JOURNAL OF AGRICULTURE, SCIENCE AND TECHNOLOGY <p>The Journal of Agriculture, Science and Technology (JAGST) is a peer-refereed <br />the biannual publication first produced in 1997. It features research articles in <br />Agriculture, Biotechnology, Forestry, Human and Veterinary Medicine, Engineering, <br />Architecture, Information Technology, and Physical and Social Sciences. It also carries current scientific reports and, occasionally, reviews of publications with a <br />scientific orientation. <br />The journal serves as an important tool in the mandate of the University’s Research, <br />Production and Extinction (RPE) Division to facilitate dissemination of research <br />findings. <br />The goal of the Journal is to:</p> <ul> <li>Provide a forum for the University staff and students, and researchers from the region and other parts of the world to participate in the discovery, transmission, <br />preservation and enhancement of knowledge in various disciplinary areas.</li> <li>Contribute towards the University’s goal of integrating teaching and research for effective application and preservation of knowledge and skills.</li> <li>Provide a platform for sound academic discourse among researchers.</li> </ul> <p>To view issues that were published in the past years i.e. before 2010 click this link :<a href="">Previous JAGST issues before 2010</a></p> en-US JOURNAL OF AGRICULTURE, SCIENCE AND TECHNOLOGY SMALLHOLDER DAIRY FARMING CHARACTERISATION, TYPOLOGIES AND DETERMINANTS IN NAKURU AND NYANDARUA COUNTIES, KENYA <p>Kenya's dairy industry is the largest and one of the most successful in Africa. Private sector dominates the sector and milk production is majorly from small-scale farms. Despite the policies in place for the dairy inefficiencies and inadequacies in production and commercialization that differs from farmer to farmer. This study established the smallholder dairy farming typologies and their underlying determinants. The study obtained data from a cross section survey of farmers in Nyandarua and Nakuru counties of Kenya, where dairy activities are predominant. Data was collected from 380 smallholder dairy farmers identified using stratified random sampling. Data analysis was conducted by Principal Components Analysis and Cluster Analysis. Results of Principal Component Analysis showed that the smallholders’ dairy farming differed because of output, land, household assets and infrastructure components. Cluster analysis results indicated three significantly different smallholder dairy farming typologies, i.e., Low resource endowed and lower market oriented, moderate resource endowed and moderate market oriented and high resource endowed and high market oriented. The determinants of smallholder dairy typologies were land factors, years of dairy farming, stock of dairy animals kept, labor engaged, household income, farming assets, dairy output and consumption levels and costs of production. The study recommended policies that would increase access to land through land reform processes, financial accessibility and adequate infrastructure needed by the smallholder dairy farmers.</p> G. O. Otieno K. Muendo R. Mbeche Copyright (c) 2021 JOURNAL OF AGRICULTURE, SCIENCE AND TECHNOLOGY 2021-07-06 2021-07-06 20 1 1 23 ENHANCING PRODUCTION WHILE SAVING WATER THROUGH THE SYSTEM OF RICE INTENSIFICATION (SRI) IN KENYA’S IRRIGATION SCHEMES <p>Water available for irrigation has drastically reduced in recent years, especially in agricultural areas of Kenya, due to climate variability as well as unprecedented expansion of irrigation projects. As a result, any intervention that can save water, while also increasing crop yields and quality of produce is a welcome intervention. This is where the System of Rice Intensification (SRI) comes in. SRI is a technology that changes how rice is grown in paddies, and which increases yields. SRI involves among its practices, the alternate wetting and drying of paddies, wider spacing and transplanting only one seedling per hill as well as mechanical weeding. SRI was introduced in Kenya at the Mwea Irrigation Scheme in 2009, through research, awareness creation and training of various cadres of stakeholders, especially farmers. Starting with just two adopter farmers, adoption of SRI steadily rose to cover five irrigation schemes in Kenya, namely, Mwea, Ahero, Budalangi, West Kano and South West Kano. By December 2017, over 10,000 rice farmers had adopted SRI in the five schemes. The high adoption was driven by positive results. In Kenya, SRI increased rice yields by between 20% -100% depending on variety, while water savings of 25%-33% have been recorded under controlled experimentation. Research on SRI has been conducted by PhD and masters students, thus validating the technology scientifically, showing increased yields and water-saving factors. The effects of SRI on mosquito breeding showed that all mosquito larvae died in paddies under SRI, while they remained alive and multiplied in conventional flooded paddies, showing the technology holds promise for reducing malaria prevalence. Furthermore, SRI produces a harder, better grain which has superior qualities on milling and marketing. Indeed, SRI is a green technology which holds promise for food security, water savings, health and environmental benefits and improved productivity of rice in Africa.</p> B. M. Mati W. W. Nyangau J. A. Ndiiri R. Wanjogu Copyright (c) 2021 JOURNAL OF AGRICULTURE, SCIENCE AND TECHNOLOGY 2021-07-06 2021-07-06 20 1 24 40 ATTITUDES OF FARMERS, TRADERS AND URBAN CONSUMERS CONCERNING CONSUMPTION OF TRADITIONAL AFRICAN VEGETABLES IN TANZANIA <p>Traditional African Vegetables (TAVs) form a significant source of food and nutritional security in rural areas of Sub-Saharan Africa. Consumption of TAVs in the region also plays a major role in providing dietary fiber and other important components in the prevention of chronic and lifestyle diseases. However, the consumption of vegetables per individual is still below the recommended level by WHO and FAO. This study determined the attitudes concerning consumption of TAVs in Tanzania. Descriptive statistics and principal components analysis were used to analyze data. Data was collected from randomly selected 63 farmers, purposively selected 65 traders and 262 consumers in Manyire, Embaseny and Bangata markets in Arumeru District, Tanzania. The results showed that of the eleven attitude statements presented to respondents, five scored over 90% and two over 80% on the positive end of the Likert Scale. Three of the remaining four statements scored over 80% and one over 50% on the negative end of the Likert Scale. These four statements carried negative attitudes and also received negative responses; essentially making them positive attitude statements. It was therefore concluded that farmers, traders and consumers have a positive attitude concerning consumption of TAVs. Factor analysis results showed that health, perception and taste factors were the prime movers of attitudes concerning TAVs consumption among farmers, traders and urban consumers. The health factor was the main prime mover for farmers and traders, and the second one for urban consumers. As consumption of TAVs moves away from the farm to urban markets, the importance of the taste factor shifts from the third position for farmers to the first position for urban consumers. Hence taste was the main driver of attitudes for TAVs consumption in urban areas. However, the importance of the perception factor diminishes from the second position for farmers to the fourth position for traders and consumers. It was therefore concluded that there is need to increase knowledge of health benefits for these crops to a larger population across the board. It is also important to train farmers, traders and consumers on innovative ways of mixing various TAVs varieties during preparation, and cooking techniques to enhance taste.</p> M. M. Kavoi J. J. Kimambo Copyright (c) 2021 JOURNAL OF AGRICULTURE, SCIENCE AND TECHNOLOGY 2021-07-06 2021-07-06 20 1 41 57 ENVIRONMENTAL IMPACT ASSESSMENT OF BIOETHANOL PRODUCTION FROM SUGARCANE MOLASSES IN KENYA <p>Environmental concerns and the increasing demand for transportation energy have led to increased production and utilization of biofuels worldwide. Biofuels are perceived to provide clean and green energy. Globally, bioethanol is the most widely used biofuel. This study considered the production of bioethanol from sugarcane molasses. The production of bioethanol from molasses does not pose threat to food security as molasses is a by-product in the manufacture of sugar from the sugarcane. This study aimed to determine the environmental impacts associated with production bioethanol from sugarcane molasses in Kenya from a lifecycle perspective. The environmental impact categories evaluated included Global Warming (GHG emissions), Acidification, Eutrophication, Human Toxicity, Ecotoxicity and Photochemical oxidant Formation. Data was collected in all stages of the life cycle of bioethanol production. These include sugarcane cultivation, harvesting, transportation, cane milling, bioethanol conversion and wastewater treatment. The data was collected during field visits at Mumias Sugar Company and Spectre International. In the study, an inventory analysis was performed which involved quantification of emissions from each stage using models and emission factors from literature. Emissions were also obtained from Ecoinvent databases for the major processes as well as their supporting processes. Economic allocation was used to partition emissions and resources between molasses and sugar. A life cycle impact assessment (LCIA) was performed in Chain Management by Life Cycle Assessment (CMLCA) software. The characterization method that was used to calculate the environmental impacts of bioethanol was the CML-IA. Low values of Global Warming Potential (GWP), Acidification Potential (AP), Eutrophication Potential (EP), Human Toxicity Potential (HTP) and Photochemical Ozone Creation Potential (POCP) were obtained in this study. Emissions emitted due to fossil fuel use, production and use of agrochemicals were found to be the major contributors to environmental impact. The study recommends use of cane trash, bagasse and stillage as supplement fertilizer and boiler fuel. This will reduce dependency on fossil fuels and chemical fertilizers which impacts negatively on the environment.</p> J. Mbothu U. Mutwiwa B. Eshton L. Abubakar Copyright (c) 2021 JOURNAL OF AGRICULTURE, SCIENCE AND TECHNOLOGY 2021-07-06 2021-07-06 20 1 58 74 FATTY ACIDS COMPOSITION IN SOME TISSUES OF COMMERCIALLY SELECTED FRESHWATER AND MARINE FISHES OF THE KENYAN WATERS <p>Fatty acid composition analysis in some tissues of commercially available freshwater and marine fishes in the Kenyan waters was conducted. Four (4) fish species from Lake Naivasha; Largemouth bass or black bass (Micropterus salmoides), Common carp (Cyprinus carpio), Mirror carp (Cyprinus specularis) and Tilapia (Oreochromis leucostictus) and three (3) species from the Indian Ocean; Red snapper (Lutjanus campechanus), White snapper (Macolor niger) and Rabbit fish (Siganus ludridus)] were sampled and analyzed. GC-MS analysis was performed using a GC Voyager-800 series with Trio-01 MS detector in electron ionization (EI) mode to determine qualitatively the fatty acids composition in fish oils. The study revealed that freshwater fish contain essentially omega-6 (ω-6) fatty acids series of the polyunsaturated fatty acids (PUFA) while the marine fishes have more omega[1]3 (ω-3) fatty acids series. The linoleic acid (LA, C18:2) was the prominent omega-6 (ω-6) fatty acid while the prominent omega-3 (ω-3) fatty acid was docosahexaenoic acid (DHA, C22:6) series. This may suggest that the dietary essential fatty acids available for marine fishes was the omega-3 polyunsaturated fatty acids which may be absent and hence unavailable for freshwater fishes Thus, the marine fish species are better providers of omega-3 fatty acids such as DHA (C22:6n-3) while the freshwater species are better providers of omega-6 fatty acids such as the linoleic acid (C18:2n-6) as well as the arachidonic acid (C20:4n-6). This study reveals that marine fish species contain appreciable levels of ω-3 polyunsaturated fatty acids and would therefore be suitable for the provision of highly unsaturated low-fat diet containing omega-3 fatty acids while freshwater fishes will provide the ω-6 fatty acids. This study however, may not explain whether the ω-3 fatty acids observed in marine fishes are derived directly from the fish diet or the fish species are good converters of the short chain ω-3 fatty acids like linolenic acid (18:3n-3) into EPA and DHA through enzyme controlled de-saturation followed by chain elongation processes.</p> J. M. Keriko C. W. Chege M. M. Magu A. N. Murigi C. N. Matindi P. M. Njogu Copyright (c) 2021 JOURNAL OF AGRICULTURE, SCIENCE AND TECHNOLOGY 2021-07-06 2021-07-06 20 1 75 93 ANALYSIS OF BITUMEN DRAINDOWN CHARACTERISTICS OF SISAL-PLASTIC MODIFIED OPEN GRADED ASPHALT <p>A study was done to determine the feasibility of improving bitumen retention of open graded asphalt (OGA) concrete through the use of sisal fiber and a blend of high-density polyethylene (HDPE) and low-density polyethylene (LDPE) type of waste plastics. Open graded asphalt concrete is made of gap graded aggregate whose sizes range from 6mm to 12mm. The main objective of this research was to determine how sisal fibre can be used to reduce bitumen draindown and effectively utilize waste plastics in construction of flexible pavement to improve strength and performance capabilities. 5mm long sisal fibre of varying proportion percentage ranging from 0.1%, 0.2%, 0.3% and 0.4% were used in preparation of the samples. Further 2-3mm shredded waste plastic was varied from 0%, 1%, 3%, 5% and 7% in another set of asphalt concrete samples. The optimum percentage quantities of sisal fibre and waste plastics obtained at optimum Marshall stability were used in the determination of bitumen draindown. Aggregates were mixed with 5% waste plastics and heated at 170oC until waste plastics coated the aggregates. Thereafter, 0.3% sisal fibre treated with sodium hydroxide (NaOH) was mixed with hot bitumen and coated hot aggregates at 170°C. The resultant mix was analyzed for bitumen retention properties to assess its suitability for road construction. The draindown was found to be 0% for Sisal-Plastic modified samples as compared to 6.5% for control mix. The adoption of the findings of this study will lead to improved road pavement strengths that can bear increasing traffic loads without rutting or cracking. Utilization of waste plastic will help to improve the environment through friendly disposal of waste plastics.</p> T. Mungathia Z. A. Gariy T. Nyomboi Copyright (c) 2021 JOURNAL OF AGRICULTURE, SCIENCE AND TECHNOLOGY 2021-07-06 2021-07-06 20 1 94 106 MOISTURE SUSCEPTIBILITY CHARACTERISTICS OF SISAL-POLYETHENE MODIFIED OPEN GRADED ASPHALT CONCRETE <p>The objective of the study was to evaluate if sisal fibre and polyethene waste plastics can be used in road construction of flexible pavement to improve strength and reduce moisture susceptibility. The indirect tensile strength test is used to determine the tensile properties of the Open Graded Asphalt (OGA) mixture which can be further related to the cracking properties of the pavement. The tensile strength ratio of bituminous mixtures is an indicator of their resistance to moisture susceptibility and a measure of water sensitivity. Clean polyethene waste plastics comprising of High-Density Polyethylene (HDPE) and Low-Density Polyethylene (LDPE) were shred into sizes 2-3mm using shredding machine. The open graded aggregates were heated and shredded plastics effectively coated over the aggregate by heating while mixing. Treated sisal fibres of 5mm length were mixed with hot bitumen. Sisal fibre was treated using 0.5N solution of sodium hydroxide solution (NaOH) at a temperature of 15-18°C, by immersing in a bucket of the solution for 12 hours, then removed and air-dried. Sisal fibre treated with 0.5N solution of sodium hydroxide makes sisal fibre become less porous with high density thus making more rigid asphalt concrete mix. The plastic-coated aggregate was mixed with mixture of sisal fibre and bitumen and the resultant mix was analyzed for tensile strength and moisture susceptibility to assess its suitability for road construction. It was observed that tensile strength of modified OGA increased from 0.44 MPA to 1.23MPa representing 180% increase for conditioned state samples when modified using 0.3% sisal fibre and 5% polyethene waste plastics by mass of dry aggregates. The tensile strength ratio of 99.9% of the Sisal-Plastic modified OGA indicated that the sample is highly impermeable to water as compared to sisal fibre modified or non[1]modified control samples. In conclusion, the use of sisal fibre and polyethene waste plastics in the modification of asphalt concrete for road surfacing will strengthen the road pavements thereby increasing the road service life. Disposal of polyethene waste plastics by utilizing them in road construction will help improve the environment and further their successful application as construction materials in flexible pavement to improve road performance.</p> T. Mungathia Z. A. Gariy T. Nyomboi Copyright (c) 2021 JOURNAL OF AGRICULTURE, SCIENCE AND TECHNOLOGY 2021-07-06 2021-07-06 20 1 107 114