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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.
1

Factors affecting the mortality of pronghorn antelope in Oregon /

Yoakum, James Donovan. January 1957 (has links)
Thesis (M.S.)--Oregon State College, 1957. / Typescript. Includes bibliographical references (leaves 96-105). Also available on the World Wide Web.
2

The comparative histomorphology and corticosteroid profile of adrenal glands in some African antelopes /

Fazakas, Andrew S. January 1996 (has links)
Adrenal glands from five species of South African antelope; cape eland (Taurotragus o.oryx), gemsbok (Oryx g.gazella), southern greater kudu (Tragelaphus s.strepsiceros), red hartebeest (Alcelaphus buselaphus caama), springbok (Antidorcas marsupialis hofmeyri), were collected from 43 trophy-hunted males for histology and corticosteroid analysis. The gross anatomy of the adrenal glands are species-specific, with the left gland being most variable. There were differences found in the number of cortex capsular layers and zona glomerulosa between species. Extensive capsular trabeculae penetrates deep into the cortex in only the largest antelope, i.e. eland and gemsbok, and are representative of these species. In all species the zona glomerulosa form variations in types of cellular cord structures, with the greater kudu having the most unique architecture of horizontally stratified, highly columnar cells that form winding cords which arches at the capsular end, and resemble those observed in equine species. Medullary capsules were observed in the eland, and incomplete capsules in the gemsbok and greater kudu. The medulla is characterized by an outer, adrenaline secreting zone that encapsulates a inner noradrenaline secreting zone in all species. The corticosteroid patterns are typical of bovids, with cortisol and corticosterone present, however significantly larger amounts of 18-hydroxy-corticosterone were found in all species of antelope. The total identified corticosteroid contents had interspecies differences, which are possibly based on species body size.
3

The comparative histomorphology and corticosteroid profile of adrenal glands in some African antelopes /

Fazakas, Andrew S. January 1996 (has links)
No description available.
4

Detection of hyperthermia during capture of wild antelope

Broekman, Marna Suzanne 29 January 2013 (has links)
Capture of wildlife often leads to high animal mortality. In many species, capture is associated with development of a high body temperature. This stress-induced hyperthermia appears to form an integral part of capture-related mortalities, since it occurs before, during and after exposure to capture. I used two wildlife species, impala and blesbok, and exposed them to darting and net capture so as to investigate thermal and haematological changes that occur during capture. We implanted the animals with temperature-sensitive data loggers within the abdominal cavity (for core body temperature) and caudal aspect of the thigh (for muscle temperature). Activity loggers were tethered to the abdominal wall to measure locomotor activity. Blood samples were taken after capture when the animal became recumbent and another sample 10 minutes after the first sample in order to determine haematological changes. Impala had higher abdominal body temperatures during net capture in comparison to darting, whereas blesbok abdominal body temperatures did not differ between capture methods. Different species and individuals of the same species respond differently to various capture procedures. However, I found that irrespective of the capture event or whether impala or blesbok were captured, human presence before capture caused abdominal body temperatures to rise. Similar to thermal responses, there also was high variability between individuals in terms of blood variable concentrations used to quantify physiological responses to capture. Overall, blood variable changes (total protein, sodium, lactate, haematocrit, noradrenaline, adrenaline, potassium, creatine phosphokinase, pH) were similar for impala and blesbok in response to the two capture procedures. Cortisol values in blesbok however showed a greater response during darting whereas impala showed a greater response during net capture. Similarly, osmolality values showed a greater response during net capture whereas impala showed a greater response during darting. Both the species showed that sodium and lactate correlated positively as well as noradrenaline and adrenaline correlated positively. The correlation between two variables allows us to measure only one of the variables, predicting the change of another. Unpredictable differences in thermal and blood variable measurements of impala and blesbok between different capture procedures did not allow me to correlate the thermal responses after a capture event to stress-related blood variables. The issue of obtaining a practical and accurate measurement of the hyperthermic response during capture also often arises. Rectal temperature is currently the method of choice to determine body temperature in the field. I aimed to investigate whether muscle temperature measurement can be used as an alternative body temperature measurement in the field. When abdominal core body temperatures were high, muscle temperature measurements were close to and even slightly higher than the abdominal body temperature measurements in both the species. However, low abdominal body temperatures, muscle temperature measurements were at lower and much less accurate in predicting abdominal body temperatures. Muscle temperatures can therefore predict abdominal body temperatures with sufficient accuracy during a capture event, since animals respond to capture with elevated body temperatures thus increasing the similarity between the abdominal and muscle temperature measurements measured. One potential problem with muscle temperature, is that it may reflect exercise-induced temperature increases during capture, independently of a rise in abdominal body temperature. I found that the rise in muscle temperature was not only a result of the increase in activity during a capture event but rather as a result of stress-induced hyperthermia. The increase in activity only contributes to the overall hyperthermia of the animal. The degree to which stress-induced hyperthermia contributes to mortality during capture is unclear. During my study, five impala died unexpectedly. Four impala died during the first trial while the fifth impala died before the completion of the last trial. I therefore compared the hyperthermic and haematological changes in surviving and non-surviving individuals. Both non-surviving and surviving impala in my study showed a rise in abdominal body temperature during the capture however the highest abdominal body temperatures occurred in individuals in both the surviving and non-surviving group. Very high abdominal body temperatures greater than 41ºC and 43ºC occurred in individuals of both the non-surviving and surviving animals, respectively. Some animals with an abdominal body temperature of 43ºC, therefore survived whereas other individuals died when experiencing abdominal body temperature of less than 41ºC. Blood variable responses (Creatine phosphokinase, glucose, potassium, calcium, sodium, lactate, osmolality, noradrenaline, adrenaline, pH) of the non-surviving individuals showed high values in comparison to the blood variable measurements of the surviving group. The blood variable measurements were however sampled late which will affect the measurements but can still be used to predicted mortality in the non-surviving impala. The blood variable measurements therefore were associated with mortality in the non-surviving impala. In conclusion, whether stress-induced hyperthermia can be used as a sole measure to identify a compromised individual during a capture event and concomitantly enable us to give appropriate treatment is unclear. It is evident from my study that capture induced a hyperthermic response in excitable impala as well as in the much less excitable blesbok. My study is one of few systematic studies on capture stress and shows that body temperature used in conjunction with other parameters may be useful in estimating the degree of stress in captured animals, and thus predicting likelihood of mortality or morbidity. My study also revealed that muscle temperature, possibly measured in the field by a needle-stab method, may provide an index of core body temperature.
5

An outline of the ecology and behaviour of the red lechwe (Kobus leche leche Gray, 1850)

Williamson, Douglas Templin. 10 September 2014 (has links)
In a number of publications serious concern has been expressed about 'the status of lechwe in the Kwando/Linyanti/Chobe system. Concern has also been expressed about the effects of possible water extraction from the Okavango Delta on the habitat of lechwe in the delta. This study was motivated by this concern and was undertaken to provide information that would facilitate the conservation and management of lechwe in Botswana. Continuous field work on the western edge of the Linyanti Swamp began in January 1975 and ended in May 1977. Follow-up visits were made in February/March and September/October 1979. Data were collected on the following: variation in water l6vels, physiognomic and floristic characteristics of lechwe habitat, age determination, food habits, habitat use, distribution,condition growth, reproduction, non-social behaviour, social behaviour and organjsation and population status. From data collected it was concluded that, although there was no indication of a drastic population decline, the prevailing high water levels in the system were causing a downward trend in the population by pushing the animals into poorer quality habitat. The decline in the quality of the habitat available to the population was reflected by high juvenile mortality and reduced fecundity of young females. On the basis of the findings of this study a strategy for the conservation and management of lechwe in the Linyanti Swamp is proposed. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1980.
6

Molecular phylogenetics and conservation aspects of antelopes

Rebholz, Wilhelmus Ewald Reinaard January 1996 (has links)
This thesis concerns the molecular phylogenetics of three tribes of the family Bovidae, the Antilopini, Neotragini, and Tragelaphini. None of these tribes have been studied extensively with molecular techniques. The tribe Antilopini is one of the most speciose tribes (it includes 6 genera with 20 species) and the classification of several species of the genus Gazella is not clear. The tribe Neotragini is thought to be paraphyletic. Mitochondrial sequences of the cytochrome c oxidase ill and cytochrome b genes totalling 1083 base pairs have been determined for 52 taxa and used to determine phylogenetic relationships using cladistic and distance methods. Karyological analysis identified polymorphisms in several species (especially in Gazella saudiya and G. subgutturosa). Karyotypes of G. dorcas pelzelni and an XXY karyotype of a G. dorcas individual are shown for the first time. The main conclusions are that the Antilopini and the Tragelaphini are monophyletic and that the tribe Neotragini is paraphyletic. There is a lack of phylogenetic resolution between tribes which is probably due to the rapid radiation of the different tribes about 20 million years ago. The genus Taurotragus in the tribe Tragelaphini is shown to be paraphyletic and it would be appropriate to incorporate these taxa in the genus Tragelaphus. The genus Gazella could be paraphyletic, due to the position of Antilope cervicapra, in which case the genus needs to be split into two genera or renamed as Antilope. It is also argued that the use of the subgenus Trachelocele should be discontinued and that its only species, G. subgutturosa should be included in the subgenus Gazella. G. rufifrons and G. thomsonii may be more appropriately considered as conspecific. Cytogenetic and sequence data reveal that the herd of G. saudiya in Al Areen Wildlife Park is hybridised with G. bennettii and it is argued that it is important to identify unhybridised G. saudiya in other collections, since this species is on the brink of extinction. This case study demonstrates the need to genetically screen individuals which are part of a captive breeding program, especially if they are intended for reintroduction into the wild.
7

A GIS based habitat suitability analysis of the Oribi antelope in KwaZulu-Natal /

Hill, Andrew. January 2009 (has links)
Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009. / Full text also available online. Scroll down for electronic link.
8

Mechanics and function of territorial behaviour in klipspringer

Roberts, Stewart Craig January 1994 (has links)
No description available.
9

The prevalence of helminths in warthogs, bushpigs and some antelope species in Limpopo Province, South Africa

Conradie, Ilana. January 2008 (has links)
Thesis (MSc (Veterinary Tropical Diseases.))--University of Pretoria, 2008. / Includes bibliographical references. Also available in print format.
10

The molecular evolution of the spiral-horned antelope (Mammalia: Tragelaphini)

Willows-Munro, Sandi 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: The evolutionary history of the African tribe Tragelaphini (spiral-horn antelope) is controversial. Past phylogenetic relationships among species were based on morphology or limited fossil evidence and are in conflict with mitochondrial DNA sequencing studies that have been conducted more recently. Although the group is distinguished from other African ungulates by the presence of spirally-twisted horns, the nine recognized extant species differ considerably in morphology, feeding habits and their habitat preference. The present study aims to resolve the phylogenetic uncertainties of the Tragelaphini using nuclear DNA sequence data derived from four independent DNA loci (MGF, PRKCl, SPTBN and THY). These data were combined with all previously published DNA sequences to produce a molecular supermatrix comprising approximately 6000 characters. Both parsimony and model based phylogenetic analyses of the nuclear DNA support the associations resulting from the analysis of mitochondrial genes. These findings suggest that the morphological characters previously used to delimit species within the group are subject to convergent evolution. The molecular phylogeny presented herein suggests that early members of Tragelaphini diverged from the other bovids during the mid-Miocene approximately 15.7 million years before present (MYBP). The common nyala (Tragelaphus enqest; and lesser kudu (Tragelaphus imberbis) representing the most basal species, separated from the other tragelaphids approximately 7.1 MYBP. This was subsequently followed by the radiation of those species adapted to a more tropical environment and they include the mountain nyala (Tragelaphus buxtom), bongo (Tragelaphus euryceros), sitatunga (Tragelaphus spekel) and bushbuck (Tragelaphus scriptus), and the arid adapted clade comprising the giant eland (Taurotragus derbianus), common eland (Taurotragus oryx) and greater kudu (Tragelaphus strepsiceros). It is thought that this split occurred at the Miocene-Pliocene boundary approximately 5.4 MYBP. The timing of evolutionary events within the tribe suggests climatic oscillations and subsequent biotic shifts as the major driving forces underpinning speciation in the tribe Tragalaphini. / AFRIKAANSE OPSOMMING; Die evolusionêre geskiedenis van die ras Tragelaphini (spiraalhoringwildsbokke) is kontroversieël. Vorige filogenetiese verwantskappe tussen die spesies is gebaseer op morfologie of beperkte fossiel bewyse. Meer onlangse studies, gebaseer op mitochondriale ONS nukleotieddata, is in teenstryding met baie van die evolusionêre hypotese afkomstig van morfologiese studies. Alhoewel die groep van die ander hoefdiere uitgeken kan word deur die aanwesigheid van spiraalvormige horings, verskil die nege hedendaagse spesies grootliks ten opsigte van morfologie, voedingswyse en habitat. Die hoof doelwit van hierdie studie was om die filogenetise verwantskappe tussen die Tragelaphini spesies te ontleed deur gebruik te maak van nukluêre ONS nukleotieddata afkomstig van vier onafhanklike ONS merkers (MGF, PRKCl, SPTBN en THY). Die data verkry is saamgevoeg by vorige gepubliseerde ONS nukleotidedata om 'n "supermatris" van sowat 6000 karakters te produseer. Parsimonie en modelgebaseerde filogenetise analise van die nukluêre ONS nukleotieddata het ooreengestem met die resultate van vorige mitochondriale studies. Hierdie bevindings dui daarop dat die morfologiese karakters wat voorheen gebruik is om die evolusionêre verwantskappe tussen die Tragelaphini spesies te ontleed onderhewig is aan konvergente evolusie. Die molekulêre filogenie wat hierin beskryf word stel voor dat die ras Tragelaphini gedurende die mid- Miocene, omtrent 15.7 miljoen jaar (MJ) gelede van die ander lede van die subfamilie Bovinae geskei het. Tragelaphus angasi en Tragelaphus imberbis, die mees basale spesies in die filogenie, het omtrent 7.1 MJ gelede van die ander lede van die Tragelaphini geskei. Hierdie skeiding is gevolg deur 'n split tussen die spesies aangepas vir 'n meer tropiese habitat (Tragelaphus buxtoni, Tragelaphus euryceros, Tragelaphus spekei en Tragelaphus scriptus) en die spesies aangepas vir 'n droë habitat (Taurotragus derbianus, Taurotragus oryx en Tragelaphus strepsiceros) Hierdie finale skeiding het gedurende die Miocene-Pliocene oorgang plaasgevind. Die tydsberekening van die evolusionêre gebeurtenisse wat binne die Tragelaphini ras plaasgevind het, gekoppel aan paleoklimaatdata, dui aan dat veranderinge in klimaat en die geassosieerde habitatveranderinge verantwoordelik was vir die spesiasie patroon wat ons vandag in die Tragelaphini ras waarneem.

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