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    Selection of DNA aptamers against Cancer-Targeting Murine Antibodies

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    Access restricted. Access embargoed until 2025.Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 202

    Status and potential of green infrastructure to support urban resilience in Zomba City, Malawi

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    Small and medium towns with less than one million inhabitants are regarded to be the fastest growing urban centres globally, absorbing the bulk of the urban population growth. This urban growth drives the diminishing natural capital within the urban settings, resulting in compromised ecosystem services delivery, thereby rendering urban dwellers and systems less resilient to hazards and shocks. It is known that urban resilience discourse is rooted in robust, empirical assessments of the nature, composition and distribution of urban green infrastructure. Using the concept of green infrastructure, a mechanism for the delivery of ecosystem services that are multi-functional, well connected, and that integrate the grey-green infrastructure while providing room for social inclusion, anchored the research in a small city of Zomba, Malawi, which is a fast-growing city facing natural resource and ecosystem service degradation. The research therefore was set to understand the status of urban green infrastructure in Zomba over space and time as the basis for enhancing urban resilience. This was facilitated by an understanding of the spatial and temporal quantity, quality, diversity and distribution of urban greenspaces and the composition, structure, diversity and distributional differences of urban trees within different urban greenspace classes. Further to this was an investigation on the perceptions of and preferences for urban greenspaces among the different socio-demographic groups and finally the role of residents, institutions and institutional frameworks in building urban resilience through the delivery of ecosystem services. To achieve these objectives, the study used a suite of methods. First was geographical information system and remote sensing to understand the spatial and temporal changes in greenspaces within the city in terms of quantity and distribution. Ecological methods of assessing the tree species composition, diversity, population structure and distribution were also employed. To gauge the perceptions of and preferences for urban greenspaces, a survey was done, targeting users found within the urban greenspaces plus residents that claimed to have patronised the urban greenspaces. Finally, to understand the role of nature and the relevant urban ecosystem services provided towards building urban resilience, remote sensing and key informant interviews were done to enrich the literature searches on a case study of urban community efforts involved in managing Sadzi hill to reverse ecosystem disservices versus Chiperoni hill that was not managed. A general impression of declining urban green infrastructure was verified through the study. The city has indeed lost 14 % tree cover between 1998 and 2018 due to increased housing and creation of agricultural land to support the growing urban population. The city has 168 tree species with 65 % of them being indigenous. Residential areas were dominated by exotic trees, mainly due to the abundance of exotic fruit trees like Mangifera indica. Generally, the city has a good tree diversity score but unequally distributed, with the formal residential areas, where the colonial masters settled, having more trees than the mixed and informal residential areas. Nine urban greenspace types were identified, but there was a low per capita urban greenspace area of 11.6 m2 per person, slightly above the minimum standard set by World Health Organisation. From the preferences for and perceptions of urban greenspaces, patronage to these greenspaces (treated as parks) was highest among the educated youth, a majority being from the high housing density areas where there are no urban parks. Walking to the nearest urban greenspace took more than 10 minutes for 85 % of the respondents. With the available by-laws in support for the governance of greenspaces within the city and the role of residents towards the same, restoration efforts that targeted Sadzi hill yielded positive results through reversing ecosystem disservices that were being experienced by the community members around the hill. The community enjoys several ecosystem services that have also contributed towards building their resilience to climatic and environmental hazards. The results of this study have unveiled several green infrastructure attributes that can contribute towards building urban social ecological resilience like the presence of high proportion of indigenous tree species, healthy urban forest, high proportion of fruit trees, high diversity scores, unparalleled demand for urban greenspaces for cultural and regulatory ecosystem services, the willingness to pay and work towards managing and conserving greenspaces and the social capital available from the urban communities. However, the study also unveiled several green infrastructure related attributes that if not checked will continue to undermine efforts towards building urban resilience. These included the continued drop in tree and greenspace cover, poor governance of the available public greenspaces, unequal distribution of trees and urban greenspaces, poor management of greenspaces, bare river banks, lack of park amenities and a lack of a clear strategy, policy or an urban plan that clearly outlines green infrastructure. Efforts towards addressing these will mean acknowledging the role of green infrastructure in supporting urban social ecological resilience.Thesis (PhD) -- Faculty of Science, Environmental Science, 202

    Chemical analysis and biological activities of crude extracts and essential oil of selected medicinal plants from the Eastern Cape, South Africa, and Volta Region of Ghana

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    Lantana camara and Khaya grandifoliola extracts are among many plants found traditionally effective for the treatment of wounds and ulcers. This study assessed the phytochemical content, isolation and identification of single compounds from methanol and ethyl acetate extracts of Lantana camara and Khaya grandifoliola. Further, the bioactivity testing including antioxidant, antimicrobial and cytoxicity of the extracts was done to confirm the wound healing potential discovered by the traditional healers. Materials and methods: Extraction was done successively using maceration method with 100 % ethyl acetate and 100 % methanol with a biomass-to-solvent ratio of 1:3 (w/v) to obtain L. camara ethyl acetate extracts of berry (ELB), flower (ELF) and leaf (ELL) and methanol extracts of MLB, MLF, MLL and K. grandifoliola ethyl acetate extracts of leaf (EKL), root (EKR) and stem bark (EKSB) and methanol extracts of MKL, MKR, MKSB respectively. L. camara leaf essential oil (EO) was extracted using the hydro-distillation method with a Clevenger apparatus. Total phytochemical content was assessed for each extract using spectrophotometric methods and a calibration curve of standards: bromocresol green method with atropine; Folin–Ciocalteu colorimetric method with gallic acid, aluminium chloride colorimetric method with quercetin and concentrated sulphuric acid chloroform with linalool for total alkaloid, phenolic, flavonoid and terpenoid contents respectively. Single compound isolation and purification was conducted using chromatographic techniques. Elucidation of single compounds was done using spectrometric method, high resolution- mass spectrometry, and one and two-dimensional (1D and 2D)-NMR. Stereochemistry of each compound was confirmed using electronic circular dichroism spectra. A Crystalline compound was identified by single crystal X-ray diffraction using CuKα-radiation. In vitro bioactivities were assessed with methods such as 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide, free radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl, inhibitory effect on nitric oxide production in lipopolysaccharide-activated RAW 264.7 macrophages, and 96-well plate micro dilution for cytotoxicity, ant-inflammatory and antimicrobial activity testing. Results: Methanol extracts of both plants retained high phytochemical concentrations of all the phytoconstituents investigated compared with the ethyl acetate extracts which retained lower concentrations. The results of the L. camara methanol extracts include; total alkaloid content (TAC) (2.05±0.18, 1.87±1.54 and 2.60±1.10 mg AEQ/100 mg); total phenolic content (TPC) (14.05±4.04, 34.59±3.01 and 18.58±1.87 mg GAEQ/100 mg); the total flavonoid content(TFC) of flower (12.45±1.87, 20.41±2.69 and mg QEQ/100 mg); total terpenoids (TTC) (20.74±2.34, 20.74±2.34 and 15.97±1.19 mg LIN EQ/100mg) of MLB, MLF and MLL respectively. Whereas that of the K. grandifoliola methanol extracts include; TAC (7.32±0.14,8.49±0.34, 10.67±0.22 mg AEQ/100 mg); TPC (37.49±1.40, 44.41±0.69, 53.57±1.50 mgGAEQ/100 mg); TFC (6.54±0.55, 9.58±0.89 and 10.26±0.92 mg QEQ/100 mg); TTC(10.16±1.41, 35.78±2.14 and 23.45±1.76 mg LIN EQ/100mg) of MKL, MKR and MKSB respectively. The major components of essential oil, out of the 71 constituents identified include Davanone D (32.91 %), Caryophyllene (5.07 %), Nerolidol 2 (3.56 %) and GermacreneD (3.13 %). Compounds 3.47 was isolated from the methanol extract of L. camara flowers. This compound is reported for the first time from the L. camara flower extract. Two compounds, compounds 4.23, and 4.26, were isolated from the methanol extract of K. grandifoliola roots, compound 4.22 was isolated from the ethyl acetate root extract while compounds 4.24 and 4.25 were isolated from the ethyl acetate stem bark extract as isomers in a mixture. Compounds 4.22 and 4.23 are reported from K. grandifoliola root for the first time. The isolated compounds (compounds 3.47 and 4.23) were nontoxic to the Vero cell line and this may contribute to possible stimulation of cell proliferation, promoting wound healing. Cytotoxicity describes extract virulence to Vero cell line. MLF and ELB were found nontoxic even at the highest concentration of 200 μg/mL. The MKSB and MKR, as well as the EKSB were nontoxic. Antioxidant activity results, described by the percentage inhibition in the DPPH assay, showed that MLF and MKSB had the highest antioxidant activities compared with the ascorbic acid standard, with IC50 of 38.68±5.09 and 37.03±11.95 μg/mL for L. camara and K. grandifoliola respectively. ELB exhibited a significant anti-inflammatory activity inhibiting NO• radical generation in the LPS-stimulated RAW 264.7 macrophages at concentration ranging from 50 and 100 μg/mL. EKSB and MKR showed significant anti-inflammatory activity at 100 and 200 μg/ml respectively. ELL and ELF demonstrated potent growth inhibition against S. pyogenes with an MIC value ≤ 0.125 mg/mL, while the MICs of the ELB and MLL were 0.5 mg/mL and 2 mg/mL respectively. MKSB and MKR and EKSB extract exhibited an effective growth inhibition against S. aureus with MIC of 1 mg/mL. The growth of S. pyogenes was supressed by both ethyl acetate and methanol extracts of all plant parts tested with MIC ranging from 0.25–2 mg/mL. Conclusion: The potent bioactivity shown in the results of the cytotoxicity, antioxidant activity, anti-inflammatory and antimicrobial activity testing, and the nontoxic singlecompounds of L. camara and K. grandifoliola extracts led to the conclusion that the two plants had wound healing potential. The study therefore confirmed their traditional uses for treatment of wounds.Thesis (PhD) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 202

    An assessment of return to work strategies within the South African financial services industry

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    The purpose of this study was to conduct research into the return to work strategies that were used in the South African Financial Services Industry following the COVID-19 pandemic lockdown. The goal was to understand the motivation for the slow return to the office and to explore what strategies organisational leadership could employ to overcome this resistance. The South African Financial Services Industry represents multiple subsectors that are highly regulated in an age where the digital transformation of industries is common, as are the complexities and risks in integration. The significance of the study is to ascertain the appropriate strategies to encourage employees the return to the office since COVID-19. This study used a quantitative approach. This was achieved in the form of a survey sent to a sample of managers in South African Financial Services Industry using an electronic survey instrument created in Google Forms. One hundred and nineteen financial services managers fitting the criteria responded to the survey. The sampling methodology was both convenient and snowball sampling, non-probability techniques. The findings indicated that there is a relationship between extrinsic benefits received by employees and the return to work. The findings from the study also revealed that a hybrid working arrangement is preferred by the South African Financial Services Industry managers compared to working from home permanently From the study it is recommended that financial services organisations employ a hybrid working model where possible. Another recommendation is that leaders have a clear and transparent communication strategy of transforming the working environment to suit the changes brought about by the COVID-19 pandemic.Thesis (Ma) -- Faculty of Faculty of Business and Economic Sciences, 202

    The adoption of international financial reporting standards and foreign direct investment inflows: the moderating effect of the institutional environment in Africa

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    Globalisation has created a need for an international accounting language to facilitate the smooth flow of trade across countries. In 2003, in an effort to establish a global financial reporting language, the International Accounting Standards Board (IASB) developed a single set of high-quality accounting principles known as the International Financial Reporting Standards (IFRS). Over the last decade, several African countries have adopted IFRS, and Africa has become the second-largest adopting continent after Europe. IFRS promotes improved quality of disclosure of accounting transactions, reduces information asymmetry between preparers and users of financial information, lowers the cost of investing, and breaks down information barriers to cross-border investment. Researchers suggest many benefits of IFRS adoption for macroeconomic indicators such as Foreign Direct Investment (FDI). The reduction in information acquisition and processing costs which translates into the reduction in investment costs, has been cited by most researchers. Researchers have argued, however, that the economic benefits of IFRS in Africa depend on the strength of the institutional environment. They also argue that the Western environment in which the IFRS was developed differs from the African environment. Thus, the universal approach of the IASB may not be appropriate due to the historical, social, economic and political context of African countries. The impact of the adoption of IFRS by African countries requires further examination, particularly as a weak institutional environment confronts many African countries. Three research questions are designed for this study; (1) Is there a significant change in FDI inflows for IFRS adopters in selected African countries after the adoption? (2) Is there a significant change in FDI inflows due to the institutional environment? (3) Does the institutional environment in IFRS-adopting countries moderate the effect of IFRS on FDI in selected African countries? The present study is underpinned by the new institutional theory, the information asymmetry theory, the eclectic theory and the signalling theory, each of which provide reasons why African countries have adopted IFRS. Nine hypotheses are developed, based on the research questions, and tested using the Systems General Method of Moments and the Difference-in-Difference method. The study uses data from 26 African countries, 15 adopting and 11 non-adopting countries, over the period 1996 - 2018. First, the study establishes that the adoption of IFRS positively and significantly affects FDI inflows into the selected sample of African countries. Second, the study concludes that legal enforcement, accounting and auditing standards enforcement, and language origin positively and significantly impact FDI inflows into these countries. Legal origin, however, has a positive but insignificant association with FDI inflows. Third, legal enforcement, historical ties, accounting and auditing enforcement and the quality of the institutional environment are found to moderate the effect of IFRS adoption on FDI inflows. These results indicate that IFRS is a crucial determinant of FDI inflows into African countries, but a supportive institutional environment is needed for African countries to attract FDI inflows after adoption. The results contribute to the accounting and finance literature on FDI into African countries, and may assist the investment community to assess the institutional risk associated with investing in IFRS adopting African countries.Thesis (PhD) -- Faculty of Commerce, Accounting, 202

    African linguistic phenomenology as illustrated through the Setswana language

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    Embargoed. Expected release date 2025.Thesis (MA) -- Faculty of Humanities, Philosophy, 202

    Characterizing shift systems and exploring their effects on sleep and fatigue in South African freight railway operators

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    Embargoed. Expected release date 2025.Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 202

    The effect of the anaesthetics 1 Clove oil and MS-222 on the sedation, recovery, survival, population growth and fecundity of the calanoid copepod, Pseudodiaptomus hessei Copepoda Calanoida under culture conditions.

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    Compared to current live food organisms used in aquaculture, the calanoid copepod, Pseudodiaptomus hessei is smaller and has a superior nutritional value. However, due to their fast and erratic movements, manipulating and counting this species for aquaculture research purposes is difficult. For easier manipulation it is therefore necessary to sedate the copepods. The study aimed to determine the effect of two anaesthetics on sedation, recovery, survival, population growth and fecundity of the calanoid copepod, Pseudodiaptomus hessei, under culture conditions. Male and female P. hessei were exposed to the anaesthetics clove oil and Tricaine Methane sulfonate (MS-222). Twelve replicates of five copepods each were exposedto clove oil at 100, 150 and 200 μL/L, and to MS-222 at 300, 600, 900, 1200 and 1500 mg/Lwith the number of fully sedated copepods being recorded. clove oil sedation only occurredafter 5:23±1:25 minutes in the 100 μL/L treatment while copepods exposed to 150 and200μL/L were anaesthetized within 2:48±0:46 and 0:40±0:07 minutes respectively. Sedation did not occur in MS-222 at concentrations of 300 and 600 mg/L while at 900 mg/L all copepodswere sedated within 4:19±0:41 minutes. Only copepods exposed to 1200 and 1500 mg/L were all fully sedated within 2:26±1:46 and 1:23±0:37 minutes respectively. Clove oil recovery onlyoccurred at 4:40±1:32 minutes in the 100 μL/L treatment while copepods exposed to 150 and200 μL/L recovered at 8:30±1:46 and 12:12±0:59 minutes, respectively. In this study, all MS- 222 treatments showed full recovery at 1:07±0:41 to 1:11±0:41 minutes with 100% survivalrate. The growth development FPN (Final Population Number) for Clove oil, MS-222 and control were not different from the control indicating that exposure to the anaesthetic had no effect on their long-term survival (21 days). The mean clutch size of 34±5 eggs per sac was high compared to other studies on the species. Based on these findings the 150 μL/L Clove oiland 1200 mg/L MS-222 concentrations were the lowest doses of each anaesthetic to induce full sedation within 3 minutes followed by rapid recovery 87 within three minutes without it affecting its short (24 hours) and long-term survival, population growth and fecundity. Basedon sedation and recovery rates, effect on survival, fecundity and growth as well as cost and ease use, the 1200 mg/L MS-222 concentration is the recommended to safely anaesthetize P. hessei.Thesis (MSci) -- Faculty of Science and Agriculture, 202

    A reconceptualised perspective of the six-step financial planning process

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    The globally applied six-step financial planning process which is used by CFP® professionals to provide financial advice is designed to ensure that the financial advice is suitable, based on the needs of the consumer. However, given the diverse cultures in South Africa, this study argues that the six-step financial planning process (as it is currently applied) may not be suitable, as it requires contextualisation based on the unique needs of South African consumers. The various population groups in South Africa have their own sets of beliefs, values and cultural practices, and thus view aspects such as wealth (the creation, preservation and transference thereof), marriage, death and retirement, differently. Thus, financial planners who are not knowledgeable about different cultures, diverse financial needs, or the provisions of customary law, may not be able to provide suitable advice. The primary objective of the study is thus to reconceptualise the six-step financial planning process to be more inclusive, in order to better serve the financial planning needs of South African consumers. A comprehensive literature review was undertaken to provide the context and framework within which the reconceptualisation of the six-step financial planning process could be approached. An investigation of the financial planning environment and the financial planning process was completed to determine how the six-step financial planning process is currently applied in the South African context. Further, an investigation of culture and the cultural dimensions – power distance, uncertainty avoidance, individualism, masculinity, timeorientation and indulgence – was conducted, as it was clear that these cultural dimensions cannot be generalised to all South African consumers, due to the large degree of diversity within the population. It was also determined that there are various factors that contribute towards the cultural diversity of South African consumers, which may influence their financial needs and the type of financial advice that is required. These factors include race and ethnicity, marital regimes, procreation and family structures. To further illustrate the diversity of financial needs of South African consumers, a discussion of Black households and the application of financial planning legislation and customary law was provided. Black households are considered to be under-serviced, historically financially excluded, have low levels of financial literacy, and are mostly collectivist in nature. It is for these reasons that Black households are the focus of the study. Some of the financial needs that vi are common among Black households include land and property ownership, family wealth, family homesteads, lobola capital and ‘black tax’ expenditure. Given that the literature review established how the six-step financial planning process is currently applied, an interpretivist research philosophy was adopted in order to gain a deeper understanding of how the six-step financial planning process should be applied in a South African context. Further, the research approach in the context of this study is an inductive one, as the six-step financial planning process is an existing theory that was reconceptualised by considering the perceptions and experiences of 16 CFP® professionals and 14 Black South African households. A mono-method qualitative research methodology was used, with a single qualitative method of data collection (semi-structured interviews), and a single qualitative method of data analysis (latent content analysis). The findings of the study were used to provide a reconceptualised perspective of the six-step financial planning process which takes into consideration the fact that the image of a financial planner plays an important role when trying to establish a professional relationship with a client. The findings reveal that Black consumers in particular, generally have a negative image of a financial planner, which is influenced not only by their perceptions of a financial planner, but also by their self-perception of their own financial situation. The reconceptualised perspective of the six-step financial planning process also incorporates the finding that discussions around personal finances are considered impolite and taboo among the Black African community, which influences their ability to talk about these topics, trust a financial planner, and establish a professional relationship with them. The findings also reveal that a racial and gender bias exists among Black consumers – they prefer interacting with a White male financial planner, as they perceive them to be more competent and have more experience with finances and wealth accumulation. It was also found that CFP® professionals believe that having cultural awareness and cultural intelligence can reduce bias in the way that questions are asked, so as not to offend the client. Thus, cultural awareness was also incorporated into the reconceptualised perspective of the six-step financial planning process. It was also noted that it is important to ascertain clients’ level of financial literacy during the information gathering stage. Black consumers opined that in this regard, it is the role of the financial planner to both ascertain and ensure their clients’ financial literacy, and to offer financial education to ensure client understanding. vii Although the premise of the study is that South African consumers have unique financial needs due to the high degree of diversity among the population, it was the opinion of CFP® professionals that Black consumers, in particular, do not have unique financial needs – instead, they define their needs differently, have different exposures to financial resources to address their financial needs, and also prioritise and satisfy their needs differently. The prioritised financial needs of Black households (sub-themes) that emerged from both participant groups include the need to make provision for black tax, estate planning, funerals, and property ownership. Black household participants mentioned (to a greater extent than CFP® professionals did) the need to make provision for lobola and initiation schools, as these form part of several traditional ceremonies. The need to make provision for a family home was mentioned by Black household participants but not by CFP® professionals. It was discovered from Black household participants that stokvels are the most common micro-finance tool used by Black consumers, for various reasons. In fact for some, stokvels are preferred over formal financial products because they perceive that they yield a higher return, and others use them successfully to supplement their current provisions. These findings (among others) were incorporated into the reconceptualised perspective of the six-step financial planning process which is presented in this study. This study has made a contribution to the financial planning body of knowledge by presenting a reconceptualised perspective of the six-step financial planning process, and providing new knowledge on each of the associated six steps and their suitability in a South African context. This study also provides justification and evidence for the inclusion of aspects within the sixstep financial planning process that enhance the understanding of cultural diversity and needs of Black households in particular. Justification has also been provided for the inclusion of cultural aspects and diverse needs of Black consumers the in the academic curriculum of FPI and FSCA recognised qualifications, as well as the facilitation and learning outcomes of business and product-specific training that FSPs are required to provide to their representatives. The study findings also have implications for the development of the academic curriculum and assessment materials for CFP® professionals by recognised education providers, the FSCA regulatory examination, and the FPI professional competency examination. In addition, the study has provided evidence for the need to develop financial products, or customise existing financial products, that address the viii needs of Black households – especially culture-specific financial needs such as black tax, lobola and funding for initiation schools. Key words: Black households; CFP® professionals; culture; diverse needs; reconceptualisation; six-step financial planning process.Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 202

    An investigation into the effect of dietary protein and fishmeal replacement in juvenile Yellowtail, seriola lalandi (pisces: carangidae) in a recirculating aquaculture system

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    The yellowtail kingfish, Seriola lalandi, is a carnivorous species, which require high levels 40 Percent of protein in its diet of which a significant portion comes from fishmeal. Fishmeal is usually the main ingredient when formulating a diet for carnivorous fish because of its high protein content, good digestibility and balanced essential amino acid profile. The use of fishmeal in diet formulations has decreased because of high prices and short supply. Aquaculturists have little alternative but to reduce the amount used or replace it with alternative suitable protein sources. This study aimed to contribute to the optimization of protein requirements and fishmeal replacement in the diet of juvenile yellowtail in a Recirculating Aquaculture System RAS. This study was conducted at the marine finfish farm, Kingfish Enterprises Pty Ltd in the East London Industrial Development Zone ELIDZ in a purpose designed RAS. The first experiment investigated the effect of dietary protein level on survival, growth, food conversion ratio FCR and health of juvenile yellowtail in a RAS. Four iso-calorific diets containing different dietary protein levels 38 Percent , 44 Percent , 50 Percent and 56 Percent were formulated. Each diet was fed to three RAS tanks holding juvenile yellowtail 30 fish per tank for 49 days. Dietary protein levels did not influence survival of juvenile yellowtail. Specific growth rate SGR p equal 0.003) was greater in fish fed 56 Percent protein compared to fish fed 38 Percent protein but there were no differences between the 56 Percent , 50 Percent and 44 Percent protein diets. There were no differences in protein efficiency ratio PER between the four diets. FCR decreased with increasing protein level with fish being fed the 56 Percent protein yielding the lowest FCR 1.26 compared to fish fed 38 Percent protein 1.76 p equal 0.003, however, there was no difference between the 44 Percent , 50 Percent and 56 Percent protein levels. The hepatocytes of fish fed high dietary lipid content diet with 38 Percent and 44 Percent protein showed large lipid vacuole zones in the cytoplasm p greater 0.001. Body protein, ash, moisture, and lipid was not affected by different dietary protein levels. In terms of producing a diet with best growth at the lowest cost, a 44 Percent protein diet is considered as optimal for juvenile yellowtail in RAS. The second experiment investigated the effect of partial and full replacement of fishmeal with a mixture of alternative protein sources chicken meal, blood meal, and soybean meal in equal proportions that are more sustainable and less costly. Four experimental diets were formulated to be iso-nitrogenous 44 Percent protein and iso-calorific 19.50 Mg/Kg as follows: 1 a control diet with fishmeal as the only protein source which was the same formulation as the 44 Percent diet used in the first experiment, 2 control diet in which 33 Percent of fishmeal was replaced with the protein mixture, 3 control diet in which 67 Percent of fishmeal was replaced with the protein mixture and 4 control diet in which 100 Percent of fishmeal was replaced with the protein mixture. Different fishmeal levels in the diets did not have an effect on the survival on juvenile yellowtail. Specific growth rate SGR was greater for fish fed 67 and 100 Percent fishmeal p equal 0.017 compared to fish fed 0 Percent fishmeal. There were, however, no differences in SGR between fish fed 33, 67, and 100 Percent fishmeal. Condition factor CF was significantly affected by the interaction between dietary treatment and time with average values lower at the end of experiment compared to the start of the experiment. On day 28 p equal 0.02 and 49 p equal 0.01, CF of fish fed 67 and 100 Percent fishmeal diet differed significantly from those fed the 0 Percent fishmeal diet but 33, 67, and 100 Percent fishmeal diets did not differ from each other . Feed conversion ratio FCR was significantly affected by fishmeal replacement with fish on fishmeal-containing diets showing lower FCRs compared to those on fishmeal-free diets p equal 0.001. Fish fed diets containing 67 and 100 Percent fishmeal had low PER 0.026 compared to fish fed 0 Percent fishmeal. There were, however, no differences in PER between fish fed 33, 67, and 100 Percent fishmeal. Hepatosomatic index HSI was not affected by levels of fishmeal replacement in the diet. Body protein, ash, moisture, and lipid was not affected by partial and full replacement of fishmeal. The results indicate that full replacement of fishmeal 0 Percent diet had the worst SGR, FCR, and PER. The remaining three diets were statistically similar which suggests that a diet with 33 Percent fishmeal produces as good growth, FCR and PER as 67 and 100 Percent fishmeal diets. However, as there were also similarities in SGR and PER for the 0 and 33 Percent fishmeal diets, it is therefore recommended that future studies focus on the region between 33-67 Percent to find the optimal break point for the various growth indicators. This study has provided foundation for the formulation of yellowtail kingfish diet which is suitable for use in a RAS.Thesis (MSci) -- Faculty of Science and Agriculture, 202

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