Synergistic potententials and isolation of bioactive compounds from the extracts of two helichrysum species indigenous to the Eastern Cape province
- Authors: Aiyegoro, Olayinka Ayobami
- Date: 2010
- Subjects: Helichrysum -- South Africa -- Eastern Cape , Antibiotics , Antioxidants , Medicinal plants -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Microbiology)
- Identifier: vital:11268 , http://hdl.handle.net/10353/250 , Helichrysum -- South Africa -- Eastern Cape , Antibiotics , Antioxidants , Medicinal plants -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape
- Description: Helichrysum longifolium and H. pedunculatum belong to the Astereceae family and are used extensively in folkloric medicine in South Africa to manage stress-related ailments and as dressings for wounds normally encountered in circumcision rites, bruises, cuts and sores. The in vitro antibacterial time-kill studies, the synergistic potentials, the phytochemical screenings and antioxidant potentials as well as the isolation of the bioactive compounds from the extracts of these two plants were carried out in this study. The in vitro antibacterial activities and time kill regimes of crude extracts of H. pedunculatum was assessed. The extracts was active against both Gram positive and Gram negative bacteria tested at a concentration of 10 mg/ml. Minimum Inhibitory Concentration (MIC) values for all the susceptible bacteria ranged between 0.1 – 35 mg/ml. The average log reduction in viable cell count in time kill assay ranged between 0.17 Log10 to 6.37 Log10 cfu/ml after 6 h of interaction, and between 0.14 Log10 and 6.99 Log10 cfu/ml after 12 h interaction in 1 × MIC and 2 × MIC of the extract. The effect of the aqueous extract was only bacteriostatic on both reference and environmental strains and the clinical isolates were outrightly resistant to aqueous extract. This is worrisome and this could be one reason why, there is an incidence of high death rate resulting from circumcision wounds infection even after treating such wounds with H. pedunculatum leaf. In vitro antibacterial time kill studies of extracts of H. longifolium was assessed. All test bacteria were susceptible to the methanol extract, while none was susceptible to the aqueous extract. Two of the test bacteria were susceptible to the ethyl acetate extract, while ten and seven were susceptible to the acetone and chloroform extracts respectively at the test concentration of 5 mg/ml. The minimum inhibitory concentrations (MICs) ranged between 0.1 and 5.0 mg/ml, while minimum bactericidal concentrations (MBCs) ranged between 1.0 and >5 mg/ml for all the extracts. Average log reductions in viable cell counts for all the extracts ranged between 0.1 Log10 and 7.5 Log10 cfu/ml after 12 h interaction at 1 × MIC and 2 × MIC. Most of the extracts were rapidly bactericidal at 2 × MIC achieving a complete elimination of most of the test organisms within 12 h exposure time. The effect of combinations of the crude extracts of H. pedunculatum leaves and eight antibiotics was investigated by means of checkerboard and time-kill methods. In the checkerboard method, synergies of between 45.83-56.81 percent were observed and this is independent of Gram reaction, with combinations in the aqueous extract yielding largely antagonistic interactions (18.75 percent). The time kill assay also detected synergy that is independent of Gram reaction with a ≥ 3Log10 potentiation of the bactericidal activity of the test antibiotics. We conclude that the crude leaf extracts of H. pedunculatum could be potential source of broad spectrum antibiotics resistance modulating compounds. The interactions between crude extracts of H. longifolium in combination with six first-line antibiotics using both the time-kill and the checkerboard methods were carried out. The time-kill method revealed the highest bactericidal activity exemplified by a 6.7 Log10 reduction in cell density against Salmonella sp. when the extract and Penicillin G are combined at ½ × MIC. Synergistic response constituted about 65 percent, while indifference and antagonism constituted about 28.33 percent and 6.67 percent in the time kill assay, respectively. The checkerboard method also revealed that the extracts improved bactericidal effects of the antibiotics. About 61.67 percent of all the interactions were synergistic, while indifference interactions constituted about 26.67 percent and antagonistic interactions was observed in approximately 11.66 percent. The in vitro antioxidant property and phytochemical constituents of the aqueous crude leaf extracts of H. longifolium and H. pedunculatum was investigated. The scavenging activity on superoxide anions, DPPH, H2O2, NO and ABTS; and the reducing power were determined, as well as the flavonoid, proanthocyanidin and phenolic contents of the extracts. The extracts exhibited scavenging activity in all radicals tested due to the presence of relatively high total phenol and flavonoids contents in the extracts. Our findings suggest that H. longifolium and H. pedunculatum are endowed with antioxidant phytochemicals and could serve as a base for future drugs. Bioactivity-guided fractionation of the leaves of H. longifolium and H. pedunculatum yielded two known compounds. From the n-hexane fraction of H. longifolium a compound was isolated (Stigmasterol) and from the ethyl acetate fraction of H. pedunculatum another compound (β-sitosterol) was isolated. The compounds were isolated and identified using various techniques. The antimicrobial, anti-inflammatory, antioxidant, analgesic and anti-pyretic activities of these compounds have been reported in literatures. In general, the experiments and tests conducted in this study appear to have justified the folkloric medicinal uses of H. longifolium and H. pedunculatum for the treatment of stress related ailments and wound infections and make a substantial contribution to the knowledge base of the use of herbal medicine for the treatment of the microbial infections.
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The global financial crisis and its impact on the South African economy
- Authors: Madubeko, Vongai
- Date: 2010
- Subjects: Globalization -- Economic aspects , Global Financial Crisis, 2008-2009 , South Africa -- Economic conditions
- Language: English
- Type: Thesis , Masters , M Com
- Identifier: vital:11457 , http://hdl.handle.net/10353/363 , Globalization -- Economic aspects , Global Financial Crisis, 2008-2009 , South Africa -- Economic conditions
- Description: This dissertation investigates the effects of the financial crisis on the South African economy. In order to do this, an index which describes the financial conditions of the South African economy is constructed and computed. The index indicates that domestic South African financial conditions have deteriorated substantially during the period under study and so the study investigates how this has impacted on the country’s economic growth. A VAR model with South African variables is specified and used to assess the quantitative effects of the financial crisis on South African real GDP growth. Results suggest that the South African economy was not significantly affected by the crisis, but economic growth was slowed down and may still grow substantially slower in the next few years due to the financial crisis. These results corroborate the theoretical predictions and are also supported by previous studies.
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The impact of ICTs for agricultural development in the rural community: a case study of Alice, Eastern Cape, South Africa
- Authors: Alao, Abiodun Oyebimpe
- Date: 2010
- Subjects: Community information services -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa -- Eastern Cape , Agricultural productivity -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc (Com)
- Identifier: vital:11363 , http://hdl.handle.net/10353/236 , Community information services -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa -- Eastern Cape , Agricultural productivity -- South Africa -- Eastern Cape
- Description: This study investigates the impact of ICTs for agricultural development in the Alice rural community. The rationale for carrying out the study has to do with the limited access to ICTs by farmers residing in this rural community which in turn affects their productivity and increase in the volume of agricultural production. The core argument of the study is that the use of ICTs has positive spinoffs on agricultural development which leads to improvement in the quality and quantity of agricultural production. Conversely lack of access to ICTs can result in inability to enhance agricultural productivity in rural areas such as Alice. Furthermore, it is argued herein that technological information devices such as ICTs are essential communication and information tools; and as such, should be regarded as useful communication media for disseminating relevant agricultural information to farmers residing in rural communities. In conducting this study theoretical frameworks such as Rogers’ diffusion of innovation and development theories encompassing both the participatory approach and development support communication were presented and argued for as approaches suitable for the study. Triangulations of research methods, such as, qualitative and quantitative methods, were utilized for the collection of data for this study. As is common practice, the triangulation method was used in cross checking and supplementing data/information collected through the utilization of each of the methods. Interviews and questionnaires were used as data collection tools for this study owing to their ability to generate clear and precise responses or answers to the questions posed. The key findings of the study show that the limited access to ICTs in the Alice rural community was caused by factors such as low level of literacy, age and language barriers which in turn affected the adoption of ICTs amongst the Alice farmers. Amongst the recommendations emanating from this study is the idea that the adoption of ICTs for agricultural information can be fast-tracked through the implementation of telecentres/kiosk and information centers for easy access to information and communication services in the rural community.
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The impact of rural ICT projects in South Africa: a case study of Dwesa, Transkei, Eastern Cape, South Africa
- Authors: Shingai, Kavhai Mitchell
- Date: 2010
- Subjects: Information technology -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Internet--South Africa -- Eastern Cape , Project management -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Soc Sc (Com)
- Identifier: vital:11362 , http://hdl.handle.net/10353/317 , Information technology -- South Africa -- Eastern Cape , Rural development projects -- South Africa -- Eastern Cape , Internet--South Africa -- Eastern Cape , Project management -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
- Description: This project aimed at assessing and evaluating the extent to which deployed ICTs in the rural area of Dwesa have impacted on the lives of the residents there. This occurred between February 2008 and December 2009. The ICTs are an initiative collaboration of University of Fort Hare and Rhodes University, sponsored by Telkom SA, the Government of Finland and other market players. This research started by reviewing the extent to which rural areas in general have lagged behind in terms of accessing ICTs, paying closer attention to governmental policies and initiatives towards rural development. The project then looked at the currently available ICTs in Dwesa and trying to measure the extent to which they have been useful or rather complicated the lives of the people there. Also important was a review of the efforts made by the technology innovators towards ensuring that relevant and appropriate technologies were made available to the rural people. The project also looked into issues of sustainability, maintenance and general running of the project to ensure its success. Important key findings on access, appropriateness of ICTs, use and knowledge about the ICTs, literacy levels, education standards and readiness of community to use ICTs were made during this research. Also included in the findings are issues on state of infrastructure, already present services, and current uses of ICTs as well as notable positive ICT impact in Dwesa. The most important findings of this research were to assist in providing a detailed prediction of future impact of various possible new technologies that can be introduced to Dwesa. This research also had to be able to bring out a monitoring and evaluation system that should measure the impact of the ICT interventions over the past 5 years. This project was initiated in 2005 and is identified by the name Siyakhula Living Lab. The concept of a living lab is a new term for providing ICTs in an area where their usefulness can be tested based on the natural environment in which they are being used.
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The impact of the Western conceptualization of the Christian gospel on its communication in a non-Western environment, with particular reference to the AmaXhosa
- Authors: Higgs, Michael John
- Date: 2010
- Subjects: Christianity and culture -- South Africa , Church history , Missions -- South Africa -- Eastern Cape , Xhosa (African people) -- Religion , Communication -- Religious aspects -- Christianity
- Language: English
- Type: Thesis , Doctoral , D Th
- Identifier: vital:11800 , http://hdl.handle.net/10353/356 , Christianity and culture -- South Africa , Church history , Missions -- South Africa -- Eastern Cape , Xhosa (African people) -- Religion , Communication -- Religious aspects -- Christianity
- Description: This thesis examines the extent and nature of the impact of the contextualization of Christianity upon the amaXhosa from the missionary irruption in the nineteenth century to the present day, and proceeds to examine the implications of this impact for the presentation of the Christian gospel in the contemporary Eastern Cape. Chapter One describes the problem, offers definitions of key concepts and outlines the procedural method for the rest of the thesis. Chapter Two deals with the question of the cross-cultural communication of the Christian gospel in theory. Doctrinal questions such as the nature of the gospel are examined. The basic hermeneutical issue of the categorization of doctrinal tenets according to whether they are required or simply permitted is discussed in terms of Osborne's categories: 'cardinal', 'non-cardinal'. Tenets which are found to be 'anti-scriptural' would be rejected. Specific hermeneutical topics such as language and meaning, symbolics, textuality and orality are then discussed. This is followed by a survey of secular influences which affect a conceptualization. This chapter is preparatory to, and definitive for, the discourse which follows. Chapter Three outlines the cultural heritage from which the Western missionary contextualization of Christianity developed. It shows the extent to which this presentation of the gospel was dependent upon the philosophy which Britain and Europe inherited from the classical Greek culture. More modern developments such as the Enlightenment, Empiricism and Historicism bring the discourse up to the point at which the missionaries arrived. Chapter Four deals with the initial encounter between the missionaries and the amaXhosa. A brief account is given of the nature of the religious and spiritual aspects of the Xhosa culture which first encountered Christianity. The doctrinal section of this chapter deals with those doctrines in the missionary message which became issues for the amaXhosa. The hermeneutical section shows how the cultural setting of the West (vii) affected both the contextualization by the missionaries and the conceptualization by the amaXhosa. To a large extent, the missionaries made the double mistake of imposing their culture on the amaXhosa and failing to accord respect, even recognition, to the Xhosa culture. This amounted to imperialism, which, together with the political imperialism of Britain as the colonizing power, evoked responses from the Xhosa community which are outlined in section 4.4, including those of Nxele and Ntsikana. Because the impact of the Western contextualization is an on-going phenomenon, the thesis continues to trace its development up to the present time. Apartheid is briefly mentioned in Chapter Five. The point is made that all white people were perceived by the amaXhosa to be Christians, and the architects and practitioners of apartheid claimed to be Christians. This ideology therefore had a direct effect on the Xhosa conceptualization of the gospel. The architects of apartheid actually believed that they were accepting God's gift and mandate. This chapter includes Black theological reaction to apartheid in terms of the South African version of Liberation theology. Chapter Six returns to Western Theology in order to bring the sphere of discourse from the point at which it left off at the end of Chapter Three up to the present time. The schools of thought in this period are: Secularism and Existentialism, together with their theological extension, Demythologization. The main religious movements are the Charismatic Movement and Neo-Pentecostalism. Postmodernism came as a later philosophical school, to be followed by Globality. Chapter Seven deals with black South African reactive and proactive responses. The predominant theologies are those of Dwane, Buthelezi, Boesak and Mtuze. Although Dwane, Buthelezi and Boesak came on the scene at the same time as the black theologians reviewed in Chapter Five, their work is placed here because it differs significantly from the more radical responses of the latter. Mtuze is post-apartheid, and responds to the developments outlined in Chapter Six. Chapter Eight draws the findings of the thesis together, by considering how the Christian Gospel ought to be presented to the various contemporary sub-cultures of the amaXhosa. (viii) The last Chapter applies the findings of the thesis to the task in hand. The desired outcomes are listed and briefly discussed. The task ahead is enunciated in terms of manpower and other resources for the effective communication of the Christian gospel in the twenty-first century. The past, present and projected programmes of the Bible Institute Eastern Cape [the target institution] are described and assessed. Finally, topics which presented themselves in the course of the preparation of this thesis are suggested for future research.
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The implementation of an integrated quality management system in Queenstown District schools: experiences from the Isibane Circuit
- Authors: Sambumbu, Antony Matemba
- Date: 2010
- Subjects: School management and organization -- South Africa -- Eastern Cape , Education and state -- South Africa -- Eastern Cape , Education -- South Africa -- Eastern Cape , High schools -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: vital:11643 , http://hdl.handle.net/10353/355 , School management and organization -- South Africa -- Eastern Cape , Education and state -- South Africa -- Eastern Cape , Education -- South Africa -- Eastern Cape , High schools -- South Africa -- Eastern Cape
- Description: This study examines the experiences of the school management teams and educators of the Isibane Circuit in the Queenstown District, regarding the implementation of an Integrated Quality Management System (IQMS) policy at school level. Following an agreement reached in 2003 between the South African Education Department and the major teacher organisations in this country, the IQMS was scheduled to be implemented in public schools from 2004. Two major challenges are identified and explained: accountability and development of human resources, as well as contradictions between internal and external evaluations. The study also elaborates on the changes in the educational history from the apartheid system to the democratic system of education. Nine schools participated in the study (two secondary schools and seven primary schools). These schools were purposely selected due to the fact that they had started implementing the IQMS policy, which was the main criterion for selection. Semi-structured interviews were used to gather data from principals, Heads of Departments as well as post-level one educators concerning their experiences of the IQMS implementation. The findings indicated that while the IQMS policy was good on paper, it was extremely difficult to implement. Issues of honesty and trust were at the root of difficulties that made the IQMS implementation challenging. The participants‟ understanding of IQMS was that it was intended for the provision of quality education and development.
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The nature and extent of child labour in Zimbabwe: a case study of Goromonzi District farms in Zimbabwe
- Authors: Musandirire, Sally
- Date: 2010
- Subjects: Child labour -- Zimbabwe , Child abuse -- Zimbabwe , Child welfare -- Zimbabwe , Child prostitution -- Zimbabwe , Children's rights -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MA (Human Rights)
- Identifier: vital:11097 , http://hdl.handle.net/10353/266 , Child labour -- Zimbabwe , Child abuse -- Zimbabwe , Child welfare -- Zimbabwe , Child prostitution -- Zimbabwe , Children's rights -- Zimbabwe
- Description: The study examines the nature and extent of child labour in Goromonzi District farms in Zimbabwe. The main objective of the study was to investigate the nature and extent of child labour in Goromonzi District farms. The study reveals high levels of child exploitation and abuse. A qualitative design was chosen and purposive sampling was used. Interviews were used to collect data. The sample consisted of 40 children between 7 and 16 years. Interviews were also conducted with the Coalition Against Child Labour in Zimbabwe (CACLAZ). CACLAZ is an NGO that specializes in the elimination of child labour in Zimbabwe through the provision of education. The study reveals different forms of child labour. These include children working in communal and commercial farms, children working in domestic set up and child prostitution. The study exposes some of the causes and effects of child labour. Poverty, increased cost of education, and cultural practices were some of the causes of child labour. The study also reveals gaps that exist in the LRA. In view of the findings, the study makes recommendation on how to curb child labour and protect the rights of children as enshrined in various international instruments such as the CRC and ILO Conventions.
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The role of school discipline in combating violence in schools in the East London region
- Authors: Smit, Marie Elizabeth
- Date: 2010
- Subjects: School violence -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , M Ed
- Identifier: vital:16164 , http://hdl.handle.net/10353/224 , School violence -- South Africa -- Eastern Cape
- Description: This study focuses on the role of discipline in the establishment and maintenance of a safe school environment for learners and educators. In a mainly qualitative investigation, empirical data from four primary schools and five high schools in the East London Region of the Eastern Cape Province were collected by means of individual interviews and questionnaires. Historico-legal research also formed part of the literature review, thus law reports and articles from South Africa and other countries were included as part of the research process. This was done to shed light on the legal consequences of school violence and discipline, affecting the safe learning environment of learners. Perceptions of educators and learners in the selected schools regarding discipline and violence at their schools were collected by means of a survey. Three hundred and thirty questionnaires were completed by learners from the selected schools, and nine interviews were conducted with either the principal or a member of the senior management team of each school. The researcher also conducted further in-depth interviews with twenty learners from four schools (two primary and two high schools). These data were analysed in accordance with accepted procedures for qualitative data processing. The data revealed that a culture of violence exists in these schools, and that corporal punishment is still practised. Learners’ perceptions on safety and discipline at their schools revealed that bullying persists, especially when there is no teacher supervision. Participating educators’ experiences suggested the need for promoting positive discipline, and creating a safe learning environment for all, by involving parents in the education process and involving them in drawing up a code of conduct for the school.
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The role played by business development services providers (BDSs) in improving access to finance by start-up SMEs in the Buffalo City Municipality
- Authors: Musara, Mazanai
- Date: 2010
- Subjects: Small business -- Finance , New business enterprises , Business enterprises -- Finance , Corporations -- Finance , Small business marketing
- Language: English
- Type: Thesis , Masters , M Com (Business Management)
- Identifier: vital:11315 , http://hdl.handle.net/10353/359 , Small business -- Finance , New business enterprises , Business enterprises -- Finance , Corporations -- Finance , Small business marketing
- Description: Small and medium enterprises (SMEs) are very important to employment creation, poverty alleviation and the sustainable economic development of a nation. Encouraging SMEs, especially start-ups is crucial for sustainable economic growth. However, the failure rate of start-up SMEs in South Africa is one of the highest in the world. In reviewing the literature of the causes of the failure of start-up SMEs, access to finance emerged as a prime challenge. Start-up SMEs find it very difficult to obtain external finance from commercial banks and venture capitalists. The national and provincial governments in South Africa have realised that access to finance is a major constraint to the growth and survival of start-up SMEs and have put in place certain measures to improve access to finance by start-up SMEs. One of the primary measures put in place by government to improve access to finance by start-up SMEs is the provision of Business Development Service by some government agencies. This research investigates the role of Business Development Services Providers (BDSs) in improving access to finance for start-up SMEs. Questions arise as to why the failure rate of start-up SMEs is high in South Africa despite all these government measures aimed at assisting start-ups to access finance. Empirical research was conducted to investigate the role of BDS in improving access to finance by start-up SMEs. The instrument used for data collection was the self-administered questionnaire. The statistical analyses included descriptive statistics, T-test, ANOVA, correlation and regression analysis. The Cronbach‟s alpha was used as a measure of reliability. The results of the study revealed that: Access to finance is still a major problem hindering the survival of start-up SMEs. There is a lack of awareness of BDS providers and their services by the majority of start-up SMEs. There is a significant positive relationship between the use of BDS by start-up SMEs and success in accessing finance. Start-up SMEs that are aware of BDS do make use of the services. The results suggest that BDS are important to improving access to finance by start-up SMEs. However, there is a need to build awareness and encourage the use of BDS by start-up SMEs to improve their access to finance and ultimately increase their chances of survival.
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Tillage and crop rotation impacts on soil, quality parameters and maize yield in Zanyokwe Irrigation Scheme, South Africa
- Authors: Njaimwe, Arnold Ngare
- Date: 2010
- Subjects: No-tillage , Soil mechanics , Soils -- Quality , Cover crops , Corn -- Irrigation
- Language: English
- Type: Thesis , Doctoral , PhD (Soil Science)
- Identifier: vital:11962 , http://hdl.handle.net/10353/460 , No-tillage , Soil mechanics , Soils -- Quality , Cover crops , Corn -- Irrigation
- Description: Intensive tillage and monoculture cropping practices reduce soil C accumulation hence increasing soil vulnerability to chemical, physical and biological degradation. This study focussed on enhancing biomass production of wheat and oat winter cover crops as a means of increasing C sequestration in the low organic C soils of the central part of Eastern Cape Province. The specific objectives were (i) to evaluate the short-term effects of no till and cereal-fallow based crop rotations on; soil organic matter related parameters, pH and electrical conductivity, (ii) soil bulk density, water retention and aggregate stability, (iii) soil microbial biomass C and N, mineralizable N, soil respiration, and dehydrogenase enzyme activity, (iv) grain yield, soil nutrient concentration (N, P and K) and their uptake by maize, and (v) to identify soil parameters with high sensitivity to tillage under maize-fallow-maize, maize-wheat-maize and maize-oat-maize rotational cover cropping practices. The experiment was laid out as a split-plot arrangement in a randomized complete block design with 4 replicates. Tillage treatments (CT and NT) were applied on the main plots which measured 8 × 18 m while crop rotation treatments were applied in the subplots which measured 8 × 6 m. The rotation treatments were maize-fallow-maize (MFM), maize-wheat-maize (MWM) and maize-oat-maize (MOM). Weed control in NT plots involved preplant application of glyphosate to control mainly the grass weeds while post emergence weed management was done using Atrazine (485 atrazine and 15 g l-1 triazines). Initial weed control in CT plots was achieved through ploughing to a depth of 20 cm followed by disking while post emergence weed iii management was done by hand hoeing. Soil parameters measured were; (i) particulate organic matter (POM), soil organic carbon (SOC), total nitrogen (TN), pH and electrical conductivity (EC), (ii) soil bulk density (b), moisture at field capacity (FC), aggregate mean weight diameter (MWD) determined by fast wetting (FW), slow wetting (SW), mechanical breakdown by shaking (MB) and the stability index (SI), (iii) soil microbial biomass C (MBC) and N (MBN), mineralizable N (MN), soil respiration (SR), and dehydrogenase enzyme activity (DHEA). No-till increased POM and TN compared to CT in Lenye and Burnshill, respectively. The MWM and the MOM rotations increased TN relative to the MFM rotation in Lenye. The MWM and MOM rotations enhanced SOC relative to MFM in all sampled soil depths at Burnshill and similar observations were made under MOM rotation in the 5-20 cm depth in Lenye. The MWM and MOM rotations tended to depress soil pH relative to the MFM rotation in both sampled soil depths in Lenye while NT reduced soil pH relative to CT on the surface soil layer in Burnshill. Soil EC and pH varied with depth across tillage practices but both parameters remained within the ideal range for successful crop production over the study period. Soil stability index (SI) and aggregate MWD determined by FW, SW and MB were higher in Lenye compared to Burnshill. The MOM rotation enhanced the SI relative to MFM and MWM rotations at both sites. Scanning electron microscope (SEM) showed that more organic C was incorporated into the soil under NT and MOM rotation compared to CT and MFM rotation which had few organic coatings on the soil particles. Microbial properties varied with plant biomass input as influenced by tillage and type of rotational cover crop at both sites. Like in other past studies, NT showed higher levels of MBC, MBN, NM and SR at the soil surface layer compared to CT in Burnshill. No till increased MN iv relative to CT in both sampled soil depths in Lenye and resulted in higher DHEA compared to CT in Burnshill. The MOM rotation increased MBC, MBN, MN relative to MFM rotation especially within surface soil layer. Similar observations were made with respect to MN and SR in both sampled soil layers at Lenye. By contrast, the DHEA was higher under the MFM relative to the MWM and MOM rotations in Lenye but similar under the MFM and MOM rotations in Burnshill. Maize grain yield was not affected by both tillage and crop rotations but varied with cropping season. Comparable grain yields observed under the two tillage practices with similar fertilizer application rates indicated the advantage of NT over CT in saving on labour costs in maize production without compromising yields. High plant biomass retention under NT relative to CT contributed to high soil N and P levels under the former compared to the latter tillage practice especially on soil surface layer at both study sites. Principal component analysis (PCA) revealed that soil chemical and biological parameters closely linked to organic matter, namely SOC, MN, MBC and MBN showed the highest sensitivity to tillage and crop rotation treatments. Soil aggregate MWD determined by SW and b were the physical parameters which were highly altered by agronomic management practice. The MWM and MOM rotations were clustered together and clearly separated from the MFM rotation and this observed trend only applied to the 0-5 and 5-20 cm depths in Lenye site only. No till, MWM and MOM rotations enhanced POM, SOC and TN relative to CT and MFM rotation suggesting these practices have greater potential to improve soil chemical properties compared to intensive tillage and maize monoculture based production practices. Reduced soil b under MOM rotation and improved SI under NT compared to MFM and CT, respectively v indicate that these practices have the potential to improve degraded soils. Although not significantly different, NT values for MBC, MBN, MN, SR and DHEA were higher compared to CT indicating the potential of the practice to improve soil biotic activity relative to conventional tillage practices. No till enhanced surface soil nitrate N and extractable P compared to CT at both sites revealing the long-term potential of NT in improving the supply of these essential plant nutrients compared to CT. Principal component analysis showed that SOC, MN, K, P, MBC, MBN, soil aggregate MWD determined by SW and b were the most sensitive parameters to tillage and crop rotations. Therefore, these parameters could constitute the minimum data set for assessments of the impact of selected CA practices on soil quality attributes.
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Time budgets, avoidance distance scores-related behaviour and milk yield of pasture-based Jersey, Friesland and cross bred cows
- Authors: Dodzi, Madodana Sunson
- Date: 2010
- Subjects: Dairy products -- Analysis , Jersey cattle , Milk yield , Dairy cattle -- Feed utilization efficiency , Dairy farming
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11817 , http://hdl.handle.net/10353/474 , Dairy products -- Analysis , Jersey cattle , Milk yield , Dairy cattle -- Feed utilization efficiency , Dairy farming
- Description: Time budgets, avoidance distance scores-related behaviour and milk yield of pasture-based Jersey, Friesland and crossbred cows. by Madodana Sunson Dodzi The study was conducted at the University of Fort Hare farm to determine the time budgets, the avoidance-related behaviour variables and their relationship with milk yield in three pasturebased dairy genotypes: Jersey, Friesland and crossbreed. Twenty one clinically health dairy cows aged between 52 and 55 months, in mid lactation and comprising of seven cows from each genotype were used in the study. The time spent on different activities (grazing, lying down, standing and others) at pasture was recorded using stop watches across four seasons. The behavioural responses of the three genotypes to humans were determined by recording their avoidance distance scores (AD), exit speed (ES), pen scores (PS), pen behaviour scores (PBS), plat form scores (PLS) and the occurrence of kicking (KCK) and stepping (SPG) during milking on four consecutive days in four seasons. Time spent standing was higher (P < 0.05) for Friesland compared to Jersey and crossbred during the hot-wet season. In the cool-dry season the Jersey spent more time (P < 0.05) grazing than the other breeds. The Friesland and crossbred on the other hand devoted most of their time lying down compared to Jersey in the cool- dry season (P < 0.05). There were season differences in time spent on all activities (P < 0.05). Time spent on grazing was longest in post-rainy seasonal and lowest in hot- wet season (P < 0.05). The longest lying down period was observed in the hot-dry season and lowest in hot-wet season (P < 0.05). iii Daily milk yield Varied (P < 0.05) with genotype with the Friesland and Jersey producing higher yield than the crossbred. The highest amount was produced in hot-dry and the least in hot-wet season. Milk yield was positively correlated (P < 0.05) with lying down. Standing was negatively correlated with milk yield (P < 0.05). The Friesland had the highest avoidance distance scores (P < 0.05) and the Jersey had the lowest avoidance distance scores in all seasons. There was an association (P < 0.05) between genotype and exit speed scores, pen scores and stepping behaviour scores. The Friesland exhibited the highest exit speed scores than the other breeds. The Jersey had the lowest (P < 0.05) kicking behaviour scores. There was a relationship (r = 0.64) between avoidance distance scores and exit speed. Exit speed scores were correlated with pen score(r= 0.23). Milk yield was significant related (r= 0.17) to the occurrence of kicking behaviour. The genotypes showed different levels of sensitivity to season and milk yield was influenced by breed and season. It can be concluded that time budgets vary with season and farmers need to adopt measures that buffer the effect of season on welfare of dairy cows. It can also be concluded that avoidance distance scores differs according to genotype with Jersey being more confident to humans than other two breeds. It is therefore recommended that provision of shades or cooling mechanism should be adopted to buffer the effects of hot-wet season. Improving quality of feed during the cool-dry season may be critical for Jersey cows. Finally positive handling of the dairy cows is recommended in order to improve the welfare and milk yield of pasture based dairy cows.
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Validating the use of Hippobromus pauciflorus (L.f) Radlk for the treatment of eye infections in the Eastern Cape South Africa
- Authors: Pendota, Srinivasa Chary
- Date: 2010
- Subjects: Medicinal plants -- South Africa -- Eastern Cape , Herbs -- Therapeutic use , Eye -- Infections -- South Africa -- Eastern Cape , Sapindaceae
- Language: English
- Type: Thesis , Doctoral , PhD (Botany)
- Identifier: vital:11303 , http://hdl.handle.net/10353/d1001052 , Medicinal plants -- South Africa -- Eastern Cape , Herbs -- Therapeutic use , Eye -- Infections -- South Africa -- Eastern Cape , Sapindaceae
- Description: An ethnobotanical survey of plants used for the treatment of eye infections was carried out in the Eastern Cape Province of South Africa. The study revealed that 12 plant species are commonly used with Hippobromus pauciflorus (L.f) Radlk being the most frequent. The crude extracts of the leaves, stem bark and roots of the plant were investigated for antimicrobial activity against 10 bacterial and four fungal strains. The methanol extracts of the plant parts were the most active and showed appreciable activity against Gram-positive and Gram-negative bacteria. The methanol extracts of the leaves and stem bark inhibited the growth of fungi with activities ranging from 78.70 percent to 100 percent on Aspergillus niger and Penicillium notatum. The acetone extracts of the leaves and stem bark were active against A. niger (51.76 percent) and P. notatum (77.22 percent). The aqueous extract of Hippobromus pauciflorus leaves at 50, 100 and 200 mg/kg body weight doses were evaluated for anti-inflammatory, analgesic and antipyretic activities in male Wistar rats. Anti-inflammatory activity was studied by using carrageenan-and histamine induced oedema right hind paw volume while the analgesic effect was evaluated using formalin-induced pain and tail flick nociception response. The brewer’s yeast-induced pyrexia model was used for the antipyretic investigation. The extract at all the doses used significantly inhibited both the carrageenan- and histamine-induced inflammation in a manner that was not dose dependent. The extract reduced the formalin-induced pain licking as well as prolonged the reaction time in the tail flick-induced pain. The effects of the aqueous extract of the plant leaves at 50, 100 and 200 mg/kg body weight doses were investigated for 14 days on some biochemical parameters of male Wistar rats. The extract at all the doses tested did not significantly alter the levels of white blood cells, red blood cells, mean corpuscular volume, platelets, neutrophils, monocytes, lymphocytes and large unstained cells. While the levels of haemoglobin, packed cell volume and basophils increased at specific doses, those of mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and eosinophils decreased. In vitro antiviral activities of the plant against herpes simplex virus type 1(HSV-1) and coxsakie virus B6 were investigated. Cytotoxicity was evaluated by MTT assay in Vero cells. At concentrations ranging from 165-270/μg/ml there was significant antiviral activity against HSV-1, but toxicity was also noted. There was no antiviral activity against coxsakie virus B6. Bioactivity-guided fractionation of the leaves of H. pauciflorus yielded three known compounds. From the ethyl acetate fraction, two compounds were isolated (epicatechin and -sitosterol ) and from the n- hexane fractions, one compound (lupeol) was isolated. They were isolated and identified using various techniques. The antimicrobial, anti-inflammatory, analgesic and anti-pyretic activity of these compounds have been reported in literature. The structure and distribution of foliar appendages on the leaves of H. pauciflorus were examined by scanning electron microscope. The leaves have long unicellular nonglandular trichomes which were distributed over the mid rib and densely populated at the edges of the adaxial and abaxial surfaces. In general, the experiments and tests conducted in this study appear to have justified the use of Hippobromus pauciflorus for the treatment of eye infections and make a substantial contribution to the knowledge base of the use of herbal medicine for the treatment of the eye infections.
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Women, land rights and HIV/AIDS in Zimbabwe: the case of Zvimba communal area in Mashonaland West Province
- Authors: Arisunta, Caroline
- Date: 2010
- Subjects: Land tenure -- Zimbabwe , AIDS (Disease) in women -- Zimbabwe , Agricultural productivity -- Zimbabwe , Women farmers -- Zimbabwe , Women in agriculture -- Zimbabwe , Widowhood -- Zimbabwe , Inheritance and succession -- Zimbabwe , HIV-positive persons -- Zimbabwe
- Language: English
- Type: Thesis , Masters , M Soc Sc (Rural Development)
- Identifier: vital:11939 , http://hdl.handle.net/10353/233 , Land tenure -- Zimbabwe , AIDS (Disease) in women -- Zimbabwe , Agricultural productivity -- Zimbabwe , Women farmers -- Zimbabwe , Women in agriculture -- Zimbabwe , Widowhood -- Zimbabwe , Inheritance and succession -- Zimbabwe , HIV-positive persons -- Zimbabwe
- Description: This study explores women’s access to land under the customary tenure system. It examines how the changes in land tenure, access and rights to land as a consequence of HIV/AIDS are affecting agricultural productivity, food security and poverty, with a specific focus on women who have lost their husbands to HIV/AIDS in Zvimba. Zvimba is a village community located in Zvimba District in the Mashonaland West Province of Zimbabwe. The study also discusses policy responses designed to cushion the impact of HIV/AIDS on local communities especially women living with HIV/AIDS. The study highlights the vulnerability of widows to land rights violations, mainly inflicted by relatives but sometimes by the wider community. The main form of abuse encountered included the use of abusive language, threats of evictions and at times, beatings. The legal route for seeking redress was rarely used. Fear of witchcraft, low educational levels and fear of causing conflict between children and their paternal relatives also led widows to abandon the fight for their rights. The study further reveals that widows are heavily exposed to dispossession of their land rights. HIV/AIDS has increased the vulnerability of widows and other women to threats and dispossession of their land and other property rights. Dispossession of arable fields was observed in the four wards. The dispossessions and threats to livelihoods were directly related to the HIV positive status of the widows. The findings from this study illustrate the predominant role that male members of the household or family have over land. Thus, culture and traditional practices still affect women in other cases, disadvantaging them in favour of men, as in inheritance of land and property in the household.
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