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1.
Red-crowned cranes Grus japonensis, which are an endangered species, have two separate populations, a mainland population in the Eurasian continent and an island population in eastern Hokkaido, Japan. Island cranes showed three haplotypes (Gj1, Gj2 and Gj13), whereas ten haplotypes (Gj3–Gj12) were confirmed in captive cranes and stray cranes. We found Gj5 haplotype in feathers of two cranes as well as four new haplotypes in seven wild crane feathers collected in South Korea. We also found feathers in the nest in Sarobetsu Wetland in northwestern Hokkaido. While the haplotype of female-derived feathers was Gj2, that of male-derived feathers was Gj5. The results suggest that there has been crossbreeding between cranes in the island population and cranes in the mainland population.  相似文献   

2.
ABSTRACT

The Norwegian coastal goat is a national and endangered breed. Coastal goat populations are mainly divided with a large mainland and two small island populations. The objective of this study is to describe genetic diversity in the feral Skorpa island population and its relationship to the mainland coastal goat population (Selje) using the Norwegian milk goat population as a reference. Analyses were based on 96 samples genotyped by the CaprineSNP50 Beadchip from three populations; 7 Skorpa (SK), 37 Selje (SE) and 52 Norwegian milk goats (MG). The SK population had significantly less genetic variation and higher levels of inbreeding than the two other populations. It was more distant from the two mainland populations than they were from each other. The marginal contribution of the SK population to genetic diversity was small. Means of introducing genetic diversity into the SK population should be considered if the population is prioritized for conservation.  相似文献   

3.
The geographical variations of the skulls were osteometrically examined in the gray-bellied squirrel (Callosciurus caniceps) from the populations of Korat, Ranong, southernmost Thailand, and Terutau Island. The skull size was larger in northern population than in the southern population in the continental mainland. The zoogeographical influences of the Isthmus of Kra remained unclear, since the plots from Korat population were intermingled with those from southernmost Thailand population in the principal component charts. Although Korat population has been thought to belong to north group, we suggest that Ranong and southernmost Thailand populations may contain individuals from both north and south groups separated by the ancient Kra barrier. Terutau Island population was similar to southernmost Thailand population in skull size, although Terutau population has been isolated in the island and separated from the south group of the Isthmus of Kra. In the proportional analysis the interorbital space was narrower and the binocular sense has been well-developed in Terutau population. It suggests that this population has been highly adapted to arboreal behavior. In contrast, the skull with larger interorbital space was more adaptive for terrestrial life in Korat population. The canonical discriminant analysis could clearly separate the four populations in the scattergrams of discriminant scores.  相似文献   

4.
The giant panda faces severe threats from habitat fragmentation and isolation. Currently, giant panda populations have been fragmented into 30 habitat patches. The disappearance of isolated small populations and studies on the genetic diversity of various populations have shown that small isolated panda populations are at a high risk of dying out completely. Habitat fragmentation has seriously impaired the ability of the giant panda to resist climate changes and other natural disasters, such as large‐scale, synchronous bamboo blooming. The Min Mountains have the largest population of pandas in China, numbering 581 individuals and accounting for 52% of the total (1114) in China. Geographic isolation means that giant pandas in the Min Mountains are divided into two populations (population A in the north and population B in the south). Population B, which had only 42 individuals in 1989, is severely threatened by high‐density human populations and the loss of genetic diversity. However, we have identified an important corridor connecting the two populations. This paper explains the importance and the feasibility of reestablishing this corridor. Due to the special geographic locations of these two populations (two rivers block the migration of giant pandas between south and north), the corridor is the only passage for giant pandas in the region. Recent studies have also shown an increase of giant panda activity in the area of the corridor. However, vegetation in the corridor has been severely degraded. Bamboo forest must be restored in this area to provide food for the pandas during migration. The effects of human activities must be reduced in order to maintain panda habitat. We believe that a restored corridor will be of great benefit to the survival of giant pandas in the Min Mountains, especially for population B. Successful re‐establishment of a corridor will be a valuable model for corridor construction in the future.  相似文献   

5.
Breeding success (fledglings pair?1 y?1) of the Red-listed African Black Oystercatcher (Haematopus moquini) is highly variable, both spatially and temporally. Despite a diversity of natural factors causing this variability, there is evidence that two anthropogenic factors, i.e. disturbance and an introduced mussel (Mytilus galloprovincialis), are having an impact on the local breeding success of this species. Using a data set comprising 87 site-years of nest-monitoring data across most of the species’ breeding range, we analysed the extent and causes of variability in breeding success. Breeding success differed across three population categories defined by varying levels of human disturbance: island populations, protected mainland populations, and unprotected mainland populations. Differences in breeding success between island populations and protected mainland populations were likely due to differing exposure to predators; however, differences between protected and unprotected mainland populations were unlikely caused by this as both experience equivalent predation levels (although from different predators). Protection only improved the breeding success of oystercatchers in very high-quality habitats (with a high biomass of alien mussels), and where populations were ‘released’ from high levels of human disturbance. In unprotected mainland areas, human activity impacted on the breeding success of local populations primarily through predation of small chicks by uncontrolled dogs, and by rising tides drowning chicks that were hiding from human disturbance. The findings of this study note the potential conservation dilemma resulting from an invasive species improving the conservation status of a Red-listed species, and encourage the implementation of restricted sites in high-quality habitats with high breeding pair densities.  相似文献   

6.
Skulls of the red-cheeked squirrel (Dremomys rufigenis) from various geographical locations: Malaysia (peninsular area), Vietnam (south district)-Laos, and Thailand (north district) were osteometrically examined. The skull size of the squirrels in the southern (Malaysia) population was fundamentally larger than that in the northern (Vietnam, Laos and Thailand) populations. The proportion indices indicated that the splanchnocranium was relatively longer in the Malaysia population, and that the interorbital space was narrower in Vietnam-Laos, and Thailand populations. We suggest that the long nose and laterally-oriented orbits in the skull may be better adapted for terrestrial-insectivorous life in the Malaysia population and the binocular sense facilitated by rostrally-oriented eyes contributes to the arboreal-fruit eating behavior in the two northern populations. The Malaysia population was clearly distinguished from the other populations by the principal component analysis. We suggest that the geographical barrier of the Isthmus of Kra influences the morphological variation of the skull among the squirrel populations.  相似文献   

7.
We examined the geographical variation of the skull size and shape of the lesser mouse deer (Tragulus javanicus) from Laos, Thailand, Peninsular Malaysia, Sumatra, Java, Borneo, Langkawi and some Islands of Tenasserim in Myanmar. Although the influence of the climatic condition on skull size was not confirmed in the mainland populations, the skull became rostro-caudally longer in the populations of Tenasserim and Sumatra because of island isolation effect. The skull size was classified into the following three clusters of localities from the matrix of Q-mode correlation coefficients: 1) Langkawi and Tenasserim, 2) Laos and Thailand, 3) Sumatra and Borneo. The skulls in the population of Java belong to the cluster of Langkawi and Tenasserim in male, however were morphologically similar to those in the cluster of Borneo and Sumatra. The canonical discriminant analysis pointed out that the Laos and Tenasserim populations were separated from the other ones and that the populations of Sumatra, Java and Borneo were intermingled each other.  相似文献   

8.
Geographical variation was examined morphologically in the common tree shrew (Tupaia glis) in some Indochinese and Malayan regions. Osteometrical examination and principal component analysis elucidated the morphological differences among various populations. The populations from southern and western Thailand were distinguished morphologically from the other populations. Variation in males from south Thailand and Kuala Lumpur suggests that the Isthmus of Kra may have an influence on the variation of skull morphology. However, the Isthmus of Kra was not completely considered as a factor of geographical separation in this species, because we could not confirm the separation in skull size and shape between the localities at least in females. While, the Kanchanaburi population in western Thailand was significantly smaller than the other population in skull size, and constituted the morphologically separable group in our study.  相似文献   

9.
We investigated the prevalence of 30 known virulence factor genes (VFGs) in uropathogenic E. coli (UPEC) from two geographically distinct feline populations, using a PCR-based approach. E. coli isolates were also subjected to macrorestriction analysis to assess their phylogenetic relationships. VFG profiles differed considerably according to the geographic origin of the isolates, enabling discriminant analysis to correctly predict population membership for 15/15 NZ isolates and 18/22 UK isolates. The prevalence of gene markers for P-fimbriae (PapA, PapC, PapEF, and PapG III), colicin V (CvaC), increased serum survival factor (Iss), complement resistance factor (TraT), pathogenicity-associated island (MalX), iron-regulated siderophore receptor (IreA) and haemolysin (HlyD) differed significantly between UK and NZ isolates. Significant phylogenetic differences between the two populations were also identified, but VFG profiles could not be predicted on the basis of phylogenetic relationships. Consequently, a geographically uneven distribution of certain virulence genes, independent of phylogeny, is the likely cause of VFG differences between populations. We cannot rule out that subtle differences in patient disease status may have contributed to the dissimilarity of VFG profiles.  相似文献   

10.
Bartonella rochalimae (B.r.) and Bartonella vinsonii subsp. berkhoffii (B.v.b.) have been isolated from gray foxes (Urocyon cinereoargenteus) in mainland California and high Bartonella seroprevalence was reported in island foxes (U. litorralis), especially from Santa Cruz and Santa Rosa Islands. As a follow-up study, the objectives were to determine the prevalence of Bartonella bacteremia and seropositivity and to identify the Bartonella species infecting a convenience sample of 51 island foxes living on Santa Rosa Island. Using an immuno-fluorescence antibody test directed against B.v.b and Bartonella clarridgeiae (B.c.), used as a substitute for B.r., the overall antibody prevalence was 62.7% with 16 (31.4%) foxes seropositive for B.c. only, 5 (9.8%) for B.v.b. only, and 11 (21.6%) for both antigens. B.v.b. was isolated from 6 (11.8%) foxes using blood culture medium. An additional seropositive fox tested PCR positive for B.v.b. and 3 other seropositive foxes tested PCR positive for B. rochalimae. All of the isolated B.v.b. colonies and the B.v.b. PCR positive sample belonged to type III, the same type found to infect mainland gray foxes. Therefore, Bartonella infection is widespread within this island fox population with evidence for B.v.b. type III reservoir host-specificity. Presence of B. rochalimae in the Channel Islands has been detected for the first time using PCR.  相似文献   

11.

Ethiopia is home to a diverse gene pool of indigenous sheep populations. Therefore, a better understanding of genetic variation holds the key to future utilization through conservation. Three of these breeds, Afar, Blackhead Somali, and Hararghe Highland, are found in eastern Ethiopia where they contribute significantly to the livelihood of most pastoralist, agro-pastoralist, and smallholder farmers. These indigenous sheep are recognized on the basis of morphotype and their genetic distinction remains unknown. Here, to assess genetic variation, and matrilineal genetic origin and relationship of fat-rumed sheep found in eastern Ethiopia, 300 individuals from the three breeds were genotyped for 22 microsatellite markers and sequenced for the mitochondrial DNA displacement loop (mtDNA d-loop) region. The overall HO and HE were 0.57 and 0.75, respectively. Differentiation statistics revealed that a high proportion (97%) of the total genetic variation was explained by differences between individuals within populations. Genotype assignment independent of the population of origin showed K?=?2 to be the optimum number of genetic backgrounds present in the dataset. This result was further confirmed by mtDNA D-loop sequences comparison in which the matrilineal genetic origin of eastern Ethiopia sheep is from two haplotype groups (types A and B) among the five haplotypes globally observed. Taken together, our findings suggest that the sheep populations from three breeds originated from two ancestral genetic backgrounds that may have diverged prior to their introduction to Ethiopia. However, to obtain a complete picture of the evolutionary dynamics of Ethiopian indigenous sheep, more samples and populations from within and outside of the country will need to be analyzed.

  相似文献   

12.
In the last 7 yr, three different species of terrestrial mammals were diagnosed with Mycobacterium pinnipedii either within one collection or through the introduction of an infected animal from another zoo. The affected species included the Malayan tapir (Tapirus indicus), Bactrian camel (Camelus bactrianus bactrianus), and crested porcupine (Hystrix cristata). In the first zoo, all of these were living in exhibits adjacent to a group of South American sea lions (Otariaflavescens) and were cared for by the same keeper. One infected tapir was transferred to a different zoo and transmitted M. pinnipedii infection to three other Malayan tapirs. The tapirs were tested with various diagnostic methods, including comparative intradermal tuberculin test, PCR and culture of sputum samples, Rapid Test (RT), and multiantigen print immunoassay (MAPIA). The M. pinnipedii infection was confirmed at postmortem examination in all animals. RT and MAPIA showed the diagnostic potential for rapid antemortem detection of this important zoonotic disease.  相似文献   

13.
《家畜生态学报》2013,34(7):10-14
In order to elucidate the genetic differences between Puer Miaojiao and Nanjian Lver black bone chicken, the hypervariable region I sequence variations in mtDNA D loop of the respective 48 random samples from Puer Miaojiao and Nanjian Lver black bone chicken were examined by direct sequencing of PCR products in the present study, and an analysis of population genetics and phylogenetics were conducted on the data obtained. In Puer Miaojiao black bone chicken, a total of 24 polymorphic sites included 2 singleton polymorphic sites and 24 parsimony informative sites were detected, which defined 12 haplotypes and the unique haplotypes accounted for 50%. The haplotype diversity, nucleotide diversity and the average genetic distance within the population were 0.829±0.039,0.01559±0.00068 and 0.016±0.003, respectively. In Nanjian Lver black bone chicken, a total of 28 polymorphic sites included 0 singleton polymorphic site and 28 parsimony informative sites were detected, which defined 13 haplotypes and the unique haplotypes accounted for 53.85%. In this population, the haplotype diversity, nucleotide diversity and the average genetic distance within the population were 0.907±0.018,0.01590±0.00056 and 0.016±0.003, respectively. Phylogenetic and genetic divergence analysis revealed that there were A,B,E,F and G five matrilineages in Puer Miaojiao black bone chicken which accounted for 45.83%,2.08%,8.33%,16.67% and 27.09%, respectively. And there were A,B,C, E,F and G six matrilineages in Nanjian Lver black bone chicken which accounted for 22.92%,14.58%,4.17%,10.42%,16.67% and 31.25%, respectively. The results in this study indicated that the population genetic variation in Nanjian Lver black bone chicken are higher than that in Puer Miaojiao black bone chicken and the population genetic composition for the two chicken populations were significantly different. They are mainly for the native chicken descent by birth, but there may be a small amount of commercial chicken blood mixed.  相似文献   

14.
With the completion of the draft assembly of the giant panda genome sequence, RNA sequencing technology has been widely used in genetic research on giant pandas. We used RNA-seq to examine black and white hair follicle samples from adult pandas. By comparison with the giant panda genome, 75 963 SNP loci were labeled, 2426 differentially expressed genes (DEGs) were identified, and 2029 new genes were discovered, among which 631 were functionally annotated. A cluster analysis of the DEGs showed that they were mainly related to the Wnt signaling pathway, ECM–receptor interaction, the p53 signaling pathway, and ribosome processing. The enrichment results showed that there were significant differences in the regulatory networks of hair follicles with different colors during the transitional stage of hair follicle resting growth, which may play a regulatory role in melanin synthesis during growth. In conclusion, our results provide new insights and more data support for research on the color formation in giant pandas.  相似文献   

15.
NDV La Sota株、V4株F蛋白表位的预测   总被引：4，自引：0，他引：4  
为进一步研究2种疫苗的表位,以深入探讨NDV La Sota株、V4疫苗免疫差异的根本所在。应用亲水性、可及性、抗原性、可塑性和二级结构预测等5种参数分别对新城疫病毒La Sota株和V4株F蛋白的B细胞抗原表位进行了综合预测,预测到二者的B细胞抗原表位分别有19个,这些表位中含有已经确定的5个中和表位,A1：72aa,A2：78aa,A3：79aa,A4：157aa、161aa、170aa、171aa,A5：343aa。比较发现,二者有9个预测的B细胞表位氨基酸序列存在差异。  相似文献   

16.
本研究采用电感耦合等离子质谱(ICP-MS)方法,测定福建漳浦菜屿岛黄嘴白鹭(Egretta eulophotes)排泄物的重金属元素(V、Cr、Mn、Ni、Cu、Zn、Cd、Se、Pb)及半金属元素(As)的含量,分析比较黄嘴白鹭繁殖之前和繁殖之后的集群营巢地、非营巢地的表层土壤的重金属元素及半金属元素含量的变化.结果显示:在本次测定的所有排泄物和土壤样本中均未检出元素Se和Cd:非营巢地土壤中各元素的含量在繁殖前后都没有显著差异(p>0.05),营巢地土壤中的Zn和Pb元素的含量在繁殖前后有极显著差异(p<0.01).营巢地和非营巢地土壤之间的元素含量比较结果发现,繁殖之前两地土壤之间的Zn含量存在极显著差异(p<0.01);繁殖之后两地土壤之间的Cu、Zn、As、Pb存在极显著差异(p<0.01),V、Ni存在显著差异(p<0.05).上述数据说明黄嘴白鹭的集群繁殖活动对湿地和海岛生态系统之间的重金属转移起着重要作用,长时间则可能造成海岛营巢地土壤的重金属污染.  相似文献   

17.
The geographical variation of the gray-bellied squirrel (Callosciurus caniceps) was examined using osteometry of skull in Southeast Asia. From the principal component analysis (PCA), the plots of the northern localities from Nan to Kanchanaburi and those of the southern localities from Narathiwat to Kuala Lumpur in male were completely separated. In female, the plots of the locality from Uttradit to Kanchanaburi and those of the locality from Pattani to Negri Sembilan were completely separated. We called these northern localities and southern localities which are distinguished by the PCA as N group and S group. The size and shape of the skulls of these squirrels indicated the differences between N group and S group from t-test and U-test. These results may be influenced by the two transitions of the phytogeography around the southernmost locality in N group and the northernmost locality in S group in the peninsular Thailand and Malay Peninsula. Localities which are located between N and S groups were called the Middle (M) group. From the PCA among N, S groups and each locality of M group, the plots of localities such as Prachuap Khiri Khan, Chumphon, Krabi, Nakhon Si Thammarat and Trang in both sexes of M group could not be separated from those of N and S groups. We suggest that the sympatric distribution of N and S groups and the hybrid of N and S populations may be seen in these localities of M group.  相似文献   

18.
Since we have clarified the manipulation mechanism using the radial sesamoid (RS) in the giant panda (Ailuropoda melanoleuca), our aim in this study is to examine the position, shape and function of the RS morphologically, and to observe the attachment to the RS of the M. abductor pollicis longus and the M. opponens pollicis in the other Ursidae species. So, we focused on the carpus and manus of the polar bear (Ursus maritimus) and the brown bear (Ursus arctos) in this study. The RS was tightly articulated to the radial carpal, and could not adduct-abduct independently of the radial carpal. The M. abductor pollicis longus tendon and the M. opponens pollicis belly were attached to the RS, independently. In the polar bear, the deep concave and the flat surface were confirmed in attachment area for these two muscles. The morphological relationship between the RS and the M. abductor pollicis longus and the M. opponens pollicis in the two species of bears were essentially consistent with that in the giant panda. It also demonstrated that the manipulation mechanism of the giant panda has been completely based on the functional relationship between the small RS, and the M. abductor pollicis longus and the M. opponens pollicis in Ursidae species.  相似文献   

19.
OBJECTIVE: To estimate the frequency of serum antibodies (IgG and IgM) to canine coronavirus (CCV) in the Australian dog population and evaluate the role of CCV as a causative agent of gastroenteritis. DESIGN: A serological survey of antibodies to CCV among different dog populations. PROCEDURE: The development and characterisation of an indirect ELISA for the detection of antibodies (IgG and IgM) to CCV was undertaken. Sera collected from both diarrhoeal and non-diarrhoeal dogs from various populations throughout Australia were tested for these antibodies to CCV. RESULTS: Serum samples (1396) collected from 1984 to 1998 were tested for the presence of IgG antibodies to CCV. Samples were divided into two categories on the basis of the number of dogs housed together. The groups were either an open population containing dogs housed as groups of three or less, or kennel populations. Sera from 15.8% of the open population and 40.8% of kennelled dogs were positive for CCV antibodies. The prevalence of antibodies varied from zero to 76% in kennelled dogs. About 23% of 128 dogs positive for IgG antibodies to CCV were also positive for IgM antibodies to CCV, indicating recent CCV infection. Of those dogs that were presented with clinical signs of gastroenteritis such as diarrhoea and vomiting (n = 29), 85% were positive in the IgM ELISA and 85.7% in the IgG ELISA for antibodies to CCV. In comparison, for those dogs presented without any history of gastroenteritis only 15% were positive for IgM and 30% positive for IgG. CONCLUSION: Serological evidence indicates that infection with CCV in dogs is widespread throughout the Australian mainland. The prevalence of antibodies varies greatly among different populations, with an average of 40.8% positive in kennelled populations and 15.8% in the open population.  相似文献   

20.
One hundred wild boars (Sus scrofa) from a geographically isolated population on the island Saaremaa of western Estonia were examined for visceral helminths. Seven helminth species, Metastrongylus pudendotectus, M. salmi, M. elongatus, Ascaris suum, Trichuris suis, Dicrocoelium dendriticum and Taenia hydatigena larva, were found. The predominant helminths discovered were lung nematodes (prevalence 82%, mean intensity 96.2 per animal). A significant negative correlation was observed between the weight of wild boars and the number of lungworms and helminth species. The number of helminth species found in the wild boar population on the island was lower compared to that of the adjacent mainland.  相似文献   

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