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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.
21

Evaluation of varied enrichment schedules for two feline and one primate species at Parken Zoo

Gustavsson, Linda January 2011 (has links)
An evaluation of varied enrichment and feeding schedules were conducted on three spices, drill, Pallas’s cat and cheetah, at Parken Zoo in Sweden. Varied schedules of enrichment and feeding are used to prevent the animals from knowing when the administration of these events are going to happen since anticipation can lead to a number of negative changes in the behaviours of the animals. Scan sampling was used to gather behavioural data of the animals and the data was then used to answer a number of questions about the extent of success of the varied schedule: 1.Is the varied schedule experienced as unpredictable for the animals? 2. Are there any negative behaviours associated with the scheduled enrichments? 3. What are the reactions to the enrichment being withheld at certain days? The results showed that the animals did not perceive the scheduled events as predictable; pacing in cheetahs and aggressive behaviours in Pallas’s cats seemed to be directly associated with the events; active behaviours in the drills decreased and aggressiveness increased as an immediate result of withholding enrichment. Implications for the animals and the zoo in light of the results are discussed.
22

Sensor augmentation of GPS for position and speed sensing in animal locomotion

Roskilly, Kyle January 2015 (has links)
No description available.
23

Status and distribution of cheetah outside formal conservation areas in the Thabazimbi District, Limpopo province

Wilson, Kelly-Anne 27 February 2007 (has links)
The current status of the cheetah Acinonyx jubatus outside formal conservation areas in South Africa is undetermined. The largest part of the cheetah population in South Africa occurs on cattle and wildlife ranches. Conflict between cheetahs and landowners is common and cheetahs are often persecuted. Cheetah management and conservation efforts are hampered as little data are available on the free-roaming cheetah population. A questionnaire survey was done in the Thabazimbi district of the Limpopo province to collect data on the status and distribution of cheetahs in the district and on the ranching practices and attitudes of landowners. By using this method, a population estimate of 42 – 63 cheetahs was obtained. Camera trapping was done at a scent-marking post to investigate the marking behaviour of cheetahs. Seven different cheetahs were identified marking at one specific tree. Scat analyses were done to determine prey use of the cheetahs in the study area. The most common prey remains from the scats were of the grey duiker Sylvicapra grimmia and the impala Aepyceros melampus. VORTEX analyses were used to investigate the long-term viability of the cheetah population as well as the viability of sport hunting of cheetahs. The current Thabazimbi population is viable over 100 years without immigration, but after 200 years extinction probabilities become unacceptably high. Harvesting through sport hunting is only viable if staggered over several years. Several factors influencing the survival of the free-roaming cheetah population are also discussed. / Dissertation (MSc (Wildlife Management))--University of Pretoria, 2007. / Animal and Wildlife Sciences / unrestricted
24

Cheetah Acinonyx jubatus ecology in the Kruger National Park : a comparison with other studies across the grassland-woodland gradient in African savannas

Broomhall, Lynne Susan 21 November 2005 (has links)
The objectives of this study were(1) to analyse a data-set on cheetah home range size, habitat utilisation, prey selection and hunting behaviour in the Kruger National Park (KNP), and (2) conduct a comparative study on the above aspects of cheetah ecology across a variety of African savanna ecosystems. Cheetah home range sizes in the KNP for territorial male cheetahs were 173 km2, 438 km2 for a nomadic male cheetah coalition, and 193 km2 and 179 km2 for two female cheetahs. Cheetahs preferred open savanna habitat, although females used areas with thicker bush such as drainage lines) more than males, probably because this is the preferred habitat of their main prey. Analysis showed that while females were closely associated with drainage lines, males were closely associated with roads. A male cheetah coalition preferred scent marking along roads rather than in the bush. Impala occurred most frequently in the cheetahs’ diet, although males took larger prey than females. Cheetahs hunted and killed more frequently in open savanna, even though impala densities were higher in adjacent habitats. Mean chase distance for successful hunts was 18l9 m and unsuccessful hunts was 96 m. Cheetah hunting success was 20.7%, kleptoparasitism was 11.8%, mean kill retention time was 165 min, kill rated averaged 1 kill per 4.61 days, and consumption rate of a three-male cheetah coalition was 1,4 kg meat/cheetah/day. Across African savanna ecosystems, female cheetah home range size was determined by the dispersion patterns and biomass of medium-sized prey. Female home range size was larger in areas with migratory (833 km2) than sedentary prey (105 km2) and increase as prey biomass decreased in areas with sedentary prey only. Conversely, male cheetah territory size was smaller in areas with migratory (37 km2) than sedentary prey (108 km2). Although it was predicted that male cheetah territory size would be determined by female cheetah density, no relationship was found here. Across a range of African savannas, cheetahs showed distinct preferences for open habitats that provided some woody cover. Adults (40%) and juveniles (20%) of medium-sized prey made up the largest proportion in the cheetahs’ diet. There were, however, significant variations in the size and age groups of prey taken by cheetahs in different areas. Areas with the least amount of cover appeared to have the longest mean chase distance, and the greatest percentage hunting success and incidents of kleptoparasitism (%). A population viability analysis, using VORTEX, found that cheetah population viability was greater in a woodland savanna than a grassland savanna, particularly at small population sizes. While the grassland savanna population was most affected by changes in juvenile mortality the woodland savanna population with exceptionally high cub mortality may be a sink for cheetahs while the woodland population with lower cub mortality and predicted high dispersal rates may be a source. Maximum annual litter size and female mortality rates had large impacts on population persistence. / Dissertation (MSc (Zoology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted
25

'n Bio-ekologiese en gedragstudie van die jagluiperd Acinonyx jubatus jubatus (Schreber, 1776) (Afrikaans)

Labuschagne, Wilhelmus 06 December 2007 (has links)
Please read the abstract (Uittreksel) in the section, 00front of this document. See also 10summary / Dissertation (MSc (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / MSc / unrestricted
26

The effects of two formulations of deslorelin on the reproduction of male African wild dogs (Lycaon pictus)

Newell-Fugate, Annie Elizabeth 19 February 2009 (has links)
The African wild dog (Lycaon pictus) is the second most endangered carnivore in Africa. Although several high-profile endangered species are imperiled due to poor fertility, inadequate genetic diversity, and a reliance on specific niches, the wild dog is threatened by decreasing land space and human hunting practices. Wild dogs are highly fertile with an average litter size of nine at De Wildt Cheetah and Wildlife Centre. Wild dog males have 3 million to 900 million sperm per ejaculate and 45-75% progressive motility during the breeding season. Wild dogs released into small nature reserves in South Africa experience increased survival rates due to sizeable litters, abundant prey, and increased hunting success along fence lines. Furthermore, the current demand for captive-bred wild dogs is low due to lack of demand by overseas zoos and the inability of nature reserves to accommodate more dogs. Long-acting GnRH analogues have been used for fertility control in many wildlife species. However, dosing and efficacy differ among species and individual animals. This study assessed the efficacy of the GnRH analogue, deslorelin, on reproductive parameters of male African wild dogs. Seasonal effects on reproduction were also evaluated. Captive male African wild dogs housed at the De Wildt Cheetah and Wildlife Centre were administered either a 4.7 mg deslorelin implant (Suprelorin,® Peptech Animal Health (Pty) Ltd, Sydney, Australia; n = 10), an experimental 9.4 mg deslorelin injection (n = 11) or a placebo injection (n = 6). Treatment was administered during the non-breeding season (Month 0), and dogs were assessed at Months 3, 5, 6, and 7. Reproductive parameters evaluated before and after treatment included: serum testosterone, testicular and prostatic volume, and semen quality. Serum testosterone was assessed with a previously validated double antibody DSL testosterone radioimmunoassay kit (Diagnostic Systems Laboratories, Inc, Webster, TX). Testicular volume was calculated from testicular dimensions measured with a calliper and prostatic volume from dimensions obtained by trans-cutaneous ultrasound. Data were analyzed with ANOVA. Although the 4.7 mg deslorelin implant was safe for use in male wild dogs, there was wide variation in efficacy among dogs. The serum testosterone of implant dogs did not decrease to baseline after treatment and only half the dogs administered an implant became azoospermic post-treatment. The experimental long-acting deslorelin injection was ineffective for contraception of male African wild dogs. All three groups of dogs experienced an improvement in reproductive parameters during the months of February through May, the rainy season in northern South Africa and the period during which female African wild dogs enter oestrus, suggesting that a breeding season not only exists in the female African dog but also in the male. Testis and prostatic volume increased, serum testosterone concentrations and semen quality improved during that time of year. Further studies of deslorelin in male wild dogs are warranted to determine the appropriate dose, pay-out pattern, delivery method, and season of delivery necessary for adequate contraception in this species. / Dissertation (MSc)--University of Pretoria, 2008. / Production Animal Studies / unrestricted
27

The re-introduction of captive bred cheetah into a wild environment, Makulu Makete Wildlife Reserve, Limpopo province, South Africa

Maruping, Nkabeng Thato 04 July 2011 (has links)
The conservation benefits of animals in captivity are limited to education and genetic preservation. However, where species or sub-species are critically endangered, the release of captive bred animals into the wild can be used as a strategy to supplement existing populations or to form new founder populations. Cheetahs Acinonyx jubatus born in captivity have no prior experience of survival in wild circumstances. Captive bred cheetahs are currently the greatest source of individuals. This project worked in conjunction with IUCN reintroduction guidelines and pre-existing recommendations in an attempt to develop an ideal methodology of reintroducing captive bred cheetah into the wild. Three captive bred cheetahs, one female and two males, were reintroduced onto Makulu Makete Wildlife Reserve, a predator proofed reserve in the Limpopo province of South Africa, as part of an experimental rehabilitation project. The cheetahs had to lose their homing instinct, be habituated to researchers, become accustomed to eating venison, chewing skin, infrequent large meals and strength development within the three months spent in the enclosures. The cheetahs were habituated to the field researchers on foot and to research vehicles for ease of monitoring. A soft release methodology was used to ease the cheetahs into the environment. Upon release they were tracked twice daily to observe behavior and interaction with their environment. The duration of the project was 20 months which includes enclosure time. The establishment of a home range indicated that the resource need of the cheetahs was satisfied. Eight habitat types were identified in the study area and all cheetahs encompassed part of each in their home range. Though the hunting instinct was present in all the cheetahs, the appropriate hunting techniques and prey selection had to be learned overtime. There was no difference between what was stalked and what was caught. From the observed kills, prey weight ranged from small <40 kg to medium <160 kg. This weight range is comparable to wild cheetahs that select prey within the same range. Each cheetah hunted every four to five days and consumed three to five kilograms of meat per day. Nine prey species were identified, two of which were not detected during direct observations. In the collection of scat, the trained dog found approximately a scat per hour while each direct observation by the researchers took approximately 10 hours. These captive bred cheetahs had to learn how to hunt and how to select appropriate prey thus addressing learned behavior versus instinct. Given the frequency and intensity of injuries sustained and the extensive human influence in the form of veterinary treatment, the reintroduction was not a success. However the techniques developed and modified are relevant for future endeavors‟. / Dissertation (MSc)--University of Pretoria, 2011. / Animal and Wildlife Sciences / unrestricted
28

Carnassial Microwear and Dietary Behaviour in Large Carnivorans

Schubert, B. W., Ungar, P. S., DeSantis, L. R. 01 March 2010 (has links)
This paper presents the first analysis of dental microwear textures of carnivorans. Carnassial microwear is examined for three large carnivorans, the cheetah Acinonyx jubatus, African lion Panthera leo and spotted hyaena Crocuta crocuta using dental microwear texture analysis, which combines confocal microscopy with the study of scale-sensitive fractal geometry. Results indicate significant differences in the microscopic wear textures of these carnivores consistent with dissimilarities in their reported feeding behaviours. Acinonyx jubatus carnassial shearing facets are characterized by low surface texture complexity and high anisotropy, while P. leo and C. crocuta evince less wear texture anisotropy and more complexity. Panthera leo and C. crocuta have more heavily pitted surfaces, a wider size range of wear features and scratches that vary in their orientations relative to the long axis of the carnassial blade. Further, C. crocuta is most variable in overall surface complexity and also has the highest average complexity values. These results are consistent with differences in bone consumption rates among the three species, wherein cheetahs typically avoid bone, lions triturate it on occasion and spotted hyaenas comminute it more often. Incidences of bone consumption in carnivores reflect degree and/or type of carcass utilization and can be used as a general guide for niche partitioning. Thus, the application of microwear analyses to carnivores can be used to interpret competition and niche position within a guild of fossil carnivores across space and through time.
29

Bacterial profiles and antibiograms of the bacteria isolated of the exposed pulps of dog and cheetah canine teeth

Almansa Ruiz, Jose Carlos 14 January 2013 (has links)
Objectives: The aims of this study was to investigate the RC microbiota in CCF canine teeth in the domestic dogs (Canis familiaris) and cheetahs (Acinonyx jubatus), identify the possible factors related to the presence of aerobic or anaerobic bacteria and evaluate and evaluate antibiotic susceptibility of bacteria isolated. Animals: Thirty nine animals suffering from CCF of their canine teeth were included in this study, of which 20 were dogs and 19 were cheetahs. Procedures: Evaluation of the oral cavity of animals while under general anaesthesia was performed and those without necrotic pulps or those that had received antibiotic therapy in the previous two weeks were excluded. Microbial samples were taken from 63 RC of which 27 were from dogs and 36 were from cheetahs. Strict anaerobic and aerobic techniques were used in parallel for plating, incubation and identification of the bacteria isolated in this manner. In an attempt to evaluate the sensitivity of the culture media and anaerobic technique used, additional samples were collected after the samples for bacterial isolation had been taken from the last eight pulps. These comprised those from six cheetahs and two dogs and were analysed using culture techniques and an initial screening with the 16S rRNA-specific PCR. Results: • Dogs: A total of 49 cultivable isolates were recovered belonging to 19 different bacterial species and 13 different genera. Individual RC yielded a maximum of four bacterial species. Of the bacterial isolates, 4.08 % were strict anaerobes, being represented by Clostridium acetobulitycum (2.04 %) and Prevotella melalinogenica (2.04 % ). The incidence of aerobic bacteria and facultative anaerobic bacteria in this study were 18.36 % and 77.56 %respectively of all the bacterial isolates. Of these Pasteurella multocida ( 10.20 % ), Corynebacterium spp. (10.20 %), Moraxella spp. (8.17 %), Bacillus spp. (6.12 %), Aeromonas salmonicida (6.12 %), Escherichia coli (6.12 %) and Pseudomonas aeruginosa (6.12 %) were the bacteria most frequently isolated. In summary, the RC microflora was found to be predominantly Gram negative facultative anaerobic microorganisms. The antibiotic agents that showed the highest efficacy in vitro against the different bacteria isolates were Enrofloxacin (85.21 % ), Gentamicin (92.39 %), Chloramphenicol (89.13 %). • Cheetahs: A total of 59 cultivable isolates, belonging to 19 different microbial species and 13 different genera were recovered from 36 RC sampled. Thirty-two (54.49 %) of the cultivable isolates were Gram positive while 27 (45.71 %) were Gram negative. Individual root canals each yielded a maximum of six species. Four RC had no cultivable bacteria. The bacterial micro flora recovered from the RC of the animals showed a higher number of facultative anaerobes (62.72 % of all the bacterial isolates). Aerobic isolates were 28.81 %, and strict anaerobes 8.47 % of all the isolates. The latter species comprised Clostridium sordelli (5.08 % ), and Clostridium septicum (3.38 % ). The species with the highest isolation frequency were Bacillus spp. (22.13 %), Pasteurella multocida (10.16 %), Corynebacterium spp. (8.47 %), Enterococcus spp. (8.47 %), Moraxella spp. (8.47 %) and Pseudomonas aeruginosa (5.25 %). In summary, the bacteria isolated from the RC were Gram positive facultative anaerobic bacteria. The antibiotics, which showed the highest efficacy in vitro against the different bacteria isolates, were Enrofloxacin (91.96 %), Gentamicin (86.37 %) and Orbifloxacin (86.28 %). • Nucleic Acid-Base detection: In dogs, Gram negative and Gram positive bacterial species were equally represented. Anaerobic bacterial species predominated at 83.3 % (5/6) of the species detected. On the other hand, in cheetahs, the bacterial species isolated by the PCR method showed a prevalence of anaerobic bacteria (60.8 %, 14/23), while facultative anaerobes were isolated in 30.2 % (7 /23) of cases and aerobic bacteria in 8.6 % (2/23). Conclusions and Clinical Relevance: This study has indicated that the microbial flora in any single infected RC is much more diverse than it has been shown using cultural techniques alone and can contain potentially uncultivable bacterial species. Some of these species may represent potentially new phylotypes, which may be involved in endodontic infections and ultimatelyin periradicular periodontitis, and should therefore be considered in any future studies involved in defining endodontic pathogens. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Companion Animal Clinical Studies / restricted
30

Population size, demography and spatial ecology of cheetahs in the Timbavati Private Nature Reserve, South Africa

Dyer, Siobhan Margaret January 2013 (has links)
The cheetah (Acinonyx jubatus) has experienced a drastic decline in numbers over the last 20 years globally and is currently listed as vulnerable by the International Union for the Conservation of Nature (IUCN). In South Africa, there are only an estimated 763 free-ranging cheetahs and conflict with humans is arguably the most significant reason for this low number. The aim of my study was to determine the population size and demographic characteristics of the cheetah population within the Timbavati Private Nature Reserve (TPNR), South Africa, and to contribute to a better understanding of cheetah space use and habitat selection. The research was conducted on TPNR between November 2009 and June 2011 and I used a photographic survey to assess cheetah population size and demographic characteristics. Location data was obtained by collaring two adult male cheetahs with GPS/GSM collars and ad hoc sightings data from across the reserve for an adult female with cubs and three adolescent females. A relatively high minimum population density of 4.46 cheetahs/100km² was estimated, signifying a relatively healthy cheetah population. The sex ratio data indicated a higher male to female ratio and an average litter size of three cubs. The relatively high cub survival rate and density is promising in terms of the status of species within the area, as the data denote the success and potential persistence of the species. Cheetah home ranges varied between 20.97km² for the female with cubs and 659.65km² for the younger collared male. Season did not appear to be a determining factor in terms of home range sizes for the three social groups within the TPNR. However, the males did show a slight increase in their home range sizes during the dry season when resources where presumably more widespread. My results indicate that the cheetah is an adaptable species, flexible in behaviour and able to tolerate a variety of habitat types. Such knowledge is fundamental for planning and implementing the effective management and conservation of cheetahs in South Africa.

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