The role of territoriality was investigated using 25 impala rams in a site in South Africa. Field data were used to determine known rams as territorial and bachelors, as well as aspirant and indeterminate. The mean territorial tenure was 67.25 days, with a mean territory size of 21.0 ± 11.27 ha, compared to the home ranges of 34.1 ha ± 9.03 ha for territorial and 58.8 ha ± 33.35 ha for bachelor males. Territory boundaries seemed to remain constant through the season, and are smaller when bordering important features such as water holes, which appear to be neutral in terms of territoriality. Mating was observed on three separate dates between 16 May - 4 June 2001, three times by territorial males, the exception being an aspirant ram. The most important diurnal behaviour was feeding, followed by watching, walking, ruminating, resting and licking salt. It was found that bachelors browse more than territorial males, and all males browse and lick salt more in the non-rut. All rams were also more vigilant after lions were released. Only bachelors spar and allogroom, and they also orally groom themselves more than territorial males. Territorial males chase and roar more, and perform longer object aggression acts during the non-rut than bachelors. Other behaviours were rare or performed by all rams during the year. / Dissertation (MSc)--University of Pretoria, 2002. / Centre for Veterinary Wildlife Studies / MSc / Unrestricted

Worldwide there is a growing concern of the emergence and evolution of antimicrobial resistance among bacterial pathogens, which poses a threat to human and animal health. The extensive use and misuse of antimicrobials in human and veterinary clinical therapy and agricultural practices have been a major selective force for the emergence, selection, and dissemination of antimicrobial resistant bacteria and resistant genes. Commensal bacteria constitute a reservoir of resistant genes and their level of resistance is considered to be a good indicator for resistance problems to be expected in pathogens. The monitoring of the prevalence of resistance in indicator bacteria such as faecal Escherichia coli and enterococci in different human and animal populations allows the comparison of the prevalence of resistance and to detect transfer between animals and humans and vice versa. Antimicrobial resistance has however, been found in the bacteria of wildlife not exposed to antimicrobials and living in remote areas of this earth. This has implications for resistance control strategies. Previous studies on antimicrobial resistance in wildlife have yielded contrasting results, such as an almost complete absence of resistance in enterobacteria isolated from moose, deer and vole in Finland compared to a high prevalence of resistance in faecal bacteria from wild rodents living in northwest England, which are possibly due to differences in the ecological systems and the proximity to anthropogenic activities. This study further investigates the phenomenon of antimicrobial resistance in wildlife. A previous study conducted in the conservancy area of Kruger National Park (KNP) within South Africa showed that surface water could be a possible source of antimicrobial resistance in unexposed animal populations and that impala (Aepyceros melampus) were good sentinel animals for the documentation of antimicrobial resistance through rivers. This current study followed on this hypothesis and investigated the prevalence of resistance in commensal bacteria isolated from impala and their water sources in KNP. The following four perennial river systems were selected: the Olifants, the Letaba, the Crocodile, the Sabie-Sand Rivers. Samples of river water (n=11) and faeces (n=165) were collected at 11 different sites along these rivers. Samples were directly plated and resistant colonies were selected by means of discs containing antimicrobials (direct plating method). Resistant colonies that grew in the presence of antimicrobials were cultured and identified. Isolates of E. coli (n=12), Enterobacter cloacae (n=49), Pantoea species (n=9), Enterococcus faecalis (n=59), Enterococcus faecium (n=4) and Enterococcus durans (n=64) were tested for susceptibility to a selection of commonly used veterinary antimicrobial drugs. Susceptibility to 18 antimicrobial drugs was determined by means of minimum inhibitory concentrations (MIC) using a commercial MIC test (Sensititre® Bovine/Porcine plate format BOP06F). Our results allow us to give further support to our working hypothesis that antimicrobial resistance, as evidenced in the impala faeces, may have been due to the impala drinking from the polluted rivers, knowing full well that impala are not routinely subjected to any form of antimicrobial treatment. Although the isolates obtained from the water sources were not as many as those obtained from the faecal samples, a degree of resistance was also observed across all the four river systems that we isolated bacteria from, and this was also evident in the faecal samples as well. Our results also further add to the importance of wildlife as sentinels in environmental antimicrobial resistance studies. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Veterinary Tropical Diseases / Unrestricted

The demand for the control of safe food, from consumers the world over, has revolutionized the manner in which wild game meat harvesting occurs. In developed countries, food quality, food and human safety with quality controlling systems embracing environmental carbon footprint issues are constantly improving, for international harmonization at each level of production “from stable to table”, “farm to fork”, “field to yield” as well as from “cradle to grave”. Food industries globally have adopted the in Hazard Analysis Critical control Point (HACCP) system. This is a risk assessment process using Hygiene Assessment Systems (HAS) as a mitigating strategy for risk communication through training. It is also a holistic system that is compatible with international trends designed not only for food safety and quality, but it also embraces other aspects of farming such as animal welfare, environmental management and Occupational Safety and Health. Global marketing for international trade demands quality assurance from trading partners thereby promoting economic growth for developing countries. The watch dog bodies such as the World Trade Organisation (WTO) prohibit trading for non-compliance, therefore trade barriers are in place for uncertified food of animal origin, EU regulations are stringent requirements that need compliance and so too the OIE regulations for disease control, while the Codex Alimentarius Commission maintains trade harmonization. In South Africa Hygiene Assessment Systems (HAS) is a National Hygiene management strategy implemented at abattoirs, that promotes and facilitates quality and hygiene and is reflective of South African quality abroad. It is prescribed under the section, “Essential National Standards” in the Meat Safety Act, 2000, (Act 40 of 2000). This Act covers red meat and includes both domestic animals and game. The Veterinary Procedural Notices (VPN’s) are used for export of game and give far more detailed guidelines than the legislation for game meat sold and consumed locally in South Africa. The objective of the Hygiene Assessment System (HAS) is to create a national awareness of quality to better improve the quality of life of all South Africans, whilst at the same time it is used as an auditing tool for Veterinary Public Health to effectively compare essential standards within the nine provinces. Currently this programme is referred to as the National Abattoir Rating Scheme (NARS), which is only applicable to the high and low throughput Red Meat and Poultry abattoirs in South Africa and not to the Game or Rural abattoirs, thereby further compounding the duality of food standards with food safety being compromised. This study has been undertaken because there are inadequate risk control measures such as introduction of Hazard Analysis Critical Control Point (HACCP) guidelines on primary and secondary meat inspection, specifically on game for local consumption, not only within South Africa, but in the international arena as well. A revision of the HAS document and audit will also be needed to meet with the local (not just export) criteria for wild game harvesting, to enable food safety, thus enabling food security in the remote non - agricultural areas in KwaZulu -Natal. Venison is the meat of today because of health priorities that have arisen over the last ten years. It is low in trans - fatty acids and is regarded internationally as a healthy product produced organically in a free range situation. South Africa has a large potential export market for venison to the European Union because the demand, for venison, exceeds supply in Europe. However, the European Union’s “safe food regulation” that was introduced between 2005 and 2007 with an implementation date of 2008 (Regulation1021/2008) has made it imperative that the HACCP principle is applied to any food or food product of animal origin imported into the European Union or its member states. Also, HACCP specifies that a multidisciplinary team of experts is selected. This then lends itself to a participatory approach to risk assessment as wide consultation is required. This participatory approach was used, including expert opinion surveys and focus group discussions with stakeholders and role-players in the game industry such as commercial hunters, state veterinary services and game ranch owners. Such participants may have better insight into existing conditions than external experts with recognised educational qualifications, usually used in the HACCP team. From this and the relevant Veterinary Procedural Notices for game harvesting, a HACCP process flow and critical control points were derived for the primary phase of meat inspection, including slaughter, primary meat inspection and loading for transport to the abattoir. This was modified during a phase or trial harvesting and then implemented during the harvest of 1758 impala carcasses which were subsequently exported. In addition, environmental risks were considered and a risk mitigation strategy designed, to reduce any possible environmental impacts. In northern Kwazulu Natal, game ranches and conservation areas are in close proximity to the rural poor where food is scarce and comes at a premium price. These game farms harvest seasonally for either the local or export market, hence there is abundance of game offal and by-products available, yet it is at present left in the field or taken to the vulture restaurants (in line with the VPN). Participatory risk analysis was thus also used to investigate the feasibility of using edible offal from impala (Aepyceros melampus) as a source of renewable protein, to address food security issues in impoverished communities in the study area, the districts of uPongola and Jozini, in northern KwaZulu Natal. Structured interviews on the cultural acceptability of impala offal were held with 162 randomly sampled adult respondents in veterinary districts associated with dip tanks. A two stage cluster design was used where the state veterinary areas were stage one and the dip tanks (with proportional random sampling of community members) were the second stage. Offal is a popular food in South Africa in different cultures, called “ithumbu” in IsiZulu, “ boti” by the Indian group, “afval” in Afrikaans and “tripe” in English. Generally demand outstrips supply of offal at red meat abattoirs in South Africa. It was found that there was no significant difference between those who would eat impala offal and those who would eat the offal of sheep. It was concluded that it is feasible to use inspected game offal from impala as a protein source in much the same way as red meat offal is used and that the current practice of leaving the offal for predators was likely, if it continues, to cause imbalances in the predator/ prey ratio on game farms. It is recommended that the VPN for game be amended to encompass inspected offal being allowed into the formal food chain, in line with the standard operating procedure developed during this study. Also that current fragmentation of legislation and the implementation thereof is revisited for effective control for harmonisation of food safety standards for game meat within South Africa. / Dissertation (MMedVet)--University of Pretoria, 2012. / Paraclinical Sciences / unrestricted

A case control study was performed in the conservancy area of the Kruger National Park (KNP), South Africa to find out whether the faeces of impala (Aepyceros melampus) were more likely to contain tetracycline resistant Escherichia coli (TREC) when they drank from rivers that contained these bacteria, compared to rivers that were uncontaminated with TREC. Five perennial rivers (Crocodile, Letaba, Olifants, Sabie and Sand) were selected. A total of 11 points in these rivers were sampled on three separate occasions and cultured for E. coli. Impala herds within 5 kilometres of each water collection site were identified and between 5 and 10 fresh faeces were collected for each collection period (n=209 faecal specimens). Selective culturing of E. coli was done and the resulting colonies were screened for tetracycline resistance by using the Lederberg Replica Plating (LRP) method. Resistant colonies were those that grew in the presence of 4 mg/L of tetracycline. Both a resistant and/or a susceptible isolate were then selected from each specimen, and subjected to the minimum inhibitory concentration (MIC) micro-broth dilution test for tetracyclines. The breakpoint for the MIC method was considered ≥ 8 mg/L (which is higher than for the LRP method). Twenty one of the 33 water specimens examined were found to be contaminated by E. coli. Among them (n=21), 76.19% (n=16) were resistant to tetracycline using the LRP method, although using the MIC method only 19.05% (n=4) were resistant. All of the resistant strains originated from the Letaba, Olifants and Crocodile rivers (TRECpos rivers). Among the 209 impala faeces sampled, 191 were positive for the presence of E. coli (91.38%). Within these (n=191), 36.64% (n=70) showed TREC using the RPL method, while using the MIC, 9.95% (n=19) were found to be TREC. The RPL and MIC methods showed a concordance of only 48%. Resistant isolates screened by PCR for tet(A) and tet(B) genes were found to be negative and it was concluded that other resistant genes were responsible. The odds ratios (OR) showed that impala drinking from TRECpos rivers were 19.3 (2. 63-141.68) times more likely to be infected with TREC than unexposed impala / Dissertation (MSc)--University of Pretoria, 2007. / Paraclinical Sciences / unrestricted

農林水産研究情報センターで作成したPDFファイルを使用している。

Please read the abstract in the section 08summary of this document / Thesis (PhD (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted

Habitat loss and fragmentation is a crisis affecting wildlife worldwide. In Tanzania, East Africa, a dramatic and recent (<80 years) expansion in human settlement and agriculture threatens to reduce gene flow among protected areas for many species of large mammals. Wildlife linkages can mitigate population isolation, but linkage designs lacking empirical justification may be controversial and ineffective. Connectivity conservation requires an understanding of how biogeographic factors shaped gene flow prior to habitat loss or fragmentation, however the history of interaction among populations is rarely known. The goal of my study was to provide context for connectivity conservation in central and southern Tanzania by identifying landscape features that have shaped gene flow for three ungulate species with different dispersal capabilities. I investigated historical patterns of connectivity for Maasai giraffe (Giraffa camelopardalis tippelskirchi), impala (Aepyceros melampus), and eland (Tragelaphus oryx) by estimating genetic structure among four to eight protected areas per species. Genetic structure changes very slowly among large populations and thus is likely to reflect historical processes instead of recent anthropogenic influences. I collected noninvasive DNA samples and generated microsatellite genotypes at 8 to 15 loci per species, then estimated genetic diversity metrics (allelic richness, AR, and expected heterozygosity, H[subscript E]) for each population (defined by reserve). I also calculated genetic distance (F[subscript ST] and Nei's unbiased genetic distance, D[subscript hat]) and an estimate of gene flow (Nm) between all population pairs for each species. To elucidate the possible causes of genetic structure between these populations, I tested for isolation by distance and isolation by resistance based on a suite of biogeographic factors hypothesized to affect gene flow. To do this, I created GIS-based resistance surfaces that assigned different costs of movement to landscape features. I created one or more resistance surfaces for each hypothesis of landscape effect. I used circuit theory to estimate the cumulative resistance between each pair of reserves for each weighting scheme, and then performed Mantel tests to calculate the correlation between these resistances and the observed population pairwise genetic distances (D[subscript hat]). I chose the optimal resistance model for each species as the model that was most highly correlated with observed genetic patterns. To verify that the correlation of resistance models with genetic distance was not an artefact of geographic distance, I performed partial Mantel tests to calculate correlation while controlling for the effect of geographic distance. Finally, I compared historical gene flow patterns to the distribution of contemporary human activity to predict areas that are at risk of a loss of connectivity. Indices of genetic diversity were moderate for all three species and comparable to previously reported values for other savannah ungulates. Diversity (both H[subscript E] and A[subscript R]) was highest in eland and lowest in giraffe for these populations, and was not consistently correlated with reserve size as has been reported for other species in East Africa. Although patterns in genetic distance were broadly similar across all three species there were also striking differences in connectivity, highlighting the importance of cross-species comparisons in connectivity conservation. At this scale, resistance models based on slope strongly predicted population structure for all three species; distance to water was also highly correlated with genetic distance in eland. For all three species, the greatest genetic distances occurred between populations separated by the Eastern Arc Mountains, suggesting that the topography of this area has long acted as a barrier to gene flow, but this effect is present in varying degrees for each species. I observed high levels of historical gene flow between centrally located populations (Ruaha National Park and Rungwa Game Reserve) and those in the southwest (Katavi National Park and Rukwa Game Reserve). Although human settlement in this area has been low relative to other areas, the connection between the Katavi/Rukwa and Ruaha ecosystems may be threatened by increased human activity and warrants conservation. High levels of historical gene flow were also seen between reserves in the northeast (Tarangire National Park, Swagaswaga Game Reserve) and the central and southwest populations. These connections appear highly threatened due to current land use practices, and may have already suffered a loss of gene flow. Field surveys in the lands surrounding the northeastern reserves are needed to quantify current levels of connectivity and determine whether corridors could be established to maintain or restore gene flow with other reserves. / Graduation date: 2012

The effect of cattle grazing on the abundance and distribution of vegetation, burrowing crabs (Uca rapax, Uca pugnax, and Sesarma cinereum), marsh periwinkles (Littoraria irrorata), horn snails (Cerithidea pliculosa), and salt marsh snails (Melampus bidentatus) was evaluated over four seasons (summer 2000, fall 2000, winter 2001, and spring 2001) in grazed and ungrazed treatments. A Galveston Island salt marsh adjacent to Snake Island Cove was sampled at five elevations, from the water's edge to the high tidal flats. Data were analyzed for statistical differences using a two-way ANOVA in SAS. Cattle grazing may affect the vegetation and macroinvertebrate communities in salt marshes through trampling and herbivory. Vegetation resources available to other herbivores are decreased by the direct consumption of plant material by cattle. Spartina alterniflora and Salicornia virginica heights were significantly greater in ungrazed treatments than grazed for every season in the edge, upper, and middle elevation zones. Total aerial vegetative cover was also reduced significantly in grazed treatments, with the greatest impact in the edge and upper marsh. In the ungrazed treatments, S. alterniflora stem density was significantly greater in edge elevations, while both S. virginica percent cover and stem density in the edge elevation was greater. Burrowing crab populations were greater in the upper marsh and edge habitat of ungrazed treatments, while significantly greater in most of the middle marsh habitats of the grazed treatment. Size of burrowing crabs was generally significantly greater in ungrazed treatments. Cerithidea pliculosa size decreased in grazed treatments, but population had an overall increase in grazed treatments. Littoraria irrorata had very few differences between treatments, although few specimens were found. Melampus bidentatus populations were too small to evaluate thoroughly. Macroinvertebrate populations could be used to assess the overall health of grazed salt marshes.

The effect of cattle grazing on the abundance and distribution of vegetation, burrowing crabs (Uca rapax, Uca pugnax, and Sesarma cinereum), marsh periwinkles (Littoraria irrorata), horn snails (Cerithidea pliculosa), and salt marsh snails (Melampus bidentatus) was evaluated over four seasons (summer 2000, fall 2000, winter 2001, and spring 2001) in grazed and ungrazed treatments. A Galveston Island salt marsh adjacent to Snake Island Cove was sampled at five elevations, from the water's edge to the high tidal flats. Data were analyzed for statistical differences using a two-way ANOVA in SAS. Cattle grazing may affect the vegetation and macroinvertebrate communities in salt marshes through trampling and herbivory. Vegetation resources available to other herbivores are decreased by the direct consumption of plant material by cattle. Spartina alterniflora and Salicornia virginica heights were significantly greater in ungrazed treatments than grazed for every season in the edge, upper, and middle elevation zones. Total aerial vegetative cover was also reduced significantly in grazed treatments, with the greatest impact in the edge and upper marsh. In the ungrazed treatments, S. alterniflora stem density was significantly greater in edge elevations, while both S. virginica percent cover and stem density in the edge elevation was greater. Burrowing crab populations were greater in the upper marsh and edge habitat of ungrazed treatments, while significantly greater in most of the middle marsh habitats of the grazed treatment. Size of burrowing crabs was generally significantly greater in ungrazed treatments. Cerithidea pliculosa size decreased in grazed treatments, but population had an overall increase in grazed treatments. Littoraria irrorata had very few differences between treatments, although few specimens were found. Melampus bidentatus populations were too small to evaluate thoroughly. Macroinvertebrate populations could be used to assess the overall health of grazed salt marshes.