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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

Scatology as non-invasive tool for conservation of cheetah (Acinonyx jubatus Von Schreber, 1775) in South Africa

Herring, Kiersten Sarah 12 June 2009 (has links)
Cheetah are difficult to census and as a result there is only a limited amount of information regarding the status of cheetah populations across South Africa making it difficult to identify and address potential threats and to plan effective conservation strategies. The aim of this study was to determine if scatology could be used as a non-invasive method for genetic analysis of cheetah in South Africa. Corresponding blood and faecal samples were collected from cheetah at the De Wildt Cheetah Centre. The faecal samples were aged and then collected and stored in ethanol after four days and after two weeks. Faecal samples of suspected wild cheetah were also collected in the Thabazimbi area in the Limpopo Province. DNA was than isolated from all the blood and faecal samples. A species-specific primer set was developed in the mitochondrial control region to reliably identify cheetah faecal samples. The PCR amplification success of the species-specific marker was high, all fresh faecal samples had a positive result (100%), four-day-old samples were 83% positive and two-week-old samples were 94% positive. The species-specific primer was found to be effective in accurate cheetah identification and had greater amplification success on fresh samples. Twelve microsatellite markers were used to profile the blood and faecal samples. Multiple PCRs were performed per faecal sample per marker to ensure that the genotype obtained was correct. Amplification success of the 12 microsatellites was 59% for fresh samples, 20% for four-day-old samples and 2.4% for two-week-old samples. Difficulties associated with the technique included poor DNA quality and quantity and genotyping errors, resulting in allelic dropout and false alleles. Genotyping errors were determined by comparing the genotype of the faeces with that of the matching blood sample. Overall, allelic dropout experienced was 16% and 7% for false alleles. These values correspond to the results of similar studies. Samples of suspected wild cheetah were collected in the Thabazimbi area and were analysed. The alleles obtained were similar to those from the pilot study. Data of 45 De Wildt cheetah samples obtained from the NZG were analysed and compared with the results of the pilot study, as expected, all alleles in the De Wildt population occurred in the NZG samples. The alleles found in this study and in the NZG samples can be used as the standard when using molecular scatology techniques. The results of this study provide valuable guidelines for future studies of cheetah using the non-invasive technique of scatology. The genotypic information from the 12 microsatellites can now be used as a standard when analyzing samples of cheetah origin. Using this information, additional markers can now be tested for improved amplification success and decreased rates of allelic dropout and occurrences of false alleles. The results prove the feasibility of using cheetah faeces as a potential source of DNA for population studies of cheetah in South Africa in addition to the methods currently employed. / Dissertation (MSc)--University of Pretoria, 2010. / Animal and Wildlife Sciences / unrestricted
2

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

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