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ItemComparative analysis of malaria parasitaemia, reticulocytes, serum ferritin and malaria severity in sickle cell and non- sickle cell patients at Mbale Hospital, Eastern Uganda(Makerere University, 2025)Malaria and sickle cell disease (SCD) remain major public health challenges in sub-Saharan Africa, with Uganda bearing a high burden. Plasmodium falciparum, the most virulent malaria parasite species, causes severe illness, especially in individuals with homozygous SCD. While heterozygous SCD offers some malaria protection, the homozygous form complicates disease progression. Serum ferritin, an iron-storage protein and acute phase reactant, is difficult to interpret during co-infections. This study aimed at assessing P. falciparum parasitemia, serum ferritin levels and malaria severity in patients with and without SCD in Eastern Uganda. A total of 100 P. falciparum-positive participants; 50 SCD and 50 NSCD controls, both male and female with mean age of 12.3 and 14.4 years respectively, mean weight 34kgs across all the participants was considered. Malaria parasitemia were lower in SCD patients under 5yrs of age mean parasite count 691 (IQR: 583- 2239) compared to the counterparts 1,287(IQR: 646-10,143) p value 0.125. While in patients slightly aged over 5years SCD had median count 153(IQR: 99-199) and NSCD 345(IQR: 214 -431), p value 0.001. Reticulocyte counts were higher in both patient category under and above 5yers of age; SCD patients had median count of 15.7(IQR: 2.003-21.05) and NSCD 2(IQR: 1.65-3.27) p value 0.0253, 14.8(IQR: 9.6 - 25.5); 1, 99(1, 62-3.1), p value <0.0001 respectively. correlation analysis revealed a weak negative relationship between P.faliciparum parasitemia and reticulocyte count in SCD, and a weak positive in NSCD, Pearson coefficient (r) -0.183 and 0.138, p value 0.21 and 0.34 respectively at 95% CI. SCD patients under 5years had low median Serum ferritin levels (605 IQR: 256-1,307) compared to NSCD patients (682 IQR: 315-2336) p value 0.382, while among cases over 5 years, SCD had high median ferritin levels (2,211 IQR: 556.7-8,540) compared to NSCD (646.2 IQR: 246.3-3223) p value 0.342. Correlation analysis between serum ferritin levels and Plasmodium falciparum parasite counts for both patient groups revealed no statistical significant relationship, negative correlation (r = –0.057; p = 0.618) for SCD and positive correlation (r = 0.115; p = 0.427) for NSCD. Assessment for malaria severity, There was no malaria severity following insignificant statistical difference of heamatological parameters (heamoglobin, WBCs, Platelets) coupled with Clinical manifestations (Aneamia, heamaturia and cerebral malaria) in SCD patients to warrant severity of malaria. Keywords: Malaria parasitaemia, Reticulocytes, Serum ferritin, Sickle cell
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ItemDiversity and distribution of bees in selected districts of Central Uganda(Makerere University, 2025)Bees play a vital role in maintaining ecosystem functioning and agricultural productivity through pollination. However, their diversity and distribution are increasingly threatened by habitat degradation, land use changes, and unsustainable agricultural practices. This study investigated the diversity and distribution of bees in selected districts of Central Uganda, analysed the key environmental factors influencing their occurrence, and evaluated the effectiveness of different sampling methods for studying bee diversity. Data were collected from farmland, woodland, and grassland habitats using two sampling techniques, including pan traps and sweep nets, across both wet and dry seasons. Vegetation characteristics, including tree, shrub, herb, and grass cover, were also assessed to determine their influence on bee diversity and composition. Identification for some specimens was carried out to the genus and for others to species level. Diversity indices, ordination analyses, and complementarity assessments were applied to quantify community structure and sampling efficiency. A total of 112 species representing 47 genera and four bee families (Apidae, Colletidae, Halictidae, and Megachilidae) were recorded. Farmland supported the highest bee richness and abundance, likely due to habitat heterogeneity and floral diversity, while woodland and grassland harboured rare and habitat-specific species. Redundancy analysis revealed that herb and grass cover were more strongly associated with bee diversity than tree and shrub cover, suggesting dominance of generalist species that tolerate varying vegetation structures. Seasonal variation influenced genus composition. sweep nets captured a higher number of species and individuals than pan traps. Still, both methods exhibited partial overlap, indicating that combining them yields a more comprehensive assessment of bee communities. In conclusion, bee diversity in Central Uganda is shaped by habitat heterogeneity and vegetation cover, with herbaceous and grass cover providing essential foraging and nesting resources. The findings underscore the need to conserve a diversity of habitats, especially farmlands integrated with natural vegetation to support and sustain bee populations. It is recommended that future research adopt long-term, multi-seasonal monitoring using complementary sampling methods to improve species detection accuracy. Furthermore, local communities should be sensitised on sustainable land use practices that enhance floral diversity to promote bee conservation and pollination services.
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ItemOccurrence and distribution of Herpetofauna in Mutumba Wetland, Namayingo District, Uganda(Makerere University, 2025)The study investigated the diversity and distribution of herpetofauna in Mutumba wetland, Namayingo district. The overall objective of this study was to contribute herpetofaunal information that can be used to inform conservation planning and management. Data was collected for 12 days each month for a period of six months (November 2023 to March 2024). Visual encounter surveys, call count and opportunistic encounter techniques were used to accomplish the study objectives. Field surveys were performed around 40 random survey points separated by a distance of 500 meters within Mutumba wetland. Each of these survey points was surveyed 12 times to record the amphibian and reptile species. Six survey points were searched daily (day and night) for three hours per search by a team of three persons; sampling 3 points at night from 18:00 to 21:00 while another 3 points in the early morning hours from 06:00 am to 08:00 am. Data collected were analyzed using a variety of statistical methods namely: species accumulation curve, Simpson index of diversity, agglomerative cluster analysis and canonical correspondence analysis. The study documented 41 amphibian species from six families and 31 reptile species from twelve families in the Mutumba wetland. Amphibians were found across nine different microhabitats, while reptiles occupied ten. Both groups exhibited significant species diversity in cultivated land microhabitats, with Simpson’s index (D) values of 0.87 for amphibians and 0.88 for reptiles. However, amphibians exhibited greater species evenness compared to reptiles. The most abundant amphibian families were Ptychadenidae and Bufonidae with species Mascarene Grass Frog, Striped Grass Frog and African Common Toad being the most prevalent; while Scincidae dominated among reptiles. Amphibians were commoner in rice gardens and papyrus microhabitats, while reptiles were more common in tree canopy and artificial structures. Overlap in microhabitat use was observed, but environmental variables did not fully account for species distributions, suggesting other factors may be important. Species of the Hyperoliidae family, typically found in papyrus microhabitats, have become less common, possibly due to changes in the availability of these habitats from human activities. This study emphasizes the need for conservation of these habitats to ensure the sustainability of amphibian and reptile populations Future research should explore multiple environmental influences to enhance understanding of species distribution dynamics. Keywords: Amphibians, Reptiles, Diversity, Distribution, Mutumba
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ItemThe antibacterial activity of bitterleaf (gymnanthemum amygdalinum (delile) sch.bip.) And water hyacinth (pontederia crassipes, mart) and their effect on growth and survival of juvenile Nile tilapia (oreochromis niloticus, linnaeus 1758)(Makerere University, 2025)Aquaculture, particularly the cultivation of Nile tilapia Oreochromis niloticus, plays a crucial role in global food security. However, disease outbreaks and suboptimal growth rates present significant challenges. Natural plant-based additives offer promising alternatives to synthetic antibiotics and growth promoters. The study aimed to investigate the antibacterial activity of bitter leaf, Gymnanthemum amygdalinum (Syn: Vernonia amygdalina) and water hyacinth Pontederia crassipes Mart and the effects on the growth and survival of juvenile Nile tilapia. Dry powdered leaves of G. amygdalinum and P. crassipes were used for proximate and phytochemical analyses. Fish of average weight 1.4 ± 0.3g distributed into 9 rectangular glass tanks (3 treatments) were fed for 10 weeks to assess the influence of the treated diets on the fish performance. Further, 60 fish fed on plant-treated diet for 10 weeks and 60 new but healthy Oreochromis niloticus were injected intraperitoneally with an estimated 108 cells of Aeromonas hydrophila to evaluate the prophylactic and therapeutic potential of the ground leaves of G. amygdalinum and P. crassipes. Results revealed that G. amygdalinum contained significantly higher crude protein (25.47 ± 0.33%) and carbohydrate content (43.13 ± 0.14%) than P. crassipes, which had higher fibre (26.00 ± 0.05%) and lipid content (7.50 ± 0.10%). Additionally, G. amygdalinum contained four phytochemicals including flavonoids, alkaloids, saponins, and tannins, whereas P. crassipes contained flavonoids and tannins. Growth performance trials demonstrated that Nile tilapia fed on a diet supplemented with G. amygdalinum had a higher survival rate, grew faster, and gained more body mass compared to those fed on P. crassipes and the control group. However, the diets did not yield better condition factor, linked to possible adverse effects on the fish's health. In a challenge experiment with Aeromonas hydrophila, Nile tilapia fed on G. amygdalinum as prophylaxis showed a more enhanced survival rate of 85% than the P. crassipes and the control diet. However, there was a lower survival rate of 40% in fish fed on the two plants used as chemotherapy. The findings suggest that G. amygdalinum could be a valuable ingredient in fish feed formulation due to its high protein content and antibacterial properties, contributing to better growth performance and disease resistance in juvenile Nile tilapia. Further studies are recommended to optimize the inclusion levels of G. amygdalinum in fish diets, explore alternative extraction methods for bioactive compounds, and assess the long-term health impacts on Nile tilapia.
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ItemCharacterisation of petrochemical degrading bacteria from oil contaminated soils in automechanic workshops in Arua city, Uganda(Makerere University, 2025)Unregulated, indiscriminate disposal and poor handling of used oil products from automotive mechanic workshops in Uganda contaminate vast areas of soil and groundwater. The use of bacteria to clean up contaminated sites is considered to be a desirable bioremediation strategy. Soils from automobile workshops that have had continuous exposure to oil spills provide a suitable environment for isolating adapted bacteria for bioremediation. This study aimed to isolate, characterize, and identify petroleum hydrocarbon-degrading bacteria in oil-contaminated soils collected from auto mechanic workshops in Arua City, Uganda. The isolation and identification of cultured bacteria were performed using standard microbiological methods, including morphology and biochemical tests. The effectiveness of the bacteria in degrading petroleum hydrocarbons was evaluated following the dichlorophenol-indophenol redox indicator method during the 5-day treatment, using diesel as the sole carbon source. Molecular identification of the isolated petroleum hydrocarbon-degrading bacteria was conducted by PCR amplification and sequencing of the 16S rRNA gene. MEGA 11 software was used to draw a phylogenetic tree showing the relationships between the bacterial isolates. Results showed that the fifteen morphologically and biochemically distinct bacterial colonies mostly had gram-negative-rod-shaped catalase-positive bacteria, capable of utilising diesel as their sole carbon source at varying degrees. Isolates, particularly from genera such as Acinetobacter and Bacillus, known for hydrocarbon degradation, exhibited higher petrochemical degradation potential up to 90%. Molecular characterization identified all the isolates as Shewanella xiamenensis, Jeotgalibacillus marinus, Bacillus thuringiensis, Pseudomonas putida, Peribacillus simplex, Stutzerimonas chloritidismutans, Pseudomonas fluorescens, Acinetobacter johnsonii, Psychrobacillus insolitus, Acinetobacter pittii, Raoultella ornithinolytica, Acinetobacter calcoaceticus, Rhodococcus erythropolis, Enterococcus gallinarum, and Comamonas jiangduensis. These findings therefore provide valuable insights into the potential application of these microbial isolates in the bioremediation of diesel-contaminated environments.