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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

Molecular phylogeography and evolutionary history of the greater kudu (Tragelaphus strepsiceros)

Sakwa, James Shikuku 24 November 2005 (has links)
The greater kudu (Tragelaphus strepsiceros) is a large spiral-horned antelope that occurs in sub-Saharan Africa. The species is predominantly a browser and inhabits a diverse range of habitats including savanna woodland, scrub and open forests. The geographical distribution extends from south-eastern Chad, northern Central African Republic (CAR), through eastern Africa, to southern Africa. Throughout its range the species is threatened by habitat loss, fragmentation, diseases and hunting for trophy. Consequently, many populations have reduced numbers and are at great risk of local extinction. In the absence of evidence from comprehensive studies, strategies for conservation and management of many species are often based on subspecies designations despite the fact that the original descriptions were based on few samples and morphological characters that vary extensively. To develop appropriate conservation and management measures, it is imperative to obtain information on population structure, historical demography and evolutionary history of the species. The information generated is used to define units for conservation of the species. In this study, the objective was to investigate population structure and evolutionary history of the greater kudu by analysing mitochondrial DNA (mtDNA) control region sequences and examining size variation in eight microsatellite loci. The mtDNA control region sequences were examined using a combined approach that included phylogeographic, nested clade and mismatch frequency distribution analyses. It was anticipated that use of the two types of genetic markers with contrasting patterns of inheritance and mutation would enhance the understanding and interpretation of the evolutionary history of the species throughout its range. The results were used to evaluate subspecies taxonomy, draw inferences on historical demography and provide information relevant for conservation and management of T. strepsiceros. Intraspecific variation in the mtDNA was examined in 94 samples from 12 locations and revealed low to medium levels of nucleotide diversity. The average nucleotide diversity was 2.7% (0.3% to 2.9%). The average sequence divergence between populations was 2.3% (0.0% to 5.7%). Eight microsatellite loci were analysed in 203 samples representing 13 locations. The number of alleles scored from these loci was 7-12 while the mean heterozygosity was 70.4% (66% to 76%). Microsatellite data showed shallow phylogeographic structure and the average measure of genetic differentiation <1>ST was 0.046. Comparisons of allelic variation across all populations revealed that the Eastern Cape had lower allelic diversity and showed significant differences in allele frequency distribution suggesting a genetic bottleneck in the population's evolutionary past. The combined analyses suggest that the greater kudu originated from Namibia and spread southwards before colonising other parts of its modern range. The results revealed weak geographic partitioning at the regional level, but showed two genetically distinct groups at the continental level. The first group comprised of populations from Namibia, Kimberley and the Eastern Cape from South Africa, while the second comprised of the remaining populations. The results suggest a single evolutionary significant unit (ESU) with two management units (MUs). In the long term, conservation efforts should focus on maintaining demographic connectivity over broad geographical areas within each MU in order to approximate the natural dispersal patterns of the species. / Thesis (PhD (Zoology))--University of Pretoria, 2005. / Zoology and Entomology / unrestricted
2

The social and spatial organisation of the Greater kudu (Tragelaphus strepsiceros Pallas 1766) in the Andries Vosloo Kudu Reserve, Eastern Cape

Allen-Rowlandson, T S January 1981 (has links)
Methods of capture, marking and age determination in the field, were investigated. The density and structure of the population, individual movements and social relationships were determined. Aspects of reproduction examined included age at puberty, agespecific fecundity, calving intervals and seasonality. Temporal changes in the spatial and social organisation are discussed in relation to environmental conditions, reproduction and population structure. Factors influencing the fecundity, dynamics and grouping patterns within the population are considered.
3

The prevalence of helminths in warthogs, bushpigs and some antelope species in Limpopo Province, South Africa

Conradie, Ilana 17 February 2009 (has links)
The aim of the study was to describe the helminth parasites of the common game species in the Limpopo Province, focusing on the northern and western parts where the climate is harsh and dry, with a large area considered to be semi-arid. In total 36 animals were examined which included ten impala, Aepyceros melampus, eight kudu, Tragelaphus strepsiceros, four blue wildebeest, Connochaetes taurinus, two black wildebeest, Connochaetes gnou, three gemsbok, Oryx gazelle, one nyala, Tragelaphus angasii, one bushbuck, Tragelaphus scriptus and one waterbuck, Kobus ellipsiprymnus, as well as six warthogs, Phacochoerus aethiopicus, and a single bushpig, Potamochoerus porcus. New host records for species include Trichostrongylus deflexus in the blue wildebeest, Agriostomum gorgonis in the black wildebeest, Stilesia globipunctata in the waterbuck, and Fasciola hepatica in the kudu. The only known zoonotic helminth recovered was one hydatid cyst of an Echinococcus sp. from the lungs of a warthog. The total burdens and species variation of the helminths in this study were all consistently low compared to other studies done in areas with higher rainfall. This has practical implications when animals are translocated to areas with higher rainfall and higher prevalence of helminths. / Dissertation (MSc)--University of Pretoria, 2008. / Veterinary Tropical Diseases / unrestricted
4

Meat quality of kudu (Tragelaphus strepsiceros) and impala (Aepyceros melampus)

Mostert, Analene C. 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: Although kudu (Tragelaphus strepsiceros) and impala (Aepyceros melampus) are found in the same geographical area, there is variation in their diets as kudu are predominantly browsers, feeding on tree and shrub leaves, while impala are known as mixed feeders as they graze and browse. Therefore this poses the question whether the diet would influence their meat quality. The objective of this investigation was to evaluate the physical measurements and chemical composition of M. longissimus dorsi, M. biceps femoris, M. semimembranosus, M. semitendinosus and M. supraspinatus for kudu and impala, two southern African antelope species. The effects of age (adult and sub-adult) and gender (male and female) were also determined. The sensory characteristics of the M. longissimus dorsi muscle for sub-adult kudu and impala were investigated. Correlations between the various physical measurements and chemical composition of the meat were verified. Physical measurements and chemical composition of the M. longissimus dorsi muscle were tested for correlations with the sensory ratings of the meat. Dressing percentage of impala (59.88%) (n=28) was higher than that of kudu (57.60%) (n=35). The main effects (species, gender and age) showed no differences for drip loss and cooking loss. However, muscles differed in terms of cooking loss with impala M. semitendinosus having the highest (38.28%) value and kudu M. longissimus dorsi having the lowest value (30.77%). For impala, the highest Warner–Bratzler shear (WBS) values were measured for M. semimembranosus (5.90 kg/1.27cmø), followed by M. biceps femoris, M. longissimus dorsi, and M. semitendinosus with the lowest WBS values measured for M. supraspinatus (3.61 kg/1.27cmø). All impala muscles had lower L* values and appeared darker in colour than kudu muscles, except for M. supraspinatus. Adult animals also had lower L* values than the sub-adult group. Kudu had significantly higher a* and b* values (more red) than impala. Chroma values were higher for kudu, thus appearing brighter in colour. The respective muscles of kudu and impala investigated differed significantly in terms of physical characteristics. However, gender and age did not have an effect on the physical measurements. Moisture content was higher in kudu meat (76.46%) than in impala meat (75.28%). Muscles differed for both moisture and fat content. The highest fat was found in M. supraspinatus followed by M. biceps femoris, M. semitendinosus, M. semimembranosus and M. longissimus dorsi. Protein content did not differ between species (kudu: 21.66%; impala: 22.26%), gender (male: 21.98%; female: 21.95%) and age groups (adult: 21.74%; sub-adult: 22.18%). Kudu M. longissimus dorsi (1.62%) had lower fat content than impala M. longissimus dorsi (2.22%) and female animals had a higher fat content than male animals. Sub-adults (1.20 ± 0.02%) had higher ash content than adults (1.10 ± 0.03%). The M. supraspinatus had the lowest protein and also the highest fat content, with M. semimembranosus having the lowest fat content but the highest value for protein. Myoglobin content did not differ between species, although females had higher (6.58 ± 0.20 mg/g) myoglobin content than males (5.11 ± 0.25 mg/g). Glycolitic muscles had the lowest myoglobin content with the highest values found in M. supraspinatus, an oxidative muscle. An interaction was noted between species and muscle for myoglobin content. Myoglobin content in impala M. longissimus dorsi was higher than that in kudu M. longissimus dorsi; however for all other muscles the myoglobin content was lower in impala. Gender did not affect mineral content. Potassium levels were highest for kudu while phosphorus was more prevalent in impala meat. Adult and sub-adult groups differed in terms of potassium, calcium and zinc content. Potassium and calcium content were higher for subadult animals while zinc content was higher in adult animals. In impala meat, stearic acid (22.67%) was the major fatty acid, followed by palmitic acid (16.66%). In contrast, oleic acid (24.35%) was the most profuse fatty acid in kudu, followed by linoleic acid (22.95%). The SFA’s as a percentage of the total fatty acids differed between impala (51.12%) and kudu meat (34.87%). Kudu meat had a higher concentration of total PUFA (38.88%) than impala (34.06%) meat. The PUFA: SFA ratio for kudu meat (1.22) was more favourable than that for impala meat (0.73). The ratio of n-6 PUFA’s to n-3 PUFA’s for kudu and impala were determined as 2.22 and 3.76 respectively. From the current findings it is evident that kudu and impala meat have advantageous fatty acid profiles and can be a healthy substitute for other red meats. Kudu meat (72.62 ± 1.86 mg/100g) had higher cholesterol than impala meat (55.35 ± 1.84 mg/100g). It is recommended that further studies be done in order to confirm the cholesterol content of kudu meat. Within species, no gender differences for any of the sensory characteristics tested were noted. The impala meat had a more intense game aroma than the kudu meat, while kudu meat was found to be more juicy than impala meat. It can therefore be concluded that the marketing of game meat should be species-specific as there are distinct flavour and aroma differences between kudu and impala meat. / AFRIKAANSE OPSOMMING: Alhoewel koedoes (Tragelaphus strepsiceros) en rooibokke (Aepyceros melampus) in dieselfde geografiese area voorkom, is daar variasie in hulle diëte. Koedoes is hoofsaaklik blaarvreters, terwyl rooibokke bekend staan as gemengde vreters aangesien hulle grassowel as blaarvreters is. Die vraag ontstaan dus of die verskil in diëet die kwaliteit van hulle vleis sal beϊnvloed. Die doel van hierdie ondersoek was dus om die fisiese metings en chemiese samestelling van die M. longissimus dorsi, M. biceps femoris, M. semimembranosus, M. semitendinosus en M. supraspinatus vir koedoes en rooibokke te bepaal. Die invloed van ouderdom (volwasse en onvolwasse) en geslag (manlik en vroulik) op hierdie eienskappe is ook geëvalueer. Die sensoriese eienskappe van die M. longissimus dorsi van onvolwasse koedoes en rooibokke is ook ondersoek. Korrelasies tussen die fisiese metings en chemiese samestelling van die vleis is ondersoek. Die fisiese metings en chemiese samestelling van die M. longissimus dorsi is getoets vir korrelasies met die resultate van die sintuiglike evaluering van die vleis. Die gemiddelde uitslagpersentasie van rooibokke (59.88%) (n=28) was hoër as die van koedoes (57.60%) (n=35). Daar was geen verskille in drupverlies en kookverlies vir die hoofeffekte (spesie, geslag en ouderdom) nie. Spiere het wel verskil in terme van kookverlies, met die hoogste waarde gemeet vir rooibok M. semitendinosus (38.28%) en die laagste waarde vir koedoe M. longissimus dorsi (30.77%). In rooibokke was die hoogste Warner- Bratzler skeurkrag waardes gemeet vir M. semimembranosus (5.76 kg/1.27cmø), gevolg deur M. biceps femoris, M. longissimus dorsi, en M. semitendinosus met die laagste Warner- Bratzler skeurkrag waardes gemeet vir M. supraspinatus (3.78 kg/1.27cmø). Alle rooibokspiere het laer L* waardes gehad en was donkerder van kleur as koedoespiere, behalwe vir M. supraspinatus. Laer L* waardes is ook verkry vir volwasse diere in vergelyking met onvolwasse diere. Die a* en b* waardes was hoër in koedoe- as in rooibokvleis, m.a.w. koedoevleis het rooier vertoon. Die onderskeie koedoe- en rooibokspiere het betekenisvol verskil in terme van fisiese eienskappe, terwyl geslag en ouderdom geen effek op die fisiese eienskappe gehad het nie. Voginhoud was hoër in koedoe- (75.52%) as in rooibokvleis (74.52%). Verkille tussen spiere is opgemerk vir beide vog- en vetinhoud. M. supraspinatus het die hoogste vetinhoud gehad, gevolg deur M. biceps femoris, M. semitendinosus, M. semimembranosus en M. longissimus dorsi. Geen verskille is opgemerk tussen spesies (koedoe: 21.66%; rooibok: 22.26%), geslagte (manlik: 21.98%; vroulik: 21.95%) en ouderdomme (volwasse: 21.74%; onvolwasse: 22.18%) in terme van proteϊeninhoud nie. Die vetinhoud van koedoe M. longissimus dorsi (1.62%) was laer as dié van rooibok M. longissimus dorsi (2.22%) en die vetinhoud van vroulike diere was hoër as dié van manlike diere. Onvolwasse diere (1.20 ± 0.02%) het ‘n hoër asinhoud as dié van volwasse diere (1.10 ± 0.03%) getoon. In terme van die onderskeie spiere het M. supraspinatus die laagste proteϊen- en die hoogste vetinhoud gehad, terwyl M. semimembranosus die laagste vet- en die hoogste proteϊeninhoud gehad het. Die mioglobieninhoud was nie beϊnvloed deur spesie nie, terwyl vroulike diere ‘n hoër (6.58 ± 0.20 mg/g) mioglobieninhoud as manlike diere (5.11 ± 0.25 mg/g) gehad het. Die M. supraspinatus, ‘n oksidatiewe spier het die hoogste mioglobieninhoud gehad, terwyl glikolitiese spiere die laagste mioglobieninhoud gehad het. ’n Interaksie tussen spesie en spier was opgemerk vir mioglobieninhoud. Rooibok M. longissimus dorsi het ‘n hoër mioglobieninhoud as koedoe M. longissimus dorsi gehad, terwyl die mioglobieninhoud vir al die ander spiere laer was in rooibokke. Mineraalinhoud was nie deur geslag beϊnvloed nie. Kaliumvlakke was hoër in koedoevleis, terwyl fosforvlakke hoër was in rooibokvleis. Kalium- en kalsiuminhoud was hoër in onvolwasse diere terwyl die sinkinhoud hoër was in volwasse diere. Steariensuur (22.67%), gevolg deur palmitiensuur (16.66%) was die mees algemene vetsure in rooibokvleis. In teenstelling hiermee was oleϊensuur (24.35%), gevolg deur linoleϊensuur (22.95%) die mees algemene vetsure in koedoevleis. Die totale versadigde vetsure was laer in koedoevleis (34.87%) in vergelyking met rooibokvleis (51.12%), terwyl die totale polionversadigde vetsure in koedoevleis (38.88%) hoër was as dié van rooibokvleis (34.06%). Die verhouding van n-6 tot n-3 poli-onversadigde vetsure vir koedoe en rooibok was 2.22 en 3.76 onderskeidelik. Hierdie resultate bevestig dat koedoe- en rooibokvleis oor ‘n vetsuurprofiel beskik wat ’n gesonde alternatief bied tot ander rooivleise. Die cholesterolinhoud van koedoevleis (72.62 ± 1.86 mg/100g) was hoër as dié van rooibokvleis (55.35 ± 1.84 mg/100g). Dit word egter aanbeveel dat verdere studies gedoen word om die cholesterolinhoud van koedoevleis te bevestig. Binne spesies was daar geen geslagsverkille vir enige van die sensoriese eienskappe nie. Rooibokvleis het ‘n meer intense wildsvleis aroma as koedoevleis gehad, terwyl koedoevleis meer sappig was as rooibokvleis. Hierdie resultate dui daarop dat die bemarking van wildsvleis spesie-spesifiiek moet wees aangesien daar defnitiewe geur en aroma verskille tussen koedoe- en rooibokvleis is.
5

The role of small antelope in ecosystem functioning in the Matobo Hills, Zimbabwe

Lunt, Nicola January 2011 (has links)
The 28-month study assessed the impacts of five syntopic medium-sized mammalian browsers and one fire event in a woodland savanna in the Matobo Hills, Zimbabwe. Aspects of herbivory, mechanical pressures, seed dispersal and nutrient cycling were investigated for three species of small antelope (common duiker [Sylvicapra grimmia]1, klipspringer [Oreotragus oreotragus] and steenbok [Raphicerus campestris]) and two medium-sized species (bushbuck [Tragelaphus scriptus] and greater kudu [T. strepsiceros]). Focusing on Burkea africana2 woodland, in a system that does not include elephant (Loxodonta africana), effects of browsing antelope on woody and herbaceous vegetation development were investigated using exclusion plots. Browsers regulated woody plant cover (measured as basal stem area), with smaller antelope having a greater impact than larger species. This was linked to feeding height, feeding selectivity and mechanical pressures (e.g. twig breakage and trampling). Fire caused an initial reduction in above-ground standing biomass, but in the presence of fauna, pre-fire equilibria were attained within 15 months. In antelope exclosures, herbaceous biomass increased and woody biomass decreased following fire. Responses by woody vegetation to browsing varied among species, with highly palatable species typically exhibiting compensatory regrowth. Woody species richness and abundance (especially of palatable species) increased in the absence of browsers, but species richness of the herbaceous layer was promoted by moderate disturbance (trampling or fire). Faecal deposition behaviour, primarily the use of latrines by small antelope, resulted in localised soil enrichment within defended territories. Decomposition rates (and therefore return of nutrients to the soil) varied among species and seasons, due to defecation site selection, accessibility to decomposers and desiccation rates of faecal pellets. Controlled seed germination experiments indicated that ingestion by small antelope enhances germination rates of large, hard-seeded fruits such as Sclerocarya birrea. However, germination of savanna seeds may require multiple cues. This study demonstrated the critical roles of small antelope in ecosystem functioning, and highlights the importance of the less visible impacts of frequently overlooked smaller mammalian herbivores. Perturbations to the faunal community, especially small antelope, are predicted to have substantial impacts on woody plant cover.

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