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Price transmission with error correction representation: an application to the South African Garlic Market
Get PDFThesis (M.Sc. (Agricultural Economics)) -- University of Limpopo, 2024There is a high demand for garlic both from the local and international markets. South Africa and the world as a whole have seen a sharp/significant increase in the consumption of garlic during the Corona Virus (COVID-19) era. South African garlic farmers are subjected to exploitation by middlemen such as retailers and wholesalers. This is usually exacerbated by the lack of market information presented to these farmers. This study attempted to test whether there is indeed price transmission in the South African garlic market or not.
The aim of this study was to analyze price transmission in the South African garlic market. The study was conducted in South Africa. The objectives were to provide a description of farmgate, wholesale and retail prices in garlic markets; to determine correlation between farmgate, wholesale and retail prices; to determine the responsiveness of retailers towards a change in farmgate and wholesale garlic prices in South Africa; to determine the direction of price linkage between the farmgate, wholesale, and retail prices of garlic in South Africa and lastly, to determine price transmission in the South African garlic market. This study was conducted in South Africa following a quantitative approach. Secondary data on monthly garlic prices were sourced from the South African Department of Trade, Industry and Competition (DTIC); Joburg Market; National Agricultural Marketing Council (NAMC); and the South African Department of Agriculture, Land Reform, and Rural Development (DALRRD) covering the periods 2011 to 2021. Error Correction Model was used to analyze price transmission, preceded by Augmented Dickey-Fuller and Phillips-Perron tests for data stationarity. The Granger Causality test was also carried out.
The study found the existence of Granger Causality in the South African garlic markets, with retailers responding quickly to price increases at farm and wholesale levels. The outcomes from Granger Causality test revealed a bidirectional price linkage between farmgate and wholesale prices, whereas there is a unidirectional linkage from the farmers and wholesalers to retailers. Through impulse response functions, the study found that retail prices respond faster to changes in wholesale prices than changes in farmgate prices. Additionally, variance decomposition revealed that wholesale prices are major determinants of retail prices in the South African garlic value chain. Through time series forecasting, the study found that farmgate, wholesale and retail prices in the South African garlic market are likely to continue fluctuating due to risks and uncertainties in the market.
The study recommends that the government strengthens its efforts of regulating garlic markets, including other agricultural markets, in order to ensure a fair distribution of income along the marketing chain. It is further recommended that the government invests in the development of modern infrastructure and processing technology to enhance garlic production levels.National Research Foundation (NRF
Factors affecting growth performance of oreochromis mossambicus in a low technology aquaponic system
Get PDFThesis (M.Sc. (Aquaculture)) -- University of Limpopo, 2024The aim of this study was to enhance fish production in low technology aquaponic systems. Growth parameters and somatic indices were assessed in order to determine the effect of feeding frequency, stocking density and recirculation rate on the growth performance of Oreochromis mossambicus in low technology aquaponic systems. Weight gain (%), specific growth rate (SGR), food conversion ratio (FCR), thermal growth coefficient (TGC), condition factor (CF), hepatosomatic index (HSI), viscerosomatic index (VSI) and survival rate (SR) were assessed for each factor. Haematological parameters were also checked to assess the stress levels of fish under different treatments of feeding frequency, stocking density and recirculation rate. Red blood cell (RBC) count, white blood cell (WBC) count, haematocrit, haemoglobin and serum glucose levels were also assessed for each factor. Water quality parameters (pH, dissolved oxygen (DO) concentration, total dissolved solids (TDS), ammonia (NH3), nitrate (NO3-), nitrite (NO2-) and phosphorus (P)) were monitored over the duration of the experiment. Spinacia oleracea growth parameters (shoot length and the number of leaves), were analysed in order to determine its growth performance when integrated with O mossambicus.
The effect of feeding frequency on the growth performance of O. mossambicus in low technology aquaponic systems was evaluated over a duration of 28 days. The fish were stocked in 500 L fibreglass tanks. The fish feeding frequency treatments were T1 (once daily), T2 (twice daily) and T3 (thrice daily). The highest %WG, SGR, TGC and SR were recorded in T3, which was significantly different from other treatments (p 0.05, ANOVA) in SR were observed between treatments. Mortalities that occurred in each treatment were not related to feeding frequency, they may have been due to handling. No significant differences (p > 0.05, ANOVA) in organosomatic indices (CF, HSI and VSI) were observed with respect to feeding frequency. The health status of the fish was not affected by the different feeding frequencies. Additionally, feeding frequency did not significantly affect (p > 0.05, ANOVA) all the haematological parameters. Different feeding frequencies did not cause any significant changes in RBC count, WBC count or serum glucose. The highest blood performance was recorded at the highest feeding frequency (3 times daily). This suggests better health status of O. mossambicus at the highest feeding frequency, where the fish may have been able to feed efficiently. The pH and DO concentration range were 6.99-7.20 and 5.70-8.60 mg/L respectively. No significant (p > 0.05, ANOVA) differences in pH and DO were observed between different treatments. Water quality parameters remained within acceptable limits for growth of tilapia. NH3, NO3- and NO2- concentrations increased with feeding frequency and the duration of the experiment. This could be due to increasing accumulation of fish waste as feeding frequency increased. Feeding frequency resulted in an increase in P concentrations. This may be a result of increasing accumulation of fish waste in the system. The highest plant growth was also observed in T3. The maximum plant growth in T3 was due to the availability of nutrients in the system for a prolonged period during the day. These results show that feeding frequency had an effect on the growth performance of O. mossambicus in low technology aquaponic systems. The feeding frequency of 3 times daily may be the optimum feeding frequency for the growth of O. mossambicus and S. oleracea in aquaponic systems.
The effect of stocking density on the growth performance of O. mossambicus in low technology aquaponic systems was evaluated over a duration of 28 days. The fish were stocked in 500 L fibreglass tanks. The fish stocking density treatments were low stocking density (1.87 kg/m3), intermediate stocking density (2.50 kg/m3) and high stocking density (3.13 kg/m3). The highest %WG, SGR, TGC and SR were recorded in fish that were stocked in ISD. The lowest FCR was also recorded in fish that were stocked in ISD. A significant difference (p 0.05, ANOVA) by stocking density. Mortalities that occurred in each treatment were not related to stocking density; they may have been due to handling. The highest organosomatic indices (CF, HSI and VSI) were observed in the ISD treatment. This could suggest that the fish had the best condition and best health status. Additionally, the highest RBC count, WBC count, haematocrit, haemoglobin, and serum glucose were observed in fish that were stocked at the HSD treatment. This could mean that the fish stocked at the highest density experienced stress which was reflected in high RBC count, WBC count and serum glucose. The highest blood performance was recorded at the lowest stocking density. This could suggest better health status of O. mossambicus at the lowest stocking density, where the fish were able to focus their energy on feeding instead of stress resulting from crowding and competition for food. No significant differences in pH were observed between different treatments. The lowest DO concentration was observed in HSD. Water quality parameters remained within acceptable limits for growth of O. mossambicus. NH3, NO3-, and NO2- concentrations increased with stocking density and the duration of the experiment. This could have resulted from the increasing accumulation of fish waste as stocking density increased. The concentration of P also increased with the stocking density and the experimental duration. This may be owing to the increasing accumulation of fish waste. The highest plant growth was also observed at HSD. This may be due to the increasing accumulation of fish waste in the system that is directly related to the increasing fish biomass with increasing stocking density. These results show that stocking density had an effect on the growth performance of O. mossambicus in low technology aquaponic systems. The intermediate stocking density of 2.50 kg/m3 may be optimal for the growth of both O. mossambicus and S. oleracea in aquaponic systems. The best fish growth (SGR and FCR) was observed in the intermediate stocking density compared to high stocking density and low stocking density.
The effect of recirculation rate on the growth performance of O. mossambicus in low technology aquaponic systems was evaluated over a duration of 28 days. The fish were stocked in 500 L fibreglass tanks. The recirculation rate treatments were LRR (0.5 L/min), IRR (1.5 L/min) and HRR (2.5 L/min). The highest %WG, SGR, TGC and SR were recorded in fish that were stocked in HRR treatments. The lowest FCR was also recorded in HRR. A significant difference (p 0.05, ANOVA) by recirculation rate. Mortalities that occurred in each
recirculation rate treatment were not related to recirculation rate; they may have been
due to handling. The highest (p < 0.05, ANOVA) organosomatic indices (CF, HSI and VSI) were
observed at HRR. Poor fish health in terms of CF, HIS and VSI was observed in LRR. The highest
(p < 0.05, ANOVA) haematological parameters were observed in LRR. This could be due to fish
stress resulting from the low DO concentrations in the water. The highest blood performance of 3.22
was observed at the high recirculation rate treatment. This could suggest that the high
recirculation rate resulted in the best health of O. mossambicus. No significant
differences(p > 0.05, ANOVA) by recirculation rate. Mortalities that occurred in each recirculation rate treatment were not related to recirculation rate; they may have been due to handling. The highest (p 0.05, ANOVA) in pH were observed between different treatments. The pH remained within acceptable limits for growth of O. mossambicus. The lowest DO concentration was recorded in the LRR treatments. In LRR, the lowest DO concentration was observed. The dissolved oxygen levels in LRR treatment were below acceptable limits for growth of O. mossambicus. Recirculation rate led to a decrease in NH3, NO3- and NO2- concentrations, while experimental duration led to their increase. This could be attributed to the decreasing accumulation of fish waste as recirculation rate increased. The P concentration also decreased with increasing recirculation rate and increased with the duration of the experiment. This could be as a result of the decreasing accumulation of fish waste as recirculation rates increased. The highest plant growth was observed in IRR. The maximum plant growth in IRR may be due to stable DO concentrations and nutrients in the system from the accumulating fish waste. These results show that recirculation rate had an effect on the growth performance of O. mossambicus low technology in aquaponic systems. The intermediate recirculation rate (1.5 L/min) may be optimum for the growth of both S. oleracea and O. mossambicus in aquaponic systems.
A low technology coupled aquaponic systems was used in this study. The incorporation of a sedimenter into the system presents a solution to the build up of solid waste in the tanks and the subsequent water quality deterioration. This can also minimise the constant water exchanges. The optimisation of the coupled aquaponic system can allow higher fish and plant densities without compromising the water quality.The balance of fish and plant ratios can allow for optimal growth of both entities without water quality deteriorations.The choice of the fish and and plant species can also affect the nutrient build up in the water. Fish polyculture and plant intercropping are also functional in the optimisation of they system’s overall production. Optimal feeding frequencies can also be used without worrying about the nutrient build up.Department of Agriculture Forestry and Fishe
Effect of Maize densities on the productivity of intercropped cowpea varieties in Limpopo Province
Get PDFThesis (M.Sc. (Agronomy)) -- University of Limpopo, 2024Intercropping maize and cowpea are among the best cultivation practice to increase the crop yield per unit area. However, the great challenge faced by researchers is finding an appropriate combination of planting density and intercropping pattern to preserve cowpea production when maize population density is high under intercropping conditions. A field experiment was conducted to evaluate the effect of maize planting densities on the growth and yield of intercropped cowpea varieties. Study was conducted at the Aquaculture Research Unit, University of Limpopo during 2022/2023 growing season. Maize variety (PAN7469) was intercropped with two cowpea varieties (Brown mix and Dr Saunders) in a 2×2×2 factorial arrangement in a Randomized Complete Block Design (RCBD) with four replications. The experiment consisted of eight treatments from three factors: two cowpea varieties (Brown mix and Dr Saunders), two maize densities (24 700 and 37 000 plants/ha), and two cropping systems which were sole and intercropping. For cowpea, days to 50% flowering, physiological maturity, plant height, number of branches per plant, canopy width, leaf chlorophyll content, above ground dry matter, pod length, number of pods per plant, seeds per pod, hundred seed weight and grain yield were determined. The data for all measured parameters were subjected to the analysis of variance using Statistix 10.0 version. The analysis of variance revealed that the interaction of maize density and cowpea varieties significantly influenced all growth parameters and yield components of cowpea except above ground dry matter and number of seeds per pod. Cowpea grain yield had the mean range of 0.8 to 0.32 t/ha, and the sole crops produced the highest grain yield than intercropped cowpea. Planting Brown mix variety at 37 000 plants/ha maize gave significantly higher grain yield than planting Dr Saunders at both maize densities. Maize-cowpea intercropping had a Land Equivalent Ratio (LER) greater than one, which clearly showed high productivity and better utilization of growth factors in intercropping than sole cropping. Therefore, the results suggest that the maximum of 37 000 plants/ha maize is suitable for maize/cowpea intercropping and should be adopted by farmers due to biological efficient and economic benefits.Department of Agriculture, Rural Development and Land Refor
Grade 10 learners' scientific reasoning skills in characterising state of matter using physics education technology (PhET) at Seotlong Circuit, Sekhukhune East District in Limpopo, South Africa
Get PDFThesis (M. Ed. (Science Education)) -- University of Limpopo, 2024In Grade 10, learners had difficulty in characterising the three states of matter, solid, liquid and gas. Subsequently, the change in states of matter is too abstract and the behaviour of the particles is microscopic in nature. Due to lack of relevant resources in the school where I am teaching in Sekhukhune East District, physics education technology (PhET) simulations were used to visualise the behaviour of the particles. This assisted learners to track the behaviour of the particles that was too impossible to see with the naked eye. The theory that guided this study was the scientific discovery as dual search (SDDS) which has three tenets: the search hypothesis, the search experiment and evaluating the evidence. The qualitative approach was employed under the auspices of the exploratory case study by Merriam. At the same time, Grade 10 learners (n=40) were purposively sampled. Three instruments were used to collect data such as documents, semi-structured interviews and observations. Furthermore, data were coded using axial coding to come up with a coding scheme. Inductive thematic analyses were employed and themes emerged. The results were evaluated using the literature and theoretical framework, and principal findings were generated as follows: learners were able to exhibit scientific reasoning skills by visualising the behaviour of the particles. Subsequently, through the use of PhET simulations, the behaviour of the particles that were unclear was now visualised by learners. On the one hand, it is now clear that learners exhibit, predict, analyse, interpret, evaluate and make informed inferences when learning states of matter using PhET simulations. On the other hand, they were unable to characterise the states of matter when confronted with the simultaneous use of prediction, analysis, interpretation, evaluation and making inferences. Based on the findings of the study, the following recommendations were made. First, it was suggested that the teaching and learning of states of matter should use PhET simulations to visualise microscopic properties of states of matter. Second, there should be learning intervention that will address the simultaneous achievement of scientific reasoning skills. Hence, future studies should focus on how learners can be capacitated with the necessary knowledge to exhibit scientific reasoning skills concurrently
Effects of alternaria leaf spot (alternaria alternata (fr.) keissi) on the growth, yield and phytochemical profile of moringa oleifera lam
Get PDFThesis (M. Sc. Agriculture (Plant Production)) -- University of Limpopo, 2024.Moringa oleifera is a species of Moringa belonging to the family Moringaceae which has been used for thousands of years in less developed communities. It is a nutrient-rich plant containing a variety of minerals and phytochemicals. Moringa is affected by pests and diseases which affect their growth, yield and phytochemical composition. Alternaria alternata is one of the pathogens that causes Alternaria leaf spot disease in Moringa. The objective of the study was to determine whether Alternaria leaf spot (caused by Alternaria alternata) affects the growth, yield and phytochemical contents of the PKM1 cultivar of M. oleifera. The study was conducted at the University of Limpopo, Plant Pathology Laboratory, and the Green Biotechnologies Research Centre of Excellence. Two main treatments: M. oleifera seedlings inoculated with A. alternata and a non-inoculated control were used. The data collected for growth parameters were plant height and stem diameter. Fresh shoot mass and root length were collected as yield parameters. For the physiological attributes: photosynthetic rate, stomatal conductance, transpiration rate, water use efficiency, and Ci intercellular CO2 concentration were collected. The L*, a*,b*,c* and h values were collected as colour parameters. Lastly, the biochemical compounds (total flavonoids, total phenols, antioxidant activity and chlorophyll). To compare differences in treatment means, paired sample t-test was performed at a 5% significance level using Sigma Stat software 2016 and Graph Prism 5. The inoculated treatment significantly (p0.05) effect on the stem diameter and root weight.
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Inoculation affected the physiological attributes as follows: photosynthetic rate, stomatal conductance and transpiration rate was decreased by 4%, 17% and 4% respectively, while the water use efficiency increased by 10% in comparison to the non-inoculated plants. There was no significant effect on the Ci intercellular CO2 concentration. The colour parameters affected by the treatment were as follows: the mean± standard error of the treatment was higher than the control for the L*, a*, b* and c* values. There was no significant difference for the h value. The inoculation significantly (p<0.05) increased the total flavonoids, phenols and antioxidant activity by 69%, 4% and 4% and decreased, chla, chlb and totchl by, 48%, 43% and 44% respectively. In conclusion, the introduction of A. alternata into PKMI cultivar of M. oleifera influenced its growth and development and altered the physiological and biochemical defence mechanism.FoodBev SETA and the DS
The effects of the Covid-19 pandemic on the management of learning and teaching in rural primary schools : the case of Kgakotlou Circuit, Limpopo Province
Get PDFThesis (MPAM.) -- University of Limpopo, 2024Despite various initiatives by the Department of Education in South Africa to support remote learning during the Covid-19 lockdown, rural primary schools faced significant challenges due to inadequate access to internet and other resources. The study was focused on exploring how the Covid-19 pandemic has affected the management of teaching and learning in selected rural primary schools at Kgakotlou Circuit, in the Limpopo Province. This study was informed by the theory of management as a guiding framework in this study. This study adopted a qualitative research approach and interview methods to explore the effect of Covid-19 pandemic on the management of teaching and learning in selected rural primary schools at Kgakotlou Circuit. Data were gathered from 13 key participants comprising of circuit manager, principals, departmental heads and educators from two rural primary schools. The findings from this research indicated that the national plans were put in place by the Department of Education to adapt with the new normal during the pandemic. The revised Annual Teaching Plans (ATPs) were also established to support the continuity of education during the crisis. Schools also promoted tailored online teaching and learning platforms besides giving learners daily homework and incorporating reading materials. However, lack of adequate resources, inequities in access to technology, lack of school-level planning, and untrained staff and other problems significantly affected the adoption and implementation of remote teaching and learning during the pandemic, especially in rural settings. Another finding suggests that the DBE supplied essential learning and teaching materials, such as revised Annual Teaching Plans (ATPs), Curriculum Assessment Policy Statements (CAPS) documents, learner books, teachers’ guides, DBE workbooks, and other supplementary materials. The rotation system was adopted by schools to accommodate learners while adhering to social distancing requirements, indicating a lack of infrastructural and staffing capacity to support daily attendance. The Annual Teaching Plans (ATPs) was also introduced to ensure continuity of education. However, various challenges faced by teachers during transitioning to virtual systems for training, workshops, and meetings. The key challenges included lack of understanding about the virtual system and the poor connectivity. This study recommends that rural schools should be prioritised in terms of resource allocation and capacity building
Psychological factors involved in the development of serial rapists in South Africa : a mixed-methods study
Get PDFThesis (M.A. (Psychology)) -- University of Limpopo, 2024The serial rape phenomenon has recently gained publicity in South Africa while receiving little academic or scientific attention. Scanty empirical research on serial rape is mostly on the criminological factors, with little attention being paid to the psychological factors. The present study sought to examine the psychological factors involved in the development of serial rapists, including the motivations underlying serial rape behaviour. A mixed-methods research approach, with one part being a systematic review and the other being a case study design, was used in this study. For the review study, only four studies met the inclusion criteria and proceeded to the data-matrix analytical stage. For the qualitative aspect, two male participants who were convicted of serial rape were purposefully sampled and participated in semistructured in-depth interviews. The theoretical propositions case study analytical method was used to derive meaning from the two case studies. Object relations theory was the theoretical framework of choice.
Findings from both studies found a high prevalence of early childhood traumatic experiences in cases of serial rapists. Traumas suffered varied from multiple experiences of psychological, physical, and sexual forms of abuse. Similarly, parental neglect, abandonment, and rejection including punitive parenting were frequently reported. In both studies, the results revealed that serial rapists had a long history of mental health problems. Also, the results exposed that the psychological drive or motive behind serial rape behaviour is related to early childhood traumas that were experienced by the perpetrators. It is therefore conclusive that early attachment disruptions due to complex traumas suffered by some rapists could help explain their serial rape behaviour. Effectively, the present study suggests a need for a multipronged strategy guided by idiographic, intra-psychic-oriented thinking when dealing with cases of serial rapists. Rehabilitation programs targeting only serial rapists’ behavioural problems may not necessarily yield sustainable results. It is therefore recommended that correctional centers integrate tailor-made intrapsychic-oriented therapies within existing rehabilitation programs. The present study proposes a serial rapists’ developmental model that can help in the conception and management of serial rapist
Evaluating farmers' perception towards extension service delivery during the Covid-19 pandemic : a case study of Ga-Mothapo Village, Limpopo Province, South Africa
Get PDFThesis (M. Agricultural Management (Agricultural Extension)) -- University of Limpopo, 2024Agricultural extension plays an important role in enhancing agricultural productivity and food security. The aim of the study was to evaluate the perceptions of small-scale farmers towards extension service delivery during the COVID-19 pandemic from hard lockdown level 5 to 3, to inform policy makers about the current extension service delivery and its challenges in Ga-Mothapo village. However, during the COVID-19 pandemic, restrictions of movement of people were put in place to control the spread of the virus and this created a challenge for both farmers and extension officers to find alternative ways to communicate and work together. The study was conducted in Ga-Mothapo Village, Limpopo Province, South Africa. The sample size of the study was 73 small-scale farmers that was farmers calculated using Cochran’s formula (Cochran, 1977). The primary data was collected through semi-structured questionnaire and face-to-face interviews. The qualitative data was coded with arbitrary numbers that were analysed using statistical package for social science (IBM SPSS) software version 29 (2022). The Likert scale was further used to analyze data that yield descriptive statistics to acquire frequency, percentages, standard deviation, and the mean score. Findings of the study is that majority of small-scale farmers participated in the study were male (56%) and female (44%), 63% of the sample attended secondary school, 72%) of small-scale farmers received financial support in a form of vouchers with a restricted purchase in selected stores. The study also found that information communication technology (ICT) channels were used by small-scale farmers to communicate with customers during COVID-19 pandemic hard lockdowns level 5 to 3. The study recommended the following: the use of Cell phones should be encouraged as primary source of ICT channels to communicate information with the farmers, The Department of Agriculture Land and Rural Development, when supporting farmers in the form of vouchers to buy farm inputs, should not limit the farmers to purchase only to selected stores, furthermore the Government should create a policy that ensures that prices do not go beyond market price and that it should create common storage for small scale farmers.
Nutritional evaluation of insect meals as substitutes for fishmeal in oreochromis mossambicus and clarias gariepinus diets
Get PDFThesis (Ph.D.(Aquaculture)) -- University of Limpopo,2024The aim of this thesis was to investigate the potential of enhancing freshwater fish production through replacement of fishmeal with insect meals.
The effect of dietary full-fat Stinkbug (Encosternum delegorguei) meal on growth performance, blood serum chemistry, liver and intestinal histology, and digestive enzyme profile of Oreochromis mossambicus and Clarias gariepinus was evaluated. The Stinkbugs were purchased from the Thohoyandou Town open market. Five diets were formulated to partially substitute fishmeal at 0, 10, 30, 50, and 70%. The diets were formulated to be isonitrogenous (30% crude protein), isolipidic (12% fat content), and isocaloric (15 MJ/Kg). Oreochromis mossambicus juveniles (4.2 ± 0.3 g) were stocked randomly in triplicates at 15 fish per tank. Clarias gariepinus fingerlings (6.4 ± 1.02 g) were stocked randomly in triplicates at 5 fish per tank. The experimental system used for both species was the same. There was a decline in growth performance indices (SGR, TGC, FI, PER, APDC) with an increase in Stinkbug meal inclusion in both O. mossambicus and C. gariepinus. The decline in growth performance was more evident in inclusion levels above 30% in both species and it was attributed to the poor amino acid profile of the Stinkbug meal and its low (29%) protein content. The organosomatic indices (CF, VSI, HSI) were not influenced (P>0.05) by the inclusion of Stinkbug meal. The AST and ALT levels significantly increased at the highest inclusion level (P<0.05) in both O. mossambicus and C. gariepinus. This shows that an inclusion level above 50% may pose stress to these fish species. However, the liver and intestinal histology showed no significant alterations with higher inclusion levels in both O. mossambicus and C. gariepinus. This showed that the inclusion of the Stinkbug meal in the diets of these two species did not affect their liver and gastrointestinal tract. The digestive enzyme profile (amylase, protease, and lipase) showed that both O. mossambicus and C. gariepinus are probably equipped to utilise insect-based diets. Despite the decline in growth performance, cost-benefit analysis showed that the Stinkbug meal may be a sustainable alternative to fishmeal.
Due to poor amino acid, fatty acid profiles, and the low inclusion level of the Stinkbug meal, it was thus prudent to search for locally available alternative insects to potentially replace fishmeal in the diets of O. mossambicus and C. gariepinus. The Alates termites have a better nutritional profile than the Stinkbug meal and are widely available. The utilisation of the Alates termite meal (M. falciger) based diets was compared between O. mossambicus and C. gariepinus. De-winged Alates termites were purchased from the Thohoyandou Town open market. Diet formulation and experimental set-up were adopted as in the previous chapter. The Alates termite meal replaced fishmeal up to 50% without compromising the growth performance of O. mossambicus and C. gariepinus. The higher inclusion level (50%) in Alates termite meal was partly attributed to its protein content (40.46%) which meets the requirements for O. mossambicus (30%) and C. gariepinus (40%). Moreover, the Alates termite meal recorded an Essential amino acid index (EAAI) (1.87) which was higher than the Stinkbug meal EAAI (0.11). However, at inclusion levels above 50%, SGR, WG, TGC, FI, PER, and APDC significantly declined (P<0.05) in both species. The organosomatic indices followed a similar trend. The ALT and AST levels were not influenced by the inclusion of Alates termite meal in O. mossambicus. On the other hand, these enzymes were significantly (P<0.05) elevated at inclusion levels above 50% in C. gariepinus. This shows that inclusion levels above 50% may impose stress on C. gariepinus. The liver and intestine of both fish species were not compromised even at the highest inclusion level. Normal histological micrographs of the liver and intestine were observed across experimental diets in both species. The cost-benefit analysis showed that substituting fishmeal with the Alates termite meal is economically viable. Defatting the Alates termite meal is recommended before incorporation into fish diets. The major limitation of Alates termites is their seasonal variation. It was thus important to search for an insect that could be harvested throughout the year within the geographical area.
The Soldier termite caste of M. falciger was also used as a potential insect to partially replace fishmeal in the diets of O. mossambicus and C. gariepinus. Unlike the Stinkbugs and the Alates termite, the Soldier termite is one of the insects that is available throughout the year. The Soldier termites were purchased from the Thohoyandou Town open Market. The same experimental diet formulation procedure was adopted as in the previous chapters. Juvenile O. mossambicus (9.70 ± 1.2 g) were randomly stocked in triplicates at a stocking density of 10 fish per tank. On the other hand, C. gariepinus fingerlings (5.3 ± 0.8 g) were randomly assigned their diets in triplicates at a stocking density of 5 fish per tank. The best growth perfomance parameters (SGR, TGC, FI, PER, APDC) were recorded at the 50% inclusion level in O. mossambicus. On the contrary, a decline in growth performance with an increase in the Soldier termite meal was observed in C. gariepinus. Inclusion levels beyond 10% significantly reduced the growth performance and nutrient utilisation of C. gariepinus. The difference in growth performance of these two species was ascribed to their feeding habits. Herbivorous fish species have shown the potential to utilise diets with higher insect meal inclusion levels. The organosomatic indices were not (P>0.05) influenced by the inclusion of Solider termite meal in the diets of both O. mossambicus and C. gariepinus. The study showed that the health status of both fish species was not compromised. Histomorphology micrographs also confirmed the normal health status observed in both fish species. The study further showed that O. mossambicus and C. gariepinus have different digestive enzyme profiles and are differently equipped to digest insect-based diets. Substitution of fishmeal with Soldier termite meal may yield higher profit margins than using fishmeal-based diets in O. mossambicus and C. gariepinus.
The study showed that locally available insects have the potential to replace fishmeal in the diets of two commonly cultured warm freshwater species. The Alates termite meal is recommended to replace fishmeal in the diets of both species. The Soldier termite meal is recommended to replace fishmeal in the diet of O. mossambicus. Defattening of the Stinkbug meal is also recommended before incorporating into the fish diets. Digestion can also be improved through supplementation of Natuzyme50® in fish diets. This study showed that the use of locally available insects in the diets of commonly cultured freshwater species has the potential for higher profit margins in aquaculture enterprises. However, a detailed economic analysis is recommended. This may increase warm freshwater aquaculture production and improve the livelihood of local fish farmers.National Research Foundation (NRF) and the University of Limpopo, Aquaculture Research Uni
Extension communication methods and farm management support during Covid-19 pandemic : the case of smallholder cabbage farmers in Polokwane and Lepelle-Nkumpi Local Municipalities, Limpopo Province
Get PDFThesis (M. Agricultural Management (Agricultural Extension )) -- University of Limpopo, 2024The study presents extension communication methods for cabbage farmers with the
aims to understand how the COVID-19 pandemic has affected the extension
communication methods (ICT tools) through which smallholder cabbage farmers
receive farm management information from their local extension practitioners and
whether farmers socio-economic situation position them to receive farm management
information through the conventional communication media and the current digital
communication tools in Polokwane and Lepelle-Nkumpi local municipalities. The
restrictions on people movement and contacts between people, including farmers and
extension practitioners. Smallholder farmers in developing countries including South
Africa, who depend mainly on the public extension service provider for their farm
management information needs, are no longer receiving the traditional face-to-face
farm management support through individual and group visits. The conceptualization
of adoption behaviour analysis utilized in this study was based on the Düvel
framework. The study objective were; to identify and describe smallholder cabbage
farmers socio-economic characteristics that might influence the communication
methods (ICT tools) they use for receiving farm management information from their
local extension practitioner, to ascertain and describe the communication methods
(ICT tools) through which smallholder cabbage farmers mainly received farm
management information from their local extension practitioner before and since the
COVID-19 outbreak in South Africa in 2020, and also to describe the challenges
associated with the communication methods (ICT tools) through which smallholder
cabbage farmers have received farm management information from their local
extension practitioner since the COVID-19 outbreak in South Africa in 2020. A cross sectional survey approach was used for this study to collect data at one point in time
to achieve the aim of the study. A sample of 81 farmers from the two municipalities
were interviewed using a semi-structured questionnaire. Descriptive and inferential
statistics were applied to analyze the data using SPSS software. The questionnaires
were coded, and the data was entered on a computer using Statistical Package for
Social Sciences (SPSS) version 11.5 software. The software was used for data
analysis. Data were analysed using percentages and, frequency and Chi-square test.
The study findings showed that there is a significant relationship between socio economic characteristic and the communication methods through which farmers
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received information. Furthermore, the results showed that most respondents utilized
ICT tools before COVID-19 as compared to the period of COVID-19. Finally, the
results of the distribution of respondents on challenges associated with the
communication methods showed that most respondents had no challenges utilizing
the communication ICT tools. It is therefore recommended that to accelerate
innovation and improve agricultural practices among farmers, policy needs to address
both the technical and social-economic barriers to adoption as well as the cultural
change. Issues such as reading levels require long term transformation strategies.
Shorter term strategies are therefore required, such as deliberately ensuring that
dissemination methods adopt accessible technologies, which in this instance include
radio and TV. It will be essential for research organisations to match the dissemination
methods with the farmers’ preferences to attain more effective transfer of knowledge
and skills from research to farmer