NRU :: Browsing by Author "Muwanika, Vincent B."

Browsing by Author "Muwanika, Vincent B."

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Characterisation of recent foot-and-mouth disease viruses from African buffalo (Syncerus caffer) and cattle in Kenya is consistent with independent virus populations
(BMC veterinary research, 2015) Wekesa, Sabenzia N.; Sangula, Abraham K.; Belsham, Graham J.; Tjørnehøj, Kirsten; Muwanika, Vincent B.; Gakuya, Francis; Mijele, Dominic; Siegismund, Hans R.
Understanding the epidemiology of foot-and-mouth disease (FMD), including roles played by different hosts, is essential for improving disease control. The African buffalo (Syncerus caffer) is a reservoir for the SAT serotypes of FMD virus (FMDV). Large buffalo populations commonly intermingle with livestock in Kenya, yet earlier studies have focused on FMD in the domestic livestock, hence the contribution of buffalo to disease in livestock is largely unknown. This study analysed 47 epithelia collected from FMD outbreaks in Kenyan cattle between 2008 and 2012, and 102 probang and serum samples collected from buffalo in three different Kenyan ecosystems; Maasai-Mara (MME) (n = 40), Tsavo (TSE) (n = 33), and Meru (ME) (n = 29). Results: Antibodies against FMDV non-structural proteins were found in 65 of 102 (64%) sera from buffalo with 44/102 and 53/102 also having neutralising antibodies directed against FMDV SAT 1 and SAT 2, respectively. FMDV RNA was detected in 42% of the buffalo probang samples by RT-qPCR (Cycle Threshold (Ct) ≤32). Two buffalo probang samples were positive by VI and were identified as FMDV SAT 1 and SAT 2 by Ag-ELISA, while the latter assay detected serotypes O (1), A (20), SAT 1 (7) and SAT 2 (19) in the 47 cattle epithelia. VP1 coding sequences were generated for two buffalo and 21 cattle samples. Phylogenetic analyses revealed SAT 1 and SAT 2 virus lineages within buffalo that were distinct from those detected in cattle. Conclusions: We found that FMDV serotypes O, A, SAT 1 and SAT 2 were circulating among cattle in Kenya and cause disease, but only SAT 1 and SAT 2 viruses were successfully isolated from clinically normal buffalo. The buffalo isolates were genetically distinct from isolates obtained from cattle. Control efforts should focus primarily on reducing FMDV circulation among livestock and limiting interaction with buffalo. Comprehensive studies incorporating additional buffalo viruses are recommended.
Characterization of Foot-And-Mouth Disease Viruses (FMDVs) from Ugandan Cattle Outbreaks during 2012-2013: Evidence for Circulation of Multiple Serotypes
(PLoS One, 2015) Namatovu, Alice; Tjørnehøj, Kirsten; Belsham, Graham J.; Dhikusooka, Moses T.; Wekesa, Sabenzia N.; Muwanika, Vincent B.; Siegismund, Hans R.; Ayebazibwe, Chrisostom
To investigate the foot-and-mouth disease virus (FMDV) serotypes circulating in Uganda’s cattle population, both serological and virological analyses of samples from outbreaks that occurred during 2012–2013 were performed. Altogether, 79 sera and 60 oropharyngeal fluid (OP)/ tissue/oral swab samples were collected from herds with reported FMD outbreaks in seven different Ugandan districts. Overall, 61/79 (77%) of the cattle sera were positive for antibodies against FMDV by PrioCHECK FMDV NS ELISA and solid phase blocking ELISA detected titres 80 for serotypes O, SAT 1, SAT 2 and SAT 3 in 41, 45, 30 and 45 of these 61 seropositive samples, respectively. Virus neutralisation tests detected the highest levels of neutralising antibodies (titres 45) against serotype O in the herds from Kween and Rakai districts, against SAT 1 in the herd from Nwoya district and against SAT 2 in the herds fromKiruhura, Isingiro and Ntungamo districts. The isolation of a SAT 2 FMDV from Isingiro was consistent with the detection of high levels of neutralising antibodies against SAT 2; sequencing (for the VP1 coding region) indicated that this virus belonged to lineage I within this serotype, like the currently used vaccine strain. From theWakiso district 11 tissue/swab samples were collected; serotype A FMDV, genotype Africa (G-I), was isolated from the epithelial samples. This study shows that within a period of less than one year, FMD outbreaks in Uganda were caused by four different serotypes namely O, A, SAT 1 and SAT 2. Therefore, to enhance the control of FMD in Uganda, there is need for efficient and timely determination of outbreak virus strains/serotypes and vaccine matching. The value of incorporating serotype A antigen into the imported vaccines along with the current serotype O, SAT 1 and SAT 2 strains should be considered.
Colonization of woody seedlings in the understory of actively and passively restored tropical moist forests Running head: Seedling colonization in afrotropical forests
(Restoration Ecology, 2019) Ssekuubwa, Enock; Muwanika, Vincent B.; Esaete, Josephine; Tabuti, John R. S.; Tweheyo, Mnason
The status of woody seedling colonization gives clues about the self-sustainability of restored forests, a tenet of restoration success. Little is known about woody seedling colonization in restored afrotropical forests. We evaluated effects of restoration methods (active vs. passive), sampling year, restoration age and distance from old-growth forests on seedling colonization in restored afrotropical moist forests. Seedlings were measured in 2011 and 2014 in 71 clusters of 284 permanent sampling plots (12.6 m2 each) in actively (initially 3–16 years old) and 21 clusters of 63 plots in passively restored forests (initially 16 years old) in Kibale National Park, western Uganda. Seedlings were also measured in nearby old-growth forests in 3 clusters of 5 plots in 2014. We determined species diversity, richness and abundance per plot, and species composition as measures of seedling colonization in restored and old-growth forests. We found that diversity, richness, and abundance of seedlings were significantly higher in passively than actively restored forests. Diversity and richness, but not abundance significantly increased between sampling years and with restoration age. Distance from old-growth forests did not significantly affect diversity, richness and abundance. Species composition of actively and passively restored forests was different from that of old-growth forests after 19 years since restoration started. Our results show that passive restoration should be the preferred method for recovering afrotropical forests, and highlight the effect of continued management on biodiversity of restored forests.
Combining Landscape Genomics and Ecological Modelling to Investigate Local Adaptation of Indigenous Ugandan Cattle to East Coast Fever
(Frontiers in Genetics, 2018) Vajana, Elia; Barbato, Mario; Colli, Licia; Milanesi, Marco; Rochat, Estelle; Fabrizi, Enrico; Mukasa, Christopher; Del Corvo, Marcello; Masembe, Charles; Muwanika, Vincent B.; Kabi, Fredrick; Stewart Sonstegard, Tad; Huson, Heather Jay; Negrini, Riccardo; Consortium, NextGen; Joost, Stéphane; Ajmone-Marsan, Paolo
East Coast fever (ECF) is a fatal sickness affecting cattle populations of eastern, central, and southern Africa. The disease is transmitted by the tick Rhipicephalus appendiculatus, and caused by the protozoan Theileria parva parva, which invades host lymphocytes and promotes their clonal expansion. Importantly, indigenous cattle show tolerance to infection in ECF-endemically stable areas. Here, the putative genetic bases underlying ECF-tolerance were investigated using molecular data and epidemiological information from 823 indigenous cattle from Uganda. Vector distribution and host infection risk were estimated over the study area and subsequently tested as triggers of local adaptation by means of landscape genomics analysis. We identified 41 and seven candidate adaptive loci for tick resistance and infection tolerance, respectively. Among the genes associated with the candidate adaptive loci are PRKG1 and SLA2. PRKG1 was already described as associated with tick resistance in indigenous South African cattle, due to its role into inflammatory response. SLA2 is part of the regulatory pathways involved into lymphocytes’ proliferation. Additionally, local ancestry analysis suggested the zebuine origin of the genomic region candidate for tick resistance.
Conservation of priority woody species on farmlands: A case study from Nawaikoke sub-county, Uganda
(Applied Geography, 2011) Tabuti, John R.S.; Muwanika, Vincent B.; Arinaitwe, Mary Z.; Ticktin, Tamara
In tropical Africa, woody species provide products and services that millions of people depend on. However, many of these species are also threatened and declining and this can have serious livelihood consequences for communities who depend on them. Identifying which species are most at risk and which ones are being conserved is therefore critical. In this study, we undertook a survey in Nawaikoke Sub-county, Uganda to assess which of 26 most preferred species are managed on farmland, to identify what environmental factors influence their availability, and to describe their conservation statuses. Individuals of these species were enumerated and measured in 320 plots across the eight parishes of Nawaikoke. Seven of the 26 species were not encountered in any plots. The rest were found close to homesteads in homegardens, in crop gardens and in young fallows on well drained soils. Only Combretum collinum and Acacia seyal were associated with old fallows and poorly drained clay loamy soils. Mangifera indica, Milicia excelsa, Ficus natalensis, Ficus sycomorus, Artocarpus heterophyllus and Albizia coriaria were found in numerous plots in at least six of the eight parishes, and at relatively high densities and we consider them to be at the lowest risk of disappearance from the landscape. Size-class distributions of all preferred species, regardless of their abundance, exhibited little recruitment from juvenile life stages. We conclude that most of the species face some level of threat through destruction of seedlings and saplings and that for these species to persist into the future there is need to work with farmers to encourage them to plant or spare those found growing naturally. There is a high potential for these species to increase in abundance because they grow in a wide diversity of farm niches. For the farmers to become more involved, focus should primarily be on native species that provide shade, fruits and timber. Some of these target species also play ecological roles, increasing their functionality. Lastly, there is need to protect non-crop habitats like fallows and wetlands.
Conversion of native vegetation in protected areas fuels co2-equivalent losses in Uganda
(Nova Publishers, 2017) Olupot, Giregon; Otukei, John R.; Muwanika, Vincent B.; Esaete, Josephine; Tabuti, John R.S.
Protected areas (PAs) play many unique yet, irreplaceable ecosystem functions, most importantly, mitigation of CO2 emissions. However, the influence of land use and land cover (LULC) change on the sequestration of carbon in these PAs and related ecosystems is strikingly limited. This chapter consolidates the scanty data on the impact of LULC change on biomass and soil carbon stocks for evaluation of the impact of such LULC changes on CO2-equivalent (CO2-e) fluxes in the PAs of Uganda. The gist of the study was to test the hypothesis that any change in LULC or shift away from the pristine LULC type (PAs in our case), would lead to a net CO2-e loss. The results indicate that deliberate revegetation of an old (39–63 years) pine plantation segment of Kibale National Park with indigenous tree species resulted in a net 56.8% increase in CO2-e sequestration (18.10 Mg CO2-e ha-1) in 10 years. In Mt Elgon National Park (MENP) with mature native forest (>80 years), over 87% of the CO2-e was sequestered by mature trees in the intact tropical high forest (ITHF). A change in LC from an ITHF to a degraded tropical high forest (DTHF) to grassland has resulted in net losses of 91.5% and 93.6% of the CO2-e sequestered by the ITHF, respectively. In Bwindi Impenetrable National Park, a shift from closed forest canopy (CFC) to open forest canopy (OFC) translated into a net loss of over 76.8% of CO2-e. There was a significant effect of LULC change on the depth distribution of soil carbon stocks in KNP. Highest soil carbon stocks (19.0±0.86 Mg C ha-1) were observed under maize whereas the smallest (16.4±1.54 Mg C ha-1) were under ITHF. However, about 70% of the soil carbon stocks under the forest covers (11.2 Mg C ha-1) were accumulated deeper than 0–0.15 m compared with only about 47% (about 8.9 Mg C ha-1) under maize. The 2.3 Mg C ha-1 in the 0.15–0.6 m layer of soil under ITHF and restored forest in excess of what we observed under maize, highlights the importance of the forests in sequestering carbon in the area and potentially in related ecosystems elsewhere in Uganda. Our synthesis indicates that change in LULC or shift away from native LULC type leads to a net loss of CO2-e. Therefore, conservation of such PAs in Uganda is not an option but mandatory for climate change mitigation.
Determinants Of Participation In State And Private PES Projects In Uganda
(Scientific African, 2020) Aganyira, Kellen; Kabumbuli, Robert; Muwanika, Vincent B.; Tabuti, John R.S.; Sheil, Douglas
Climate change mitigation can improve rural livelihoods through payment for environmental services (PES) approaches. However, participation in PES projects is voluntary, uncertain and some people's participation is more important than others. In this article, we use quantitative and qualitative methods to examine factors that determine local peoples’ participation in state (Rwoho and Kasagala) and private (‘Undisclosed’ and Hoima) forestry carbon projects in Uganda. We find that such determinants vary within and between projects. For example, older people with more land parcels were more likely to participate in private projects compared to their counterparts in state projects. In plantation forests, participation was motivated by access to forest products (timber and charcoal), while the desire to conserve water sources was important for participants adjacent to natural forests. While expected carbon payments were important in one state project, they were less significant in the others. Non-participation was linked to high entry costs, distrust for forest managers in state projects and non-ownership of natural forests. In all case studies, non-participation was mainly associated to limited project information. To gain broad participation, Reducing Emissions from Deforestation and forest Degradation (REDD+) and other PES mechanisms must critically identify and consider community specific needs, expectations and concerns in their design and implementation. This requires willingness to diagnose community concerns and allow adjustments.
Diversity and transboundary mobility of serotype O foot-and-mouth disease virus in East Africa: Implications for vaccination policies
(Infection, Genetics and Evolution, 2010) Balinda, Sheila N.; Sangula, Abraham K.; Heller, Rasmus; Muwanika, Vincent B.; Belsham, Graham J.; Masembe, Charles; Siegismund, Hans R.
Foot-and-mouth disease (FMD) virus serotype O has been responsible for most reported outbreaks of the disease in East Africa. A sustained campaign for the past 40 years to control FMD mainly by vaccination, combined with quarantine and zoosanitary measures has been undertaken with limited success. We investigated the genetic relationships among serotype O strains in eastern Africa using complete VP1 coding region sequences obtained from 46 FMD virus isolates collected in Kenya in the years 1964–2008 and 8 Ugandan isolates collected between 1999 and 2006. In addition, 21 selected FMDV sequences from Genbank representing reference strains from eastern Africa and elsewhere were included in the Bayesian inference analyses and the detection of selection forces. The results confirmed previous observations that eastern Africa harbours four distinct topotypes (clades with >15% sequence divergence). All but one strain isolated post-2000 belonged to topotypes EA-2, EA-3 and EA-4, while all three vaccines have been based on strains in the EA-1 topotype. The estimated dN/dS ratios across the individual codons of the entire VP1 coding region revealed that purifying (negative) selection constituted the dominant evolutionary force. Cross-border disease transmission within the region has been suggested with probable incursions of topotypes EA-3 and EA-4 into Kenya and Uganda from neighboring Ethiopia and Sudan. Weconclude that the vaccines have probably been effective in controlling EA-1, but less so for the other topotypes and propose a more comprehensive representation of topotypes in the development of new vaccines in recognition of the considerable diversity and transboundary nature of serotype O.
Evolutionary analysis of foot-and-mouth disease virus serotype SAT 1 isolates from east Africa suggests two independent introductions from southern Africa
(BMC evolutionary biology,, 2010) Sangula, Abraham K.; Belsham, Graham J.; Muwanika, Vincent B.; Heller, Rasmus; Balinda, Sheila N.; Masembe, Charles; Siegismund, Hans R.
In East Africa, foot-and-mouth disease virus serotype SAT 1 is responsible for occasional severe outbreaks in livestock and is known to be maintained within the buffalo populations. Little is known about the evolutionary forces underlying its epidemiology in the region. To enhance our appreciation of the epidemiological status of serotype SAT 1 virus in the region, we inferred its evolutionary and phylogeographic history by means of genealogy-based coalescent methods using 53 VP1 coding sequences covering a sampling period from 1948-2007. Results: The VP1 coding sequence of 11 serotype SAT 1 FMD viruses from East Africa has been determined and compared with known sequences derived from other SAT 1 viruses from sub-Saharan Africa. Purifying (negative) selection and low substitution rates characterized the SAT 1 virus isolates in East Africa. Two virus groups with probable independent introductions from southern Africa were identified from a maximum clade credibility tree. One group was exclusive to Uganda while the other was present within Kenya and Tanzania. Conclusions: Our results provide a baseline characterization of the inter-regional spread of SAT 1 in sub-Saharan Africa and highlight the importance of a regional approach to trans-boundary animal disease control in order to monitor circulating strains and apply appropriate vaccines.
Evolutionary history of Nile perch Lates sp. inferred from mitochondrial DNA variation analyses
(Zoological Studies, 2013) Mwanja, Matthew T.; Muwanika, Vincent B.; Masembe, Charles; Nyakaana, Silvester; Waiswa Mwanja, Wilson
Evolutionary histories of aquatic species are often characterized by distinct patterns of genetic variation, which in part reflect drainage evolution. In the present study, the consequences of paleo-environmental changes on patterns of genetic variation of the mitochondrial DNA control region in Nile perch Lates sp. sampled from seven water bodies across the African continent were investigated. Results: In a total sample of 124 individual sequences, 37 distinct haplotypes were observed, and 78.4% of these haplotypes were location specific. Haplotypes were found to cluster into two major groups, one composed of individuals sampled from East Africa and another from West Africa, with no haplotypes shared in between. Conclusion: These lineages may have developed in geographical isolation during the Pleistocene and have remained largely allopatric without gene flow (Nm = 0.0) since that time. There was also evidence that both of these genetic lineages have undergone recent population expansions. We interpret these results in light of the recent evolution of Africa's modern drainage network.
Genetic consequences of population expansions and contractions in the common hippopotamus (Hippopotamus amphibius) since the Late Pleistocene
(Molecular Ecology, 2015) Stoffel, Céline; Dufresnes, Christophe; Okello, John Bosco A.; Noirard, Christian; Joly, Pierre; Nyakaana, Silvester; Muwanika, Vincent B.; Alcala, Nicolas; Vuilleumier, Séverine; Siegismund, Hans R.; Fumagalli, Luca
Over the past two decades, an increasing amount of phylogeographic work has substantially improved our understanding of African biogeography, in particular the role played by Pleistocene pluvial-drought cycles on terrestrial vertebrates. However, still little is known on the evolutionary history of semi-aquatic animals, which faced tremendous challenges imposed by unpredictable availability of water resources. In this study, we investigate the Late Pleistocene history of the common hippopotamus (Hippopotamus amphibius), using mitochondrial and nuclear DNA sequence variation and range-wide sampling. We documented a global demographic and spatial expansion approximately 0.1-0.3 My ago, most likely associated with an episode of massive drainage overflow. These events presumably enabled a historical continent-wide gene flow among hippopotamus populations, and hence no clear continental-scale genetic structuring remains. Nevertheless, present-day hippopotamus populations are genetically disconnected, probably as a result of the mid- Holocene aridification and contemporary anthropogenic pressures. This unique pattern contrasts with the biogeographic paradigms established for savannah-adapted ungulate mammals and should be further investigated in other water-associated taxa. Our study has important consequences for the conservation of the hippo, an emblematic but threatened species that requires specific protection to curtail its long-term decline.
Genetic evidence of successful establishment of the Nile perch (Lates spp. L.) in East African lakes and implications for management
(Management of Biological Invasions, 2012) Mwanja, Matthew T.; Waiswa Mwanja, Wilson; Muwanika, Vincent B.; Masembe, Charles; Nyakaana, Silvester
Nile perch establishment in novel ranges in East Africa is one of the most successful freshwater invasion stories in the recent history. It became ecologically dominant and well established in several lakes in the Lake Victoria Region in a period of less than 5 decades. Genetic diversity of both introduced and native populations were assessed and patterns compared in order to establish the genetic consequences of their introductions. Genetic variation was surveyed at both the mitochondrial control region (CR) and at nine microsatellite loci. A total of 527 Nile perch fish were sampled from 5 East African lakes: native source populations were examined from lakes Albert and Turkana while introduced populations were sampled from lakes Kyoga, Nabugabo and Victoria. Both types of markers revealed higher average genetic diversity for invasive species (HE = 0.70, h = 0.81) than for native source populations (HE = 0.66, h = 0.69). Both populations scored relatively higher than the average for freshwater fishes (HE = 0.62). Both native and introduced populations had 2 underlying genetic groupings in similar proportions as revealed by the STRUCTURE program. The high genetic diversity was most probably a consequence of higher numbers of propagules than outlined by official records of introductions. Use of high number of individuals at stocking is probably the reason for apparently minimized ‘founder effects’ of Nile perch in the introduced ranges. The two underling populations revealed through genetic analysis may be representatives of the two subspecies of Nile perch previously reported in other studies. Implications to the management of this fishery in the East African region is that with the relatively high genetic diversity, the species could be sustainably exploited if it were effectively managed. In addition, further studies of the life histories and other attributes of the two genetic groupings of Nile perch in the region are recommended, as they may require different management plans.
Genome Sequences of Five African Swine Fever Virus Genotype IX Isolates from Domestic Pigs in Uganda
(Microbiology Resource Announcements, 2018) Masembe, Charles; Sreenu, Vattipally B.; Filipe, Ana Da Silva; Wilkie, Gavin S.; Ogweng, Peter; Mayega, Francis J.; Muwanika, Vincent B.; Biek, Roman; Palmarini, Massimo; Davison, Andrew J.
Complete genome sequences of five African swine fever virus isolates were determined directly from clinical material obtained from domestic pigs in Uganda. Four sequences were essentially identical to each other, and all were closely related to the only known genome sequence of p72 genotype IX. African swine fever (ASF) is a contagious, highly lethal, hemorrhagic disease of domestic pigs caused by African swine fever virus (ASFV) (1). ASF results in up to 100% mortality. Its epidemiology is complex and adopts different patterns in Africa and Europe (2–6). The lack of effective interventions makes it extremely difficult to prevent or control and results in severe economic losses (7–11). ASFV is the sole member of the genus Asfivirus, family Asfarviridae, and has a linear, double-stranded DNA genome of 170 to 190 kbp (12, 13). There are currently 24 recognized genotypes (14, 15). Full genome sequences enable large strides toward developing control measures to use during epidemics. Available ASFV complete genome sequences number only 20, of which 3 are from eastern Africa (Kenya) but none are from Uganda, in which ASFV is also endemic. We present the first genome sequences of strains collected from domestic pigs in Uganda
Geographic distribution of non-clinical Theileria parva infection among indigenous cattle populations in contrasting agro-ecological zones of Uganda: implications for control strategies
(Parasites & vectors, 2014) Kabi, Fredrick; Masembe, Charles; Muwanika, Vincent B.; Kirunda, Halid; Negrini, Riccardo
Non-clinical Theileria parva infection among indigenous cattle occurs upon recovery from primary disease during the first year of life. Continuous exposure to infection through contaminated tick infestations with absence of clinical disease gives rise to endemic stability. Endemic stable populations may become sources of infection if contaminated tick vectors are shared with susceptible exotic cattle. This study aimed at establishing a nationwide distribution of non-clinical T. parva infection among indigenous cattle populations to inform novel control strategies. Methods: The occurrence of non-clinical T. parva infection among apparently healthy 925 indigenous cattle from 209 herds spread out in 10 agro-ecological zones (AEZs) was determined using a nested PCR assay. The influence of AEZ, breed, sex, age and farmers’ ranking of ECF importance were interrogated for influence of non-clinical parasite occurrence. Results: The overall prevalence of non-clinical T. parva infection was 30% (278/925). A gradual increase of non-clinical T. parva infection was observed ranging from 17% (95% CI: 0.03 – 0.23) to 43% (95% CI: 0.3 – 0.55) in the North Eastern Savannah Grasslands (NESG) to the Western Highland Ranges (WHR) respectively. A similarly associated 18% (95% CI: 0.07 – 0.28) and 35% (95% CI: 0.3 – 0.39) non-clinical parasite prevalence was observed among the East African shorthorn Zebu (EASZ) and Ankole cattle respectively. Average herd level non-clinical T. parva prevalence was 28%, ranging from zero to 100%. The likelihood of non-clinical T. parva infection was 35.5% greater in the western highlands compared to the northeastern semi-arid AEZs. Conclusions: Non-clinical T. parva occurs countrywide, structured along patterns of AEZ and breed gradients. These findings may guide policy formulation, deployment of integrated control strategies and local cattle improvement programs.
High Levels of Genetic Differentiation between Ugandan Glossina fuscipes fuscipes Populations Separated by Lake Kyoga
(PLoS Neglected Tropical Diseases, 2008) Abila, Patrick P.; Slotman, Michel A.; Parmakelis, Aristeidis; Dion, Kirstin B.; Robinson, Alan S.; Muwanika, Vincent B.; Enyaru, John C. K.; Lokedi, Loyce M.; Aksoy, Serap; Caccone, Adalgisa
Glossina fuscipes fuscipes is the major vector of human African trypanosomiasis, commonly referred to as sleeping sickness, in Uganda. In western and eastern Africa, the disease has distinct clinical manifestations and is caused by two different parasites: Trypanosoma brucei rhodesiense and T. b. gambiense. Uganda is exceptional in that it harbors both parasites, which are separated by a narrow 160-km belt. This separation is puzzling considering there are no restrictions on the movement of people and animals across this region. Methodology and Results: We investigated whether genetic heterogeneity of G. f. fuscipes vector populations can provide an explanation for this disjunct distribution of the Trypanosoma parasites. Therefore, we examined genetic structuring of G. f. fuscipes populations across Uganda using newly developed microsatellite markers, as well as mtDNA. Our data show that G. f. fuscipes populations are highly structured, with two clearly defined clusters that are separated by Lake Kyoga, located in central Uganda. Interestingly, we did not find a correlation between genetic heterogeneity and the type of Trypanosoma parasite transmitted. Conclusions: The lack of a correlation between genetic structuring of G. f. fuscipes populations and the distribution of T. b. gambiense and T. b. rhodesiense indicates that it is unlikely that genetic heterogeneity of G. f. fuscipes populations explains the disjunct distribution of the parasites. These results have important epidemiological implications, suggesting that a fusion of the two disease distributions is unlikely to be prevented by an incompatibility between vector populations and parasite.
Indigenous cattle breeds and factors enhancing their variation, potential challenges of intensification and threats to genetic diversity in Uganda
(Animal Genetic Resources, 2016) Kabi, Fredrick; Muwanika, Vincent B.; Masembe, Charles
Indigenous cattle support approximately 26.1 percent of Ugandan families through provision of food and income in addition to the supply of socio-cultural wealth and security. Cattle keepers have developed and maintained variations of indigenous cattle phenotypes and genotypes suited to their agro-ecological zones through traditional management practices and socio-cultural aspects. The Ankole (Bos taurus indicus), East African shorthorn Zebu (Bos indicus) and their crossbred cattle constitute the main indigenous breeds, adding up to 93.3 percent of the Ugandan herd. With intensions to increase productivity, state policies encourage livestock farmers to upgrade local genotypes towards high yielding exotic dairy cattle. This if not appropriately planned is likely to result into loss of local genetic diversity, well endowed with resilience to local climatic conditions, endemic diseases and feed resource constraints. Here in, we review literature related to indigenous cattle in Uganda including how diverse landscapes, local management practices and socio-cultural aspects have enriched patterns of indigenous cattle variations. Then we highlight potential challenges of intensive management, increased selection for higher productivity and threats to genetic diversity of indigenous cattle populations. Since indigenous cattlevary with landscapes and socio-cultural values, have taken decades to establish, efforts to save them through genetic diversity studies, conservation and farmers sensitization should be undertaken immediately
Involvement of key stakeholders in controlling animal diseases in rural settings: Experiences with African swine fever in Uganda
(African Journal of Agricultural Research, 2020) Ogweng, Peter; Masembe, Charles; Mayega, Johnson F.; Keeya, Ibrahim; Tumuhe, Charles; Okwasiimire, Rodney; Muwanika, Vincent B.
Key stakeholders’ involvement in the design and enforcement of effective African swine fever (ASF) biosecurity measures is very vital. Unfortunately, many times key stakeholders are less involved in the policy designing process. This study analyzed information from stakeholders in Mukono District, to assess the acceptability of enforcing ASF biosecurity measures among key stakeholders. Mukono District has a high density of pigs and a history of frequent ASF outbreaks. Key informants (n = 23) were identified and interviewed in four sub-counties to generate an ASF control stakeholders’ list. Eleven stakeholder groups were identified by the Key Informants. Sixty participants representing different stakeholder groups identified through the Key Informant interviews participated in a workshop to assess stakeholders’ characteristics regarding strict enforcement of ASF control measures. Stakeholder grid analysis revealed 60% as drivers, and 40% as supporters. There were no blockers, abstainers, and bystanders. Despite this, majority of the groups (90%) did not have adequate capacity to implement the intervention due to financial constraints and inadequate technical support. These results show that there is great support for enforcement of biosecurity measures if stakeholders are facilitated with financial and technical support thereby limiting outbreaks of ASF in rural areas of Uganda.
Laboratory capacity for diagnosis of foot-and-mouth disease in Eastern Africa: implications for the progressive control pathway
(BMC veterinary research, 2013) Namatovu, Alice; Wekesa, Sabenzia N.; Tjørnehøj, Kirsten; Dhikusooka, Moses T.; Muwanika, Vincent B.; Siegismund, Hans R.; Ayebazibwe, Chrisostom
Accurate diagnosis is pertinent to any disease control programme. If Eastern Africa is to work towards control of foot-and-mouth disease (FMD) using the Progressive Control Pathway for FMD (PCP-FMD) as a tool, then the capacity of national reference laboratories (NRLs) mandated to diagnose FMD should match this task. This study assessed the laboratory capacity of 14 NRLs of the Eastern Africa Region Laboratory Network member countries using a semi-structured questionnaire and retrospective data from the World Reference Laboratory for FMD annual reports and GenbankW through National Centre for Biotechnology Information for the period 2006–2010. Results: The questionnaire response rate was 13/14 (93%). Twelve out of the 13 countries/regions had experienced at least one outbreak in the relevant five year period. Only two countries (Ethiopia and Kenya) had laboratories at biosecurity level 3 and only three (Ethiopia, Kenya and Sudan) had identified FMD virus serotypes for all reported outbreaks. Based on their own country/region assessment, 12/13 of these countries /regions were below stage 3 of the PCP-FMD. Quarantine (77%) and vaccination (54%) were the major FMD control strategies employed. The majority (12/13) of the NRLs used serological techniques to diagnose FMD, seven used antigen ELISA and three of these (25%) also used molecular techniques which were the tests most frequently requested from collaborating laboratories by the majority (69%) of the NRLs. Only 4/13 (31%) participated in proficiency testing for FMD. Four (31%) laboratories had no quality management systems (QMS) in place and where QMS existed it was still deficient, thus, none of the laboratories had achieved accreditation for FMD diagnosis. Conclusions: This study indicates that FMD diagnostic capacity in Eastern Africa is still inadequate and largely depends on antigen and antibody ELISAs techniques undertaken by the NRLs. Hence, for the region to progress on the PCP-FMD, there is need to: implement regional control measures, improve the serological diagnostic test performance and laboratory capacity of the NRLs (including training of personnel as well as upgrading of equipment and methods, especially strengthening the molecular diagnostic capacity), and to establish a regional reference laboratory to enforce QMS and characterization of FMD virus containing samples.
Molecular characterization of SAT 2 foot-and-mouth disease virus from post-outbreak slaughtered animals: implications for disease control in Uganda
(Epidemiology & Infection, 2010) Balinda, Sabenzia N.; Belsham, Graham J.; Masembe, Charles; Sangula, Abraham K.; Siegismund, Hans R.; Muwanika, Vincent B.
In Uganda, limiting the extent of foot-and-mouth disease (FMD) spread during outbreaks involves short-term measures such as ring vaccination and restrictions of the movement of livestock and their products to and from the affected areas. In this study, the presence of FMD virus RNA was investigated in cattle samples 3 months after FMD quarantine measures had been lifted following an outbreak in 2004. Oropharyngeal tissue samples were obtained from 12 cattle slaughtered in a small town abattoir in Kiboga. FMD virus RNA was detected by diagnostic RT–PCR in nine of the 12 tissue samples. Part of the coding region for the capsid protein VP1 was amplified and sequenced. All samples were identified as belonging to the SAT 2 serotype. The implications for FMD control of both virus introduction into Uganda and the presence of carrier animals following outbreaks are discussed.
Nutritional properties of some browse species used as goat feed in Pastoral dry lands, Uganda
(Agroforestry Systems, 2020) Nsubuga, David; Nampanzira, Dorothy K.; Masembe, Charles; Muwanika, Vincent B.
The nutritional properties of leaves of ten browse species commonly used as goat feed in pastoral drylands of Uganda were evaluated by determining their chemical composition and in vitro gas production. Dry matter (DM) content ranged between 896 and 914 g kg-1 DM and was not significantly different (P[0.05) among the browse species. There was a wide variation in the crude protein (CP) content of the browse species. The highest CP values were observed in Acacia compylacantha, Acacia fruiticosa and Acacia senegal, with 365, 247 and 245 g kg-1 DM respectively, while the lowest was observed in Ganisa similis (150 g kg-1 DM). The NDF values were highest in A. senegal (343 g kg-1 DM) and lowest in A. compylacantha (151 g kg-1 DM). There was no significant difference (P[0.05) in the gas kinetics and total volume of gas produced by the browse species.

Browsing by Author "Muwanika, Vincent B."

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