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世界珍稀水兽白豚(Lipotes vexillifer.)是我国名贵特产之一,属齿鲸亚目(Odontoceti),淡水豚总科(Platanistoidea),白鱀豚科(Lipotidae)。白鱀豚生活在长江中、下游。借回声定位系统以探知外界情况(荆显英等,1981)。通常认为,在声发射过程中,齿鲸类饱含油分的额隆组织起着声透镜的作用。额隆的这种特殊生理机能,与其所含脂质的脂肪酸组成密切相关。1980年陆佩洪等报道了白鱀豚额隆油的酸价、碘价、皂化价、不皂化物及甘油三酯(比色法)的含量。有关白鱀豚额隆油的脂肪酸组成,迄今尚未研究。目前我们才开始进行该项工作。 相似文献
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白鱀豚和江豚眼的测量 总被引:1,自引:0,他引:1
白鱀豚是我国特有的一种淡水豚,日前存在的数量已很少,因此是世界上一种珍贵而稀有的动物。同时,白鱀豚和江豚都是具有回声定位功能的动物,一般说,具有回声定位功能的动物其视觉都有不同程度的退化。为了了解白鱀豚的视觉功能,我们曾对其视神经和视网膜进行了研究。而眼的一些光学参数对视觉灵敏度的影响也是很大的。因此,本实验对白鱀豚 相似文献
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关于海豚和几种淡水豚类的血液学和血液生化指标国外有过研究4-13。白鱀豚(Lipotes vexillifer)血液有形成份已有过报道2,3。本实验对白鱀豚血液生化指标进行了研究,以期建立白鱀豚血液正常生理生化指标,为白鱀豚的临床诊断,健康监测和保健措施提供血液学参数,并且为完善淡水豚类血液学比较研究提供基础资料。
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白鱀豚饲养池水质状况的研究 总被引:5,自引:2,他引:3
白鱀豚是我国特有的稀珍水生哺乳动物。仅分布于长江的中、下游干流之中。关于如何饲养白鱀豚没有可借鉴的资料。在没有水净化装置和流水系统的条件下,为了既能节省人力和财力,又能保证豚体的健康,我们对白鱀豚饲养池的理化和微生物因子进行了系统、全面的测定和研究。
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Evolution of river dolphins 总被引:6,自引:0,他引:6
Hamilton H Caballero S Collins AG Brownell RL 《Proceedings. Biological sciences / The Royal Society》2001,268(1466):549-556
The world's river dolphins (Inia, Pontoporia, Lipotes and Platanista) are among the least known and most endangered of all cetaceans. The four extant genera inhabit geographically disjunct river systems and exhibit highly modified morphologies, leading many cetologists to regard river dolphins as an unnatural group. Numerous arrangements have been proposed for their phylogenetic relationships to one another and to other odontocete cetaceans. These alternative views strongly affect the biogeographical and evolutionary implications raised by the important, although limited, fossil record of river dolphins. We present a hypothesis of river dolphin relationships based on phylogenetic analysis of three mitochondrial genes for 29 cetacean species, concluding that the four genera represent three separate, ancient branches in odontocete evolution. Our molecular phylogeny corresponds well with the first fossil appearances of the primary lineages of modern odontocetes. Integrating relevant events in Tertiary palaeoceanography, we develop a scenario for river dolphin evolution during the globally high sea levels of the Middle Miocene. We suggest that ancestors of the four extant river dolphin lineages colonized the shallow epicontintental seas that inundated the Amazon, Paraná, Yangtze and Indo-Gangetic river basins, subsequently remaining in these extensive waterways during their transition to freshwater with the Late Neogene trend of sea-level lowering. 相似文献
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Martínez-Agüero M Flores-Ramírez S Ruiz-García M 《Genetics and molecular research : GMR》2006,5(3):421-431
We report the first major histocompatibility complex (MHC) DQB1 sequences for the two species of pink river dolphins (Inia geoffrensis and Inia boliviensis) inhabiting the Amazon and Orinoco River basins. These sequences were found to be polymorphic within the Inia genus and showed shared homology with cetacean DQB-1 sequences, especially, those of the Monodontidae and Phocoenidae. On the other hand, these sequences were shown to be divergent from those described for other riverine dolphin species, such as Lipotes vexillifer, the Chinese river dolphin. Two main conclusions can be drawn from our results: 1) the Mhc DQB1 sequences seem to evolve more rapidly than other nuclear sequences in cetaceans, and 2) differential positive selective pressures acting on these genes cause concomitant divergent evolutionary histories that derive phylogenetic reconstructions that could be inconsistent with widely accepted intertaxa evolutionary relationships elucidated with other molecular markers subjected to a neutral dynamics. 相似文献
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DISTRIBUTION AND ABUNDANCE OF THE AMAZON RIVER DOLPHIN (INIA GEOFFRENSIS) AND THE TUCUXI (SOTALIA FLUVIATILIS) IN THE UPPER AMAZON RIVER 总被引:1,自引:0,他引:1
Omar Vidal Jay Barlow Luis A. Hurtado Jorge Torre Patricia Cendón Zully Ojeda 《Marine Mammal Science》1997,13(3):427-445
A boat survey was conducted from 5 to 26 June 1993 to estimate the abundance of the Amazon river dolphin ( Inia geoffrensis ) and the tucuxi ( Sotalia fluviatilis ) along ca . 120 km of the Amazon River bordering Colombia, Peru, and Brazil. Two survey methods were used: line transects during 5 d and strip transects during 15 d. The line transects were used to estimate the abundance of both species in the main channels of the Amazon at distances greater than 200 m from river banks and islands, and strip transects were used to estimate abundance in the remainder of the habitat. A total of 29 sightings was obtained using line transects, including 8 of Inia , 15 of Sotalia , and 6 with both species present. The total number of sightings made while using strip transects was 143, including 78 of Inia , 51 of Sotalia , and 14 with both species present. The distributions of sightings with respect to distance from the nearest bank were not significantly different between the two species. Based on the results from the two methods, we estimate that there are 346 (CV = 0.12) Inia and 409 (CV = 0.13) Sotalia in the study area. Overall, the mean group size for Inia was 2.9 individuals and for Sotalia was 3.9 individuals. Inia density (dolphin/km2 ) was highest in tributaries (4.8), followed by areas around islands (2.7) and along main banks (2.0); while Sotalia density was highest in lakes (8.6), followed by areas along main banks (2.8) and around islands (2.0). These are among the highest densities measured to date for any cetacean. 相似文献
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MOLECULAR SYSTEMATICS OF RIVER DOLPHINS INFERRED FROM COMPLETE MITOCHONDRIAL CYTOCHROME-B GENE SEQUENCES 总被引:6,自引:0,他引:6
Guang Yang Kaiya Zhou Wenhua Ren Guoqing Ji Shan Liu Richardo Bastida Laura Rivero 《Marine Mammal Science》2002,18(1):20-29
1,140 bp of the complete mitochondrial cytochrome- b gene sequences of baiji ( Lipotes vexillifer ), franciscana ( Pontoporia blainvillei ), and Ganges river dolphin ( Platanista gangetica gangetica ) were determined to address the systematic position and phylogeny of extant river dolphins with combination of homologous sequences of other cetaceans. The neighbor-joining (NJ), maximum parsimony (MP), and maximum likelihood (ML) phylogenetic analyses all identified the river dolphins into three lineages, i. e., Platanista, Lipotes , and Inia + Pontoporia . The Lipotes did not have sister relationship with either Platanista or Inia + Pontoporia , which strongly supported the referral of Lipotes to a separate family, i. e. , Lipotidae. There were very high sequence divergences between all river dolphin genera, suggesting a relatively longer period of separation time than those among other odontocete families. 相似文献
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We developed polymerase chain reaction primers for 12 dinucleotide microsatellite loci in the bottlenose dolphin, Tursiops truncatus. Seven markers were obtained after hybridization screening, and five following random genome sequencing. Orthologous positions were computed for nine markers on the bovine genome and for seven on the human genome. The markers are distributed across chromosomes and found in different types of DNA regions. All 12 loci are polymorphic for Tursiops. Five loci were also polymorphic in the related species Stenella frontalis and the more distantly related river dolphin, Inia geoffrensis, indicating these markers will be informative across the Delphinidae and other cetacean taxa. 相似文献
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Mark T. Bowler Brian M. Griffiths Michael P. Gilmore Andrew Wingfield Maribel Recharte 《Acta ethologica》2018,21(2):141-145
Infanticide by males is a phenomenon common in species in which the reproductive output of large numbers of females can be monopolized by a small number of males. It is thought to increase a male’s fitness, at the expense of the fitness of the infant’s parents, by bringing females into season more quickly. Infanticide by males has been recorded in just three cetacean species. We report aggressive behavior suggestive of infanticide in a fourth, the Amazon river dolphin (Inia geoffrensis). We observed and photographed a series of attacks on a neonate Amazon river dolphin by a large male, with apparent protective behavior by the mother. Although infanticide was not confirmed, the forceful, aggressive behaviors were highly suggestive of infanticidal behavior and represent another important data point for comparative studies of infanticide in mammals. Amazon river dolphins may have a polygynous, polyandrous, or promiscuous mating system, the latter two of which are not the norm in species in which the reproductive output of large numbers of females are monopolized by a small number of males. However, sexual dimorphism, high rates of aggression by males, socio-sexual object-carrying displays by males, and a long interbirth interval suggest that successful male Amazon river dolphins may be able to monopolize a large proportion of mating opportunities, and it is plausible that male dolphins can improve their reproductive success by bringing females into estrous sooner by killing the offspring of other males. 相似文献
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Banguera-Hinestroza E Cárdenas H Ruiz-García M Marmontel M Gaitán E Vázquez R García-Vallejo F 《The Journal of heredity》2002,93(5):312-322
The Amazon river dolphin, genus Inia, is endemic to the major river basins of northern South America. No previous studies have focused on the genetic structure of this genus. In this work, 96 DNA samples from specimens of this genus were collected in the Orinoco basin (four rivers), the Putumayo River, a tributary of the Colombian Amazon and the Mamoré, and the Tijamuchí and Ipurupuru rivers in theBolivian Amazon. These samples were used to amplify a fragment of 400 bp of the mitochondrial DNA (mtDNA) control region. In addition, 38 of these samples were also used to sequence 600 bp of the mitochondrial cytochrome b gene. The analysis of the population structure subdivision with an analysis of molecular variance (AMOVA) revealed important aspects about the genetic structure of Inia groups fromthese three geographically separate regions. By comparing the control region DNA and cytochrome b sequences, distinct types of nonshared haplotypes were observed. The net genetic divergence of control region sequences was 6.53% between the Orinoco and Bolivian rivers, 5.32% between the Putumayo and Bolivian rivers, and 2.50% between the Orinoco and Putumayo rivers. For the cytochrome b gene, these values were 2.48%, 2.98%, and 0.06%, respectively. The nucleotide sequences were analyzed phylogenetically using several genetic distance matrices and applying neighbor-joining, maximum likelihood, and maximum parsimony procedures. The results support the proposal to subdivide the Inia genus into at least two evolutionarily significant units: one confined to the Bolivian river basin and the other widely distributed across the Amazon and Orinoco basins. 相似文献
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Catalina Gomez‐Salazar Fernando Trujillo Marcela Portocarrero‐Aya Hal Whitehead 《Marine Mammal Science》2012,28(1):124-153
This study is part of an on‐going effort to evaluate and monitor river dolphin populations in South America. It comprises the largest initiative to estimate population size and densities of Inia and Sotalia dolphins using statistically robust and standardized methods. From May 2006 to August 2007, seven visual surveys were conducted in selected large rivers of Bolivia, Colombia, Brazil, Ecuador, Peru, and Venezuela in the Amazon and Orinoco river basins. Population sizes of Inia and Sotalia were estimated for different habitats (main river, tributary, lake, island, confluence, and channel). A total of 291 line and 890 strip transects were conducted, covering a distance of 2,704 linear kilometers. We observed 778 Inia geoffrensis, 1,323 Inia boliviensis, and 764 Sotalia fluviatilis. High‐density areas were identified (within 200 m from the river banks, confluences, and lakes) and we propose that these constitute critical habitat for river dolphins. High densities of river dolphins seem to coincide with well‐managed freshwater protected areas and should be considered as hot spots for river dolphins in South America. 相似文献
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Gravena W Hrbek T DA Silva VM Astolfi-Filho S Farias IP 《Molecular ecology resources》2009,9(2):600-603
We developed specific primers for microsatellite DNA regions for the Amazon River dolphin or boto Inia geoffrensis, for use in population and conservation genetic studies. We also tested their transferability for two other species, Pontoporia blainvillei (sister taxon of I. geoffrensis) and Sotalia guianensis. A total of 12 microsatellite loci were polymorphic for the boto. An additional 25 microsatellite loci previously isolated from other cetacean species were also tested in the boto. The 26 polymorphic microsatellite loci indicate they will be excellent markers for studies of population structure and kinship relations of the boto. 相似文献