Przewalski's Horse Research Articles

Microsatellite markers for evaluating the diversity of the natural killer complex and major histocompatibility complex genomic regions in domestic horses.

Genotyping microsatellite markers represents a standard, relatively easy, and inexpensive method of assessing genetic diversity of complex genomic regions in various animal species, such as the major histocompatibility complex (MHC) and/or natural killer cell receptor (NKR) genes. MHC-linked microsatellite markers have been identified and some of them were used for characterizing MHC polymorphism in various species, including horses. However, most of those were MHC class II markers, while MHC class I and III sub-regions were less well covered. No tools for studying genetic diversity of NKR complex genomic regions are available in horses. Therefore, the aims of this work were to establish a panel of markers suitable for analyzing genetic diversity of the natural killer complex (NKC), and to develop additional microsatellite markers of the MHC class I and class III genomic sub-regions in horses. Nine polymorphic microsatellite loci were newly identified in the equine NKC. Along with two previously reported microsatellites flanking this region, they constituted a panel of 11 loci allowing to characterize genetic variation in this functionally important part of the horse genome. Four newly described MHC class I/III-linked markers were added to 11 known microsatellites to establish a panel of 15 MHC markers with a better coverage of the class I and class III sub-regions. Major characteristics of the two panels produced on a group of 65 horses of 13 breeds and on five Przewalski's horses showed that they do reflect genetic variation within the horse species.

Preliminary observations of the behaviour in two wild equids: Przewalski horse (Equus ferus przewalskii) and Hartmann’s zebra (Equus zebra hartmannae) kept in socially changed groups at Warsaw Zoo

Preliminary observations of the behaviour in two wild equids: Przewalski horse (Equus ferus przewalskii) and Hartmann’s zebra (Equus zebra hartmannae) kept in socially changed groups at Warsaw Zoo

Asian horses deepen the MSY phylogeny.

Humans have shaped the population history of the horse ever since domestication about 5500years 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 1.46Mb 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±872years. 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.

Mapping of Vegetation with the Geoinformation System and Determining of Carrying Capacity of the Pre-Urals Steppe area for a Newly Establishing Population of the Przewalski Horse Equus ferus przewalskii at the Orenburg State Nature Reserve

Mapping of the vegetation (1:25000) of the Pre-Urals Steppe area at the Orenburg State Nature Reserve was completed in 2016. A map created with the geoinformation system contains 1931 simple and complex polygons for 25 types of vegetation. In a drought year, the average stock of palatable vegetation of the whole area is estimated at 8380 tons dry weight. The estimation is based on the size of areas covered by different types of vegetation, their grass production, the correction coefficients for decreasing of pasture forage stocks in winter and decreasing of production of grass communities in dry years. Based on pasture forage stocks the area could tolerate the maximum population size of 1769 individuals of the Przewalski horse, their average density could be 0.11 horse per ha. Yet, as watering places for animals are limited in Pre-Urals Steppe, grazing pressures on the vegetation next to the water sources may increase in dry years. That is why the above-mentioned calculated maximum population size and density must be reduced at least by half until some additional watering places are established and monitoring of the grazing effect on the vegetation next to the places is carried out regularly. Thus, the maximum size of the population is estimated at 800 to 900 individuals, which is almost 1.5 times more than necessary to establish a self-sustained population of the Przewalski horse.

The use of abandoned buildings by Przewalski's horses in the Chornobyl Exclusion Zone, Ukraine

Abstract The aim of the study was to determine whether there are any factors that affect the utilization of abandoned farm buildings by Przewalski's horses in the Chornobyl Exclusion Zone, Ukraine. The buildings are the remains of former collective farms that were abandoned after the nuclear disaster. We examined 64 buildings of various sizes and location regarding feces cover within the buildings, substrate, geographical orientation, and selected measures of the building structure. A general linear model explained less than 70% of feces cover variability. The substrate type was the most influential variable: hard substrate (concrete or asphalt) presented statistically lower feces cover than medium and soft substrate. Building length was another important building feature that influences feces cover. Other features were not statistically significant. The usage of buildings may be related to the negative influence of hard substrate (concrete or asphalt) on horses' hooves, aggression between individuals in groups, and sense of security. Other factors that were not statistically significant could play an antagonistic role in horses' choices depending on the season; however, these could not be identified in this study.

Seasonal Variations in Heart Rate Variability as an Indicator of Stress in Free-Ranging Pregnant Przewalski's Horses (E. ferus przewalskii) within the Hortobágy National Park in Hungary.

Background: Ecosystems with seasonal fluctuations in climate and food availability present physiological challenges to resident mammals and may cause “stress.” The two predominant physiological responses to stressors are (1) the activation of the hypothalamic-pituitary-adrenal axis and (2) the modulation of the autonomic nervous system. To date, the primary indicator for “stress” in wildlife- and zoo animal research are glucocorticoid levels. By measuring the autonomic regulation of cardiac activity, particularly the vagal tone, heart rate variability (HRV) is presently emerging as a suitable indicator of “stress” in farm- and domestic animal research.Objective: The aim of this study was to use HRV, a novel method in wildlife research, to assess seasonal patterns of “stress” in a group of free-ranging Przewalski's horses (Equus ferus przewalskii).Methods: Six pregnant Przewalski's horses from one harem within the Hortobágy National Park in Hungary were subjected to the study. We used a dedicated telemetry system consisting of a subcutaneously implanted transmitter and a receiver and storage unit in a collar to record HRV, heart rate (HR), subcutaneous body temperature, and activity throughout a one-year study period—climate data was also collected. We defined “stress” as a decrease in parasympathetic nervous system tone and calculated RMSSD (root mean square of successive differences) as a measure of HRV. Linear mixed effects models with random intercept per individual were used for statistical analysis.Results: HRV and HR varied considerably throughout the year. Similar to temperate ruminants and hibernating mammals, Przewalski's horses experienced lower HR and HRV during winter, when resources are limited indicating decreased metabolic rates coupled with “stress.” In spring, we observed a drop of HRV along with a peak in HR indicating an increase of allostatic load that is most likely associated with increased energy demands during pregnancy and/or seasonal routines such as the adjustment of the gastrointestinal system to better quality diet.Conclusion: Measuring telemetric HRV is a proven method to study undisturbed reactions of wild animals to their changing environment over the long term. Przewalski's horses experience a loss of complexity in cardiovascular dynamics over the winter and particularly during spring, indicating seasonal “stress.”

Problems in the Protection of Reintroduced Przewalski's Horses (Equus ferus przewalskii) Caused by Piroplasmosis.

The objectives of our research on equine piroplasmosis were to clarify the prevalence of the piroplasms Babesia caballi and Theileria equi among reintroduced Przewalski's horses (takhi, Equus ferus przewalskii) in comparison with horses (Equus caballus) of nomads from around Hustai National Park in Mongolia and to determine the mortality among takhi during 2012 to 2015. The prevalence of T. equi was high in 2014 at 80% among nomadic horses and 84% among takhi. We found no evidence of B. caballi infection among takhi. A homology comparison of the 18S rRNA base sequence of T. equi showed the same sequence in both domestic horses and takhi. According to the national park records, piroplasmosis is a cause of high mortality in young takhi (19%). The results suggested that takhi were infected with T. equi in this park, and the infection is an important issue when reintroducing the takhi into the wild and increasing the numbers of the animals in nature. Continuous monitoring and vector control were noted as important issues in future conservation programs.

SURVEY OF ANAPLASMA PHAGOCYTOPHILUM ANTIBODIES IN CAPTIVE PRZEWALSKI'S HORSES (EQUUS FERUS PRZEWALSKII).

Anaplasma phagocytophilum (formerly Ehrlichia equi ) is a tickborne pathogen of domestic horses and the causative agent of equine granulocytic anaplasmosis. After the occurrence of clinical anaplasmosis in a Przewalski's horse ( Equus ferus przewalskii) housed at the Smithsonian Conservation Biology Institute in 2008, opportunistic serosurveillance of the herd was initiated. From 2008 to 2014, 57 serum samples were collected from 27 individuals (10 males; 17 females). Using indirect immunofluorescent antibody assays for anti- Anaplasma phagocytophilum antibodies, it was determined that prevalence was 53%. No significant sex differences were identified. A statistical association between increasing age and seropositive status suggests cumulative risk of exposure to Anaplasma phagocytophilum . After exclusion of four clinical cases of anaplasmosis, it was found that 22-57% of those sampled each year were seropositive and clinically normal, suggesting that the majority of Przewalski's horses develop subclinical or self-limiting anaplasmosis after exposure to A. phagocytophilum .

Genetic diversity of Syrian Arabian horses.

Although Arabian horses have been bred in strains for centuries and pedigrees have been recorded in studbooks, to date, little is known about the genetic diversity within and between these strains. In this study, we tested if the three main strains of Syrian Arabian horses descend from three founders as suggested by the studbook. We examined 48 horses representing Saglawi (n=18), Kahlawi (n=16) and Hamdani (n=14) strains using the Equine SNP70K BeadChip. For comparison, an additional 24 Arabian horses from the USA and three Przewalski's horses as an out group were added. Observed heterozygosis (Ho ) ranged between 0.30 and 0.32, expected heterozygosity (He ) between 0.30 and 0.31 and inbreeding coefficients (Fis ) between -0.02 and -0.05, indicating high genetic diversity within Syrian strains. Likewise, the genetic differentiation between the three Syrian strains was very low (Fst <0.05). Hierarchical clustering showed a clear distinction between Arabian and Przewalski's horses. Among Arabian horses, we found three clusters containing either horses from the USA or horses from Syria or horses from Syria and the USA together. Individuals from the same Syrian Arabian horse strain were spread across different sub-clusters. When analyzing Syrian Arabian horses alone, the best population differentiation was found with three distinct clusters. In contrast to expectations from the studbook, these clusters did not coincide with strain affiliation. Although this finding supports the hypothesis of three founders, the genetic information is not consistent with the currently used strain designation system. The information can be used to reconsider the current breeding practice. Beyond that, Syrian Arabian horses are an important reservoir for genetic diversity.

Collective motion of groups of self-propelled particles following interacting leaders

In order to keep their cohesiveness during locomotion gregarious animals must make collective decisions. Many species boast complex societies with multiple levels of communities. A common case is when two dominant levels exist, one corresponding to leaders and the other consisting of followers. In this paper we study the collective motion of such two-level assemblies of self-propelled particles. We present a model adapted from one originally proposed to describe the movement of cells resulting in a smoothly varying coherent motion. We shall use the terminology corresponding to large groups of some mammals where leaders and followers form a group called a harem. We study the emergence (self-organization) of sub-groups within a herd during locomotion by computer simulations. The resulting processes are compared with our prior observations of a Przewalski horse herd (Hortobágy, Hungary) which we use as results from a published case study. We find that the model reproduces key features of a herd composed of harems moving on open ground, including fights for followers between leaders and bachelor groups (group of leaders without followers). One of our findings, however, does not agree with the observations. While in our model the emerging group size distribution is normal, the group size distribution of the observed herd based on historical data have been found to follow lognormal distribution. We argue that this indicates that the formation (and the size) of the harems must involve a more complex social topology than simple spatial-distance based interactions.

Sequential stable isotope analysis reveals differences in multi-year dietary history of three sympatric equid species in SW Mongolia.

Summary Competition among sympatric wild herbivores is reduced by different physiological, morphological and behavioural traits resulting in different dietary niches. Wild equids are a rather uniform group of large herbivores which have dramatically declined in numbers and range. Correlative evidence suggests that pasture competition with livestock is one of the key factors for this decline, and the situation may be aggravated in areas where different equid species overlap.The Dzungarian Gobi is currently the only place where two wild equid species coexist and share the range with the domesticated form of a third equid species. In the winter‐cold Gobi desert pasture productivity is low, highly seasonal, and wild equids additionally face increasing livestock densities.We used stable isotope chronologies of tail hairs to draw inferences about multi‐year diet seasonality, isotopic dietary niches and physiological adaptations in the Asiatic wild ass (khulan), re‐introduced Przewalski's horse, and domestic horse in the Mongolian part of the Dzungarian Gobi.Our results showed that even in the arid Gobi, both horse species are predominantly grazers, whereas khulan are highly seasonal, switching from being grazers in summer to mixed feeders in winter. The isotopic dietary niches of the two horse species were almost identical, did not vary with season as in khulan and were narrower than in the latter. Higher δ15N values point towards higher water use efficiency in khulan, which may be one reason why they can exploit pastures further away from water. Synthesis and applications. The high degree of isotopic dietary niche overlap in the two horse species in the Mongolian Gobi points towards a high potential for pasture competition during the critical nutritional bottleneck in winter and highlights the need to severely restrict grazing of domestic horses on the range of the Przewalski's horses. The evolutionary more distant khulan are less constrained by water and seem more flexible in their choice of diet or less successful in exploiting grass‐dominated habitats in winter due to human presence. Providing additional water sources could increase the competition between khulan and livestock and should, therefore, only be done following careful consideration.

Parasites observed in the proximal alimentary tract of a Przewalski's horse in China

SummaryThis article reports a Przewalski's horse from the Kalamaili Nature Reserve (KNR) in China transported to our institute to determine the cause of death. The animal had been subjected to necropsy before being transported to our institute; the entire digestive tract was removed but not opened to reduce the possible loss of parasites. During examination, ascarids in the intestines and bots in the oral cavity and stomach were observed. The parasites were identified according to an identification key and enumerated. The ascarids were identified as Parascaris spp. and were associated with a volvulus, resulting in intestinal obstruction. A total of two (stomach), one (duodenum) and 106 (intestines) Parascaris spp. were counted. Bots in the digestive tract were identified as third stage larvae of Gasterophilus pecorum (G. pecorum), Gasterophilus nigricornis (G. nigricornis) and Gasterophilus nasalis (G. nasalis), which may have been associated with stomach ulcers suffered by the horse. Attached to the lining of the oral cavity and stomach were 331 and 2014, respectively, larvae of G. pecorum, while in the duodenum there were 23 third stage larvae of G. nigricornis and 20 third stage larvae of G. nasalis. Therefore, the possibility of the presence of these parasites should not be overlooked in Przewalski horses as these parasites may be responsible for severe clinical signs in infected animals.

ACUTE PHASE PROTEINS AS A MARKER OF RESPIRATORY INFLAMMATION IN PRZEWALSKI'S HORSE (EQUUS FERUS PRZEWALSKII).

Acute phase proteins are sensitive markers of inflammation, which are highly conserved across taxa. Although the utility of these proteins are becoming well defined in human and domestic animal medical fields, their role in nondomestic species remains unclear. In this communication, a 20-yr-old Przewalski's horse was presented for unresolving aspiration pneumonia, which cultured a unique Actinomyces-like bacteria. Despite waxing and waning clinical signs and minimal changes on baseline hematologic analysis, protein electrophoresis, serum amyloid A, and surfactant protein D serum concentrations showed changes that more accurately reflected the clinical severity of this case.

Distribution of coat-color-associated alleles in the domestic horse population and Przewalski's horse.

Considering the hidden mode of inheritance of some coat-color-associated alleles, we investigated the presence/absence of coat-color-associated alleles in 1093 domestic horses of 55 breeds and 20 specimens of Przewalski's horse. For coat-color genotyping, allele specific PCR, pyrosequencing and Li-Cor analyses were conducted on 12 coat-color-associated alleles of five genes. Our data provide deep insight into the distribution of coat-color-associated alleles within breeds. We found that the alleles for the basic colorations (bay, black, and chestnut) are widely distributed and occur in nearly all breeds. Alleles leading to dilutions or patterns are rare in domestic breeds and were not found in Przewalski's horse. Higher frequencies of these alleles are only found in breeds that are selected for their expressed phenotypes (e.g., Kinsky horse, Lewitzer, Tinker). Nevertheless, our study produced strong evidence that molecular testing of the coat color is necessary for well-defined phenotyping to avoid unexpected colorations of offspring that can result in legal action.

Equine atypical myopathy associated with sycamore seed ingestion in a Przewalski foal

One of the 172 UK cases of equine atypical myopathy (EAM) reported to the Atypical Myopathy Alert Group (AMAG) in 2014 was that of a five-month old male Przewalski horse (Equus ferus przewalskii), resident at ZSL Whipsnade Zoo, UK. The foal presented initially with sudden-onset and repeated stretching of the neck as if dysphagic, with progressive weakness (including lying down), sweating and an unresponsive demeanour. General anaesthesia, induced with a combination of etorphine, midazolam and hyaluronidase, was required for each examination and subsequent treatment of the foal. Initial biochemical analysis showed a markedly increased plasma creatine kinase (CK) activity of 105,001 U/L, an increased aspartate amino transferase (AST) activity of 4194 U/L and a mildly increased inorganic phosphorus concentration of 2.35 mmol/L. The foal was unresponsive to treatment and had to be euthanased. Skeletal musculature and the myocardium showed the most significant pathological changes, with histological evidence of rhabdomyolysis, whilst urine organic acid analysis and an abnormal organic acid serum profile were supportive of multiple acyl Co-A dehydrogenase deficiency typical of EAM. This is the first description of EAM in a non-domestic equid.

Seasonal Changes in Body Condition of Przewalski's Horses in a Seminatural Habitat

Identification of the normal fluctuations in body condition of equids is important for the monitoring and management of wild and feral equid populations. Knowledge of the causative factors and implications of body condition fluctuations may allow managers to better respond with interventions when body condition fluctuations are unseasonal or extreme. The body condition score (BCS) of 33 adult Przewalski's horses (22 mares and 12 harem stallions) roaming freely in a population in excess of 300 in the Hortobágy Puszta in Hungary was assessed weekly for 12 months from January to December 2009. Mares had a higher mean BCS than stallions for each month of the year, and all horses maintained a moderate to fleshy condition score. There were two peaks and two troughs in BCS for both mares and stallions. It appears that an annual fluctuation of body condition of Przewalski's horses is normal for horses living in a semiwild habitat. This can be explained by seasonal variation in pasture quality, an energy cost to mares in late gestation and early lactation, and a large energy cost to mares and stallions in protecting new born offspring from aggressive attacks by rival stallions and the work of band stallions protecting against challenging stallions. Although there was a seasonal fluctuation in body condition, semiwild horses living in a former wild horse habitat were never in poor condition. Managers of domestic, feral, and wild horses may tolerate a small reduction in body condition of horses during the annual seasonal cycle.

Identification of genes with nonsynonymous SNP in Jeju horse by whole-genome resequencing reveals a functional role for immune response.

Jeju horse (Natural Monument number 347) is a breed of horse that has experienced long-term isolation and domestication in Jeju Island, South Korea. We evaluated genetic features of this breed, including SNP, by whole-genome resequencing using an Illumina HiSeq 2000. A total of 5,986,852 SNP were identified in 4 Jeju horses and were divided into homozygous and heterozygous SNP (2,357,099 and 3,629,753 SNP, respectively). It revealed that 63.8% of these SNP resided in intergenic regions. Immune response genes with nonsynonymous SNP were overrepresented in Jeju horses as evidenced by Gene Ontology clustering. Among these genes, Toll-like receptors (TLR) are highly enriched. Comparing TLR genes between Jeju horses and the Przewalski's horse, and genes showed "possibly damaging" mutations in several regions by analysis with PolyPhen-2. These results provide a framework for further genetic studies in Jeju horse by domestication. Furthermore, research on functions of SNP-associated genes would aid in understanding the molecular genetic variation of horse breeds.

A preliminarily assessment of landscape factors affecting habitat use by Przewalski horses and habitat evaluation in Hustai National Park, Mongolia

Przewalski horses (Equus ferus przewalskii) bred in captivity in foreign zoos have been reintroduced to Hustai National Park (HNP) in Mongolia. To successfully return horses to their former wild habitat, we need reliable information regarding their habitat use. Hence, the purposes of this study were to examine the landscape context affecting habitat use by Przewalski horses and to identify potential suitable habitat areas in HNP. To clarify the factors affecting the horses’ habitat use, we constructed a generalized linear model (GLM) based on fecal counts taken from 48 randomly sampled field plots in HNP. The fecal number counted in each plot was defined as the dependent variable in the model, and we included seven explanatory variables that may affect Przewalski horses’ habitat use: distance to a river, distance to forest, distance to a road, slope, difference of elevation with surroundings, number of plant communities, and presence of dominant forage plant categories. Finally, we used the most parsimonious model to identify potential suitable habitat areas on a cell-based map of HNP. The GLM that best explained fecal density was the full model containing all explanatory variables, indicating that Przewalski horses’ habitat use is influenced by resources essential to maintaining their survival and by the livelihood of risk. According to our habitat evaluation based on the most parsimonious model, it appears that suitable habitat areas were scattered in the outer side of HNP. These results indicate that Przewalski horses could extend their habitat area beyond their current distribution.

The incidence and species composition of Gasterophilus (Diptera, Gasterophilidae) causing equine myiasis in northern Xinjiang, China

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 in Przewalski’s horse (Equus ferus przewalskii), and 1785 in the domestic horse (Equus ferus caballus). Six species of Gasterophilus were identified, with the following proportions of overall parasite abundance: Gasterophilus pecorum 88.94%, Gasterophilus nigricornis 4.94%, Gasterophilus nasalis 3.93%, Gasterophilus haemorrhoidalis 1.91%, Gasterophilus intestinalis 0.19%, and Gasterophilus inermis 0.087%. A majority of equines (n=32, 35.57%) was infested with five Gasterophilus species, while 29 animals (32.22%) harboured four species, 13 animals (14.44%) had six, 12 animals (13.33%) had three, three (3.33%) had two, and one (1.11%) had only one species. The percentage of Przewalski's horses infested was higher than local domestic horse or Mongolian wild ass.

野放普氏野马（Equus przewalskii）家域面积及其影响因素

PDF HTML阅读 XML下载 导出引用 引用提醒 野放普氏野马(Equus przewalskii)家域面积及其影响因素 DOI: 10.5846/stxb201402090224 作者: 作者单位: 新疆大学资源与环境科学学院,新疆大学,新疆大学资源与环境科学学院,新疆卡拉麦里山有蹄类自然保护区阿勒泰管理站,新疆卡拉麦里山有蹄类自然保护区阿勒泰管理站,中国科学院动物研究所,中国科学院动物研究所 作者简介: 通讯作者: 中图分类号: 基金项目: 新疆自治区科技支撑计划项目(201233131);卡拉麦里山有蹄类自然保护区阿勒泰管理站中央财政森林生态效益补偿基金;科技基础性工作专项重大项目(2013FY110300) Factors affecting the home range of reintroduced Equus przewalskii in the Mt. Kalamaili Ungulate Nature Reserve Author: Affiliation: College of Resource and Environmental Sciences, Xinjiang University,College of Resource and Environmental Sciences, Xinjiang University,,,,,Institute of Zoology (IOZ), Chinese Academy of Sciences (CAS) Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:采用MCP方法研究了2011年至2012年新疆卡拉麦里山有蹄类自然保护区野放普氏野马家域的变化。通过方差分析验证了年间、季节间不同群体家域及其两两重叠无差异。以家族群大小为协变量进行了野放野马家域协方差分析。利用野放野马家族大小为协变量的协方差分析分析检验了野放野马家族大小与家域关系。结果表明:(1)野马平均家域面积由2011年的(20±2) km2/匹扩大到2012年的(30±2) km2/匹。对部分野放群体中头马未发生更替的野马群的研究表明,随着野马群体增大,其家域面积显著增大(P < 0.05)。(2)单因素方差分析显示,不同野马群的家域面积在不同年份差异显著,且春季家域>秋季家域>夏季家域。(3)2011年不同群家域两两间相互重叠面积与群大小无显著相关(r=0.256, P=0.580>0.05)。而2012年野马群家域两两之间重叠面积有显著差异(F=4.521,d f=8, P < 0.001)。家域两两相互重叠面积与群大小显著相关(r=0.706, P=0.033<0.05)。(4)不同季节间野马群家域重叠面积有显著差异(F=5.695,d f=8, P < 0.001)。5号群、7号群和8号群的自身家域重叠面积(P < 0.05),3号群、6号群和9号群的家域重叠面积(P < 0.05)。(5)影响野放野马家域面积的生物因子有草本盖度、灌木盖度,非生物因子主要有温度、湿度、风速、最近水源地距离和最近居民点距离等。温度与草本盖度是影响野放野马家域面积大小的主要因素,两者与野放野马家域面积显著相关(P < 0.01)。 Abstract:The number of Przewalski's horses(Equus przewalskii) released increased from 84 in 2011 to 96 in 2012 in the Mt. Kalamaili Ungulate Nature Reserve. We characterized the home ranges of released Przewalski's horses and studied the factors affecting the ranges. The home ranges were calculated using the minimum convex polygon(MCP) method. We used a nested ANOVA to determine whether there were differences between home ranges, and regions of overlap between two home ranges of wild horses among seasons and years. We also used family size as a covariate to test the impact of family size on home ranges using ANCOVA. We found the following results:(1) the home ranges of released Przewalski's horses increased in area from(20±2) km2(mean±SE) in 2011 to(30±2) km2 in 2012. The home ranges of families with the same head stallion did not change significantly between 2011 and 2012(P < 0.05).(2) ANOVA indicated that home ranges differed significantly among families. The home ranges of horse families were significantly different, were larger in the spring than in the autumn, and were the smallest in the summer.(3) The area of home range overlap between pairs of wild horses was not correlated with family size(r=0.256, P=0.580) in 2011. However, the area of overlap between pairs of wild horses was correlated with family size in 2012(F=4.521, d f=8, P < 0.001). Home range overlap and family size were significantly positively correlated(r=0.706, P=0.033).(4) Regions of home range overlap between wild horses were significantly different among seasons(F=5.695, d f=8, P < 0.001). The regions of overlap in seasonal home ranges for families 5, 7, and 8 were significantly larger(P < 0.05) than those for families 3, 6, and 9(P < 0.05).(5) The main biological factors that affected the home range of wild horses were herb coverage and shrub coverage, and the non-biological factors were mainly temperature, humidity, wind, the shortest distance to a water source, and distance to the nearest human settlement. Temperature and shrub cover were two major factors that influenced the home ranges of reintroduced Przewalski's horses, and both factors were significantly correlated with the home range areas of wild horses(P < 0.01). Domestic research on wildlife home ranges has been interdisciplinary in nature, and previous investigations have led to the progressive development of large-scale multidisciplinary studies. Furthermore, research tools have advanced from records of single manual observations to computer-based methods, including 3S technology(i.e., RS, GPS, and GIS). Estimates of home range sizes can help researchers determine wildlife habitat preferences, and 3S technology is widely used to protect wildlife. Finally the methods for calculating home ranges of wild animals are becoming more diverse. Przewalski's horses are a flagship species for biodiversity in the Junggar Basin. Their reintroduction has attracted widespread interest at home and abroad. At the end of 2012, the number of reintroduced Przewalski's horses increased to 96(from 84 in the previous year). Therefore, it is necessary to study changes in the home range of wild Przewalski's horses in detail in order to provide scientific guidance for the protection of wildlife in protected areas as well as in the Mt. Kalamaili Ungulate Nature Reserve desert region of Xinjiang, China. 参考文献 相似文献 引证文献