Uganda Journal of Agricultural Science (UJAS)
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Basic density, modulus of elasticity and modulus of rapture of Artocarpus heterophyllus
Get PDFArtocarpus heterophyllus is increasingly being utilised in the furniture industry despite the limited information regarding its properties. This study was conducted to categorise A. heterophyllus based on its basic density, Modulus of Elasticity and Modulus of Rapture. Specimens were prepared from three mature trees (≥15 years of age) obtained from a farmland in Nyabyeya parish, Budongo Sub-county, Masindi district. From each tree three bolts of height 800 mm were cut at Diameter at Breast Height (1.3 m), 45% tree height and 75% of tree height. The bolts were sawn into scantlings using through and through method. Specimens for static bending and basic density tests were prepared according to Lavers (1983). Bending tests were done in accordance with BS 373 (1957) using a Testometric AX Universal Testing Machine. Basic density was determined by the water displacement method. The mean MOE was 6,378 Nmm-2, the mean MOR was 119 Nmm-2 and mean basic density was 458 Kgm-3. Based on these properties, A. heterophyllus qualifies as light construction timber. However, further research on other strength properties of A. heterophyllus is recommended for effective utilisation of its wood for structural purposes
On-farm post-harvest physical grain losses of “Kaiso” rice variety in Eastern Uganda
Get PDFRice, Oryza sativa is one of the major crops through which people in eastern Uganda particularly Butaleja district earn their livelihoods. Kaiso is the main swamp rice variety grown and marketed in the region. The smallholder farmers who are the majority use rudimentary technologies to undertake post-harvest operations. Technocrats and policy makers have observed and noted with concern that high physical grain losses are occurring along the various post-harvest operations. The purpose of this study was, therefore, to generate post-harvest physical grain losses of rice during harvesting, threshing, drying and cleaning at farms of smallholder farmers in Doho rice irrigation scheme. Methodology involved experiments using quadrants and social interviews based on participatory research techniques. A total of 48 farmers and 5 extensions officers were involved in the various parts of the study. The results showed that highest grain losses occur during harvesting and threshing and the average quantities were 6.7% (285.1 kg ha-1 of paddy) and 4.7% (183 kg ha-1 of paddy). The total average physical grain loss during harvesting, threshing, drying and cleaning was 13.5% (578.8 kg ha-1 of paddy). The results generated correlate well with similar findings in the Asian countries reported by Food and Agricultural Organisation (FAO) of the United Nations
The past, present and projected scenarios in the Lake Albert and Albert Nile fisheries: Implications for sustainable management
Get PDFLake Albert is one of the largest lakes in Uganda that still supports a multi-species fishery which as a result of variable adult sizes of the species, causes management challenges especially in relation to gear mesh size enforcement. Prior to the 1980s, commercial species were 17 large- sized fishes especially Githarinus, Citharinus, Distichodus, niloticus and Lates spp that were confined to inshore habitats of the lake and were thus rapidly over fished. Frame and catch assessment surveys conducted in this study revealed a >80% dominance of small size fish species (Neobola_bredoi and Brycinus nurse) and a 40 – 60% decrease in the contribution of the large commercial species. Sustainability of small size fish species is uncertain due to seasonal fluctuations and low beach value. At about 150,000 tons of fish recorded from Lake Albert and Albert Nile, the beach value was estimated at 55.3 million USD. Despite the noted decline in catches of the large sized fishes their contribution was more than 50% of total beach value. Therefore, management measures should couple value addition for the small sized species and maintain effort regulation targeting recovery of the large previously commercial specie
Knowledge and perceptions of smallholder dairy farmers of cattle disease burdens in selected agro-ecological zones of Uganda
Get PDFDiseases have continued to affect production and productivity in smallholder dairy farming systems in Uganda. This study sought to establish farmers’ knowledge and perceptions of disease burden in the Eastern Semi-Arid Zone (ESAZ), Lake Victoria Basin (LVB) and Western Rangelands (WR) agro-ecological zones (AEZs). A structured questionnaire was administered to 150 farm household heads or cattle attendants. Data analysis by cross tabulations was done using SPSS Statistical Software and descriptive statistics generated in XLSTAT. Linear Discriminant analysis and Multivariate Analysis of Variance were computed to establish significant relationships (P<0.05) between variables. East Coast fever (ECF), calf scours, foot rot, mastitis and fascioliasis were reported of high prevalence (≥50%), while brucellosis and eye infection had low prevalence (≤16.7%). Season, age and breed of cattle were significantly associated with severity, morbidity, mortality and treatment costs in all AEZs. Morbidity and mortality were higher during the long (4.5; 0.7) than short rains (3.1; 0.6), respectively. Comparatively, average treatment costs were higher during the short rains (US 17) each rains lasting three months. Results of our study show that some diseases were common to all AEZs, yet ESAZ had a higher disease burden than WR and LVB
Combined effect of grain solarisation and oiling on the development of Sitophilus zeamais Motsch
Get PDFThe maize weevil (Sitophilus zeamais Motsch. Coleoptera; Curculionidae) is one the most important storage pests of maize in East Africa. We investigated the combined efficacy of grain oiling with vegetable oil and 2- hour grain solarisation on S. zeamais damage to maize. Maize, Longe 1 variety was treated at dosages of 0, 1, 2, 4 ml per kg of grain, and artificially inoculated with 12- adult S. zeamais weevils. Combination of grain oiling and solarisation of grain at 1, 2 and 4 ml per kg significantly reduced weevil emergence (F=3.06, P< 0.001) compared to the singular treatments. Solarised grain had 5.5 ± 0.3% damage compared to less than 1% damage where grain was both solarised and oiled at 1, 2 and 4 ml per kg dosage levels. Oiled and unsolarised maize grain treatments significantly (F= 18.27, P< 0.001) had better percentage viability at 93.0 ± 0.7; 91.5 ± 0.9, 91.3 ± 0.9 at 1,2, 4 ml per kg respectively, compared to 76.5 ± 3.7 for the untreated maize grain. Combined oiling and solarisation provides residual grain protection to maize against S. zeamais on maize without compromising quality and provides an alternative management option for the pest
Physical quality and safety assessment of selected varieties of local paddy and milled rice processed by cottage rice mills in Uganda
Get PDFThe urban and peri-urban population provide niche markets for rice in Uganda. The local rice industry, dominated by smallholder farmers and cottage mills has failed to meet quality requirements of quality-sensitive consumers. Due to lack of information on physical quality and safety of the locally grown and processed rice, informed decision making on investments in the sector has been compromised. Using standard analytical and physical methods, local paddy and milled rice main varieties (NERICA 4, Kaiso and Supa) sampled from all major rice growing districts of Uganda were assessed for quality and safety. The results showed that paddy supplied to rice millers exhibited low quality characteristics exemplified by fissure levels of 60%, foreign matter of 6.1%, moisture content of 10.6% and aflatoxin contamination of 18 pbb. Similarly, milled rice obtained from different parts of the country and processed by cottage mills exhibited low market value namely; aflatoxin up to 19.5 ppb, 64.3% broken grain, 0.8% foreign matter and 0.06% rancidity. Although rice available on the market was fairly safe for consumption, the physical quality which determines the price tag required urgent improvement. Hence the need for measures to improve post-harvest handling and processing technologies for smallholder farmers and cottage mills
Progression of Cassava Brown Streak Disease (CBSD) in infected cassava roots in Uganda
Get PDFCassava Brown Streak disease (CBSD) has and continues to be a major threat to the cassava industry in Uganda. The most economically damaging symptom of CBSD occurs on the roots as a yellow/brown, corky necrosis. However, the onset and development of this necrosis is not known. Therefore, this study was conducted to understand the progression of CBSD root necrosis.The experiment was conducted at Namulonge (central Uganda), where the CBSD pressure and whitefly population is high. Four CBSD susceptible genotypes (TME204, TMSI92/0067, MH97/2961, and Bamunanika) and five CBSD tolerant genotypes (TME14, NASE 3, NASE 1, MM96/0686 and 28 TME 14) were used. The experiment was laid out in a split-plot factorial experiment with three replicates. CBSD root necrosis was assessed at 4 months after planting (MAP) and, thereafter, at monthly intervals until 12 MAP. Results indicated significant differences (P<0.001)among reaction grades (susceptible and tolerant), genotypes and sampling times. CBSD root necrosis commences as early as 4 MAP in susceptible genotypes with a severity of 2 and incidence of 16.67%. These findings have important implications for CBSD breeding particularly when evaluating seedlings and/or clonal plants that often have different number of roots
Influence of diets containing raw or heat processed cowpea on the performance and gut health of broiler chickens
Get PDFAn experiment was conducted to determine the influence of diets containing raw or heat processed cowpeas on the performance and gut health of broiler chickens. Forty eight day-old male broiler chicks were used in this study. The birds were randomly assigned to six mobile battery cages with eight birds per cage. The cages were assigned to three isonitrogenous and isocaloric diets in duplicate so that each treatment group had sixteen birds. The birds were fed for nine days on the following diets: T1 (control diet - corn-soy); T2 (20% of raw cowpea) and T3 (20% of roasted cowpea). The results showed no effect of either cowpea treatment versus control diet on weight gain, feed gain or cumulative period performance at day 5. However, by day 9, significantly higher weight gain was observed in chicks fed raw cowpeas compared to either roasted cowpeas or the control diet (P<0.05). Feed conversion and cumulative performance indices did not differ between groups fed the control diet or raw cowpeas, but chicks fed roasted cowpeas performed significantly poorer by day 9 (P<0.05). Although the raw cowpeas supported optimal growth in the chicks, histopathology indicated that the raw cowpeas were associated with inflammation of the duodenum. Gut morphology indicated that on day 5 duodenal crypt depth was significantly greater in birds fed on roasted cowpeas compared with the other two treatments. The differences between treatments in villus length, width, crypt depth, or muscle appearance were not apparent by day 9. Gastrointestinal viscosity was higher in the group fed T3 compared with T1 and T2. Although these results are contrary to expectations, there was no indication of over processing/ overcooking of the cowpeas that may have decreased protein quality. Data suggest that 20% of raw Mozambican cowpeas can be incorporated into broiler starter diets with no negative effects on growth or feed conversion
Ecology and Conservation of Acacia senegal in the Rangelands ofLuwero and Nakasongola Districts
Get PDFEcology and conservation status of Acacia senegal in the rangelands of Luwero and Nakasongola Districts were assessed between November 2002 and February 2003. Sixty plots measuring 50 x 50 m were laid at 50 m intervals along six 1,000 m transects, and the Diameter at Breast Height (DBH), of Acacia senegal trees measured. Each tree was visually assessed for physical damages as health indicators. Maturity class, terrain types and other trees growing together with Acacia senegal were identified and recorded. A structured questionnaire and interviews were used to collect data on the constraints and opportunities of conserving and managing Acacia Senegal. Data on the population structure, maturity class and stock density of Acacia senegal were analysed using MINITAB and DECORANA. The population structure of Acacia senegal trees was unbalanced, with only 24% young trees (DBH < 8 cm). Sixty five percent of trees were old (DBH > 8 cm) and 84% physically damaged. Hills had significantly (P < 0.05) higher tree density than plains and streams. Thirty-two tree species were recorded growing together with Acacia senegal in the rangelands and the most common were Acacia mellifera, Acacia hockii, Acacia seyal, Combretum collinum and Combretum molle. Grazing livestock, bush fires, land tenure, tree tenure, pests and diseases were the major challenges to conservation of Acacia senegal in the rangelands. Collaborative conservation and management plan should be developed to conserve the species. Impacts of livestock grazing, settlement and farming on regeneration of Acacia senegal should be assessed before developing strategies for management and conservation
Agroforestry potential of Acacia senegal in the rangelands of luwero and Nakasongola districts
Get PDFAgroforestry potential of Acacia senegal in the rangelands of Luwero and Nakasongola districts was assessed between November 2002 and February 2003. Proportion of farmland under A. senegal was assessed by farm transect walks. A structured questionnaire and interviews were administered to collect information on the socio-economic profile of the farmers and constraints and opportunities to management of A.senegal. Questionnaire responses were entered in SPSS and logistic regression used to show the effects ofsocio-economic variables on people's willingness to plant and manage A . senegal trees on their farm . The proportion of farm land under A . senegal and other tree species is 16.78%. Acacia senegal is a source of firewood, fodder, fencing post, soil fertility improvement, medicine and gum. Education, farm size, gender, occupation and ownership of domestic animals significantly influenced the local people's willingness to plant and manage A. senegal trees. Therefore, local people need to be mobilised and educated on the agroforestry potentialand conservation value of Acacia senegal