Theses and Dissertations- Doctor of Philosophy

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    Agricultural land use and its implications on household food security in Kisii Central Sub-County, Kenya
    (Egerton University, 2015-09) Kumba, Janepha Kemunto
    Agricultural land is an important resource for farm households as it forms the base for their livelihoods. Therefore, the manner in which households utilize this resource influences to a large extent their food security situation. This study sought to establish the impact of agricultural land use on household food security in Kisii Central sub-County, Kisii County. To achieve this objective the study focused on the following; examination of the various land use activities, assessment of the food security situation of households, establishment of the relationships between agricultural land use and household food security and finally determination of the influence of household socio-economic characteristics on agricultural land use and household food security in the study area. Agricultural land use was conceptualized as consisting of four categories namely; cash crop, food crop, fruits and vegetables and pasture and napier grass while household food security was assessed using Experience-based method. The sampling frame comprised all rural farm households in Kisii Central sub-County within the LH1, UM1 and LM2 agro-ecological zones. The sub-Location with the highest population density within each agro-ecological zone was selected and a stratified random sample of 209 respondents was picked. A structured questionnaire was used to collect data from farm household heads. Data was analyzed using the Statistical Package for Social Sciences (SPSS version 17.0). Descriptive statistics provided statistical summaries while Pearson’s Chi-square test was used to establish the relationship between agricultural land use and household food security and also analyze the influence of household socio-economic characteristics on agricultural land use and household food security. Results from the study showed that agricultural land was allocated as follows; food crop (65%), cash crop (25%) and others (10%). Most households were food secure (77.5%). Cash crop (p=0.000) and pasture / napier grass (p=0.002) were found to be significantly related to household food security. The socio-economic characteristics that had a significant influence on agricultural land use and household food security were the level of education of household head, farm size and household income. The study recommends that efforts should be put in place to boost household income through efficient utilization of the land resource in the production of both food and cash crops in order to ensure household food security within the study area.
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    Agrometeorological information access and adaptation to climate variability nexus: case of smallholder sorghum farmers in Busia County, Kenya
    (Egerton University, 2024-09) Atsiaya, Obwina Godfrey
    Significant losses among Kenyan farmers have been attributed to seasonal patterns and disruptions due to climate change. The provision of agrometeorological information as a countermeasure has been constrained by the accessibility and application of the information in adaptation to climate variability. This study aimed to improve the socio-economic welfare of smallholder sorghum farmers in Busia County by enhancing access to and application of agrometeorological information in climate risk mitigation. The study targeted small-scale farmers who are most vulnerable to climate variability and also focused on a traditional crop which has received limited attention in CSA studies. A multistage sampling technique was used to sample 423 smallholder sorghum farmers. Primary data was collected through face-to-face interviews using a pretested semi-structured questionnaire. A Multivariate Probit model was used to assess the factors influencing farmers' choice for agrometeorological information pathways. A binary logistic model was used to determine the influence of socio-economic, institutional, and climate-related factors on access to agrometeorological information. A Poisson regression method was used to evaluate the factors affecting the uptake of climate-smart agricultural practices. Finally, an Endogenous Switching Regression Model was used to assess the effect of agrometeorological information access, and socio-economic and institutional factors on adaptation to climate variability among smallholder sorghum farmers. The results indicate that sorghum farmers mostly used radio, television extension, and mobile internet as weather information pathways. Farmers were found to implement an average of 2 CSA practices. Literacy was associated with the use of television and mobile internet to access CSA information. Proximity to meteorological stations increases the probability of access to agrometeorological information by 8%. The use of Indigenous knowledge and trust in agrometeorological information increased the uptake of CSA practices by 0.119 and 0.229 units respectively. Failure to adapt CSA was associated with a lower sorghum yield with a projected mean decrease of 0.88 in yield. Similarly, adaption was associated with an income increase of 1.37. The findings of this study reveal the need for sensitizing sorghum farmers on the importance of adopting CSA practices such as drought-tolerant varieties, early maturing varieties, irrigation, water harvesting agroforestry among others to enhance their full-scale uptake, improve yield, and contribute to food and nutritional security. This can be enhanced through policies that strengthen agrometeorological information dissemination to small-scale farmers to enhance accessibility and applicability.
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    Analysis of county government expenditure and county economic growth in kenya
    (Egerton, 2020-03) Gisore, Mose, Naftaly; Gisore, Mose, Naftaly
    e modern devolution development across the globe has been in part driven by assertions of a supposed ‘economic dividend’ linked with the devolved expenditure. There is however, little empirical evidence to validate these assertions in Kenya. Most empirical studies across different countries have used different methods of analysis, different time periods and diverse techniques of measuring variable which have generated mixed conclusions and others are inconclusive. More so, in Kenya these studies do not differentiate between long-run and short-run channels through which county expenditure influences economic activities. The implication in differentiating these two effects arises for the two motives. First, there is interval between a fiscal policy action and its impact in the county economy. Second, they can have opposite effects on growth. Failure to differentiate can give erroneous results and recommendations. It is against this background that this study was carried out to analyse the long-run and short-run effect of components of county expenditure on county economic growth in Kenya using panel data set over the period 2013 to 2017. This study used the published annual data from Economic Surveys, Gross County Product (GCP) report, Statistical Abstracts and county Budget Implementation Review reports. Further, this study was informed by neoclassical augmented Ram growth accounting model as the theoretical framework. The analysis techniques that were used in this study were descriptive and inferential statistics. Employing Harris–Tzavalis (HT) test, this study tested for the panel unit root and found that all variables were non-stationary at their level except GCP per capita, human capital and non-devolved expenditure. To check if the variables have long-run relationship, this study used Kao panel test. The result for this test revealed that there exists a long-run relationship among the real GCP per capita and regressors in the model. Once cointegration was confirmed using Kao test, the long-run and error correction estimates of the panel ARDL model were obtained. The ARDL results revealed that spending on recurrent and rise in absorption rate of expenditure exerts a positive and significant effect on economic growth both in short-run and long-run hence confirming Keynesian theory in Kenya. However, capital expenditure was insignificant during the study period. Arising from the study findings, this study submits that the county authorities need to put in place policies that will improve budget allocation and execution so as to improve expenditure to capital infrastructure in counties. This is because counties typically lack infrastructures such as roads, power, water and communications that boost private productivity and consequently GCP growth.
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    Analysis of Extruded Ready-To-Eat Baby Foods Prepared Using Composite Flours from Orange-Fleshed Sweet Potatoes, Soybeans, and Amaranth Seeds
    (Egerton University, 2023-07) Nkesiga, Jackson
    There is severe food insecurity for many people who live in sub-Saharan Africa. The situation is worse for children under the age of five years who are undernourished. This is caused mainly by poverty limiting access to quality foods, as well as poor breastfeeding, and complementary feeding practices. Therefore, the purpose of this study was to develop and analyze the physicochemical properties, microbial, sensory properties, and shelf-life of extruded RTE baby foods prepared using composite flours from orange-fleshed sweet potatoes (OFSP), amaranth seeds, and soybeans. Ready-to-eat (RTE) baby foods which are conveniently distributed to the poor could be a way of mitigating this challenge. Additionally, there are advocacies for the utilization of locally available food resources for sustainable food production. Extrusion technology has been used in many parts of the world to process RTE foods. However, as with most food technologies, there are always questions regarding optimum working conditions, nutritional quality and safety, consumer outlook, and shelf stability that need to be addressed. The ingredients were optimized using the extreme vertices method of mixture design using Minitab Software. The optimum value for model verification was 57% OFSP, 24% amaranth seeds, and 19% soybeans flour, to achieve targeted values of crude protein (14%), total minerals (4.7%), and Vitamin A (813.6 Retinol Activity Equivalent μg/100g). The optimum extrusion cooking conditions were established as 90oC die temperature, 35% feed moisture content, and 400 rpm screw speed based on Box-Behnken Experimental Design of Response Surface Methodology under Design Expert Software. A completely randomized design (CRD) in a factorial experimental design was employed using statistical analysis software (SAS) for the production of extruded ready-to-eat baby foods. The results revealed that extrusion cooking and blend proportions significantly (p<0.05) affected the physicochemical properties, microbial, sensory properties, and shelf-life of extrudates. The extrusion cooking significantly (p<0.05) reduced moisture content (59.5%), protein content by 5.56%, anti-nutrient content (65.24 - 97.43%), and vitamin A content (21.33%). On the other hand, there were significant (p<0.05) increases in carbohydrate (12.31%), total minerals (10.44%), dry matter (7.06%) contents, energy value (6.38%) and energy-to-protein ratio (11.28%). Blend proportions and extrusion cooking have significant (p<0.05) positive effects on the protein quality of the extrudates in terms of in vitro protein digestibility and available lysine. The shelf-life of extrudates was found to be about 4 to 6 months. Therefore, the use of extrusion cooking techniques for OFSP, amaranth seeds, and soybeans composite flours has the potential for the production of value-added OFSP food products. These findings can be used to achieve food and nutrition security in developing countries.
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    Analysis of Factors Influencing Productivity and extent of Smallholder Commercialization of Green Grams and Pigeon Peas in Machakos County, Kenya
    (Egerton University, 2021-04) Wambua, John Mulwa
    Small farmer commercialization was an indispensable pathway towards sustainable food security based on production specialization of food crops. The common staple food crops in Mwala and Yatta sub-counties which are the main semi-arid areas in Machakos County were green grams and pigeon peas. However, the factors affecting productivity and the resultant output for commercialization are not fully understood. The main objectives were therefore to assess the extent and determinants of the levels of commercialization, estimate the factors affecting productivity of green gram and pigeon pea, determine the effects of productivity and output retention on size of marketed surplus of green gram and pigeon production and assess the factors affecting market performance. A survey method was used during data collection where 364 households and 110 grain traders were sampled. Results shown by the descriptive statistics indicated that, the percentages of subsistence and commercial oriented households, focusing on green gram were 79.1% and 20.9%, respectively. The percentages of subsistence and commercial oriented households, focusing on pigeon pea production were 87.9% and 12.1%, respectively. The mean productivity of green gram in the subsistence, semi-commercial and fully commercial farms were 11.581, 104.474 and 204.439 kilograms per hectare, respectively. Pigeon pea mean productivity was 43.334, 48.25 and 13.708 kilograms per hectare in subsistence, semi-commercial and fully commercial farms. Marketed surplus of green gram was determined by the size of landholding (4.422***), yield of green gram (0.056***), retention for seed and given away (1.027**) and production systems in agro-ecological zones (43.613***). Significant increase in pigeon pea marketed surplus was due to household’s retention for seed (2.064***) and market price of output (1.641***). In terms of market degree of competition, results showed that, few large traders of green gram, about 8.26 % accounted for 78.40% of the total volume purchased. Few large traders of pigeon pea, about 8.27 %, accounted for 72.13%. Therefore, this study concluded that, subsistence level dominated in green gram and pigeon pea production. This could have been influenced by low productivity of green gram and pigeon pea, low household marketed surplus and low market competition. Based on the results, various policy concerns were recommended for transforming subsistence-oriented production into market-oriented production focusing on green gram and pigeon pea food crops.
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    Analysis of microbial infections in Camel (Camelus Dromedarius) milk and implications in Kenya
    (Egerton University, 2007-06) Matofari, Joseph W
    Raw camel milk production and marketing chain in Kenya was investigated for microbial infections and implications. Milk samples were taken using simple random sampling method in a clustered sampling plan. There were three cluster levels, the production, and processing and market levels. Analysis of samples in the laboratory for enumeration and characterization was by standard methods as described in the methodology. Data analysis was done by Pearson correlation coefficient and chi-square. At production level, 66% of the 107 samples taken had bacterial load ranging from 103-105 colony forming units per ml (cfu/ml). Over 90% of the samples from the processing and market levels ranged from 106-108 cfu/ml. The total viable counts were higher (P < 0.05) than coliform counts at production level. There were more spores at production than at market level. All the isolated organisms did not survive temperatures above 550 C. Salmonella enterica was prevalent at production and processing level. There was no S.enterica isolation at market level. Gram-negative rods (GNR) occurred at every level of the camel milk chain with an incidence of 54% of the 254 samples taken. Gram-positive cocci (42% incidence) were highest at production level. From the study, the microbial load in raw camel milk chain increased from production to the market. GNR were the majority and included the general Escherichia, Enterobacter and Pseudomonas. S.enterica contamination of raw camel milk chain exists at production and collection level and not at the market level. The S enterica serovars involved were S. enterica Typhi and S. enterica Paratyphi C. Since camels, pastoralists and camel milk handlers may act as carriers of S. enterica in the causation web, it is recommented that another study be done to determine host specificity for the serovars identified.
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    Analysis of micronutrients and heavy metals of indigenous reed salts and soils from selected areas in Western Kenya
    (Egerton University, 2016-11) Tsikhungu, Phanice Wangila
    Most communities in Western Kenya use plant indigenous salts for cooking, medicinal and numerous uses. Typha latifolia and Cyperus rotundus reeds are widely used in Busia and Lugari regions of Western Kenya to prepare indigenous salts. The suitability of these salts and validation of micronutrients and heavy metals is unknown. The objective of this study was to assess the suitability of the indigenous reed salt used in selected parts of Western Kenya. Micronutrients and heavy metal concentrations in soil habitats, C. rotundus and T. latifolia and reed salts were determined; In addition, the effect of the various methods of processing, storage conditions and the stability of iron and iodine nutrients has been investigated. Iodometric titration (Iodine), 1, 10-phenanthroline method (Iron II), flame photometric method (Na and K) and Atomic absorption spectrophotometric method (Pb, Cd, Fe, Cr) were used for analysis. Results showed that 85% of Lugari and Busia inhabitants in Western Kenya use C. rotundus and T. latifolia reed salts. Heavy metal in the soil was of the order Fe> Cr >Pb > Cd for the dry season and Cr > Fe > Cd > Pb for the wet season both in top and sub-surface soils with higher levels in the dry season. Salt iodine was of the order Kensalt >Top-chef salt > Herbal sea salt > Sea salt > C. rotundus salt > T. latifolia and Herbal sea salt >C. rotundus salt = T. latifolia salt > Sea salt > Kensalt = Top-chef salt for Fe2+. C. rotundus and T. latifolia reed salts had higher iodine (1.1 mg/kg) than the WHO limit of 0.015 - 1.1 mg/kg , while the concentration of Fe2+ (0.9 mg/kg and 1.0 mg/kg) was below the recommended limit of 8 - 45 mg/kg. The Na: K ratio of T. latifolia salt (3.2:1) was within the recommended limit of 2.5:1 - 4:1 while that of C. rotundus salt (0.9:1) is lower. Fe, Pb and Cd levels in both C. rotundus reed and T. latifolia reed salts exceeded the WHO/FAO permissible. Effectively all iodine and Fe2+ present in the reed salts was lost within six months of storage under normal conditions of temperature and RH with more losses at elevated temperature and relative humidity. T. latifolia salt prepared using complete evaporation method and stored in LDPE container for a period not more than three months is suitable for use as table salt. C. rotundus prepared by complete evaporation method is ideal for use as a low-sodium salt.
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    Antibacterial Activity of Chrysanthemum Cinerariaefolium (Pyrethrum) Secondary Metabolites and Green Synthesized Silver Nanoparticles
    (Egerton University, 2022-08) Kosgei, Caroline Jepchirchir
    The development of resistance to antibacterial agents by bacteria, drive efforts in bio prospecting for new novel compounds that can be used to target these resistant microorganisms. Plants are among natural sources of novel compounds with medicinal importance due to their desirable potency. Besides, plant phytochemicals can reduce metal ions to metal nanoparticles hence play important role in the green synthesis of nanoparticles. In the current study, bioactive compounds against selected bacteria were isolated from pyrethrum plant Chrysanthemum cinerariaefolium by carrying out bioassay-guided fractionation. The isolated compounds were characterized using 1D and 2D Nuclear Magnetic Resonance (NMR). Extracts of organic solvents and aqueous of C. cinerariaefolium were also used in the green synthesis of silver nanoparticles (Ag NPs) via reduction of silver ions present in silver nitrate. Synthesis involved mixing a fixed ratio of plant crude extracts with silver ions and storing the mixture in the dark. Observation of a color change to brown signified the formation of the nanoparticles. The nanoparticles were characterized using UV-Vis, Scanning Electron Microscopy, Transmission Electron Microscopy, EDX (energy dispersive X-ray analysis), and Fourier-Transform Infrared Spectroscopy (FTIR). The compounds isolated were (Z)-2 methyl-4-oxo-3-(pent-2-en-1-yl)cyclopent-2-en-1-yl2,2-dimethyl-3-(2-methylprop-1-en-1-yl) cyclopropane-1-carboxylate (jasmolin I), 2-methyl-4-oxo-3(Z)-penta-2,4-diene-1-yl)cyclopent-2-en-1-yl3-(E)-3-methoxy-2-methyl-3-oxoprop-1-en-yl-2,2-dimethylcyclopropane-1-carboxylate (pyrethrin II), and (Z)-2-(but-2-en-1-yl)-4-hydroxy-3-methylcyclopent-2-en-1-one (cinerolone). The compounds showed more activity on the bacteria as a mixture in the ratio of 1:1:1 than individual compounds, with MIC of 25 mg/ml against Pseudomonas aeruginosa. The compounds can therefore be used as lead compounds in drug discovery against bacteria. All the nanoparticles formed were generally spherical in shape. The smallest and largest nanoparticles had sizes of 22.8± 17.5 nm and 75.3± 19.7 nm and they belonged to dichloromethane-Ag NPs and ethyl acetate-Ag NPs respectively. The particles exhibited size-dependent activity on the selected bacteria. Safety studies on the nanoparticles and pyrethrum extracts on Vero cells showed that they were not cytotoxic hence safe for utilization in drug discovery. Pyrethrum plant therefore possesses phytochemicals that can be used in green synthesis nanoparticles. Other plants should be exploited to ascertain their ability to synthesis nanoparticles.
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    Antimicrobial activity and phytochemical studies of turraea abyssinica, meyna tetraphylla and leonotis mollissima
    (Egerton University, 2019-11) Kinuthia, Esther Wanjiru
    Due to the high bills involved in the importation of modern medicinal drugs, about 80% of the African population use traditional medicine from plants to treat common infectious diseases caused by microorganisms. The main objective of this research was to determine the antimicrobial activity of crude extracts and isolated compounds from Turraea abyssinica, Meyna tetraphylla (Abyssinian coral tree) and Leonotis mollissima (Lion’s ear) from Meliaceae, Rubiaceae and Lamiaceae families respectively. They were studied in this research due to their wide use by local communities of Kenya for medicinal remedies. Plant materials were sampled from Kirinyaga East, Narok North, Baringo South, Tharaka Nthi Maua, Laikipia University and Mau Narok in Kenya. They were identified and voucher specimen kept for reference. All the plants crude extracts showed significant antimicrobial activity on all the test microorganism (Bacillus cereus, Staphylococcus aureus, Escherichia coli,Salmonella typhimurium and Candida albicans) at a concentration of 1 mg/ml despite been sampled from different regions of Kenya. They had lower MIC (Minimum Inhibition Concentration) as compared to the Amoxil® and Doxycycline® antibiotics that were used as positive control for comparison. From Turraea abyssinica stem bark dichloromethane crude extract (52.42 g), three compounds 176 (Sitosterol, 4.60 mg), 177 (Scopoletin, 6.00 mg) and 178 [2-(1’,2’ Dihydroxypropyl)tetradecanoic acid, 5.65 mg] were isolated. Of the three compounds only compound 176 showed significant activity on Bacillus cereus, Staphylococcus aureus, and Candida albicans) at a concentration of 2.5 mg/mL to 4.0 mg/mL. Meyna tetraphylla leaves dichloromethane crude extract (45.24 g) gave compounds 179 (Phaeophytin, 9.40 mg), 180 (Enantiomer, 5.80 mg), 118 (α-Amyrin, 5.65 mg) and 60 (Sitigmasterol, 5.82 mg). The Structures of the compounds were elucidated using 1D-and 2D NMR. Experiments. Compound (179) showed significant activity on Escherichia coli and Salmonella typhimurium at a concentration of 4.0 mg/mL while α-Amyrin (118) had significant activity on Salmonella typhimurium at a concentration of 4.0 mg/mL. Leonotis mollissima leaves dichloromethane crude extract (79.69 g) yielded compounds 181 (Sederin, 7.70 mg), 182 (20-hydroxylucidenic acid D2, 7.10 mg) and 183 [(13R)-19α,13α-epoxylabda 6β(19).16(15)-dioldilactone, 21.20 mg]. Only compound (182) showed significant antimicrobial activity on Escherichia coli at a concentration of 0.4 mg/mL. This was a confirmation that the three plants contain compounds that can be isolated and used as drugs to treat various diseases including microbial infectious diseases.
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    Antiplasmodial and toxicity activities and characterization of chemical compounds extracted from selected medicinal plants in Uganda
    (Egerton University, 2018-11) Kodi, Philip
    Malaria caused by Plasmodium parasite is at the moment the one of the highest killer disease in the tropics. In developing countries, where malaria is one of the most prevalent diseases, some people still rely on traditional medicine for the treatment of this disease. In the present study an ethnobotanical survey was conducted to document antimalarial medicinal plants. In vitro antiplasmodial and in vivo toxicity activities were carried out on crude root extracts and on the isolated pure compounds from Oncoba spinosa, Acacia sieberiana and Euclea latideus. Structure elucidation was also carried out on the isolated pure compounds. The ethnobotanical survey was conducted by use of semi-structured interviews and a guided questionnaire. The characterization of the isolated compounds was determined using NMR technique only. The antiplasmodial activity was performed using a fluorescence based SYBR Green 1 assay technique on 3D7 and Dd2 Plasmodium strains. Lorke’s method was used to determine the in vivo acute toxicity of the extracts on mice. Thirty three plant species from 30 genera belonging to 23 families were documented, of these ten species (30.3 %) were recorded for the first time as antimalarial plants. Acute toxicity studies showed that all crude extracts of E. latideus and A. sieberiana had LD50 > 5000 mg/kg. The LD50 for hexane and CH2Cl2 extracts of O. spinosa were > 5000 mg/kg while the EtOAc and MeOH had 547.72 mg/kg. The EtOAc extract of O. spinosa had high activity of (IC50) 3D7: 4.69 ± 0.01 μg/mL and Dd2: 3.52 ± 0.02 μg/mL. Extracts of E. latideus had high activity (IC50) 3D7: (9.75-38.21) μg/mL and Dd2: (2.78-38.93) μg/mL. A. sieberiana extracts had the highest activity of (IC50) 3D7: (4.45-27.32) μg/mL and Dd2: (3.38-21.87) μg/mL. Isolation resulted in the identification of eight known compounds which included; three triterpenoids Lupeol, betulin, 3β-(5-methoxyferuloyl)lup-20(30)-ene; two steroids β-sitosterol, stigmasitosterol; benzoic acid and an aliphatic acid chaulmoogric acid. Betulin and β-sitosterol had the highest activity (IC50) 3D7: 3.71 and 5.51 μM, respectively. Antiplasmodial activities of the extracts (IC50: 2.76- > 50) μg/mL, pure compounds (IC50: 3.71- > 120.77) μM of the three plants and the controls (IC50: 0.0056-0.0440) μg/mL showed significance among themselves at (P < 0.05). Extracts and compounds exerted a significant (P < 0.05) decrease in antiplasmodial activity compared to the standard controls. The findings show that the crude extracts and pure compounds have got high antiplasmodial activity and lack toxicity. Therefore the local communities can continue to use the three plants for the treatment of malaria and this justifies the ethanomedicinal use of the plants for the management of malaria.
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    Antiplasmodial and toxicity activities and characterization of chemical compounds extracted from selected medicinal plants in Uganda
    (Egerton University, 2018-11) Kodi, Philip
    Malaria caused by Plasmodium parasite is at the moment the one of the highest killer disease in the tropics. In developing countries, where malaria is one of the most prevalent diseases, some people still rely on traditional medicine for the treatment of this disease. In the present study an ethnobotanical survey was conducted to document antimalarial medicinal plants. In vitro antiplasmodial and in vivo toxicity activities were carried out on crude root extracts and on the isolated pure compounds from Oncoba spinosa, Acacia sieberiana and Euclea latideus. Structure elucidation was also carried out on the isolated pure compounds. The ethnobotanical survey was conducted by use of semi-structured interviews and a guided questionnaire. The characterization of the isolated compounds was determined using NMR technique only. The antiplasmodial activity was performed using a fluorescence based SYBR Green 1 assay technique on 3D7 and Dd2 Plasmodium strains. Lorke’s method was used to determine the in vivo acute toxicity of the extracts on mice. Thirty three plant species from 30 genera belonging to 23 families were documented, of these ten species (30.3 %) were recorded for the first time as antimalarial plants. Acute toxicity studies showed that all crude extracts of E. latideus and A. sieberiana had LD50 > 5000 mg/kg. The LD50 for hexane and CH2Cl2 extracts of O. spinosa were > 5000 mg/kg while the EtOAc and MeOH had 547.72 mg/kg. The EtOAc extract of O. spinosa had high activity of (IC50) 3D7: 4.69 ± 0.01 μg/mL and Dd2: 3.52 ± 0.02 μg/mL. Extracts of E. latideus had high activity (IC50) 3D7: (9.75-38.21) μg/mL and Dd2: (2.78-38.93) μg/mL. A. sieberiana extracts had the highest activity of (IC50) 3D7: (4.45-27.32) μg/mL and Dd2: (3.38-21.87) μg/mL. Isolation resulted in the identification of eight known compounds which included; three triterpenoids Lupeol, betulin, 3β-(5-methoxyferuloyl)lup-20(30)-ene; two steroids β-sitosterol, stigmasitosterol; benzoic acid and an aliphatic acid chaulmoogric acid. Betulin and β-sitosterol had the highest activity (IC50) 3D7: 3.71 and 5.51 μM, respectively. Antiplasmodial activities of the extracts (IC50: 2.76- > 50) μg/mL, pure compounds (IC50: 3.71- > 120.77) μM of the three plants and the controls (IC50: 0.0056-0.0440) μg/mL showed significance among themselves at (P < 0.05). Extracts and compounds exerted a significant (P < 0.05) decrease in antiplasmodial activity compared to the standard controls. The findings show that the crude extracts and pure compounds have got high antiplasmodial activity and lack toxicity. Therefore the local communities can continue to use the three plants for the treatment of malaria and this justifies the ethanomedicinal use of the plants for the management of malaria.
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    Application of positive deviance concept to assess Amelioration strategies for environmental stresses on Smallholder dairy farms in Tanzania
    (Egerton University, 2023-08) Shija, Dismas Said
    Heat load, feed scarcity and disease infections are prevalent environmental stresses (ES) which either limit or reduce productivity potential of dairy cattle in the tropics. Those prevalent ES impact negatively on production performance of dairy cattle and results in a loss of livelihood benefits from dairying. Among smallholders, a few farmers (positive deviant farms (PDs)) attain consistently outstanding dairy production performance. While majority (typical farms) attain poor performance and loose benefits from dairy cattle. However, literature generally associates outperformance of PDs with husbandry practices being deployed differently from those in typical farms. Empirical evidence is lacking on association of PDs with specific husbandry practices, disease infections, lactation and growth performance. The objective of this study was to contribute to high livelihood benefits from dairying by improving productivity through learning from PDs’ ameliorative husbandry practices under contrasting stressful production environments in Tanzania. The severity of heat load stress on dairy cattle was estimated by temperature-humidity index (THI). A sample of 794 from 3800 smallholder dairy farmers benefiting from the African Dairy Genetic Gains Project was used. Positive deviants were identified based on criteria of consistently outperforming typical farms (p<0.05) in five production performance indicator variables simultaneously: daily milk yield ≥6.32 L/cow/day, energy balance ≥0.35 Mcal NEL/d, age at first calving ≤1153.28 days, calving interval ≤633.68 days and disease-incidence density ≤12.75 per 100 animal-years at risk. The study used a twofactor nested design, with farms nested within the production environment classified as lowand high-stress. Results show that dairy cattle in low-stress environment were exposed to lower heat-stress levels (68.20±0.39 THI) while those in high-stress environment were exposed to mild to moderate heat-stress levels (77.29±0.39 THI). The application of Pareto-Optimality ranking technique complemented with multiple indicator-variable sorting isolated 3.4% PDs and were fairly distributed in low- (n=15) and high-stress environments (n=12). Results reveal significant variations (p<0.05) between PDs and typical farms. Dairy cattle in PDs consistently attained better production performance in low- and high-stress environments. The management practices that differentiated PDs from typical farms were provision of larger floor spacing (13.19±1.94 vs. 6.17±0.37 m2/animal) in high-stress, cattle upgrading, and increased investment in housing, fodder, water and professional health services. These practices can be associated with amelioration of feed scarcity, heat load stresses, and disease infections, and better animal welfare status, which enabled attainment of consistent higher productivity levels in PDs. Therefore, typical farmers should learn from PDs on how to apply husbandry practices effectively to ameliorate feed scarcity, disease infections and heat load stresses.
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    Articulation and Phonological Impairments in the Speech of Second Language Learners in Primary School With Cerebral Palsy: A Case of St Martins Deporre’s Primaryschool, Kisumu County
    (Egerton University, 2018-11) Molenje, Victor Makuto
    The study sought to identify and describe the articulation and phonological impairments in the speech of 6-14 year old learners of English as a second language in primary school with cerebral palsy. Further the study also established the linguistic interventions employed by the teachers to assist the learners affected by articulation and phonological impairments as a result of cerebral palsy. Optimality theory was used to account for the impairments through mapping of competence and performance vis- a-vis input and outputs as shown in the speech samples of the respondents. Further, error analysis provided the procedural methodology for analysis of the speech samples obtained from the subjects. Data was collected from 27 subjects who were purposively sampled from the school population. For purposes of understanding the levels of severity, the subjects were put into three cohorts. A qualitative design with a triangulation strategy was adopted whereby data obtained from the subjects using picture naming tasks and focus group discussion from the teachers, was put in tables and later followed with explanations. Analysis of the speech samples collected from the subjects show the presence of the articulation impairments that include omissions, substitutions, distortions and insertions. The phonological impairments were consonant deletion, cluster reduction, syllable reduction, fronting deafrication, and stopping. Further, findings in this study show that core vocabulary and articulation therapy were the linguistic interventions employed by teachers to help remedy the impairments in the subjects. The findings of this study would be of importance and significance to three groups namely: parents, teachers and researchers. This study also offers both clinical and theoretical benefits. Clinically, data is urgently needed to inform the assessment, treatment and therapy for articulation and phonological impairments in second language learners with Cerebral Palsy. Theoretically, investigation of different varieties of English allows testing of hypothesis based on English speakers
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    Articulation and phonological impairments in the speech of second language learners in school with cerebral palsy: a case of st martins’ deporre’s primaryschool,primary Kisumu County
    (Egerton University, 2018-11) Molenje, Victor Makuto
    The study sought to identify and describe the articulation and phonological impairments in the speech of 6-14 year old learners of English as a second language in primary school with cerebral palsy. Further the study also established the linguistic interventions employed by the teachers to assist the learners affected by articulation and phonological impairments as a result of cerebral palsy. Optimality theory was used to account for the impairments through mapping of competence and performance vis- a-vis input and outputs as shown in the speech samples of the respondents. Further, error analysis provided the procedural methodology for analysis of the speech samples obtained from the subjects. Data was collected from 27 subjects who were purposively sampled from the school population. For purposes of understanding the levels of severity, the subjects were put into three cohorts. A qualitative design with a triangulation strategy was adopted whereby data obtained from the subjects using picture naming tasks and focus group discussion from the teachers, was put in tables and later followed with explanations. Analysis of the speech samples collected from the subjects show the presence of the articulation impairments that include omissions, substitutions, distortions and insertions. The phonological impairments were consonant deletion, cluster reduction, syllable reduction, fronting deafrication, and stopping. Further, findings in this study show that core vocabulary and articulation therapy were the linguistic interventions employed by teachers to help remedy the impairments in the subjects. The findings of this study would be of importance and significance to three groups namely: parents, teachers and researchers. This study also offers both clinical and theoretical benefits. Clinically, data is urgently needed to inform the assessment, treatment and therapy for articulation and phonological impairments in second language learners with Cerebral Palsy. Theoretically, investigation of different varieties of English allows testing of hypothesis based on English speakers.
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    Assessing Farm Level Practices Affecting Milk Production, Quality And Postharvest Losses In Smallholder Dairy And Pastoral Camel Herds Of Kenya
    (Egerton University, 2017-05) Kashongwe, Basole Olivier
    Farm level post harvest milk losses (PHL) in smallholder and pastoral milking herds that occur at milking, pooling, evening storage or at the farm gate delivery may be associated with many farm practices. This study tested the hypotheses that PHL results from milk hygiene practices, that feeding practices influence production and quality of milk, and that milk market outlets influence milk hygiene and PHL. Data was obtained in cross sectional survey, on-farm milk and feed sampling for quality and microbiological tests and targeted on-farm interventions to improve feeding and milk quality. Hypotheses were tested with Chi-square tests, analysis of variance and logistic regression. Mastitis prevalence within smallholder dairy herds was 1.69 times more in rural than in peri-urban farms while prevalence within pastoral camel herds was 1.56 times more in rangelands than in periurban herds. Mastitis positive milk samples had higher incidences of Staphylococcus aureus than of Streptococcus species, both in smallholder (57.9% vs 23.7%) and pastoral (41.6%vs 36.5%) herds. High SCC was associated with high prevalence of mastitis and Staphylococcus aureus. High SCC (≥4x 105cells/ml) was associated with PHL in pastoral (58.8%), in smallholder rural (27%) and in smallholder peri-urban (7%) herds. Feed diversity, quantity and quality (energy and crude protein) offered were better in rural than in peri-urban smallholder herds but had little influence on milk yields. Feeding green forages with crop residues and concentrates attained higher milk yields (10 kg to 14 kg per cow/day) in smallholder herds. Feeding in pastoral herds included Euphorbia tirucalli in the periurban where nutritional quality was better than in rangelands and feeds had influence on SCC and milk composition. Targeted intervention to improve feeding and milk quality in smallholder herds enabled the intervention group to produce 19.9 -19.2% more milk relative to control group, but intervention did not influence change in milk quality. Smallholders participating in both formal and informal markets produced more milk (21.9 kg/day) than those participating only in formal (≤14.7 kg/day) or informal (≤11.3 kg/day) market outlets. Milk quality was generally higher in informal compared to formal market outlets and milk price less than KES 28 a litre discouraged participation in formal markets (p=0.032). These results show that substantial PHL results from milk handling hygiene practices and that feeding practices influence volume and quality of milk produced while markets where farmers sell milk has influence on milk handling hygiene and PHL experienced.
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    Assessing influence of positive deviance and collaborative Learning on improving cassava production and marketing in Nyando climate-smart villages, Kisumu County, Kenya
    (Egerton University, 2023-07) Tana, Paul Ochieng’
    Nyando Climate Smart Village (CSV) is a multi-stakeholder Collaborative Learning Platform facilitated co-testing and co-development of a portfolio of climate smart technologies to empower farmers to respond to changing and variable climate risks. However, field surveys suggested that majority of the farmers have abandoned the technologies, suggesting that only a few could be benefiting with the worsening exposure to climate risks. Though collaborative learning may have failed to empower farmers, a phenomenon pointing to positive deviance behaviour is emerging, indicating possibility of viable solutions being present within local communities by positive deviant farmers who outperform positively compared to the typical majority. This study aimed to understand the influence of positive deviance and collaborative learning on fostering cassava production and marketing in Nyando CSVs of Kenya. The specific objectives were to determine how different typical farmers are compared to positive deviant farmers in adopting, abandoning and knowledge gained from climate smart cassava production and marketing; and how functions of innovation systems and collaborative learning have fostered climate smart cassava production and marketing in Nyando CSVs . The study implemented Participatory Action Research that integrated a household survey, Focus Group Discussion, Key informant interviews and collaborative learning forum (CLF). A sample of 150 farmers were reached out of which, six farmers were identified by peers as positive deviants (PDs) in climate smart cassava innovations. Data analysis was descriptive and inferential with Chi-square tests, logistic regression and best-worst score computation. Positive deviant farmers were distinctively different from typical farmers in adopting, abandoning and realising gains from climate smart cassava production and marketing. Compared to typical farmers, positive deviant farmers replaced local cassava varieties, allocated more land to improved varieties, and improved postharvest handling and cassava value addition. Unlike typical farmers, positive deviant farmers were less likely to abandon climate smart cassava innovations. They also attained relatively higher production, diversification, adaptability, productivity, marketable surplus and food security. Fostering of cassava production and marketing was relatively more important with knowledge development (19.17%), knowledge diffusion (18.86%) and resource mobilisation (14.88%). Collaborative learning had greatest improvement in knowledge about viable cassava seed cuttings, use of inputs, intercropping cassava with other crops, value addition and linkage to processors. These results demonstrate that positive deviance and collaborative learning can foster cassava production and marketing in Climate-Smart Villages. The study recommends strengthening extension service linked to farmer networks and proactively involving positive deviant farmers in promoting climate smart cassava innovations to empower farmers better against climate related risks.
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    Assessing Prevalence of Endometritis and Associated Influence on Performance of Smallholder Zero-Grazed Dairy Cows in Gasabo District of Rwanda
    (Egerton University, 2021-05) Nyabinwa Pascal
    Endometritis is a uterine disease that interrupts cow reproductive cycles as a clinical (CLE) or subclinical (SCLE) condition between 21st and 90th days postpartum (dpp), resulting in suboptimal fertility, production and profitability in a herd. This study tested the hypothesis that suboptimal fertility and production performance of zero-grazed dairy cows on smallholder farms result from prevalent CLE and SCLE cases and multiple risk factors (RFs) at the cowand herd levels. The specific objectives were to determine: farmer perceived and observed endometritis prevalence; farmer perceived effective management interventions (MIs); risk factors; and endometritis influence on milk yield (MY) and reproductive performance. Sample farms (n=370) in Gasabo District of Rwanda were accessed through exponential nondiscriminative snowball sampling in a cross-sectional survey. Zero-grazed dairy cows (n=466) in their 21 to 60 dpp were diagnosed for CLE and SCLE cases using Metricheck device and Cytotape, respectively, and prospectively observed for fertility performance up to 210 dpp, and MY for 30 days post-endometritis diagnosis. Data analysis used the Best-Worst Scaling choice method to determine effective MIs, path analysis model to determine RFs, and general linear model to determine influence of endometritis on MY and reproductive performance. Endometritis prevalence was 3.2% by farmer estimation, but 70.2% observed at the cow-level with 67.2% CLE and 31.8% SCLE while observed prevalence at herd-level was 71.1% with 68.1% CLE and 34.4% SCLE. Of the MIs (n=20) assessed, 60.0% were farmer perceived as the most effective prevention and control. The top four MIs were consulting animal health service (ANHS) providers, not sharing equipment between farms, keeping cows in a clean and dry shed, and selecting sires for calving ease. Some cow- and herd-levels RFs were specific for CLE or SCLE cases and some others were common for both CLE and SCLE cases in smallholder zero-grazed dairy cows. Compared to cows’ negative for endometritis, the positive cows had longer days to first oestrus (median 85 vs 63 days), longer days-not pregnant (95.5 vs 63.0 days), lower pregnancy rate at first service (16.5% vs 32.7%), more services per pregnancy (1.3±0.1 vs. 1.1±0.0) and more anoestrus postpartum cows (48.4% vs. 11.7%). The milk loss during period of discarding was 7.3 ± 0.3 while decrease in MY resulting from endometritis was 1.4 ± 0.2 litres /cow/day. It is concluded that a combination of Metricheck device and Cytotape could optimise detection of endometritis, implementation of MIs reduces RFs and improves reproductive performance while treating endometritis positive cases using veterinary drugs having no residual effect in treated cows could be an alternative to minimise MY loss and associated economic loss.