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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Resolution of Phylogenetic Relationships and Characterization of Y-Linked Microsatellites within the Big Cats, Panthera

Davis, Brian W. 2009 August 1900 (has links)
The pantherine lineage of cats diverged from the remainder of modern Felidae less than 11 million years ago. This clade consists of the five big cats of the genus Panthera, the lion, tiger, jaguar, leopard, and snow leopard, as well as the closely related clouded leopard, which diverged from Panthera approximately 6 million years ago. A significant problem exists with respect to the precise phylogeny of these highly threatened great cats. Within the past four years, despite multiple publications on the subject, no two studies have reconstructed the phylogeny of Panthera with the same topology, showing particular discordance with respect to sister-taxa relationships to the lion and the position of the enigmatic snow leopard. The evolutionary relationship among these cats remains unresolved partially due to their recent and rapid radiation 3-5 million years ago, individual speciation events occurring within less than 1 million years, and probable introgression between lineages following their divergence. We assembled a 47.6 kb dataset using novel and published DNA sequence data from the autosomes, both sex chromosomes and the mitochondrial genome. This dataset was analyzed both as a supermatrix and with respect to individual partitions using maximum likelihood and Bayesian phylogeny inference. Since discord may exist among gene segments in a multilocus dataset due to their unique evolutionary histories, inference was also performed using Bayesian estimation of species trees (BEST) to form a robust consensus topology. Incongruent topologies for autosomal loci indicated phylogenetic signal conflict within the corresponding segments. We resequenced four mitochondrial and three nuclear gene segments used in recent attempts to reconstruct felid phylogeny. The newly generated data was combined with available GenBank sequence data from all published studies to highlight phylogenetic disparities stemming either from the amplification of a mitochondrial to nuclear translocation event, or errors in species identification. We provide an alternative, highly supported interpretation of the evolutionary history of the pantherine lineage using 39 single-copy regions of the felid Y chromosome and supportive phylogenetic evidence from a revised mitochondrial partition. These efforts result in a highly corroborated set of species relationships that open up new avenues for the study of speciation genomics and understanding the historical events surrounding the origin of the members of this lineage.
42

The sustainability of leopard panthera pardus sport hunting in Niassa Reserve, Mozambique.

Jorge, Agostinho A. January 2012 (has links)
Leopard Panthera pardus are an economically valuable asset and when used in sustainable consumptive use programs can provide tangible benefits to communities to improve human livelihoods and the conservation of the species. Sport hunting is increasingly proposed as a tool to generate funds to support the conservation of leopard and other large carnivores. However, to assess the value of sport hunting as a conservation tool it is critical to understand its economic impact and ensure that the off-takes are sustainable. In this study I assessed the conservation status of leopard and the ecological sustainability of legal and illegal off-take in Niassa National Reserve (NNR) the largest protected area, 42,000 km2, in Mozambique, which is inhabited by 35,000 people. I also investigated whether the revenues from leopard sport hunting off-set the costs of depredation on livestock in local communities and individual benefits from poaching by local hunters. To perform this study, I interviewed hunting operators and villagers, collected camera trapping data, and analyzed long-term leopard sport hunting data. Leopard had high value for sport hunters, however, the economic benefits from the legal hunting did not off-set the costs from livestock depredation and did not compete with benefits from the illegal hunting which accrued to individuals at the household level. Leopard population densities in Niassa Reserve were comparable with the study sites in central and southern Africa. The numbers of leopard legally hunted in NNR appear to be ecologically sustainable, however a high percentage of the leopard taken as trophies were under the recommended age of seven years. The illegal off-take was unsustainable and resulting in high turnover and combined with the operators’ off-take is likely to be negatively affecting leopard populations. For the future ecological and economic sustainability of leopard quotas, I recommend improvements in the distribution of economic benefits and creating economic incentives to encourage villagers not to engage in the illegal hunting and quantification and inclusion of the illegal off-take in the annual quotas. My study also indicates the need to zone community and wildlife areas in NNR to reduce the anthropogenic effects on leopard and other carnivore populations. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2012.
43

Efeitos de barragem de hidrelétrica sobre áreas de uso e adequabilidade de habitat de onças-pintadas (Panthera onca) (Carnivora: Felidae) nas várzeas do Alto Rio Paraná, Mata Atlântica

Sana, Denis Alessio January 2013 (has links)
Praticamente todos os ecossistemas naturais têm sido afetados pelas atividades humanas. A construção de usinas hidrelétricas produz grandes impactos ambientais causando problemas notáveis como a fragmentação e perdas de habitats. No Brasil aproximadamente 70% da matriz energética é formada por hidrelétricas e há previsão de expansão nos próximos anos. A degradação ambiental é apontada como a principal ameaça à conservação da biodiversidade e a maior causa do declínio das populações de espécies ameaçadas, especialmente de grandes mamíferos e, particularmente, de grandes carnívoros. Apesar da ampla distribuição no continente, as populações de onça-pintada (Panthera onca) têm sido reduzidas ou extintas pela pressão antrópica, tendo sua área de distribuição reduzida aproximadamente à metade. No Brasil é considerada uma espécie Vulnerável e está Criticamente Ameaçada de extinção na Mata Atlântica. Na Ecorregião Florestas do Alto Paraná está distribuída na forma de metapopulação, possivelmente em processo de isolamento de suas subpopulações. No Alto Rio Paraná a Usina Hidrelétrica de Porto Primavera (UHEPP) alagou em 1998 uma área de cerca de 2.250 km². A dissertação aborda este impacto ambiental e tem por objetivo avaliar como o enchimento do reservatório da UHEPP afetou a população de onças-pintadas na região, em relação à distribuição espacial e adequabilidade de habitat. Foram monitorados 11 indivíduos por radiotelemetria em dois períodos (1992 a 1995 e 1998 a 2002), investigando-se o tamanho de área de uso e movimentação. Com estes dados mais a cobertura de solo foram avaliadas adequabilidade ambiental e seleção de habitat. A distribuição espacial e a adequabilidade do habitat foram avaliadas em dois cenários, anterior e posterior ao enchimento, relacionando as mudanças ocorridas com o impacto na área sob o efeito direto do enchimento. Um terceiro cenário foi também avaliado, englobando toda a área de várzea remanescente no Alto Rio Paraná e incluindo as Unidades de Conservação (UCs), quanto à adequabilidade e seleção de habitat. Para este cenário foram utilizadas localizações de outros 10 indivíduos monitorados no Parque Estadual das Várzeas do Rio Ivinhema, Mato Grosso do Sul e no Parque Estadual Morro do Diabo, São Paulo, entre 1998 e 2005. Após o enchimento houve um aumento significativo nas dimensões das áreas de uso das onças-pintadas (fêmeas: anterior, 78 km² [n=8]; posterior, 197 km² [n=5]; macho [n=1]: anterior, 111 km²; posterior, 149 km²) bem como em seus deslocamentos máximos, pois passaram a ocupar áreas mais degradadas de fazendas, com poucos refúgios e presas naturais. Porém não foram observadas diferenças nos deslocamentos médios e sobreposição de áreas, assim como as áreas de uso não diferiram sazonalmente. A modelagem de habitat demonstrou que o enchimento atingiu principalmente as áreas mais favoráveis para a espécie suprimindo cerca de metade dessas. As onças selecionaram várzeas e florestas enquanto que a paisagem altamente modificada pelo homem foi evitada. Com as áreas mais degradadas ocupadas e o conflito com o homem, grande parte dos animais foram mortos em retaliação à predação de animais domésticos, levando praticamente a extinção local da espécie na área sob o efeito direto do enchimento. A área remanescente do Alto Rio Paraná comporta ainda cerca de 50 onças-pintadas adultas, sendo um terço em UCs. Portanto áreas adjacentes às UCs, na sua maioria com várzeas, devem ser preservadas e áreas florestais devem ser restauradas para a conservação da espécie em longo prazo na região. As informações geradas nesta dissertação podem auxiliar nas ações de conservação e manejo da onça-pintada no Alto Rio Paraná e mostra que a modelagem de habitat pode ser uma importante ferramenta para avaliação de impactos ambientais. / Virtually all natural ecosystems have been affected by human activities. The construction of hydroelectric power plants is the cause of major environmental impacts, such as habitat destruction and fragmentation. Brazil's energy matrix is mostly based on hydroelectricity, which comprises approximately 70% of all produced energy in the country, and the national government plans to expand it in the coming years. Habitat destruction is considered the main threat to biodiversity conservation and the major cause of the decline of endangered species, especially large mammals and large carnivores. Despite their wide distribution in the Americas, jaguar (Panthera onca) populations have been reduced or extinguished by human pressure, and the species current distribution represents half of its past distribution. In Brazil, the jaguar is considered a vulnerable species and it is critically endangered in the Atlantic Rain Forest. In the Upper Paraná Forest Ecoregion the species is distributed as a metapopulation, possibly in an isolation process of its subpopulations. In the Upper Paraná River (UPR), the reservoir filling of the Porto Primavera Hydroelectric plant (PPHE) began in 1998, and flooded an area of approximately 2250 km ². I evaluated the effects of the PPHE reservoir filling on the local jaguar population, its effects on the species spatial distribution and habitat suitability. I monitored a total of 11 jaguars using radio telemetry in two periods (1992-1995 and 1998-2002). I investigated jaguar home range size and movements, and evaluated habitat selection and suitability combing spatial and land cover data (Geographic Information System). These two metrics were measured before and after reservoir filling, linking the impact with changes in the species spatial patterns between these two phases. I evaluated three scenarios: the area affected directly by the PPHE filling, before and after, and all the remaining wetlands in the UPR, including protected areas. Jaguars’ home ranges increased significantly after reservoir filling (females: 78 km ² before [n = 8], 197 km ² after [n = 5]; male [n = 1]: 111 km ² before, 149 km ² after). Maximum movement of the four jaguars (3 females and 1 male) also increased from one phase to the other (10.75 km before; 25.05 km after). The increase in movement patterns results from jaguars using new and more degraded areas in farms, where there are few refuges and natural preys. Home ranges did not differ seasonally on the first period; neither did the mean movements and overlapping areas. The PPHE filling mainly affected jaguars by suppressing approximately half of their suitable area. Jaguars selected wetlands and forests and avoided landscapes heavily modified by Man. Most jaguars were killed in retaliation to cattle predation as they commenced to occupy the most degraded areas, nearly driving the population to extinction. The remaining area of the UPR still holds approximately 50 adult jaguars and one third of them are in protected areas. Therefore, the long-term species conservation depends on the preservation of the adjacent wetlands and on the restoration of forest patches. My results can subsidize jaguar conservation and management plans in the UPR and show that habitat suitability modeling can be a useful tool for assessing environmental impacts.
44

Efeitos de barragem de hidrelétrica sobre áreas de uso e adequabilidade de habitat de onças-pintadas (Panthera onca) (Carnivora: Felidae) nas várzeas do Alto Rio Paraná, Mata Atlântica

Sana, Denis Alessio January 2013 (has links)
Praticamente todos os ecossistemas naturais têm sido afetados pelas atividades humanas. A construção de usinas hidrelétricas produz grandes impactos ambientais causando problemas notáveis como a fragmentação e perdas de habitats. No Brasil aproximadamente 70% da matriz energética é formada por hidrelétricas e há previsão de expansão nos próximos anos. A degradação ambiental é apontada como a principal ameaça à conservação da biodiversidade e a maior causa do declínio das populações de espécies ameaçadas, especialmente de grandes mamíferos e, particularmente, de grandes carnívoros. Apesar da ampla distribuição no continente, as populações de onça-pintada (Panthera onca) têm sido reduzidas ou extintas pela pressão antrópica, tendo sua área de distribuição reduzida aproximadamente à metade. No Brasil é considerada uma espécie Vulnerável e está Criticamente Ameaçada de extinção na Mata Atlântica. Na Ecorregião Florestas do Alto Paraná está distribuída na forma de metapopulação, possivelmente em processo de isolamento de suas subpopulações. No Alto Rio Paraná a Usina Hidrelétrica de Porto Primavera (UHEPP) alagou em 1998 uma área de cerca de 2.250 km². A dissertação aborda este impacto ambiental e tem por objetivo avaliar como o enchimento do reservatório da UHEPP afetou a população de onças-pintadas na região, em relação à distribuição espacial e adequabilidade de habitat. Foram monitorados 11 indivíduos por radiotelemetria em dois períodos (1992 a 1995 e 1998 a 2002), investigando-se o tamanho de área de uso e movimentação. Com estes dados mais a cobertura de solo foram avaliadas adequabilidade ambiental e seleção de habitat. A distribuição espacial e a adequabilidade do habitat foram avaliadas em dois cenários, anterior e posterior ao enchimento, relacionando as mudanças ocorridas com o impacto na área sob o efeito direto do enchimento. Um terceiro cenário foi também avaliado, englobando toda a área de várzea remanescente no Alto Rio Paraná e incluindo as Unidades de Conservação (UCs), quanto à adequabilidade e seleção de habitat. Para este cenário foram utilizadas localizações de outros 10 indivíduos monitorados no Parque Estadual das Várzeas do Rio Ivinhema, Mato Grosso do Sul e no Parque Estadual Morro do Diabo, São Paulo, entre 1998 e 2005. Após o enchimento houve um aumento significativo nas dimensões das áreas de uso das onças-pintadas (fêmeas: anterior, 78 km² [n=8]; posterior, 197 km² [n=5]; macho [n=1]: anterior, 111 km²; posterior, 149 km²) bem como em seus deslocamentos máximos, pois passaram a ocupar áreas mais degradadas de fazendas, com poucos refúgios e presas naturais. Porém não foram observadas diferenças nos deslocamentos médios e sobreposição de áreas, assim como as áreas de uso não diferiram sazonalmente. A modelagem de habitat demonstrou que o enchimento atingiu principalmente as áreas mais favoráveis para a espécie suprimindo cerca de metade dessas. As onças selecionaram várzeas e florestas enquanto que a paisagem altamente modificada pelo homem foi evitada. Com as áreas mais degradadas ocupadas e o conflito com o homem, grande parte dos animais foram mortos em retaliação à predação de animais domésticos, levando praticamente a extinção local da espécie na área sob o efeito direto do enchimento. A área remanescente do Alto Rio Paraná comporta ainda cerca de 50 onças-pintadas adultas, sendo um terço em UCs. Portanto áreas adjacentes às UCs, na sua maioria com várzeas, devem ser preservadas e áreas florestais devem ser restauradas para a conservação da espécie em longo prazo na região. As informações geradas nesta dissertação podem auxiliar nas ações de conservação e manejo da onça-pintada no Alto Rio Paraná e mostra que a modelagem de habitat pode ser uma importante ferramenta para avaliação de impactos ambientais. / Virtually all natural ecosystems have been affected by human activities. The construction of hydroelectric power plants is the cause of major environmental impacts, such as habitat destruction and fragmentation. Brazil's energy matrix is mostly based on hydroelectricity, which comprises approximately 70% of all produced energy in the country, and the national government plans to expand it in the coming years. Habitat destruction is considered the main threat to biodiversity conservation and the major cause of the decline of endangered species, especially large mammals and large carnivores. Despite their wide distribution in the Americas, jaguar (Panthera onca) populations have been reduced or extinguished by human pressure, and the species current distribution represents half of its past distribution. In Brazil, the jaguar is considered a vulnerable species and it is critically endangered in the Atlantic Rain Forest. In the Upper Paraná Forest Ecoregion the species is distributed as a metapopulation, possibly in an isolation process of its subpopulations. In the Upper Paraná River (UPR), the reservoir filling of the Porto Primavera Hydroelectric plant (PPHE) began in 1998, and flooded an area of approximately 2250 km ². I evaluated the effects of the PPHE reservoir filling on the local jaguar population, its effects on the species spatial distribution and habitat suitability. I monitored a total of 11 jaguars using radio telemetry in two periods (1992-1995 and 1998-2002). I investigated jaguar home range size and movements, and evaluated habitat selection and suitability combing spatial and land cover data (Geographic Information System). These two metrics were measured before and after reservoir filling, linking the impact with changes in the species spatial patterns between these two phases. I evaluated three scenarios: the area affected directly by the PPHE filling, before and after, and all the remaining wetlands in the UPR, including protected areas. Jaguars’ home ranges increased significantly after reservoir filling (females: 78 km ² before [n = 8], 197 km ² after [n = 5]; male [n = 1]: 111 km ² before, 149 km ² after). Maximum movement of the four jaguars (3 females and 1 male) also increased from one phase to the other (10.75 km before; 25.05 km after). The increase in movement patterns results from jaguars using new and more degraded areas in farms, where there are few refuges and natural preys. Home ranges did not differ seasonally on the first period; neither did the mean movements and overlapping areas. The PPHE filling mainly affected jaguars by suppressing approximately half of their suitable area. Jaguars selected wetlands and forests and avoided landscapes heavily modified by Man. Most jaguars were killed in retaliation to cattle predation as they commenced to occupy the most degraded areas, nearly driving the population to extinction. The remaining area of the UPR still holds approximately 50 adult jaguars and one third of them are in protected areas. Therefore, the long-term species conservation depends on the preservation of the adjacent wetlands and on the restoration of forest patches. My results can subsidize jaguar conservation and management plans in the UPR and show that habitat suitability modeling can be a useful tool for assessing environmental impacts.
45

Importância das interações bióticas na distribuição geográfica das espécies e suas aplicações em modelos de distribuição potencial

Santos, Thiago 14 June 2013 (has links)
Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-12-08T17:37:44Z No. of bitstreams: 1 Tese-Thiago Santos-2013.pdf: 3081181 bytes, checksum: 2458be035ed935ff9e529ed2df6f9200 (MD5) / Rejected by Jaqueline Silva (jtas29@gmail.com), reason: on 2014-12-08T19:42:18Z (GMT) / Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-12-12T19:32:30Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese-Thiago Santos-2013.pdf: 3081181 bytes, checksum: 2458be035ed935ff9e529ed2df6f9200 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-12-16T09:22:12Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese-Thiago Santos-2013.pdf: 3081181 bytes, checksum: 2458be035ed935ff9e529ed2df6f9200 (MD5) / Made available in DSpace on 2014-12-16T09:22:13Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese-Thiago Santos-2013.pdf: 3081181 bytes, checksum: 2458be035ed935ff9e529ed2df6f9200 (MD5) Previous issue date: 2013-06-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / (Sem resumo em outra língua) / Dentre os mecanismos que geram as distribuições das espécies, tem sido atribuído um papel localàs interações biológicasenquanto que as causas de padrões regionais ou globais são atribuídas às variáveis abióticas.Recentemente,um número crescente de trabalhostem concluído que as interações biológicas interespecíficas apresentam efeitos significativos sobre os limites das distribuições das espécies e que a variação espacial em grande escala de atributos populacionais, como a densidade, é mais bem explicada pelas interações que pelas condições abióticas. Os objetivos deste trabalho são, portanto, mensurar a importância das interações biológicas na distribuição espacial das espécies, tanto em relação aos limites das distribuições quanto à variação espacial nas densidades populacionais e discutir novas técnicas para se incluir as interações interespecíficas nos modelos de distribuição potencial. No primeiro capítulo, um modelo estatístico de sistema de equações foi empregado para se verificar o efeito da competição entre duas espécies de cupins de montículos, Cornitermescumulans e Cornitermes silvestrii.No segundo capítulo, foi analisado o efeito da distribuição potencial de Crotalaria maypurensis (Fabaceae), sobre a distribuição potencial de Utetheisa ornatrix(Arctiidae). No terceiro capítulo, a distribuição de um predador de topo, Panthera onca, e a variação espacial de sua densidade populacional foram estimadas usando-se modelos alométricos de interação predador-presa.
46

Morphology of the female reproductive organs of the African lion (Panthera leo)

Hartman, Marthinus Jacobus January 2012 (has links)
The objectivie of this study was to describe the splanchnology and topography of the female reproductive organs of the African lion. The reproductive organs of three embalmed cadavers from three-year-old known aged nulliparous lionesses weighing between 120 kg and 140 kg were studied. Two fresh carcasses from another study were used for some of the topographical photos since these rendered better quality images. The project was approved by the Animal Use and Care Committee and Research Committee of the University of Pretoria (protocol number V038-09). The topography and splanchnology of the reproductive organs were studied and described in situ and after removal. The kidneys were located far caudally in relation to the thirteenth ribs with the left kidney further caudal. The suspensory ligament was very well developed. It originated in a fan-like manner from the dorso-lateral abdominal wall lateral to the kidney extending up to a few centimetres cranial to the kidney. The proper ligament of the ovary was well developed and consisted of several clearly distinguishable bands. The broad ligament resembled that of the cat with the exeption of the cranial part of the mesovarium being very well developed. The round ligament was well developed and inserted on the medial femoral fascia. It therefore did not extend to the vulva as in other canine and feline species. The left ovary was longer, wider and heavier than its right counterpart and the ovaries were relatively small in relation to body weight. The ovarian bursa had a short mesosalpinx that did not cover any part of the ovary and the fimbriae extended the entire length of the ovary. The urethral tuberculum as well as the urethral crest was very well developed. The left uterine horn was longer than the right and the tip of the uterine horn was located dorsal to the proper ligament. The uterine tube was prominently convoluted, situated entirely on the lateral aspect of the ovary and was found to open directly into the tip of the uterine horn and not onto a papilla. The female reproductive organs of the African lion resemble that of the domestic cat and dog with some major differences especially to the size and development of certain structures. The clinical relevance of these differences has to be debated and some thoughts might include the following: 1) does the suspensory and proper ligaments of the gravid uterus contract to suspend the entire uterus closer to the body wall during hunting since the lioness is the primary hunter in the pride? 2) does the lioness have to roll on her back and extend her back legs after mating to facilitate sperm entering the dorsally located tip of the uterine horn while the round ligament stabilises the terminal part of the uterine horn, and does this have a bearing on the fact that multiple copulations are required over a prolonged period for conception by lions? 3) do more ovulations take place from the bigger left ovary and? 4) are more conceptusses borne by the longer left uterine horn? The anatomical information obtained during this study was subsequently applied in a surgical study on sixteen lionesses using laparoscopy to perform laparoscopic ovariectomy and salpingectomy. The availability of these two laparoscopic procedures subsequently led to a wider interest to its application in population control of lions in the smaller national parks of South Africa. / Dissertation (MMedVet)--University of Pretoria, 2012. / gm2014 / Companion Animal Clinical Studies / unrestricted
47

Krankheiten, Fortpflanzung und Immobilisation der Tiger (Panthera tigris) im Zoologischen Garten Leipzig unter besonderer Berücksichtigung der "Tigerkrankheit"

Vollrath, Constance 10 November 2009 (has links)
Veterinärmedizinische Fakultät, Universität Leipzig, und Zoo Leipzig Die Krankheiten, Fortpflanzung und Immobilisation der Tiger des für seine Zucht berühmten Leipziger Zoologischen Gartens wurden zusammenfassend über einen Zeitraum von über 50 Jahren analysiert. Das Datenmaterial bestand aus Kranken- und Sektionsberichten sowie bakteriologischen, virologischen, parasitologischen und mykologischen Untersuchungsbefunden. Insgesamt wurden über 4000 Fälle ausgewertet und mit der medizinischen Fachliteratur verglichen. Die Ergebnisse der vorliegenden Arbeit zeigen, dass sich die Haltungsbedingungen der Tiger im Leipziger Zoologischen Garten im Laufe der Zeit wesentlich verbessert haben und der Gesundheitsstatus heute als sehr gut eingeschätzt werden kann. Zur Distanzimmobilisation und -narkose haben sich die Kombination von 3 mg/kg Xylazin und 3 mg/kg KM Ketaminhydrochlorid sowie Yohimbin als Antidot in einer Dosis von 0,5 mg/kg KM bewährt. Zu den häufigsten Krankheitsbildern gehörten Infektionskrankheiten, unter ihnen die sog. Koliinfektion und die Pasteurellose. Obwohl sie heute mit einfachen Mitteln therapierbar sind, verursachten sie seinerzeit in der Studienpopulation gleichzeitig v. a bei Jungtigern große Verluste. Seit Beginn der BCG-Impfung ist die Tuberkulose nicht mehr im Leipziger Tigerbestand aufgetreten. Ebenso brachte die Umstellung auf eine Lebendvakzine bei der Panleukopenieprophylaxe eine entscheidende Verbesserung. Die meisten Todesfälle verursachten nach den Infektionskrankheiten Krankheiten des Respirationstrakts (Pneumonien) und Fortpflanzungsstörungen (v. a. Totgeburten). Ab einem Alter von 9 Jahren traten bei weiblichen Tigern Störungen im Geburtsverlauf auf. Am häufigsten erkrankten neonatale Tiger an Infektionskrankheiten und an den Folgen von Fruchtwasseraspiration. Bei den Krankheiten des Bewegungsapparats steht die auf einem alimentären sekundären Hyperparathyreoidismus beruhende Osteodystrophia fibrosa im Vordergrund. Ihr wird seit den 80er Jahren durch verstärkte Fütterung mit Ganzkörperfuttertieren vorgebeugt. Als Therapie von Nephritiden hat sich bei den Tigern des Untersuchungsguts besonders in den letzten Jahren eine einmalige subkutane Infusionstherapie mit insgesamt 2 ml/kg KM Glukose und Natriumbikarbonat im Verhältnis 1:1 sowie Elektrolyten und Aminosäuren, Enrofloxacin und Marbofloxacin in den von den Herstellern angegebenen Dosierungen bewährt. Regelmäßige Krallenpflege ab einem Alter von 9 Jahren beugt Lahmheiten durch eingewachsene Krallen sowie Wundinfektionen vor. Vitaminmängeln wird im Leipziger Zoologischen Garten durch Fütterung von Ganzkörpertieren mit allen Innereien sowie die prophylaktische Gabe von Multivitaminpräparaten vorgebeugt. Möglicherweise verhaltensbedingte Todesfälle bei ansonsten gesunden neonatalen Tigern lassen in einigen Fällen auf eine gestörte Mutter-Kind-Beziehung schließen. Lediglich vereinzelt traten im Untersuchungsgut Krankheiten der Leber, des Herz- und Kreislaufsystems, des endokrinen Systems, Vergiftungen, sexuelle Verhaltensstörungen und Kachexien auf. Bestandsprobleme wurden durch Caliciviren hervorgerufen, die klinische Symptome sowohl bei adulten als auch jungen Tigern und Löwen hervorriefen. Hier muss zwischen artgemäßer Aufzucht und Infektionsrisiko abgewogen werden. Zu den erst postmortal festgestellten Krankheiten gehörte das metastasierende Hämangiosarkom. Die „Tigerkrankheit“ gehörte über viele Jahre zu den schwer behandelbaren Krankheiten mit hoher Rezidivrate. Mittlerweile haben sich zwar Ampicillin und Penicillin als effektive Therapeutika im Leipziger Zoologischen Garten bewährt. Dennoch konnte auch in dieser Arbeit die Ätiologie nicht endgültig geklärt werden und bedarf weiterführender Untersuchungen. Ansätze für künftige Forschungsaufgaben bietet die Klärung der möglicherweise generell bei Tigern hereditären Kataraktätiologie und des Hydrocephalus internus bei Amurtigern. Die hohe Diskrepanz der eigenen Ergebnisse im Vergleich zum Schrifttum erfordert weitere Studien an umfangreicherem Material zur Prävalenz von CDV, FIV und FeLV bei Tigern. Bislang nicht im Schrifttum beschriebene Krankheiten (z. B. Obstipation, Hämangiosarkom, Furunkulose, Pyodermie, Härungsanomalien und Panaritien), Infektionen (z. B. mit Gattung Salmonella Saint-Paul, Salmonella enteritidis, Salmonella anatum, Salmonella cholerae suis, Staphylococcus epidermidis und Staphylococcus intermedius) und Infestationen (z. B. Capillaria aerophila) werden in den entsprechenden Kapiteln besonders herausgestellt.
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The ecology of dispersal in lions (Panthera leo)

Elliot, Nicholas Bryant January 2014 (has links)
As ecosystems become increasingly fragmented, there has been a proliferation of research into fields such as resource use, movement ecology and habitat connectivity. To understand how species may adapt to threats associated with habitat fragmentation it is necessary to study these processes in dispersing individuals. However, this is seldom done. Dispersal is one of the most important life-history traits involved in species persistence and evolution, but the consequences of dispersal are determined primarily by those that survive to reproduce. Although dispersal is most effectively studied as a three-stage process (departure, transience and settlement), empirical studies rarely do so and an investigation into the entire process has probably never been carried out on any one species. Here I investigate the survival, resource use, movement ecology and connectivity of African lions (Panthera leo) in all three dispersal phases in addition to adulthood. I make use of a longterm dataset incorporating radio-telemetry and observational data from lions in Hwange National Park, Zimbabwe. Dispersal is inherently risky and my results show that male lions that disperse while young suffer high mortality, young dispersal being brought about by high off-take of territorial males. Dispersing males may be aware of risks associated with territorial adults as they position themselves far from them and utilise habitats and resources differently. However, dispersers, compared to adult males and females, are far less averse of risky, anthropogenic landscapes, suggesting they are the demographic most prone to human-lion conflict. The ontogenetic movement behaviour of lions reflects a transition from directional movement during transience, suggestive of sequential search strategies, to random or periodic use of a fixed territory after settlement. In terms of habitat connectivity, I show that radically different conclusions emerge depending on which demographic is used to parameterise connectivity models. Understanding the shifting mechanisms that species adopt throughout ontogeny is critical to their conservation in an increasingly fragmented world.
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Prey preferences of the Persian leopard and trophic competition with human hunters in Iran

Ghoddousi, Arash 24 August 2016 (has links)
No description available.
50

Isolation and characterization of immunoglobulin G from Panthera leo in South Africa and Zimbabwe

Manamela, Tebogo Sabina 06 1900 (has links)
While a decrease of wild felid population has led to disruption of conservation programme, recent studies have shown the importance of immune regulation for determining health outcomes and co-infection. Immunoglobulin G is important for detecting and evaluating responses to infectious diseases and vaccination. But, there is limited information on felid immunoglobulins and their role for functional immunity. This study aimed at isolating and characterizing lion’s immunoglobulin G. Lions’ sera (n = 68) were processed using the MagReSyn® magnetic beads and the final protein concentration was determined using the Xpose™ Trinean Spectrophotometer. The cross-reactivity of goat anti-cat immunoglobulin with sera of lions and other species was analysed using ELISA. High cross-reactivity was observed in lions ranging from 87.7 to 100%, and low reactivity with rhino (22.4%) followed by chicken (0.01%). The protein concentration from purified sera yielded 39.09 mg/ml. Molecular weight of lion IgG 150-160 kDa was detected with both chains at 54-56 kDa and 24-26 kDa on SDS PAGE. These results indicate a potential aid in developing serological tools to monitor exposure to micro-organisms of lions. / Agriculture and  Animal Health / M. Sc. (Agriculture)

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