Achieving environmental s¬ustainability in human organization is the defining challenge of the modern era. In light of the inability of the existing economic paradigm to provide for sustainability objectives, novel approaches to understanding and managing economic activities are required. Towards this end, the emergent field of ecological economics provides an alternative paradigm that expressly prioritizes the development of the theory and tools necessary to operationalize environmental sustainability in economic activity, which is viewed as prerequisite to sustainability in any other sphere. Here, I advance an internally consistent framework for understanding and implementing the core ecological economic sustainability criteria: appropriate scale relative to biocapacity; distributive justice; and efficient allocation. This framework includes: (1) an ecological communitarian conception of distributive justice which recognizes environmental sustainability as the first principle of distributive justice; (2) the rationale for biophysically-consistent ecological economic modeling of human activities as a basis for environmentally-enlightened policy and management; and (3) an appeal for scale-oriented environmental governance as could potentially be operationalized by a strong, centralized World Environment Organization. I further apply this framework to evaluating the current and future status of livestock production systems at regional and global scales with respect to efficiency considerations as well as their relationships to sustainability boundary conditions for human activities as a whole. It is suggested that the current and projected scale of the livestock sector is fundamentally unsustainable, and that all leverage points must be exploited to rein in this sector in the interest of preventing irreversible ecological change. This must include, but cannot be limited to, strong eco-efficiency measures and changes in production technologies, species substitutions, and consumption patterns and volumes. Outcomes are interpreted in terms of their implications for environmental policy and governance oriented towards the sustainability objective.

A wireless electronic nose network system has been developed for monitoring and analyzing livestock farm odour. The system utilizes electronic noses (e-noses) that can measure odour compounds and environment factors such as temperature and humidity. The e-noses are deployed at various locations on the farm, and sensor signals are transmitted via a wireless communication to a central station, where the data processing and sensor fusion algorithms analyze the collected odour data, compute the odour concentration, and display the odour dispersion plume. This system would provide users with convenient odour monitoring capabilities and help the development of an effective overall odour management strategy. In addition, an adaptive neuro-fuzzy inference approach is proposed to calibrate the e-nose responses to human panelists' perception. The proposed method can handle non-numeric information and human expert knowledge in livestock farm odour models, and can adjust the parameters in a systematic manner for optimal system performance. The proposed approach has been tested against a livestock farm odour database. Several livestock farm odour models have been developed for comparative studies. The results show that the proposed approach provides a more accurate odour prediction than a typical multi-layer feedforward neural network. Furthermore, to model odour dispersion around livestock facilities, a biologically inspired odour dispersion model is proposed, and is tested using computer simulations and a livestock farm odour database. Results show that the proposed approach is effective in providing accurate modelling of odour dispersion from multiple and various types of odour sources in both static and non-static environments.

For the nearly 70% of India’s population of 1.2 billion who reside in rural villages, agriculture is often the primary source of income, as well as of food, fodder and fuel. Rural agricultural systems are recognized as complex mixed-cropping-livestock systems, whereby primary and secondary products from one component of the system are used in another. For instance, primary products such as grain and milk from livestock can be used for human consumption, while secondary products such as crop residues can be used as fodder or fuel, while manure finds use as fertilizer. Variations in cropping pattern and intensity will determine the production potential of food, fodder and fuel within a region. As limiting factors, land area and yield must also be considered in agricultural planning activities. The present research aims to develop a rational method for crop selection within a particular agro-ecoregion. An optimization model is constructed to optimize for selected parameters that are set to maintain defined basic minimum standards for human nutritional and livestock fodder demands. An agricultural survey was carried out in 2007 for three villages in Karnataka State, India. All three villages were located within the dryland agro-ecozone, where crop yields are relatively low. The survey was stratified according to household landholding area ranging from marginal (0-1 ha) to large (>4 ha). Information was solicited on the demographic indicators of the population, the cropping cycle and cropping varieties used within the regions, and certain livestock parameters were gathered. Various demands, such as human food energy and protein requirements as well as fodder, and constraints, such as land area, were modeled to determine the potential for food, fodder and fuel production under optimal cropping pattern. The linear programming software, What’sBest, Version 9.0 from LINDO systems, was used to solve the optimization model. Results indicate that the current export-driven cropping pattern produces inadequate food to satisfy human nutritional demands at the village level, particularly among marginal and small households, who produce in the range of only 10 and 50 % of required food energy and protein, respectively, on a household basis. The current cropping pattern is also inadequate to satisfy village-wide livestock fodder demand, especially in villages heavily centered on cash crops,wherein only 30-40 % of fodder demand can be accounted for. On an individual household level, it is determined that a minimum 0.8 ha of land area is required to satisfy both food and fodder demands, placing strain on marginal households, who own less then 1 ha of land. The optimization model also demonstrates that it is possible to produce adequate food and fodder for both human and livestock consumption within the land area available in all the villages, if between 30-60% of land area is cultivated with food-based crops used for village wide consumption. This would require diversion of between 50 and 90 % of current land area under oilseeds and commercial crops to cereal based crops. In villages that cultivate sufficient proportion of cereal and pulse based food crops, as little as 4 % diversion of crops towards cereals may be necessary. Results also indicate that double cropping systems can generate crop residues sufficient to provide fuel for generation of 2.6-11.3 kWh/hh/day of electricity, adequate for cooking and lighting; this could be done at the same time as providing enough primary product to satisfy food and fodder needs. / Thesis (Master, Environmental Studies) -- Queen's University, 2008-06-24 16:12:50.1

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The research objective was to calibrate a model to simulate odour dispersion downwind from natural windbreaks and then, use this model to observe the effect of windbreak characteristics and climatic conditions on the size of the odour dispersion plume. Computational fluid dynamic (CFD) models were used for the simulations because of their capability in reproducing turbulent wind conditions. The model was initially calibrated to ensure the proper velocity recovery ratio (VRR), and then to reproduce odour plumes measured in the field by three groups of four panellists. / The visual and statistical analysis of the field panellist observations indicated that a windbreak with an optical porosity of 0.35 could reduce by 21% the length of the odour dispersion plume, as compared to a site without a windbreak. Also, these analyses indicated that the site with a windbreak offering an optical porosity of 0.55 had no significant impact on the length of the odour plume, as compared to the site without a windbreak. / The models selected for the simulations were the Fluent 6.2 standard k-epsilon and SST k-o models. Their odour dispersion calibration indicated that both models can accurately reproduce the field measured odour hedonic tone and odour concentration by transforming the odour mass fraction computed by the models into the hedonic tone with a power function, and then into the odour concentration with an exponential function. The correlations between the simulated and measured absolute HT and between the simulated and measured odour concentrations were statistically significant (P < 0.01). However, the SST k-o was preferred over the standard k-epsilon because it could physically better reproduce the high turbulence conditions created by the windbreak. / The SST k-o model simulations indicated that odour plume length was mostly affected by windbreak porosity and height, as well as distance from the source. In terms of climatic conditions, odour plume size was mostly affected for atmospheric stability conditions which generally established ambient wind speed and rate of change of temperature. Wind direction has an impact on the length of the odour plume and the formation of a fin intensifying odour concentration near the windbreak, where an angle of 45º produces the shortest odour plume and the largest fin. / Key words: Simulation; odour; dispersion; natural Windbreak; CFD.

African trypanosomiasis is caused by protozoan parasites known as trypanosomes, which are transmitted by the tsetse fly, affecting both humans and animals. Trypanosoma congolense is one of the main trypanosome species affecting cattle and causes the disease known as nagana. Control of animal African trypanosomiasis currently relies on chemotherapy and vector control methods, neither of which has proven satisfactory. An effective vaccine against trypanosomiasis would be the most cost effective solution to control the disease; however, due to the phenomenon of antigenic variation, intrinsic to the parasite’s outer coat of variable surface glycoprotein, this has not yet been achieved. Recent vaccine efforts have been centred on identification of invariant parasite antigens for use as vaccine candidates. Trypanosome cytoskeleton components have in recent years been shown to be capable of providing a protective immune response against trypanosome infection. These include tubulin proteins, which form the main components of the cytoskeleton, as well as microtubule associated proteins (MAPs) and paraflagellar rod proteins. In the present study α- and β-tubulin from T. congolense were recombinantly expressed and their immuno-protective potential in mice assessed. Amplification of both α- and β-tubulin ORFs from T. congolense genomic DNA was followed by cloning of the amplicons into the T-vector pTZ57R/T, and thereafter sub-cloning into the bacterial expression vector, pET238a and the yeast expression vector pPICZαA28. Only the α-tubulin amplicon was successfully sub-cloned into pICZAαA28; however, no protein expression was achieved upon transfection of the methylotrophic yeast, Pichia pastoris, with this construct. Subcloning of both α- and β-tubulin inserts into pET28a was successful. Expression of recombinant α- and β-tubulin as fusion proteins with a histidine tag, both at a size of 55 kDa, was achieved in Escherichia coli host BL21 (DE3). Recombinant proteins were successfully purified using nickel chelate chromatography under denaturing conditions. Refolding was first attempted by dilution of purified denatured proteins in a refolding buffer followed by reconcentration, but was largely unsuccessful. A second, more successful refolding method was performed wherein denatured proteins were refolded by application of a decreasing gradient of urea, while bound to a nickel chelate column. Native tubulin from cultured T.congolense procyclics was successfully purified and renatured using a polymerisation/depolymerisation method for use as a control for immunisation. Mice were immunised separately with refolded recombinant α- and β-tubulin, native tubulin or an irrelevant protein VP4AA expressed in the same way as the tubulins. ELISA analysis confirmed the production of antibodies against each protein. Parasitaemia developed in all mice following challenge with T. congolense. Only the group immunised with β-tubulin recorded no deaths during the monitoring period despite the presence of parasitaemia, with 60% of mice immunised with α-tubulin or VP4AA and the no antigen control and no mice from the native tubulin immunised group surviving. The results showed that partial protection against trypanosomiasis caused by T. congolense infection was achieved in the group immunised with β-tubulin and suggest that β-tubulin may have vaccine potential. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

African animal trypanosomosis or nagana is a tsetse fly-transmitted disease, caused by Trypanosoma congolense, T. vivax and to a lesser extent T. brucei brucei. The disease causes major losses in revenue in many livestock-producing African countries. The available control methods, including chemotherapeutic drugs and insecticidal spraying, have become environmentally unacceptable. Antigenic variation displayed by the parasites has hindered vaccine development efforts. In this context, rather than focusing solely on the parasite itself, efforts in vaccine development have shifted towards targeting pathogenic factors released by the parasites during infection. Congopain, the major cysteine protease of T. congolense, has been shown to act as a pathogenic factor in the disease process. Analysis of the immune response of trypano-tolerant cattle revealed that these animals have the ability to control congopain activity in vivo. Therefore, congopain is an attractive vaccine candidate. To test the protective potential of congopain, immunisation studies had been conducted in cattle using the baculovirus-expressed catalytic domain of congopain (C2) in RWL, a saponin-based proprietary adjuvant from SmithKline-Beecham. Immunised animals were partially protected against a disease caused by an infection with T.congolense. Unfortunately, subsequent attempts to reproduce these results were disappointing. It was hypothesised that this failure could be due to the different expression system (P. pastoris) used to produce the antigen (C2), or the different adjuvant, ISA206 (Seppic), used, thus hinting towards an epitope presentation problem. Congopain had been shown to dimerise at physiological pH in vitro. Sera from trypano-tolerant cattle preferentially recognised the dimer conformation, advocating for protective epitopes to be dimer associated. For that reason, the present study aimed at improving the antigenicity of congopain through firstly, the elucidation of the protective epitopes associated with the dimer, secondly, the determination of the 3-D structure of the protease in order to map protective epitopes to later design mimotopes, and thirdly improve the delivery of congopain to the immune cells while maintaining the conformation of the protease by using a molecular adjuvant, BiP. A dimerisation model was proposed, identifying the amino acid residues forming the dimerisation motif of congopain. In the present study, particular amino acid residues located in the dimerisation motif were mutated by PCR-based site-directed mutagenesis to generate mutants with different dimerisation capabilities. The congopain mutants were expressed in yeast and their dimerisation capability was assessed by PhastGel® SDS-PAGE. The mutations altered both the electrophoretic mobility of the mutants and their enzymatic characteristics compared to wild-type congopain. This advocated for the involvement of these amino acid residues in the dimerisation process, although they seem not to be the only partakers. Wild-type C2 and mutant forms of C2 were heterologously expressed in P. pastoris and purified to crystallisation purity levels. Crystallisation of these proteins is currently underway, but the results are still unknown. While awaiting the crystallisation results, in silico homology modelling was employed to gain insight into the 3-D structure, using cruzipain crystal structure as a template. The modelled 3-D structure of congopain followed the common framework of cathepsin L-like cysteine proteases. Due to time constraints and awaiting the crystal-derived 3-D structure, the 3-D model of congopain was not exploited to design mimotopes with the potential to provide protection against the disease. As it was shown that protective epitopes are likely to be dimer-specific, maintaining the native conformation of congopain is essential for stimulating a protective immune response in animals. Chemically formulated adjuvants usually contain high salt concentration, at acidic or basic pH, thus might change the conformation of the protease. Adjuvants capable of efficiently delivering the antigen to immune cells while maintaining the conformation of the protease were sought. Proteins belonging to the HSP70 family are natural adjuvants in higher eukaryotes. A protein belonging to the HSP70 family was previously identified in T. congolense lysates and is homologous to mammalian BiP. Congopain was genetically fused with T. congolense BiP in order to improve antigen delivery and production of congopain activity-inhibiting antibodies. The chimeric proteins were successfully expressed in both bacteria and yeasts. The low yields of recombinantly expressed chimeras in yeast and problems associated with renaturation and purification of bacteria-expressed chimeras prevented immunisation studies in mice. However, the groundwork was laid for producing BiP-congopain chimeras for use in an anti-disease vaccine for African trypanosomosis. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.

Northern Botswana's rural agricultural settlements bordering national parks and game reserves. In two study areas (Khumaga and Gweta, bordering Makgadikgadi Pans National Park), spatial, temporal and prey-type patterns of livestock predation were assessed. Cattle, goats, horses, donkeys and sheep were the key livestock types. Lion, leopard, cheetah, wild dog, black-backed jackal, spotted hyena and the Nile crocodile (occurring only in Khumaga) were the key predators. Oral interviews with farmers in these villages provided insights into the patterns and impacts of livestock predation on rural economies. Khumaga's livestock predation scenario is dominated by lion predation on cattle, goats and donkeys, leopard predation on small stock and calves, and crocodile on goats. Wet season predation rates were higher than dry seasons', except for spotted hyena, black-backed jackal and leopard. Leopard and black-backed jackal are dominant small stock predators in Gweta. lion are the main cattle and donkey predators (though at lower frequencies). Dry season predation rates are higher. Farmers who own more livestock appear to lose more Northern Botswana's rural agricultural settlements bordering national parks and game reserves. In two study areas (Khumaga and Gweta, bordering Makgadikgadi Pans National Park), spatial, temporal and prey-type patterns of livestock predation were assessed. Cattle, goats, horses, donkeys and sheep were the key livestock types. Lion, leopard, cheetah, wild dog, black-backed jackal, spotted hyena and the Nile crocodile (occurring only in Khumaga) were the key predators. Oral interviews with farmers in these villages provided insights into the patterns and impacts of livestock predation on rural economies. Khumaga's livestock predation scenario is dominated by lion predation on cattle, goats and donkeys, leopard predation on small stock and calves, and crocodile on goats. Wet season predation rates were higher than dry seasons', except for spotted hyena, black-backed jackal and leopard. Leopard and black-backed jackal are dominant small stock predators in Gweta. lion are the main cattle and donkey predators (though at lower frequencies). Dry season predation rates are higher. Farmers who own more livestock appear to lose more cattle than those who own few. Gweta contrasts with Khumaga, having livestock predation highest during dry seasons, less reduction in livestock sales and a lower value of pending compensation claims. These predation patterns synchronise with movements of zebra and wildebeest to and from the Boteti river. Losses of livestock affect the utility derived from livestock and monetary gains from direct sales. Costs due to loss of biodiversity, though not quantified, add to those borne by the State through predator control. Both the State and the farmers loose. These losses reduce the incentives of the latter to conserve species that contribute reduction in their returns. The issue of State expenditure on predator control illustrates the possible need for re-direction of such funds into farmer-based predator control, much as an integral part of the current southern African trend of community-based natural resource management. Key words: livestock predation, predator control, economics, conservation, Botswana. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1997.

This mini-dissertation is a comparison, by repeat survey, of farmer-related threats to cheetah (Acinonyx jubatus) survival on specific commercial farms in central Namibia. The research was conducted, to investigate if there had been changes in these threats to cheetah survival over a ten-year period (June 1991 to October 2001). A sub-sample of 31 farmers who were originally interviewed by the Cheetah Conservation Fund in June 1991, were re-interviewed between July and October 2001. These farmers were exposed to the Cheetah Conservation Fund awareness-raising programme. The results of this survey were compared to the results of the original survey of these farmers. This study showed that changes in farmer-related threats to cheetah survival have taken place. These include changes in land use, the attitude and behaviour of farmers towards cheetah, and cattle management practices. The land use changes include an increase in game farming, as a major source of income, by 19% of the farmers, since 1991. This increase in game farming was associated with an increase in game proof fencing and the introduction of alien antelope species into game fenced areas. The attitude of farmers towards the presence of cheetah on their farms was found to have changed significantly (p = 0.024), with 13% more farmers than before 1991 favouring cheetah presence on their farms. The behaviour of farmers towards cheetah has also changed in favour of cheetah survival. During the ten-year period from 1991 to 2001, 23% of the farmers removed no cheetah, compared to 10% for the ten-year period before 1991. Thirteen percent of the farmers were found to remove cheetah by trophy hunting only, as opposed to none prior to 1991. During the ten-year period from 1991 to 2001, the number of cheetah removed by the same farmers had declined by 243 (55%) cheetah when compared to the previous ten-year period. Game farmers were found to remove on average 3.75 times more cheetah than livestock farmers. Five game farmers were responsible for removing 92 cheetah, representing 47% of the total number of cheetahs removed. The majority (88%) of cattle farmers experienced calf losses to cheetah predation. In contrast to this, only 44% of smallstock farmers experienced losses to cheetah predation. The mean loss of livestock to predation by cheetah was found to be low, less than one animal per year for both calves and smallstock. The majority (73%) of cattle farmers implement only one livestock management strategy to prevent predation on calves by cheetah. The majority (88%) of smallstock farmers implemented more than one strategy to prevent predation. Changes in management practices to protect calves from cheetah predation since 1991 included a 14% decline in farmers using a technique known as 'calving camps' and an increase of 42% in the number of farmers monitoring their cows during the calving season. In conclusion, during the ten-year period from 1991 to 2001, both positive and negative changes in farmer-related threats to cheetah survival were recorded amongst the farmers interviewed. The positive changes include changes in the attitude and behaviour of farmers in favour of cheetah survival. However, this progress was tempered by change in land use from livestock to game farming, since game farmers pose a greater threat to cheetah survival than livestock farmers. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2002.

Biodiversity losses are often influenced by humans due to increased demand over natural resources and retaliatory killing of wildlife as a result of human–wildlife conflicts. Large carnivores are in decline globally due to the current human–carnivore conflicts. This study was conducted in the Maasai steppe of northern Tanzania to understand the role of traditional husbandry techniques in reducing livestock predation, herding challenges that place livestock at risk for predation, willingness of pastoralists to participate in schemes for livestock security improvement, and the role of Tanzania National Parks (TANAPA) in mitigating human–carnivore conflicts. Data were collected using interviews with individuals in households and with herders in grazing fields and were reinforced with field observations. The primary husbandry strategies for livestock protection in homesteads were the bomas where livestock were enclosed at night, while in the grazing fields the strategies included: splitting livestock herds, herder among livestock, herder carrying weapons, and noise. There was no significant correlation between the wealth of an individual and the type of livestock protection strategy used at homesteads. All traditional strategies used by pastoral communities were equally ineffective in preventing livestock predation both at homesteads and in the grazing fields. However, over a four year period, there were no successful predations in any boma reinforced with chain-links, suggesting that reinforcing bomas with studier materials such as chain-link can be effective against livestock predation. Grazing in groups was found to provide more effective livestock protection in the grazing fields than any other strategy. While losing livestock by herders in the grazing fields contributed most to increased livestock predation, other herding challenges exposing livestock to predation included the seasonal nomadic lifestyle and long distances travelled by pastoral communities. The majority of respondents (91%) were willing to improve their livestock security by the use of chain-link fences at homesteads, while 87% were willing to participate in an insurance scheme for livestock security. Neither experience of livestock attack nor level of awareness of insurance scheme influenced willingness to participate in the scheme. There is growing awareness among pastoral communities of the benefits provided by carnivores and wildlife at large. Therefore, major conservation agencies such as TANAPA, Wildlife Division (WD) and other stakeholders should focus more than they have been on addressing the actual conflicts i.e. human–carnivore conflicts and helping to improve husbandry practices against predation to achieve conservation objectives by reducing retaliatory killing of carnivores.