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61.
The minimization of kinship in captive populations is usually achieved through the use of pedigree information. However, pedigree knowledge alone is not sufficient if pedigree information is missing, questionable, or when the founders of the captive population are related to one another. If this is the case, higher levels of inbreeding and lower levels of genetic diversity may be present in a captive population than those calculated by pedigree analyses alone. In this study, the genetic status of the critically endangered Mississippi sandhill crane (MSC) (Grus canadensis pulla) was analyzed using studbook data from the U.S. Fish and Wildlife Service managed captive breeding program as well as microsatellite DNA data. These analyses provided information on shared founder genotypes, allowing for refined analysis of genetic variation in the population, and the development of a new DNA-based studbook pedigree that will assist in the genetic management of the MSC population.  相似文献   
62.
Forty-three microsatellite loci originally isolated in Grus americana and G. japonensis were tested for polymorphism in the blue crane (G. paradisea). Amplified products were sequenced in the blue crane to aid in the design of blue crane-specific primers. When characterized in 20 unrelated blue crane individuals from South Africa, 14 loci were polymorphic, with each locus displaying between 2 and 7 alleles. Eight polymorphic loci were characterized in the grey-crowned crane (Balearica regulorum) and ten in the wattled crane (G. carunculatus).  相似文献   
63.
为研究繁殖丹顶鹤(Grus japonensis)弃卵原因,对其弃卵与正常卵壳超微结构及化学元素含量进行比较。以2014至2020年在扎龙保护区收集到丹顶鹤弃卵和正常孵化的卵各6枚为研究对象,利用电子扫描电镜观察比较其超微结构,采用电感偶合等离子体光谱仪测量其化学元素含量,并对其卵壳厚度和密度进行测量和比较。弃卵壳厚度、密度分别为正常卵壳厚度、密度的68.0%(P <0.01)和71.5%(P <0.01);弃卵卵壳表面晶体层厚度不均,与栅栏层之间界限不明显,外表皮层有龟裂和条形两种裂纹,栅栏锥体层晶体中有微小球状中空结构和类似溶洞的腔室结构,壳膜层纤维表面的片状突起较少,这些结构均与正常卵壳不同。检测卵壳23种化学元素中,弃卵卵壳Ca、Na、P、Mg和K元素含量显著低于正常孵卵卵壳(P <0.05)。从卵壳结构和元素分析,卵壳元素含量异常、结构和功能缺陷有可能是导致其亲鸟弃卵的原因之一,这与亲鸟占据生境资源情况、与其他鸟类间繁殖压力、食物可获得性和生存对策等交互作用的影响有关。  相似文献   
64.
小兴安岭白头鹤繁殖习性初报   总被引:9,自引:0,他引:9  
白头鹤(Grus monacha)仅繁殖于俄罗斯的远东地区和中国的小兴安岭森林沼泽湿地,越冬于日本南部、韩国南部沿海和中国长江中下游(Col-lar,2001),是国家一级保护野生动物,被中国濒危动物红皮书列为濒危物种,I UCN(1994,2001)列为易危(VU)物种,并列入CITES附录Ⅰ中(郑光美、王岐山  相似文献   
65.
小兴安岭白头鹤繁殖地种群数量初步调查   总被引:2,自引:0,他引:2  
2004年通过地面和航空调查等方法,对繁殖于小兴安岭沾河流域的白头鹤(Grusmonacha)种群进行了数量调查,共统计到白头鹤30只。发现了3对鹤的巢;2对以及2只单只的个体,虽然没有发现巢,但根据其保护领域的行为,可以确定其为繁殖个体。同时统计到13只没有参加繁殖的个体,以及3只不能判明是否参加繁殖的个体。通过本次调查表明,小兴安岭沾河流域的森林沼泽是我国白头鹤的重要繁殖地。  相似文献   
66.
笼养丹顶鹤的繁殖行为观察   总被引:3,自引:0,他引:3  
丹顶鹤(Grus japonensis)俗称“仙鹤”,其繁殖行为释放是一系列反射活动,笼养能引起丹顶鹤某些繁殖行为成分量的变化,但不能引起质的变化即并不会出现新的繁殖行为,在丹顶鹤的性行为程序中,行为成分常以固定动作方式有节律地反复演示,显示仪式化特征。  相似文献   
67.
Six subspecies of sandhill cranes (Gruscanadensis) have been denoted based onperceived morphological and/or breedinglocality differences among them. Threesubspecies are migratory, breeding from thehigh arctic in North America and Siberia(lesser sandhill, G. c. canadensis),south through central Canada (Canadiansandhill, G. c. rowani) and into thenorthern United States (greater sandhill, G. c. tabida). A review of sandhill cranetaxonomy indicates that the size variation, onthe basis of which these subspecies were named,may be clinal and not diagnostic. The otherthree subspecies, all listed as endangered orthreatened, are non-migratory, resident inFlorida (G. c. pratensis), Mississippi(G. c. pulla), and Cuba (G. c.nesiotes). We used analysis of mitochondrialDNA control region (CR) sequences to determinewhether haplotypes representing currentsubspecies show any genetic cohesion or aremore consistent with a pattern of clinalvariation in morphology. CR sequences indicatethat only two highly divergent (5.3%) lineagesof sandhill cranes occur in North America: onelineage composed only of arctic-nesting G.c. canadensis, the other of the remainingNorth American subspecies (we lack data on theCuban population). The deep split betweenlineages is consistent with an estimatedisolation of approximately 1.5 Mya(mid-Pleistocene), while the distribution ofmutational changes within lineages isconsistent with an hypothesis of rapid,post-Pleistocene population expansions. Noother phylogeographic structuring is concordantwith subspecific boundaries, however, analysisof molecular variance indicates that there issignificant population genetic differentiationamong all subspecies except G. c. tabidaand G. c. rowani, which areindistinguishable. We suggest thatrecognition of the recently named G. c.rowani be abandoned.  相似文献   
68.
向海湿地丹顶鹤迁徙动态及其栖息地保护研究   总被引:9,自引:0,他引:9  
基于1997~2003年间吉林省通榆县向海湿地春季丹顶鹤数量和分布数据,分析了丹顶鹤的迁徙动态及其与栖息地生态环境变化之间的关系.结果表明,1997~2003年间,每年春季丹顶鹤的种群数量分别为32、25、64、92、72、59和14只;丹顶鹤迁达向海的最早年份为2002年(3月12日),最晚年份为2001年(3月28日),大多年份于3月中旬到达向海;其产卵时间最早的年份为2000年(4月1日),最晚年份为2003年(5月10日),大多年份于4月上旬开始产卵;在分布上,以2000年丹顶鹤分布点最多(15个),1998年和2003年分布点较少(2个).表明丹顶鹤的迁徙动态随湿地水文条件的改变而变化.据此提出了利用洪水资源保护和恢复丹顶鹤等珍稀水禽栖息地的技术与对策.  相似文献   
69.
Artificial insemination has been used frequently in the captive whooping crane (Grus americana) population. In the 1980s, it was necessary at times to inseminate females with semen from several males during the breeding season or with semen from multiple males simultaneously due to unknown sperm viability of the breeding males. The goals of this study were to apply microsatellite DNA profiles to resolve uncertain paternities and to use these results to evaluate the current paternity assignment assumptions used by captive managers. Microsatellite DNA profiles were successful in resolving 20 of 23 paternity questions. When resolved paternities were coupled with data on insemination timing, substantial information was revealed on fertilization timing in captive whooping cranes. Delayed fertilization from inseminations 6+ days pre‐oviposition suggests capability of sperm storage. Zoo Biol 20:331–342, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
70.
半散放丹顶鹤越冬日活动行为   总被引:5,自引:1,他引:4  
2005年1月在盐城自然保护区和扎龙自然保护区观察半散放丹顶鹤(Grus japonensis)越冬行为,发现在迁徙丹顶鹤的越冬地盐城保护区,雌雄成体丹顶鹤多数日间行为(包括觅食、运动和修饰行为)无明显差异,而其行为与亚成体丹顶鹤存在一定差异。与盐城自然保护区相比,扎龙自然保护区的雄性、雌性及亚成体丹顶鹤日间的觅食、运动、修饰、静栖等行为均表现出显著差异,它们分别采用了相同或不同的行为对策来适应低温环境。  相似文献   
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