Effect of biotic and abiotic factors on composition and foraging intensity of subterranean termites

Elucidating the influence of ecological factors on composition and foraging intensity of subterranean termites is critical in development of sustainable termite management strategies. Our aim was therefore to analyze the effect of selected biotic and abiotic factors on composition and foraging intensity of termites. We used principal component and canonical correspondence analysis to select appropriate factors and to model relationships respectively. Macrotermes species occurred in sites where the quantity of litter was generally above the mean. However, Macrotermes herus (Rambur) and Macrotermes spp.4 occurred in sites where the litter quantity was below the mean. Trinervitermes oeconomous (Tragardh) and Odontoremes spp.1 were noted to occur in the direction of increasing quantity of biomass. Generally, most species occurred in sites where soil pH was above or slightly below the mean (4.8). Majority of the species were also noted to occur in sites where bulk density was below or slightly above the mean (1.55 g/cm3). Highest bait consumption (95%) occurred within a range of 55 to 60% basal cover beyond which the amount of bait consumed reduced. Litter and biomass quantity, pH and bulk density were noted as the most influential environmental variables determining composition of termites while basal cover was the major determinant of foraging intensity.Key words: Rangelands, Macrotermes, rangelands, vegetation, litter, biomass, basal-cover

Integrated termite management for improved rainwater management: A synthesis of selected African experiences

In eastern Africa, termites are perceived by farmers, livestock keepers, and many development agencies as serious agricultural pests that destroy pasture, crops and wooden infrastructure. Commonly use control measures have proven to be ineffective. When the CGIAR Challenge Program on Water and Food (CPWF) undertook research aimed at increasing agricultural water productivity in eastern Africa, termites destroyed early experiments designed to rehabilitate degraded land and increase water productivity. Building on indigenous knowledge from termite affected regions of Ethiopia, the CPWF and Uganda partners initiated research on integrated termite management. Results were promising. This literature review was commissioned to capture the state-of-knowledge about termite taxonomy, and diversity, farmers’ ethno-ecological knowledge of subterranean termites and termite management practices and control measures used in African crop and rangeland production systems. The paper offers some general lessons and guidelines for future agricultural research and development programs where termite damage is problematic. In brief, we conclude that ITM offers greater prospects for enabling termites to play important positive roles in agro-ecosystem functioning while reducing the damage they inflict on crop and livestock production

LAND USE AND COVER CHANGE IN PASTORAL SYSTEMS OF UGANDA: IMPLICATIONS ON LIVESTOCK MANAGEMENT UNDER DROUGHT INDUCED PASTURE

The rangelands of Uganda used to be historically managed under traditional systems where grazers had open access with mobility as a main coping strategy to drought. Changes in land ownership, increased population and demand for food and fuel have led to changes in land use and cover types, affecting livestock management practices. This study assessed the extent of land use and cover change in Buliisa and Nakasongola Districts in the cattle corridor of Uganda over 27 years (1986 \u20132013), and their impacts on livestock management under drought induced pasture. Landsat TM (1986) and Landsat ETM+ (2000 and 2013) images were processed using a hybrid of supervised and unsupervised classification algorithm, using ENV1 software 4.7. Area under open water and grassland declined by 3.5 and 48.3%, while woodland, wetland, small scale farming and forest increased by 0.2, 62.2, 320.7 and 64.1%, respectively, in Buliisa. In Nakasongola, grassland, bushland and forest decreased by 96.1, 25.6 and 17.2%, respectively; while open water, bare ground, wetland, and small scale farming increased by 5.3, 210.9, 2.7 and 26.8%, respectively, between 1986 and 2013. Individualisation of land in Nakasongola led to settlement of cultivators and fencing of land leading to blockage of livestock migration routes. Reduced mobility of livestock during drought, increased stock densities resulting in land degradation exemplified by bare land in Nakasongola compared to Buliisa, where communal land ownership and limited cultivation enabled mobility. The current land use and cover changes have delineated mobility as a coping strategy to drought, contributed to degradation of rangelands, reduced the resilience of pastoral systems to drought and increased their vulnerability to climate change. Farm based water and forage conservation should be enhanced to sustain livestock production.Les p\ue2turages de l\u2019 Ouganda \ue9taient historiquement g\ue9r\ue9s sous syst\ue8me traditionnel o\uf9 les \ue9leveurs avaient un acc\ue8s facile avec libre mouvement comme strat\ue9gie d\u2019adaptation aux conditions de s\ue9cheresse. Les changements dans les syst\ue8mes de propri\ue9te fonci\ue8re , l\u2019augmentation de la population et la demande accrue de la nourriture et produits de chauffe ont induit des changements dans l\u2019utilisation des terres et types de couvert, affectant ainsi les pratiques de gestion de l\u2019\ue9levage. Cette \ue9tude a \ue9valu\ue9 l\u2019ampleur du changement dans l\u2019utilisation des terres et couvert v\ue9g\ue9tal dans les districts de Buliisa et Nakasongola dans le corridor du b\ue9tail en Ouganda depuis 27 ans (1986 \u20132013), et leurs impacts sur la gestion de l\u2019\ue9levage en conditions de s\ue9cheresse. Les images Landsat TM (1986) et ETM+ (2000 et 2013) \ue9taient exploit\ue9es par utilisation d\u2019un m\ue9lange d\u2019algorithme de classification supervis\ue9e ou non supervis\ue9e utilisant le logiciel 4.7 ENV1. Les surfaces d\u2019eau et les p\ue2turages ont diminu\ue9 de 3.5 et 48.3%, pendant que les zonesz bois\ue9es , les marrais, les surfaces cultiv\ue9es et les forets ont augment\ue9 de 0.2, 62.2, 320.7 et 64.1%, respectivement, dans Buliisa. Dans la r\ue9gion de Nakasongola, les p\ue2turages, les terres sur-brulis et les forets ont diminu\ue9 de 96.1, 25.6 et 17.2% respectivement; pendant que les surfaces d\u2019eau, les surfaces d\ue9nud\ue9es , les marrais et les surfaces cultiv\ue9es ont augment\ue9 de 5.3, 210.9, 2.7 et 26.8%, respectivement, entre 1986 et 2013. La privatisation des terres \ue0 Nakasongola a conduit \ue0 l\u2019occupation des terres par les cultivateurs, restreignant ainsi les mouvement migratoire du b\ue9tail. Cette r\ue9duction de la mobilit\ue9 du b\ue9tail durant la saison s\ue8che a entrain\ue9 une augmentation de leur densit\ue9 entrainant une d\ue9gradation avec d\ue9nudation des terres en comparaison avec Buliisa, o\uf9 l\u2019utilisation des terres communales et l\u2019activit\ue9 agricole limit\ue9e ont facilit\ue9 la mobilit\ue9. L\u2019utilisation actuelle des terres et les changements du couvert v\ue9g\ue9tal ont renforc\ue9 la mobilit\ue9 du b\ue9tail comme strat\ue9gie d\u2019adaptation \ue0 la s\ue9cheresse, contribu\ue9 \ue0 la d\ue9gradation des p\ue2turages, r\ue9duit la r\ue9silience des syst\ue8mes pastoraux \ue0 la s\ue9cheresse et augment\ue9 leur vuln\ue9rabilit\ue9 au changement climatique. La conservation du fourrage et de l\u2019eau au niveau des exploitations devrair \ueatre renforc\ue9e pour permettre un \ue9levage durable

Genome-wide diversity and structure variation among lablab [Lablab purpureus (L.) Sweet] accessions and their implication in a forage breeding program

Open Access Article; Published online: 19 Mar 2021Most orphan crops have not been fully sequenced, hence we rely on genome sequences of related species to align markers to different chromosomes. This hinders their utilisation in plant population improvement programs. Utilising the advances in the science of sequencing technologies, the population structure, relatedness, and genetic diversity among accessions can be assessed quickly for better exploitation in forage breeding programs. Using DArTseq technology, we studied the genetic and structural variation in 65 Lablab purpureus (L.) Sweet conserved gene-bank accessions using 9320 DArTseq-based SNPs and 15,719 SilicoDart markers. These markers had a low discriminating ability with mean polymorphic information content (P.I.C.) of 0.14 with DArTseq-based SNPs and 0.13 with SilicoDart markers. However, the markers had a high mean call rate of 73% with DArTseq-based SNPs and 97% with SilicoDart markers. Analysis of molecular variance revealed a high within populations variance (99.4%), indicating a high gene exchange or low genetic differentiation (PhiPT = 0.0057) among the populations. Structure analysis showed three allelic pools in variable clusters of ΔK = 3 and 6. Phylogenetic tree of lablab accessions showed three main groups with variable membership coefficients. Most pairs of accessions (40.3%) had genetic distances between 0.10 and 0.15 for SilicoDart markers, while for DArTseq-based SNPs, (46.5%) had genetic distances between 0.20 and 0.25. Phylogenetic clustering and minimum spanning analysis divided the 65 accessions into three groups, irrespective of their origin. For the first time, this study produced high-density markers with good genom coverage. The utilisation of these accessions in a forage program will base on the information from molecular-based grouping. The outcomes uncovered the presence of noteworthy measure of variety in Uganda, CIAT and ILRI accessions, thus demonstrating an opportunity for further marker-trait-association studies

On the scaling of activity in tropical forest mammals

Activity range – the amount of time spent active per day – is a fundamental aspect contributing to the optimization process by which animals achieve energetic balance. Based on their size and the nature of their diet, theoretical expectations are that larger carnivores need more time active to fulfil their energetic needs than do smaller ones and also more time active than similar‐sized non‐carnivores. Despite the relationship between daily activity, individual range and energy acquisition, large‐scale relationships between activity range and body mass among wild mammals have never been properly addressed. This study aimed to understand the scaling of activity range with body mass, while controlling for phylogeny and diet. We built simple empirical predictions for the scaling of activity range with body mass for mammals of different trophic guilds and used a phylogenetically controlled mixed model to test these predictions using activity records of 249 mammal populations (128 species) in 19 tropical forests (in 15 countries) obtained using camera traps. Our scaling model predicted a steeper scaling of activity range in carnivores (0.21) with higher levels of activity (higher intercept), and near‐zero scaling in herbivores (0.04). Empirical data showed that activity ranges scaled positively with body mass for carnivores (0.061), which also had higher intercept value, but not for herbivores, omnivores and insectivores, in general, corresponding with the predictions. Despite the many factors that shape animal activity at local scales, we found a general pattern showing that large carnivores need more time active in a day to meet their energetic demands. Introduction Activity range – the amount of time, in hours, spent active per day – is a fundamental outcome of the complex physiological and behavioral optimization process by which animals ensure that energy input keeps pace with energy output. In addition to basal metabolism, animals face costs of foraging, acquiring mates and shelter, building reserves for lean times and escaping predators (Carbone et al. 2007, Halle and Stenseth 2012). Environmental and ecological factors that vary through the day (e.g. luminosity, temperature, predation risk and competition avoidance) constrain activity to certain times, depending on morpho‐physiological limitations (Castillo‐Ruiz et al. 2012, Hut et al. 2012). In addition, animals need time to rest in order to recover their cognitive or physical condition (Siegel 2005). Thus, they must optimize their activity range to meet their resource requirements, while dealing with natural daily cycles and saving time for sleep/rest (Downes 2001, Siegel 2005, Cozzi et al. 2012). The resource requirements of mammals are related to basal metabolic rate, which scales positively with body mass (Kleiber 1932, Isaac and Carbone 2010), while predation risk decreases with body mass (Sinclair et al. 2003, Hopcraft et al. 2009). Because high predation risk constrains activity while high resource needs increases activity range (Cozzi et al. 2012, Suselbeek et al. 2014), the question arises whether and how activity range also scales with body mass. Day range (total distance travelled in a day) and home range (area in which animals perform their daily activities) scales positively with body mass and are key metrics to understand the resource requirements of an animal (McNab 1963, Kelt and Van Vuren 2001, Carbone et al. 2005, Tamburello et al. 2015). As activity range is related to space‐use metrics (i.e. home range and day range), it is hence, also related to the acquisition of energy. Given that, one might expect activity range to increase with body mass. However, we have a poor understanding of how this relationship actually looks. Previous work developed predictions of body mass scaling with day range (Garland 1983, Carbone et al. 2005) and travel speed (Carbone et al. 2007, Rowcliffe et al. 2016). From a simple physical viewpoint, activity range should equal the day range divided by average travel speed. It should thus be possible to infer the scaling of activity range with body mass from these relationships. Some of the variation in space use across species that is not explained by body mass is associated with different evolutionary histories and ecological traits (McNab 1963, Kelt and Van Vuren 2001, Price and Hopkins 2015, Tamburello et al. 2015). Diet is the most conspicuous of these, because primary and secondary productivity present different overall yields and accessibility for consumers (Jetz et al. 2004), which in turn influence individual movements (Carbone et al. 2005) and potentially activity range, when exploiting resources at different trophic levels. The nature of the diet aggravates the higher energetic demands of larger carnivores. Predators have considerable energetic constraints related to hunting and handling their prey (Gorman et al. 1998, Carbone et al. 1999) as animal prey can be rare, widely dispersed, unpredictable in time and space and not storable (Jetz et al. 2004, Carbone et al. 2007). Therefore, carnivores have the lowest energy supply rates (supply rate of usable resources available inside the home range), independent of body mass, when compared to other diet categories (Jetz et al. 2004) besides exploring larger areas and traveling greater daily distances (McNab 1963, Kelt and Van Vuren 2001, Carbone et al. 2005, Tamburello et al. 2015). Therefore, larger animals occupy larger areas than small ones, and carnivores occupy larger areas than do similar‐sized non‐carnivores (Jetz et al. 2004, Tamburello et al. 2015). To date, few studies have considered interspecific variation in activity range with body mass and other species traits. For example, van Schaik and Griffiths (1996) and Gómez et al. (2005) anecdotally suggested that larger mammal species are cathemeral (i.e. active day and night), which implies that they can be active during a larger proportion of the 24‐h cycle. Rowcliffe et al. (2014) found that activity range is positively correlated with body mass in tropical forest mammals in Panama. Ramesh et al. (2015) found a negative relationship between body mass and activity concentration (i.e. how concentrated in few hours is the activity of an animal during the day) in Indian mammals, also equating to a positive association between activity range and body mass. However, no study has explored variation in activity range across a diverse range of species, while controlling for phylogeny and diet. This has been, at least in part, due to a lack of consistent data available on a wide range of species. Recent work using camera traps (Oliveira‐Santos et al. 2013, Rowcliffe et al. 2014), however, has demonstrated that accurate estimates of activity range can be obtained from photographic records from camera traps. Given the large and rapidly increasing volume of camera‐trapping data available globally (Burton et al. 2015), these approaches, consistently applied across a wide range of studies, can provide an important basis for the large‐scale study of activity. Here, we provided simple empirical predictions for the scaling of activity range with body mass for mammals of different trophic guilds. To test these predictions, we estimated the activity range for 249 populations of 128 terrestrial mammal species across 19 tropical forests, and used a phylogenetically controlled mixed model to determine how activity range scales with body mass by diet. As larger animals occupy larger areas than small ones, and carnivores occupy larger areas than do similar‐sized non‐carnivores (Jetz et al. 2004), we hypothesize that carnivores will present a higher scaling of activity range with body mass and also higher activity ranges for a given mass (higher intercept) when compared to herbivores, omnivores and insectivores

Indigenous Grasses for Rehabilitating Degraded African Drylands

Drylands provide an important livelihood stream to its inhabitants across the globe through a range of products and ecosystem services. However, these fragile ecosystems are threatened and believed to experience various degrees of land degradation. Estimates of the landmass affected by land degradation in the global drylands range from 10% to 20%, a percentage that is increasing at an annual global rate of 12 million ha of soil lost from desertification and drought. African drylands are especially highly susceptible to severe degradation because of their poor soil structure aggravated by scarce vegetation cover. Causes of degradation in these environments are both natural and anthropogenic in nature. Change in vegetation cover, decline in soil fertility, biodiversity loss and soil erosion demonstrate degradation in African drylands. Grass reseeding using indigenous species is one of the promising sustainable land management strategies to combat degradation in the drylands. Reseeding programmes are aimed at improving vegetation cover and biomass, and they conserve the soil to an extent not possible by grazing and land management alone. Indigenous drought-tolerant grasses notably African foxtail grass (Cenchrus ciliaris), bush rye grass (Enteropogon macrostachyus) and Maasai lovegrass (Eragrostis superba) have produced promising rehabilitation outcomes. Previous studies in African drylands have demonstrated the potential of such indigenous forage grasses in improving both vegetation cover (plant frequency and densities, basal cover) and soil hydrological properties (increased infiltration capacity, reduced runoff and sediment production) as indicators of rehabilitation success. Despite their comparative and widespread success, natural and anthropogenic challenges persist. This makes reseeding programmes a risky and often expensive venture, especially for the resource-poor pastoral communities in African drylands. Despite the risks, grass reseeding using indigenous pastures remains a viable sustainable land management option to combat degradation in African drylands. However, to ensure its continued success in the long term, multifaceted approaches and strategies that will integrate land and water management and seed systems suitable for African drylands need to be developed, strengthened and promoted.Peer reviewe

Treatment outcomes of new tuberculosis patients hospitalized in Kampala, Uganda: a prospective cohort study.

BACKGROUND: In most resource limited settings, new tuberculosis (TB) patients are usually treated as outpatients. We sought to investigate the reasons for hospitalisation and the predictors of poor treatment outcomes and mortality in a cohort of hospitalized new TB patients in Kampala, Uganda. METHODS AND FINDINGS: Ninety-six new TB patients hospitalised between 2003 and 2006 were enrolled and followed for two years. Thirty two were HIV-uninfected and 64 were HIV-infected. Among the HIV-uninfected, the commonest reasons for hospitalization were low Karnofsky score (47%) and need for diagnostic evaluation (25%). HIV-infected patients were commonly hospitalized due to low Karnofsky score (72%), concurrent illness (16%) and diagnostic evaluation (14%). Eleven HIV uninfected patients died (mortality rate 19.7 per 100 person-years) while 41 deaths occurred among the HIV-infected patients (mortality rate 46.9 per 100 person years). In all patients an unsuccessful treatment outcome (treatment failure, death during the treatment period or an unknown outcome) was associated with duration of TB symptoms, with the odds of an unsuccessful outcome decreasing with increasing duration. Among HIV-infected patients, an unsuccessful treatment outcome was also associated with male sex (P = 0.004) and age (P = 0.034). Low Karnofsky score (aHR = 8.93, 95% CI 1.88 - 42.40, P = 0.001) was the only factor significantly associated with mortality among the HIV-uninfected. Mortality among the HIV-infected was associated with the composite variable of CD4 and ART use, with patients with baseline CD4 below 200 cells/µL who were not on ART at a greater risk of death than those who were on ART, and low Karnofsky score (aHR = 2.02, 95% CI 1.02 - 4.01, P = 0.045). CONCLUSION: Poor health status is a common cause of hospitalisation for new TB patients. Mortality in this study was very high and associated with advanced HIV Disease and no use of ART

Men??s circumcision status and women??s risk of HIV acquisition in Zimbabwe and Uganda

OBJECTIVE: To assess whether male circumcision of the primary sex partner is associated with women's risk of HIV. DESIGN: Data were analyzed from 4417 Ugandan and Zimbabwean women participating in a prospective study of hormonal contraception and HIV acquisition. Most were recruited from family planning clinics; some in Uganda were referred from higher-risk settings such as sexually transmitted disease clinics. METHODS: Using Cox proportional hazards models, time to HIV acquisition was compared for women with circumcised or uncircumcised primary partners. Possible misclassification of male circumcision was assessed using sensitivity analysis. RESULTS: At baseline, 74% reported uncircumcised primary partners, 22% had circumcised partners and 4% had partners of unknown circumcision status. Median follow-up was 23 months, during which 210 women acquired HIV (167, 34, and 9 women whose primary partners were uncircumcised, circumcised, or of unknown circumcision status, respectively). Although unadjusted analyses indicated that women with circumcised partners had lower HIV risk than those with uncircumcised partners, the protective effect disappeared after adjustment for other risk factors [hazard ratio (HR), 1.03; 95% confidence interval (CI), 0.69-1.53]. Subgroup analyses suggested a non-significant protective effect of male circumcision on HIV acquisition among Ugandan women referred from higher-risk settings: adjusted HR 0.16 (95% CI, 0.02-1.25) but little effect in Ugandans (HR, 1.33; 95% CI, 0.72-2.47) or Zimbabweans (HR, 1.12; 95% CI, 0.65-1.91) from family planning clinics. CONCLUSIONS: After adjustment, male circumcision was not significantly associated with women's HIV risk. The potential protection offered by male circumcision for women recruited from high-risk settings warrants further investigation

Whole Blood Interferon-Gamma Responses to Mycobacterium tuberculosis Antigens in Young Household Contacts of Persons with Tuberculosis in Uganda

Due to immunologic immaturity, IFN-gamma-producing T cell responses may be decreased in young children compared to adults, thus we hypothesized that IFN-gamma responses to mycobacterial antigens in household contacts exposed to Mycobacterium tuberculosis (Mtb) would be impaired in young children relative to adults. The objective of this study was to compare whole blood IFN-gamma production in response to mycobacterial antigens between children and adults in Uganda.We studied household contacts of persons with culture-positive pulmonary tuberculosis (TB) enrolled in a cohort study conducted in Kampala, Uganda. Whole blood IFN-gamma production in response to Mtb culture-filtrate antigens was measured by ELISA and compared between infants (<2 years old, n = 80), young children (2 <5 years old, n = 216), older children (5 <15 years old, n = 443) and adults (> or =15 years old, n = 528). We evaluated the relationship between IFN-gamma responses and the tuberculin skin test (TST), and between IFN-gamma responses and epidemiologic factors that reflect exposure to Mtb, and the effect of prior BCG vaccination on IFN-gamma responses. Young household contacts demonstrated robust IFN-gamma responses comparable to those of adults that were associated with TST and known risk factors for infection. There was no effect of prior BCG immunization on the IFN-gamma response.Young children in a TB endemic setting can mount robust IFN-gamma responses generally comparable to those of adults, and as in adults, these responses correlated with the TST and known epidemiologic risk factors for Mtb infection