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Item Evaluation of the moringa oleifera leaf meal effects on milk yield, milk quality and the helminthic load of saanen dairy goats in rangeland conditions at Neudamm farm(University of Namibia, 2024) Shea, Immanuel M.K.Capra aegarus hircus (Goats) are popular small ruminants kept mainly for meat and milk. Over time, goat milk became popular and a substitute for cow milk. Researchers have focused their studies on alternative and cheaper methods of increasing milk yield, milk quality and improved animal health. This study aimed to assess the effects of Moringa oleifera inclusion in the diet of Saanen dairy goats on their milk yield and quality as well as the reduction of gastrointestinal parasite egg load. The study used a 3x3 Crossover Latin square Design to determine the effects of 0g, 10g and 30g/day Moringa oleifera leaf meal on the milk yield and quality whilst a completely randomised design was used to determine the effects on the parasite egg load. The evaluation of milk yield was done by hand milking the goats daily, whereas milk quality was conducted using a Lactoscan SP. The parasite egg load was assessed using the quantitative faecal flotation method complemented by the McMaster Egg Counting Technique. The Statistical Package for Social Science (SPSS®) version 27 (IBM, 2020) software was used for data analysis. Milk yield and quality data were analysed using the General linear model and the parasitic egg counts were analysed using the generalised linear model (Poisson regression model). The comparison of means was done using Duncan’s new multiple range test at P<0.05 significance. The goat milk yields significantly differed at P<0.05 in the first period at 3.178 kg/day (30 days) and the yield reduced in the second at 2.848kg/day and 2.831kg/day for the third period (30 to 90 days of the trial). The moringa supplement had no significant effect on the goat milk yield. The treatment did not affect the milk fat, non-fat solids, density, protein, lactose, added water, temperature, freezing point, salts, total solids or pH of ii the goat milk. The gastrointestinal parasite egg load assessment found the presence of three genera; Strongyloides, Moniezia and Coccidia. The study treatment levels of 10g and 30g of moringa leaf meal/day were effective in the reduction of the egg loads. In conclusion, the study findings showed no positive response in the milk yield and milk quality for the treatment levels of 10g and 30g/day, however, a positive response of parasites to moringa leaf meal was observed due to the reduction of parasitic egg load with 10g and 30g/day treatments. The results from this study show that moringa leaf meal could be used in Saanen dairy goats in the reduction of gastrointestinal helminths. This study would recommend the use of 10g/day moringa leaf meal supplementation for dairy goats for ecological management of gastrointestinal tract parasitesItem Optimization of biodegradation and nutrient release in food waste and goat manure vermicompost amended with seaweed-biochar(University of Namibia, 2021) Katakula, Asteria Aili NdiipohambaVermicomposting has been gaining momentum as a technology capable of generating a nutrient rich organic fertilizer. However, for effective nutrient release, there is need for the optimization of this biological process to allow repeatable production of organic nutrient sources. This study aimed to generate an optimized vermicompost produced from food waste, goat manure and seaweed biochar. This study was guided by the following specific objectives, (i) to characterise biochar produced from two seaweed species at different pyrolysis temperatures (ii) to optimize different combination of Food Waste (FW) and Goat Manure (GM) vermicompost (iii) to optimise the seaweed biochar incorporation into food waste-goat manure mixtures for enhanced biodegradation and nutrient mineralization. Biochar from G. funicularis had the highest macro elements with a total of C 38.3%; N 4.3% and P 6.3 g/kg contents, whilst L. pallida had the highest cations. A pyrolysis temperature of 400°C resulted in the best quality biochar in terms of macro elements, pH, and total C. G. funicularis biochar had significantly higher nutrient concentrations with a great potential for soil quality improvement. The 75 FW: 25 GM and 50 FW: 50 GM vermicompost combinations had significantly ( P ≤ 0.05) the highest final concentration of Olsen phosphorus of 0.98 and 0.96 g per kg of compost, respectively. Biochar incorporation of 4% may be the most optimal, as it enhanced biodegradation and nutrient release than all other treatments with biochar incorporation. Our study clearly indicated that local Namibian waste biomass can be used to develop nutrient rich organic fertilizer. However, the study was done under laboratory conditions further studies will need to evaluate the actual amount of beach cast biomass harvested as well as food waste produced in various industries in order to assess the actual feasibility of producing such fertilizers in practical terms.Item Assessment of farmer preferences, constraints and angro-morphological variation among Bambara groundnut (Vigna subterranea (L.) Verdc.) accessions as a basis for seed yield selection index(University of Namibia, 2020) Valombola, Johanna ShekupeBambara groundnut (Vigna subterranea (L) Verdc) is an orphan, underutilised and less exploited crop in Africa and beyond, Yet, it is an essential traditional crop for the majority of local farmers. The first step in preparing such local germplasm for possible pre-breeding is to undertake a needs assessment study to find out what farmers have on their farms and what they would rather have as an improvement. After that, a pre-breeding program with appropriate breeding goals and objectives can be formulated. Currently, in Namibia, a pre-breeding or breeding program is yet to be put in place. Thus, objective one of this study was to investigate, using a survey instrument, constraints encountered by Bambara groundnut farmers and the farmers’ preferred morpho-types that can be used in the breeding program. The ethnobotanical study was first done across five regions, targeting some key constituencies. Data were collected on varieties, descriptors, uses, preferences, crop improvement status, seed source, and production challenges. Chi-square test showed significant differences among farmers’ preferences (P ≤ 0.05) and crop improvement status (P ≤ 0.05). The results also showed that farmers faced challenges, including susceptibility to insects and the use of low yielding, unimproved cultivar. Results further indicated that many farmers had different Bambara groundnut preferences, such as large seed size and high yield cultivar. The second objective focused on the evaluation of local and exotic Bambara groundnut germplasm. Twenty-five Bambara groundnut germplasm accessions were characterised and evaluated for diversity, using qualitative and quantitative traits. The experimental design was square lattice design replicated three times. For qualitative descriptors, data collected included seed eye colour pattern, seed coat colour, seed pattern, pod shape, pod colour, and pod texture. The Shanon Weiner Index showed high diversity, with an average value of 0.92. Also, a dendrogram indicated five clusters of similarity. Quantitative data were analysed using multiple analysis of variance, Pearson correlation moment, Principal Component Analysis (PCA), and dendrogram. Analysis of variance (ANOVA) indicated significant differences (P ≤ 0.05) among accessions for the number of pods with two or more seeds, seed length, seed width, fresh pod weight per plant, dry pod weight per plant, 100 seed weight, shelling percentage, and harvest index. Other variables that were highly significant (P ≤ 0.01) included the number of pods per plant, pod yield, seed yield, plant height, terminal leaflet width, terminal leaflet length, number of branches, fresh biomass, and dry biomass. Dendrogram sub-criterion indicated three clusters suggesting that few accessions were dissimilar, which was confirmed with Principal Component Analysis, showing that germplasm accessions with common traits were grouped into the same quadrant. For meaningful progress, crop breeding hardly focuses on a single trait at a time. Since crop yield is a polygenic traits, some breeders nowadays use a selection index technique for yield improvement. In this study, a selection index was constructed using yield traits as seed yield, biological yield, dry pod weight per plant, and fresh pod weight per hectare. The index based on three traits, namely seed yield, dry pod weight per plant, and fresh pod weight that had a GA of 41.23% and selection efficiency of 376%. This selection method for seed yield appears to be more effective and efficient compared to the conventional method, the straight selection method.Item Comparing efficiencies of flood and drip irrigation methods in onion production under farmer's production conditions in Omusati region, Namibia(University of Namibia, 2018) Kandongo, HortensiaThe study was conducted in 2015 at Ogongo Campus of the University of Namibia (UNAM) to compare efficiencies of flood and drip irrigation methods, normally used by small scale farmers in the Omusati Region of Namibia, at three different irrigation levels of 100, 80, and 60% Crop evapotranspiration (ETo). Irrigating at lower levels than full irrigation is also referred to as deficit irrigation. Furthermore, the study compared gross margins and assessed yield and growth indicators under the two irrigation systems using onion as the crop. A split-plot in a randomized complete block design (RCBD) experiment was carried out on a 43 m*34 m plot with soil physical and chemical characteristics analyzed before cultivation. The results indicated that 60% of ETo had a higher water use efficiency (WUE) of 4.6 kg m-3 in drip irrigation than 2.8 kg m-3 for the flood. At 80% level, water use efficiency of drip was 3.6 kg m-3 compared to 2.1 kg m-3 for the flood. At 100% levels, the water use efficiency was 2.9 kg m-3 for drip compared to 1.8 kg m-3 for the flood irrigation method. WUE is significantly different at all three levels of irrigation (p =0.008) and also significantly different for the irrigation type (p = <.001).The total volume of water used under the drip irrigation system was less compared to flood irrigation system by 32.3%. Results also show that there was a saving of water in drip irrigation by a margin of 30.7% for the 100% levels, by 33.3% each for the 80 % and 60% levels. As for moisture content, drip irrigation at 100% was better than flood at 100% by 0.74% whist at 80% drip was better than flood by 1.14%, and at 60% drip was better than flood by 0.03%. The yield productions of all treatments were highly significant at 0.4, 0.29 and 0.19 eta squared. The irrigation type was highly significant (p< 0.001). Irrigation level at 20wt is (p=0.008), irrigation level at 10 wt. is significantly different at (p <0.001) and at 5wt, it is also highly significantly different at (p<0.001). However, the interaction between level of irrigation and irrigation type are not significantly different at 20wt (p=0.415) and 10wt (p=0.224). Results show that more yields were obtained in drip irrigation by a margin of 5% for the 100% levels, by 9.4% for the 80 % levels and 9.5 % for the 60% levels. However, plant height/growth rate was not significantly different at all the three levels (p =0.397) of irrigation. A higher growth rate was obtained in drip irrigation treatment by a margin of 28.36% for the 100% levels, by 3.65% for the 80 % levels and 22.38 % for the 60% levels. In addition, the results showed that the gross margin for drip at 60 ETo was higher than for flood by 44.7%, while at 80 of ETo, the gross margin for drip was more than for flood by 64.6%. The gross margin is highly significantly different at all three levels of irrigation (p =0.001) and also significantly different for the irrigation type (p = <.001). The present study suggests that the small scale Namibia farming community should adopt deficit drip irrigation method instead of the old traditional flooding methods.Item Effects of green manure cover crops on weed population, peal, millet and maize productivity under conservation agriculture in Liselo and Mashare Namibia(University of Namibia, 2019) Simon, Amali SimonSmallholder farming communities of northern Namibia are generally cash-constrained and theyare situated in marginal areas where poor soil fertility and land degradation are predominant. They find it difficult to purchase mineral fertilizers and herbicides. There is therefore a need to identify cropping systems that are affordable and can improve their productivity. The integration of green manure cover crops (GMCCs) as rotational crops has been investigated to great lengths in Latin America and reported to improve productivity but information on their use is still scarce in Namibia. Two experiments were set up at two sites, Mashare Irrigation Training Center (MITC) and Liselo Research Station (LRS) having contrasting soil types to investigate the effects of rotating pearl millet and maize with different GMCCs on pearl millet, maize productivity and weed populations over two seasons 2016/2017-2017/2018. In the first experiment, nine different GMCCs were rotated with pearl millet, while maize was rotated with nine GMCCs in the second experiment and their effects in the succeeding season were compared with pearl millet and maize monocropping. At MITC, the highest total weed density was observed in the pearl millet-pigeon pearotation treatment with 3500 weeds ha-1 in season 1, P=0.0371 and 6400 weeds ha-1, P=0.0451 in season 2. The lowest weed density was observed in the pearl millet-lablab treatment with 1300 weeds ha-1and P=0.0371 in season 1 and 2100 weeds ha-1and P=0.0451 in season 2. At LRS, the highest total weed density was observed in the maize-pigeon pearotation treatment with 3200 weeds ha-1and P=0.0433 in season 1 and 3300 weeds ha-1and P=0.0198 in season 2. While, maize-velvet bean rotation treatment had the lowest weed densities of 900 weeds ha-1and P=0.0433 in season 1 and 1000 weeds ha-1and P=0.0198 in season 2. Lablab gave the highest biomass yields as high as 12 t ha-1 both seasons P=0.5929, P= 0.4820 at MITC and at LRS velvet bean yielded up to 10 t ha-1 and P=0.9143 in season 1. The highest plant available nitrogen was produced by jack bean (900 ppm) and P=0.0000 at LRS. Maize grain and biomass yields were significantly P=0.0172affected by different rotations at LRS in season two with maize after maize monocropping attaining the least grain yield of 2.4 t ha-1. In conclusion, rotating pearl millet and maize with cover crops has more noticeable benefits as compared to monocropping and no cover crop could offer all benefits hence this call for identification of niches and a suitable cover crop for that specific niche.,Item Effects of selected conventional and conservation agriculture on soil moisture content, infiltration and maize and pearl millet grain yield in Liselo and Mashare: Namibia(University of Namibia, 2019) Kudumo, Ladislaus P.This study focused on the results from the 2016/17 and 2017/18 cropping seasons from two trials, one in Liselo and the other in Mashare in the Kavango East and Zambezi regions of Namibia, respectively, on the effects of Conventional and Conservation Agriculture (CA) practices and principles on soil moisture content and infiltration. Conventional mouldboard ploughing (CTa), Sub-soiling with a Magoye ripper (SS-M) and Manual direct seeding with a Dibble stick (MDS-M) were the primary treatments of interest in the CA Systems Trial. In Both seasons, average soil moisture content, total water infiltration and runoff were not significantly affected by tillage systems treatments. The treatments of interest in the Component Trial were Conventional tillage (CT), Minimum tillage (MT), Minimum tillage, mulch (MT-M), Minimum tillage, rotation (MT-R) and Minimum tillage, mulch and rotation (MT-MR) were. Significant differences (p=0.000) were observed with regard to soil moisture content in the 0-30cm and 0-60 cm soil depths on the Component Trial at both sites.MT-M plots had the highest soil moisture content of 14.5mm and 39.8mm at Liselo Research Station (LRS) and 44mm and 134.5 mm at Mashare Irrigation Training Center (MITC) for the 0-30cm and 0-60cm soil depths, respectively over the study period. Conventional Tillage (CT) with a mouldboard plough in both localities LRS and MITC had lower average soil moisture content in both 0-30cm and 0-60cm soil depths than most CA treatments. Regarding the Component Trial, a significant difference on grain yield was only observed at MITC in the first season (p=0.0496) and in the second season at LRS (p=0.0206). CT(1783.0 kg ha-1) had the highest pearl millet grain yield, followed by MT-M (1562.0 kg ha-1) and MT (1520.8 kg ha-1) had the lowest pearl millet grain yield. CT (3852.3 kg ha-1) had the highest maize grain yield and MT (2524.0 kg ha-1) had the lowest maize grain yield. Results suggest CA has the potential to increase water conservation and contribute to reduction of risk of crop failure, as was observed at MITC where CA plots had more soil moisture content than conventionally tilled plots.Item Appropriate harvesting stage of sweet-sterm sorghum (Sorghum bicolor (L) Moench) cultivar for optimum bio-ethanol production in Namibia(University of Namibia, 2017) Asuquo, Sylvester OkonThere has been growing global concern over dwindling fossil fuel supply. This development has led to increased interest in exploration of alternative energy sources, especially bio-fuel. Sweet sorghum (Sorghum bicolor), sugar cane (Saccharum officinarum), corn (Zea mays), wheat (Triticum aestivum), rape seed (Brassica napus), barley (Hordeum vulgare), sugar beet (Beta vulgaris), cassava (Manihot esculenta), oil palm (Elaies guineensis), sweet potato (Ipomoea batatas) and many more have been recognized as feedstock crops for bio-fuel production. Like most bio-fuel crops, sweet stem sorghum has the potential to reduce carbon emissions. In addition, this crop shows stronger tolerance than other crops under hot and dry climatic conditions. Its bagasse can be exploited as a by-product including burning, material for electricity generation, paper or fibre board manufacturing, silage for animal feed or juice for ethanol production. While there is abundant availability of sweet stem sorghum in Namibia, its potential as feedstock crop for bio-fuel has not been fully explored. One of the major problems associated with sorghum as a feedstock crop for bio-fuel is the issue of knowing the right harvesting stage for optimum brix sugar yield. In Namibia, great potentials exist for the development of the energy sector through adoption of bio-fuel production. Therefore, this study aimed at ascertaining appropriate harvesting stage of sweet-stem sorghum (Sorghum bicolor (L) Moench) cultivar for optimum brix sugar yield for bio-ethanol production in Namibia. Two trials (February to June 2014) and (October 2014 to February 2015) were conducted in the demonstration plot of the University of Namibia (UNAM), Hifikepunye Pohamba Campus. A total of six harvesting stages (booting stage, and one after every week for five weeks) were used to determine the following response variables: plant height, stem diameter, stem biomass, percentage juice extract, and percentage brix sugar. Data obtained were analyzed using SPSS statistical software and inferences were made at p = 0.05. Mean plant height at 50 % booting was 74.9 cm in trial I and 73.7 cm in trial II with respective coefficients of variation of 20.3 and 21.0. The t-test analysis for plant height was not significant (f = 22.5, p = 0.05). Mean stem weight was 71g in trial 1 (dry season) and 65g in trial 2 (raining season). Mean brix value of the extracted juice was 9.8 % in trial I and 11.8 % in trial II, with coefficients of variation of 5.0 % and 14.5 % respectively. The brix value increases significantly until it peaked at 5 weeks after booting. The study confirms that sweet stem sorghum IS 2331 cultivar could be grown in both dry and wet seasons in the study area. They could be harvested for optimum brix sugar yield for bio-ethanol production at five weeks after booting. Therefore, the study recommends that the Namibian government should raise awareness among crop farmers of the potential of growing sweet stem sorghum in both dry and wet seasons. Future studies should determine the brix sugar yield beyond 5 weeks after booting until possible grain harvest stage.Item The influence of Acacia Mellifera on soil fertility, herbage quality and composition and sandy soils in camel-thorn savannas of Namibia(2013) Nzehengwa, James M.Acacia mellifera is viewed negatively due to its invasive nature to the extent that farmers tend to remove it from their farms without really considering that it may have beneficial effects. Thus the study looked at the role it plays on soil fertility, herbage quality, and botanical composition with reference to N-fixation. Soil and grass samples were collected at Corsica Resettlement farm at 6 distances within three sub-habitats from bases of five A. mellifera trees outwards. The nutrient concentrations of soil (Total N, % of Organic, Ca, K, Cu) and that of herbaceous plants (N, Ca, P, K, Cu) were found to be significantly higher (p<0.01) under tree crown zone than other sub-habitats and decreased along a distance gradient from A. mellifera tree outwards. This is attributed to biological N fixation, shading, litter, ‘nutrient pump’ and decomposition of roots and nodules. Soil Mg and P and plant Mg, Mn and Zn concentration did not significantly differ among sub-habitats. Amounts of plant N, Ca, K increased with amounts of soil N, Ca, K. Herbaceous species composition varied significantly among sub-habitats, with at most 85% similarity between areas under trees and those outside the tree crowns. Perennial grasses (Stipagrostis uniplumis and Stipagrostis ciliata) were commonly found in all clusters, while forbs only occurred under the tree crown zone, leading to the observed differences. The study confirms that A. mellifera enriches the soil fertility and improves herbage quality through N-fixation, but this process is also interactively linked to the dynamics of other nutrients.Item The potential of Acacia Karroo leaf meal as a protein supplement for fattening goats(2013) Masiku, Elvin M.Acacia karroo is one of the most widespread and abundant indigenous tree legume species in Southern Africa. The tree possesses positive attributes such as high growth rates, drought tolerance, adaptation to acidic infertile soils and resistance to large temperature variations. In the recent past, A. karroo was deemed to be a severe encroacher, which adversely affected land utilisation and rangeland productivity. Research attention has been diverted from its riddance as a weed to its utilisation as an animal feed. Widespread adoption of feeding strategies based on A. karroo was mainly impeded by the presence of thorns and tannins. The objective of the study was to determine the effects of A. karroo leaf meal as a supplement on the growth performance feed intake, feed conversion ratio and body condition score of boar goats. Sixteen 3-month-old Boer goats were kept at the University of Namibia, Neudamm Campus farm. At the beginning of the experiment the goats had a mean body weight of 18.52 kg ± 0. 743 kg (mean ± S.E.) and a mean body condition score of (BCS) of 3.31 ± 0.176 (mean ± S.E.). From birth until weaning the kids were kept on natural pastures with their mothers. The goats were housed in an open sided barn for a period of 60 days, and were fed 600 g/head/day of pellets and Lucerne covering their maintenance and growth needs. For the purpose of the experiment, the goats were randomly divided into four treatment groups of four goats each. The goats were fed on A. karroo leaf meal at different levels 0%, 10%, 20% and 25% respectively. The effect of A. karroo supplement on growth performance (ADG), voluntary feed intake (VFI), feed conversion ratio (FCR) and body condition score on Boer goats was determined. There was a significant effect (P<0.05) of the A. karroo supplement ii on the VFI (average= 1.026kg ± 0.1954kg (mean ± S.E.)) and FCR (average FCR= 7.892). There was a significant effect (P<0.05) of A. karroo supplement on the ADG (average ADG =0.130kg ± 0.078kg (mean ± S.E.)) and BSC (average BCS = 4.94 ± 0.213 (mean ± S.E.)). The research demonstrated that Acacia karoo leaf meal can substitute protein sources in goat fattening meal up to an inclusion rate of 25%.