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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.
31

A homoeopathic drug proving of ivory from the male African elephant (Loxodonta africana) with a subsequent comparison to Lac Loxodonta africana

Forbes, Barry January 2008 (has links)
Thesis (M.Tech.: Homoeopathy)--Durban University of Technology, 2008 / Introduction This dissertation entails a homoeopathic proving of ivory from the male African elephant (Loxodonta africana) 30CH with a subsequent comparison to Lac Loxodonta africana. Objectives The primary objective of this proving was to determine the effects of homoeopathically prepared ivory from the male African elephant (Loxodonta africana) in a 30CH dilution and was achieved by administering the remedy to a group of healthy individuals (provers) who will document all symptoms that arise as a result of taking the remedy. These symptoms will be used to identify the therapeutic indications of homoeopathic ivory. With these specific indications being documented the remedy can then be utilized in the sick individual, that present with similar symptoms, to induce a cure. A further objective of this proving is to report any variation that may exist in the comparison of two remedies, namely Lac Loxodonta africana (milk derived from the African elephant) and the remedy used in this proving, ivory from the male African elephant (Loxodonta africana). Methodology The substance was triturated up until the 3CH and subsequently converted into a liquid potency to be potentised up until the 30CH. Granules were then impregnated with the 30CH liquid potency. Ten impregnated granules were then placed in each individual ii lactose powder sachets. A total of six powders were dispensed to the proving participants. The proving was conducted as a double blind placebo controlled study with a total of twenty-six (26) provers that met the inclusion criteria (Appendix A). The group was made up of both homoeopathic students as well as the general public of varying ages, race and gender. The total group was randomly divided into two groups, twenty (20) of which received the homoeopathic remedy, the remainder (6) received placebo. A full case history of each prover was taken before commencing the proving as well as on completion of the study. Each individual prover kept a journal, starting a week before the proving, which was continued while taking the remedy and ceased when all symptoms had abated. Once all provers had completed the proving, the information received from the provers through the journals from both groups was collated, assessed and analyzed. A comparison was then made between this proving and Lac Loxodonta africana to assess whether any similarities or differences were evident. The comparison was made on symptom similarities and rubric analysis. Results The proving of ivory from the African elephant (Loxodonta africana) revealed a variety of symptoms. A total of 32 systems were affected in the twenty provers who received the remedy. 716 symptoms were recorded, 83 of which were new symptoms. The systems that were predominately affected were the mind, head and extremities. Many symptoms were confirmed to be similar to those identified in the proving of Lac Loxodonta africana, though differences were also acknowledged.
32

A homoeopathic drug proving of ivory from the male African elephant (Loxodonta africana) with a subsequent comparison to Lac Loxodonta africana

Forbes, Barry January 2008 (has links)
Thesis (M.Tech.: Homoeopathy)--Durban University of Technology, 2008 / Introduction This dissertation entails a homoeopathic proving of ivory from the male African elephant (Loxodonta africana) 30CH with a subsequent comparison to Lac Loxodonta africana. Objectives The primary objective of this proving was to determine the effects of homoeopathically prepared ivory from the male African elephant (Loxodonta africana) in a 30CH dilution and was achieved by administering the remedy to a group of healthy individuals (provers) who will document all symptoms that arise as a result of taking the remedy. These symptoms will be used to identify the therapeutic indications of homoeopathic ivory. With these specific indications being documented the remedy can then be utilized in the sick individual, that present with similar symptoms, to induce a cure. A further objective of this proving is to report any variation that may exist in the comparison of two remedies, namely Lac Loxodonta africana (milk derived from the African elephant) and the remedy used in this proving, ivory from the male African elephant (Loxodonta africana). Methodology The substance was triturated up until the 3CH and subsequently converted into a liquid potency to be potentised up until the 30CH. Granules were then impregnated with the 30CH liquid potency. Ten impregnated granules were then placed in each individual ii lactose powder sachets. A total of six powders were dispensed to the proving participants. The proving was conducted as a double blind placebo controlled study with a total of twenty-six (26) provers that met the inclusion criteria (Appendix A). The group was made up of both homoeopathic students as well as the general public of varying ages, race and gender. The total group was randomly divided into two groups, twenty (20) of which received the homoeopathic remedy, the remainder (6) received placebo. A full case history of each prover was taken before commencing the proving as well as on completion of the study. Each individual prover kept a journal, starting a week before the proving, which was continued while taking the remedy and ceased when all symptoms had abated. Once all provers had completed the proving, the information received from the provers through the journals from both groups was collated, assessed and analyzed. A comparison was then made between this proving and Lac Loxodonta africana to assess whether any similarities or differences were evident. The comparison was made on symptom similarities and rubric analysis. Results The proving of ivory from the African elephant (Loxodonta africana) revealed a variety of symptoms. A total of 32 systems were affected in the twenty provers who received the remedy. 716 symptoms were recorded, 83 of which were new symptoms. The systems that were predominately affected were the mind, head and extremities. Many symptoms were confirmed to be similar to those identified in the proving of Lac Loxodonta africana, though differences were also acknowledged. / M
33

A comparative cognition perspective on the production and use of visual signals by African savannah elephants (Loxodonta africana)

Smet, Anna F. January 2015 (has links)
Elephants' complex societies, well-developed communication systems, evolutionary history and close working relationship with humans make them an important species for studies of cognition but research on elephant cognition is sparse. In this thesis I aim to illuminate the social cognition involved in the interpretation and production of visual signals by African elephants (Loxodonta africana). My results are intended to contribute to the cross-species literature on social cognition and help to elucidate wild elephant social behaviour. I studied captive elephants, housed at an elephant-back safari company in Victoria Falls, and wild elephants in Hwange National Park, both in Zimbabwe. Wild elephants display a vast array of postures, actions and signals. I found that elephants recognise visual attentiveness in others when they signal silently, producing more signals when their audience can see them, and using the body and face orientation of an audience to judge their attention. When responding to typically human visual signals, elephants immediately responded correctly to deictic gestures, including variants of pointing that they were unlikely to have already experienced. These results indicate elephants' astonishing sensitivity to even subtle social cues. I found no indication that elephants reason about mental states such as false beliefs, or rationality; however, limitations of the experimental design meant I was unlikely to find such an ability even if it is present in elephants. Furthermore, I discovered that elephants have a form of referential indication in their natural communication in the wild. Elephants match their direction of attention with a type of trunk action produced by a group member. Attending to human-like signals, and interpreting them as communicative is an advantage for any animal working with humans and that ability might explain the choice of species that are ancestors of today's domestic animals.
34

Environmental stochasticity and African elephant population dynamics : investigating limitation through juvenile mortality.

January 2008 (has links)
The successful conservation management of African elephants depends largely on understanding the fundamental processes driving the population regulation of this species. Southern Africa’s increasing populations have raised concern over the impact of high elephant densities on the system, in stark contrast against the elephant’s more precarious position in other parts of Africa. As we search for solutions from the processes of historical elephant regulation, we realise that there is a decided lack of empirical evidence to explicitly direct our efforts. In this PhD, I attempt to investigate the application of the classic pattern of large herbivore population limitation, which mainly involves high juvenile mortality in response to stochastic environmental events, to African elephant population dynamics. Firstly, I evaluated the magnitude and frequency of mortality events that would be required to prevent elephant population growth. The death of 85 % of infants and weaned calves would need to occur twice a generation, while a single severe mortality event (causing the death of all infants and weaned calves and 10 % of the rest of the population) once a generation would be sufficient. However, the severity of these events is not matched in natural occurrence in Africa today and only a single recorded event in Tsavo National Park, Kenya, in the 1970’s has come close when more than 7 000 died during a very severe drought. Secondly, I evaluated the potential role of fire as a stochastic, massmortality event limiting elephant populations. I found that fire functions in a similar manner to other environmental catastrophes and primarily causes high juvenile mortality. However, this catastrophic event also highlighted the extreme behavioural and physiological impacts experienced by the elephant population involved. The potential role of these types of events on long-term female fecundity needs further investigation. In isolation, this type of mortality event would need to occur with high frequency to prevent population growth. However, in combination with a decrease in female fecundity, these stochastic events may have a much greater impact on population demography than first thought. Thirdly, I investigated a potential mechanistic link between stochastic mortality events and juvenile susceptibility to resource limitation. Allometric relationships dictate that juveniles select a diet of higher quality than adult elephants. We found that this was achieved by weaned calf selection of higher quality plant parts, although use of plant types and plant species was similar to that of adult females, who they move across the landscape with. The strong sexual dimorphism exhibited by this species was reflected in adult male use of lower quality forage than adult females (or juveniles) in both dry and wet seasons. Diet quality scaled negatively with body size, but adult females consistently selected a higher quality diet than adult males, irrespective of body size. The nutritional and reproductive demands placed on an individual during different life-history stages therefore influence foraging strategies, together with nutrient requirements, e.g. phosphorus for pregnancy/lactation selected consistently by females when unrestricted in the wet season, protein for growth selected consistently by weaned calves. Competitive displacement of adult females to feed at higher levels in the canopy by calves also influenced feeding behaviour. Therefore intraspecific body size, nutritional requirements (in terms of nutrients and energy) and competition had a strong influence on foraging strategy employed by age-sex classes of elephants in response to seasonal environmental change. More selective juvenile foraging requirements means that juveniles are most susceptible to resource limitation, for example during stochastic environmental events such as droughts. In small, closed systems, juvenile mortality is likely to have a strong influence on elephant population regulation, with a slight, temporary decrease in female fecundity possibly acting in conjunction with juvenile mortality effects. Therefore, stochastic environmental events such as drought and fire may be the only natural incidence of population regulation to occur in these systems, where populations continue to grow exponentially and there is no evidence of density-dependence (as in the case of many small, fenced reserves in South Africa). In large, open, high-density systems in other parts of southern Africa, density dependence acts strongly on female fecundity and causes low levels of juvenile mortality in areas of local population aggregation. Therefore, in isolation, natural juvenile mortality is unlikely to regulate African elephant populations, but in conjunction with decreased female fecundity in response to density-dependent feedbacks and stochastic environmental events, population regulation may occur. The management of long-lived megaherbivore species with similar demographic drivers must include an appreciation of the complexity of population response to manipulation of mortality or fecundity effects. Small changes can potentially result in large shifts in population dynamics. Further insight into the mechanisms driving these processes will allow sound scientific support of megaherbivore management decisions to be made throughout Africa. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2008.
35

What drives the seasonal movements of african elephants (Loxodonta africana) in Ithala Game Reserve?

Muller, Kayleigh. January 2013 (has links)
The changes in plant quality and availability in space and time present a substantial problem to mammalian herbivores. As a result, these herbivores need to alter their foraging behaviour to maximize their energy gain at both small (plant level) and large (landscape level) scales. A megaherbivore, the African elephant (Loxodonta africana), has been shown to be selective in its foraging choices at both of these scales. Furthermore, the ratio of palatability:defences (e.g. fibre and total polyphenols) has been highlighted as an important determinant of habitat selection in elephants. The elephants in Ithala Game Reserve (IGR) frequently leave IGR during the wet season and forage outside the reserve. However, they predominantly feed on the low-nutrient granite soils of the reserve and return to a high-nutrient area with dolerite soils during the dry season. In an attempt to understand these seasonal movements, I focused on how the small-scale foraging decisions of the elephants lead to large-scale seasonal movements in IGR, KwaZulu-Natal. Plant availability was determined seasonally for seven target species across four areas in the reserve. Crude protein, fibre, energy and total polyphenols as well as the ratios of palatability:digestion-reducing substances were analysed in the wet and dry seasons. All factors and their interactions were significant in a MANOVA. Consequently, I employed a dimension-reducing Principal Components Analysis (PCA) to better understand the factors of greatest importance. The PCA highlighted four of the six most important factors to be the ratios of palatability:digestion-reducing substances. The other two important variables were total polyphenols (negative effect) and crude protein (positive effect). At small spatial scales, I found that the elephants were selective in their decisions, especially during the dry season. For example, the increased inclusion of the principal tree species Acacia nilotica from 2.9% in the wet season to 39.3% during the dry season appears to be a result of a decline in total polyphenols and fibre during the dry season. At large spatial scales, the elephants moved back into IGR from the low-nutrient granite soils in the east in response to an increase in forage quality in the west as the quality declined in the east at the same time. However, it is unclear as to why the elephants are leaving the reserve during the wet season. Some possible explanations for this are discussed.Key-words: acid detergent fibre, crude protein, Loxodonta africana, neutral detergent fibre, total polyphenols, plant part quality. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.
36

The effect of elephant utilisation on the Sterculia rogersii and Adansonia digitata populations of the Kruger National Park

Kelly, Henry Lyle Patrick. January 2000 (has links)
Thesis (M. Sc.)--University of Pretoria, 2000. / Title from PDF t.p. (viewed on July 17, 2006). Includes bibliographical references (p. 118-122).
37

An assessment of perceived crop damage in a Tanzanian village impacted by human-elephant conflict and an investigation of deterrent properties of African elephant (Loxodonta africana) exudates using bioassays

Karimi, Rebekah R. Schulte, Bruce A. January 2009 (has links) (PDF)
"A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." Title from PDF of title page (Georgia Southern University, viewed on June 19, 2010). Bruce A. Schulte, major professor; Lissa M. Leege, J. Michelle Cawthorn, committee members. Electronic version approved: December 2009. Includes bibliographical references (p.76-78).
38

Prvky chování slona afrického (Loxodonta africana, Blumenbach 1797) / Behavioral Elements in African Elephant (Loxodonta africana)

Křivánek, Ondřej January 2015 (has links)
My master's thesis is about the African elephant (Loxodonta Africana) and is aimed at different behavior elements. These behavior elements were observed in captivity in the ZOO Dvůr Králové and than in the wild in Africa. Observation in wild were carried out on different individuals in various national parks. Overall results were compared and I made from them conclusions about the impact of captivity breeding on the individuals. Key words: african elephant, behavior, captivity, wild Powered by TCPDF (www.tcpdf.org)
39

Botswana’s Elephant-Back Safari Industry – Stress-Response in Working African Elephants and Analysis of their Post-Release Movements

Lama, Tanya 11 July 2017 (has links)
Understanding how African elephants (Loxodonta africana) respond to human interactions in ecotourism operations is critical to safeguarding animal and human welfare and sustaining wildlife ecotourism activities. We investigated the stress response of elephants to a variety of tourist activities over a 15-month period at Abu Camp in northern Botswana. We compared fecal glucocorticoid metabolite (FGM) concentrations across three elephant groups, including: eight elephants in an elephant-tourism operation (Abu herd), three elephants previously reintroduced back into the wild from the Abu herd, and wild elephants. There were no differences in FGM concentrations between the three groups of elephants. The highest observed FGM concentrations were associated with episodic events (e.g. intraherd conflict, loud noise, physical injury) unrelated to tourist activities. FGM concentrations differed between the elephant-tourist activities with ride only and mixed ride/walk activities eliciting higher FGM concentrations compared to days when there were no elephant-tourist interactions. The elephant experience tourism industry faces challenges in managing elephants who’s aggressive or unpredictable behavior makes them ill-suited to captivity, training, and interaction with handlers and tourists. Reintroduction of these elephants back into the wild may be a favorable solution if the welfare of released individuals, recipient wild animal populations, and human populations can be ensured. We describe the post-release movements of two African elephants, one female and one bull, from an elephant-back-safari enterprise in the Okavango Delta, Botswana. We compared the movements of the female with that of two wild females collared in the same wildlife management concession. We assess their home range size, proximity to human dwellings, and fidelity to their former home range as former members of their semi-captive, working herd from which they were released. We found significant differences between the home range size of our released elephant and that of the two wild elephants. Additionally, the released female and released bull occurred more frequently in close proximity (within 250 m) to tourist lodges throughout the Delta. The released elephants also frequented sites used by the working Abu herd with greater frequency than the wild elephants, and this visitation rate did not significantly decline during respective four- and two-year post-release monitoring periods, despite the positive growth in home range size.
40

Long-term monitoring of elephant impact on the woody vegetation in the Tembe Elephant Park, South Africa

Potgieter, Mary-Lee 21 June 2013 (has links)
The African Elephant is a key component of the savanna ecosystem. They contribute to the generation of habitat for smaller vertebrates, as well as invertebrates, by the breaking of branches or uprooting of trees. Elephants also play a role in seed dispersal, germination and sapling recruitment. All these functions are advantageous to the ecosystem if the elephant population size is acceptable for the size of the reserve and the amount of available forage. The Tembe Elephant Park covers an area of 30 013 ha and is situated in northern KwaZulu Natal. This reserve has a diversity of vegetation types and is part of the Maputaland Centre of Plant Endemism and the Maputaland-Pondoland-Albany Hotspot of Biodiversity. Elephant numbers in the park are currently high and the elephant population is still increasing. This is threatening, especially to the endemic Sand Forest communities within the park. The extent of elephant impact in Tembe Elephant Park, South Africa, was investigated and compared to data collected six years prior to the current study. Elephant impact was determined in 44 transects within nine communities across the park. Percentage canopy removal was calculated for the woody individuals found in sites and with this data the targeted size classes and species could be identified. The preferences of elephants for specific woody species were determined by three electivity indices. Elephant utilisation in Tembe Elephant Park, as reflected by percentage canopy removal, increased since 2004 as the elephant population increased. Communities that experienced high values in 2010 of elephant utilisation were the Closed Woodland 1, Mature Sand Forest, Open Woodland 1 and the Closed Woodland 3. Not only did the actual canopy volume removed by elephant increase with approximately 57%, but the total canopy volume available for browsing decreased extensively since 2004. The size classes targeted by the elephants remained approximately the same from 2004 to 2010 although the 2010 results showed that elephant canopy removal percentage increased in the large size classes. This was expected as elephants target individuals with large stem diameters. A change in the selection for woody species by elephants was clear, but the change in species preference made future projections of canopy removal problematic. Elephants seem to utilise a species at extreme levels until the species is almost extirpated, then they move onto the next target species. This routine is evident in the results as highly preferred species in 2004, with high canopy volumes available and removed, had low canopy availability and electivity ratios in 2010, consequently the elephants moved on from these species as individuals became scarce. It was clear that the structure of individuals, populations and communities were being altered, selected species were facing extirpation and composition of communities was changed through the browsing manners of elephants. Management actions should be implemented to prevent irreversible damage to the vegetation and to conserve the woody species currently under threat. / Dissertation (MSc)--University of Pretoria, 2012. / Plant Science / MSc / Unrestricted

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