Thesis (Maters Diploma (Medical Technology)--Cape Technikon, Cape Town, 1993 / The object of the present study was to determine whether there was a difference in the flux through two different metabolic pathways, the purine salvage pathway and the urea cycle, in skin fibroblasts from three species. A double label approach was adopted to measure the incorporation of the purine bases, hypoxanthine and adenine, and the amino acids, citrulline and arginine in acid precipitable material. Before examining the between species variation it was necessary to examine different levels of possible variation such as the variation between individuals from each species, the variation between separate experiments and the replication error within experiments. Eight individuals from each of three species, bUffalo, human, and rhinoceros were examined with the labelled purine bases. Skin fibroblasts from four humans and eight rhinoceros individuals were also examined over varying passage numbers until the fibroblasts senesced, to determine the effect of ageing on the uptake of hypoxanthine and adenine. The same four human fibroblast cultures were transformed with a transforming virus and examined to see the effects of transformation on the uptake of the purine bases, these transformed fibroblasts were compared with previously transformed rhinoceros fibroblasts. The uptake of labelled citrulline and arginine was also examined in three individuals from each of the three species. The major part of variation throughout the study was found to be at the between experiment level, despite stringently controlled conditions. This between experiment variation obscured any variation found within individuals from each species. In spite of this major between - experiment variation, the results showed that there was significant variation between the three species in the uptake of hypoxanthine. Adenine uptake was similar in the buffalo and human, but was significantly different between both these species and the rhinoceros. citrulline uptake showed no variation between the three species, whereas arginine showed a significant variation between the rhinoceros and the other two species. Buffalo and human showed no significant variation in arginine uptake. There was a significant increase in the uptake of hypoxanthine and adenine in transformed fibroblasts relative to untransformed fibroblasts. As a consequence of the significant between-experiment variation demonstrated in this study, it is apparent that great care must be taken to standardize the conditions when using a double label approach, especially if the assay is to be used for the diagnosis of inborn errors of metabolism.

Thesis (M.S.)--University of Canterbury, 2006. / Title from PDF title page (viewed on Feb. 23, 2008). Includes bibliographical references (p. 86-91).

Thesis (M. Sc.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (leaves 86-91). Also available via the World Wide Web.

Thesis (M.Sc.)--York University, 2003. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 114-120). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ86299

White rhino populations did not occur historically in the Eastern Cape, South Africa (Skead 2007). They have, however, been introduced into a number of reserves within the Eastern Cape for reasons such as conservation, ecotourism and hunting. Based on the literature on the species, it was hypothesized that white rhinoceros would have been introduced in grass-rich habitats, as they are bulk grazers. White rhinoceros populations were further assessed in terms of population establishment by outlining their distribution and performance since introductions and this was done by extracting intercalving intervals from the literature of native populations and comparing such to the Eastern Cape intercalving intervals, extracted from data obtained from landowners. Finally, the diet of white rhinoceros was quantified, in order to identify plant species potentially at risk from white rhino herbivory using Shamwari Private Game Reserve as a study site. The distribution of white rhino in the Eastern Cape varies in terms of habitat and vegetation types. The majority (62%) of white rhino are located in grass-poor habitats and are primarily there for ecotourism purposes with only a small percentage kept for conservation purposes in the state reserves. Limited data for intercalving intervals of the white rhino in Eastern Cape are comparable to those of populations in the natural range. The ex situ conservation of white rhino in the Eastern Cape proved to be a success as population numbers have increased markedly since the first survey was conducted (Buijs 1999). The diet section of this study showed that white rhino are highly selective grazers even in a grass-limiting habitat which is dominated by browse. Twenty-five principal dietary items were identified in their diet, with only six being preferred in autumn. These are thus the plant species that could be the most vulnerable to white rhino herbivory. Supplementary food provision plays a big part of the feeding scheme of white rhino in Shamwari Private Game Reserve during the winter season, revealing the little confidence that the management has on natural resource availability to the animals at this time. These findings support the value of the Eastern Cape for ex situ conservation of white rhino, and highlight plant species potentially at risk. There is a need for further research on the population performance of these animals, and the plants identified here need to be monitored to assess white rhino impact on the vegetation

A..11 species of Tapiridae and Rhinocerotidae are threatened or endangered in the wild. Captive populations have been established for most of these species, but successful management has proved challenging. Effective ex situ conservation strategies, however, rely on the ability of zoological institutions to maintain and breed these endangered species. In this study, I examined the captive environment to identify the factors associated with reproduction, mortality, and health of rhinos and tapirs. Zoological institutions in the North American region that currently housed rhinos and/or tapirs were surveyed in 2003. Attaining an approximately 90% response rate, I compiled information on the following variables to describe the captive environment: number of enclosures, enclosure type, enclosure area, number of animals, public viewing, percent of walls surrounding the enclosure, enclosure substrate, topography, vegetation, mud wallows, pools, shelters, percent shade, climate, diet, feeding regime, time spent by keepers, and vaccinations. Information regarding the incidence of health problems also was obtained through the survey. Studbook data was used to obtain life history and demographic information. Three species of tapirs [Baird's (Tapirus bairdii), South American (T. terrestris), and Malay (T. indicus)] and three species of rhinos [black (Diceros bicornis), white (Ceratotherium simum), and Indian (Rhinoceros unicornis)] were included in this study. Due to the small captive population sizes, genetic and demographic Allee effects were detected. While tapirs responded similarly to their captive environment, each rhino species responded differently. Both exhibit area and completely were associated with the responses of captive tapirs and rhinos. Climate also was an influential factor for both groups of species. Other key factors included density, diet, keeper time, percent of public perimeter, and vaccinations. Complex interactions among the variables were found, including a nonlinear relationship between mean exhibit size and reproduction for black rhinos. The results of this study can be used to improve the captive management of tapirs and rhinos. By identifying the patterns associated with successful reproduction, reduced mortality, and fewer health problems, we can move towards establishing self-sustaining populations for these species. This goal is critical for the continued husbandry and conservation of these species.

Thesis (PhD (Veterinary Tropical Diseases, Veterinary Science))--University of Pretoria, 2009.

Please read the abstract in the 00 front of this document. / Thesis (PhD)--University of Pretoria, 2009. / Veterinary Tropical Diseases / unrestricted

Thesis (MTech. degree in Nature Conservation.)--Tshwane University of Technology, 2010. / To a varying degree and for a variety of reasons black rhino require large areas of land but increasingly they are moved to smaller properties. Specific spatial and temporal problems are foreseen when keeping black rhino on small properties. The temporal problems under investigation on the Mokopane Biodiversity Conservation Centre where two black rhino are kept on 700 ha are: browse availability, browse utilisation as well as browse quality.

Black rhinoceroses (Diceros bicornis) have been extirpated from most of their historic range with the remaining individuals (ca. 5200) living in geographically isolated populations. Management priorities include creating new populations whilst maintaining genetic diversity and promoting gene flow between existing isolated populations. Such objectives are however currently hindered by a lack of comparative/reference data on levels of diversity, relatedness and inbreeding in a large, free-ranging black rhinoceros population. Here I attempt to address this gap in our knowledge by investigating the genetic diversity of the black rhinoceros Diceros bicornis minor within Kruger National Park (the largest free-ranging population of this subspecies) using nuclear and mitochondrial DNA. I compared the diversity of this founded population with the two source populations (KwaZulu-Natal, South Africa and Zimbabwe) using published studies, and evaluate the relative contribution of source lineages relative to the proportion of original founders. Analysis of the mtDNA control region revealed four haplotypes, with moderate haplotype and nucleotide diversity (h=0.48 (± 0.05 SD); π= 0.29%). Data from 13 microsatellite loci revealed moderate to high levels of genetic variation (number of alleles = 4.92 ± 0.90, effective number of alleles = 2.26 ± 0.25, observed heterozygosity = 0.50 ± 0.04, expected heterozygosity = 0.51 ± 0.04), low mean pairwise relatedness (r = -0.03), a low inbreeding coefficient (Fis = 0.04) and no evidence of genetic structuring. Diversity levels within the Kruger black rhinoceros population were high compared to levels reported in black rhinoceroses originating in KwaZulu-Natal and similar to those reported in individuals originating in Zimbabwe. Results show that 40-60% of the Zimbabwean lineages are represented in the Kruger population which is a noticeable increase in the relative contribution of the Zimbabwe founder population. The data provided by this study can be used to guide management and conservation decisions regarding maximising genetic variability across the subspecies. Furthermore, given the encouraging levels of genetic diversity observed, the Kruger black rhinoceros population would be an ideal source population for supplementation of genetically depauperate populations or creating new populations. Finally, these findings demonstrate a positive outcome in mixing the KwaZulu-Natal and Zimbabwe gene pools, with evidence that the founder Kruger black rhinoceros population has been genetically rescued from the low diversity seen in the KwaZulu-Natal black rhinoceroses in South Africa.