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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

The osteology of the cranial and facial bones of the savannah buffalo Syncerus caffer caffer (Sparrman, 1779)

Hornsveld, Marius 08 December 2009 (has links)
Zoologists classify the savannah buffalo under the Bovini Tribe. Osteologically, the skull differs from that of the water buffalo of Asia, inter alia, in that the vomer does not articulate with the palatine part of the osseus palate. This gross anatomical study gives a detailed description of all the bones of the skull, mandible and hyoid apparatus of the savannah buffalo Syncerus caffer caffer (Sparrman, 1779). These bones are similar in many respects to that of the domestic bovine. However, due to the robustness of the buffalo skull, many aspects pertaining to bones or parts of bones that are different or more pronounced, are of anatomical importance. The sum-total effect of all these features, gives the skull its typical macro-morphology that differentiates it clearly from the other genera in the Bovini Tribe. The more important characteristics that were found, are the following: 1. The skull of young animals retains basic embryonic reshaping potential till quite late in life. It can be seen as a remnant of Meckel's cartilage in the mandible as well as in prolonged remodelling in the regions of the orbit, dorsum of the nose, and most markedly, also in the lateral walls of the cranium. A subsequent temporary atypical fontanel can even leave an osseus scar in the temporal region. 2. Temporary canals, associated with the developing permanent premolars, appear in the maxilla and mandible. 3. A well defined biomechanical supporting pillar forms internally in the skull of the buffalo. It conveys pressure from the lingual side of the caudal molar alveoli, to the ipsilateral external lamina of the frontal bone in the region of the frontal fossa. 4. Apart from one small external segment, fusion of the perpendicular and basal plates of the ethmoid bone to the presphenoid bone, in the region of the orbital plate, makes ethmoid-related sutures the least visible sutures to see in all post-natal stages. 5. The retro-orbital position of the cornual process, and the presence of a nasoincisive suture, are some of the osteological features that are shared with the domestic goat. 6. Pneumatization of the nasal bone and dorsal concha may occur, as well as of the tympanic part of the temporal bone. 7. The detail of the sutures other than those of the ethmoid bone, may allow "fingerprint" identification of specific bones or complete skulls. Other applied aspects of the skull may be of importance to hunters and clinicians. / Thesis (PhD)--University of Pretoria, 2002. / Anatomy and Physiology / unrestricted
2

Genetic variation, structure and dispersal among Cape buffalo populations from the Hluhluwe-Imfolozi and Kruger National Parks of South Africa

Greyling, Barend Jacobus 15 July 2008 (has links)
Genetic variation, structure and dispersal among Cape buffalo populations from the Hluhluwe-Imfolozi and Kruger National Parks of South Africa Barend Jacobus (Ben) Greyling Doctor of Philosophy (Zoology) Department of Zoology and Entomology Supervisor: Prof. Armanda Slager-Bastos Co-supervisor: Dr. Pim van Hooft 2007 The research reported on in this thesis is aimed at quantifying and qualifying, using a molecular genetics approach, some of the factors that influence the population dynamics of Cape buffalo (Syncerus caffer caffer) from the Kruger National Park (KNP) and Hluhluwe-imFolozi park (HiP) in South Africa. Prior to large-scale genotyping of animals sampled from these parks, a high-throughput, cost- and time-effective profiling system was developed. The system, based on a panel of 17 microsatellites (Msats), was found to be quite suitable for the intended application, since it uncovered substantial genetic variation, while exclusion probabilities were in excess of 0.999 and a random match probability of 6.5 x 10-17 was obtained. Inter-population level analyses revealed that the two populations were significantly differentiated (Msat data: FST = 0.159; mtDNA data: FST = 0.275), while little or no differentiation could be demonstrated among most herds and subpopulations. It seems that while drift has played a major role in divergence of the two populations, gene flow is the primary driving force behind the maintenance of genetic variation among herds and subpopulations. A striking feature was that HiP exhibited significant lower levels of genetic variation than KNP, which is reflected by the fact that a mere 4 haplotypes could be found in HiP compared to 34 identified in KNP. The absence of geographic partitioning and small genetic distances separating the haplotypes may be attributed to genetic contact between the respective populations in the distant past. The reduced levels of genetic variation in HiP may be the remnants of the rinderpest bottleneck. HiP also displayed signals of a population contraction, while KNP is in equilibrium and seems to have retained substantial levels of genetic variation. HiP also experienced a steady decline in genetic variation from 1986 to 2004, while sex-biased dispersal was less pronounced in HiP than in KNP, possibly due to the lack of mtDNA diversity and the small size of the park. The results presented here provide valuable baseline information for making conservation management decisions from a genetic point of view. / Thesis (PhD (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted

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