four black bears (Ursus americanus) died from neurological disease within six months. Independently in a geographically different zoo, two Thomson's gazelles (Eudorcas thomsoni) and 18 guinea pigs (Cavia porcellus f. dom.) suffered from neurological disorders. In addition, guinea pigs showed abortions and stillbirths. All affected animals displayed a non suppurative meningoencephalitis with intranuclear inclusion bodies. Immunohistology demonstrated equine herpes virus antigen and ultrastructurally herpes viral particles were detected. Virus isolation and molecular ...
Huang H, Zhang B, Chu H, Zhang D, Li K.We investigated infections with Gasterophilus spp. in three equids within the Kalamaili Nature Reserve (northern China). We conducted necropsies on 6 Przewalski's horses (Equus ferus przewalskii) and 6 Mongolian wild asses (Equus hemionus) and administered ivermectin to 10 overwintering domestic horses to expel parasites during winter periods. All 22 equids studied (100%) were infested with Gasterophilus spp. and a total of 17,225 larvae were collected. These included six species: G. haemorrhoidalis, G. inermis, G. intestinalis, G. nasalis, G. nigricornis, and G. pecorum. The mean intensity of...
Kaczensky P, Ganbataar O, Altansukh N, Enkhsaikhan N, Stauffer C, Walzer C.Large mammals re-introduced into harsh and unpredictable environments are vulnerable to stochastic effects, particularly in times of global climate change. The Mongolian Gobi is home to several rare large ungulates such as re-introduced Przewalski's horses (Equus ferus przewalskii) and Asiatic wild asses (Equus hemionus), but also to a millennium-old semi-nomadic livestock herding culture.The Gobi is prone to large inter-annual environmental fluctuations, but the winter 2009/2010 was particularly severe. Millions of livestock died and the Przewalski's horse population in the Gobi crashed. We u...
Souris AC, Kaczensky P, Julliard R, Walzer C.The Przewalski's horse (Equus ferus przewalskii) became extinct in the wild in the 1960s, but survived as a species due to captive breeding. There have been several initiatives to re-introduce the species in central Asia, but until now only two projects in Mongolia establish free-ranging populations. Data on basic ecology and behavior of the species prior to extinction is largely lacking and a good documentation of the re-introduction process is essential. Between 13 May and 2 September 2003 we documented the time budget-, group synchrony and body score development of a newly released Przewals...
Solow AR, Roberts DL, Robbirt KM.The fossil record has been used to shed light on the late Pleistocene megafaunal extinctions in North America and elsewhere. It is therefore important to account for variability due to the incompleteness of the fossil record and error in dating fossil remains. Here, a joint confidence region for the extinction times of horses and mammoths in Alaska is constructed. The results suggest that a prior claim that the extinction of horses preceded the arrival of humans cannot be made with confidence.
Maigrot AL, Hillmann E, Anne C, Briefer EF.Vocal expression of emotions has been suggested to be conserved throughout evolution. However, since vocal indicators of emotions have never been compared between closely related species using similar methods, it remains unclear whether this is the case. Here, we investigated vocal indicators of emotional valence (negative versus positive) in Przewalski's horses, in order to find out if expression of valence is similar between species and notably among Equidae through a comparison with previous results obtained in domestic horse whinnies. We observed Przewalski's horses in naturally occurring ...
Higuchi RG, Wrischnik LA, Oakes E, George M, Tong B, Wilson AC.Sequences are reported for portions of two mitochondrial genes from a domestic horse and a plains zebra and compared to those published for a quagga and a mountain zebra. The extinct quagga and plains zebra sequences are identical at all silent sites, whereas the horse sequence differs from both of them by 11 silent substitutions. Postmortem changes in quagga DNA may account for the two coding substitutions between the quagga and plains zebra sequences. The hypothesis that the closest relative of the quagga is the domestic horse receives no support from these data. From the extent of sequence ...
Zhang Y, Cao QS, Rubenstein DI, Zang S, Songer M, Leimgruber P, Chu H, Cao J, Li K, Hu D.Acquiring water is essential for all animals, but doing so is most challenging for desert-living animals. Recently Przewalski's horse has been reintroduced to the desert area in China where the last wild surviving member of the species was seen before it vanished from China in the 1960s. Its reintroduction placed it within the range of a close evolutionary relative, the con-generic Khulan. Determining whether or not these two species experience competition and whether or not such competition was responsible for the extinction of Przewalski's horses in the wild over 50 years ago, requires ident...
Aranguren-Mu00e9ndez J, Jordana J, Gomez M.Genetic diversity at 13 equine microsatellite loci was compared in five endangered Spanish donkey breeds: Andaluza, Catalana, Mallorquina, Encartaciones and Zamorano-Leonesa. All of the equine microsatellites used in this study were amplified and were polymorphic in the domestic donkey breeds with the exception of HMS1, which was monomorphic, and ASB2, which failed to amplify. Allele number, frequency distributions and mean heterozygosities were very similar among the Spanish donkey breeds. The unbiased expected heterozygosity (H(E)) over all the populations varied between 0.637 and 0.684 in t...
Science (New York, N.Y.)April 16, 1965
Volume 148, Issue 3668 382-383 doi: 10.1126/science.148.3668.382
BENIRSCHKE K, MALOUF N, LOW RJ, HECK H.The chromosome number of the domestic horse is 2n = 64; different races have the same complement. The chromosomes of two Przewalski's horses (at Catskill Game Farm, New York), presumably ancestral wild horses from Mongolia, are identical: 2n = 66, with more acrocentric and fewer metacentric elements than the chromosomes of the domestic horse. This apparent difference in karyotype may help resolve the questions of "purity" in the relatively few remaining Przewalski's horses. Moreover, these findings are of interest in relation to the apparent fertility of hybrids between these species.
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