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Predatory effects on the dynamics of Spodoptera Frugiperda infestations in maize
Get PDFThis Research Article was published by the Informatics in Medicine Unlocked
Volume 42, 2023,Maize remains in demand due to its nutritive value, capacity to provide food for a growing world population, contribution to food security, and increase in worldwide investments in ethanol as a biofuel. However, the invasion and widespread infestation of Spodoptera frugiperda result in significant maize yield losses, leading to a lower standard of living and a weakened economy for maize producers. This study builds differentiable equations to simulate the behavior of the Spodoptera frugiperda-maize biomass model, incorporating predators and best farming practices. The model exhibits six points of equilibrium, all of which are locally asymptotically stable if the necessary requirements are met. Latin Hypercube Sampling (LHS) and PRCC multivariate analysis were employed to identify the sensitive parameters affecting the pest. Numerical simulations suggest that, in the early stages, integrating natural enemies with best farming practices proves to be an effective intervention as it directly reduces the pest population and promotes sustainable pest control
Community antibiotic usage and the characterization of antibiotic resistance among common bacterial isolates in selected rural and urban districts of the DODOMA Region, Central TANZANIA
Get PDFA Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of
Doctor of Philosophy in Life Sciences of the Nelson Mandela African Institution of
Science and TechnologyAntibiotic resistance threatens the treatment of bacterial infections globally. This cross-
sectional study was conducted from August 2019 to May 2021 in Dodoma. The aim was to
understand the prevalence and determinants of self-medication with antibiotics (SMA),
antibiotic dispensing in community drug outlets, antibiotic prescribing in primary health care
facilities and determine resistance profiles of bacterial pathogens in primary health care
facilities (PHCF). Regarding SMA, 430 respondents were interviewed in Chemba District
Council (rural) (161/430) and Dodoma City Council (urban) (269/430). The prevalence of
SMA was 23.6% (38/161) and 23.4% (63/269) in the rural and urban respondents respectively.
A shorter perceived distance to a health care facility than to a drug outlet was associated with
decreased SMA practices among participants. Furthermore, 643 drug purchases were recorded
in Accredited Drug Dispensing Outlets (ADDO) and community pharmacies, 84.1 % (541/643)
were in Dodoma City Council (urban) and only 24.9% (160/643) purchased antibiotics.
Antibiotics were dispensed in ADDO without prescriptions and beyond jurisdiction. Children
<5 years accounted for over 45% (474/1021) of all the consultations recorded in the primary
health care facility (PHCF); 76.3% (779/1021) of the consultations had an antibiotic with up to
55% (429/779) adherence to Standard Treatment Guidelines (STG). Pneumonia and respiratory
symptoms were 16 times (adjusted OR=15.918; 95% CI: 2.151, 17.973; p = 0.007) and almost
2 times (adjusted OR=1.709; 95% CI: 1.129, 2.587; p = 0.011) more likely to prompt
antibiotics, respectively. Furthermore, 621 clinical specimens were collected from out-patients
in Chemba District Council (38.1%; 237/621) and Dodoma City Council (61.9%; 384/621)
respectively. S. aureus (44) and E. coli (35) were the most prevalent isolates. There were high
resistance rates of E. coli and S. aureus against ampicillin, ciprofloxacin and
trimethoprim/sulfamethoxazole: 31.8% (14/44) of S. aureus were methicillin-resistant
(MRSA). This study reports high SMA among those living close to community drug outlets,
high un-prescribed antibiotic dispensing in ADDO, poor adherence to STG and relatively lower
methicillin-resistant Staphylococcus aureus (MRSA) levels in PHCF. The study calls for more
concerted efforts against the misuse of antibiotics as a means of confronting the emergence and
spread of antibiotic resistance
Epidemiologic study of q fever in smallholder dairy cattle in selected regions of Tanzania
Get PDFA Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of
Master’s in Health and Biomedical Sciences of the Nelson Mandela African Institution
of Science and TechnologyA cross-sectional study was conducted to determine prevalence and the risk factors associated
with Coxiella burnetii seropositivity in smallholder dairy cattle in six regions from the southern
highland and northern zones of Tanzania between July 2019 and October 2020. A total of 2049
blood samples and 1920 vaginal swabs were collected from dairy cattle. Serum was tested for
antibodies against C. burnetii using an indirect enzyme-linked immunosorbent assay (ELISA).
C. burnetii DNA was identified from vaginal swabs using quantitative polymerase chain
reaction (qPCR) analyses. A questionnaire survey was designed and uploaded to the Open
Data Kit (ODK) cloud platformsoftware version 1.22.4. At each household, the cattle owner
aging equal or over 18 years was interviewed to understand the risk factors related to animal
health, husbandry, and farmer socioeconomics, as well as environmental variables. C. burnetii
prevalence was calculated at different epidemiological levels and maps were created to
visualize Q fever spatial distribution. Logistic generalized linear mixed effects models were
built to explorethe association between ELISA binomial results, and a set of risk factors and
environmental variables important for C. burnetii occurrence. An overall animal
seroprevalence of 3.86% (79, 2049) 95% CI 3.06 - 4.78 was estimated across the study regions.
Among these regions, Tanga (northern zone) and Iringa (southern zone) showed the highest
prevalence with 8.21% (95% CI 6.0 - 10.89%) and 4.63% (95% CI: 2.49 - 7.78%) respectively.
On the other hand, molecular identification of C. burnetii from vaginal swabs of selected cows
revealed an overall prevalence of 0.94% (18,1920) (95% CI 0.5-1.4%). Among the northern
zone regions, Arusha had the highest of 2.3%(95%CI 0.9-4.7%) and on the southern highlands
zone, Iringa emanated to have the highest prevalence of 0.73% (95%CI 0.08-2.5%). Animal
age, extensive feeding system, and temperature were univariably significant risk factors to C.
burnetii seropositivity. The final multivariable logistic regression model showed that old
animal age, extensive feeding system, and low precipitation were strongly associated with Q
fever seropositivity. These findings indicate that C. burnetii circulates among smallholder dairy
cattle across regions in Tanzania. However, Tanga, Arusha and Iringa are the three regions with
the highest seroprevalence and should be considered for systematic and active surveillance.
Furthermore, “One Health” approaches are necessary to fully understand disease transmission
and control of this zoonotic disease
Screening and evaluation of salinity stress tolerance in local malawian tomato Cultivars
Get PDFThis research article was published in the Plant Physiology Reports, Volume 28, pages 259–271, 2023Unravelling how crop plants respond to salinity stress, and their underlying morphological and physiological adaptations could provide benchmarks for development of crop improvement programs in salt affected regions. The purpose of this study was to screen for tolerance and identify morpho-physiological traits underlying salinity tolerance in locally adapted tomato (Solanum lycopersicum L.) cultivars. Six (6) popular Malawian tomato cultivars with unknown response to salinity stress were evaluated under greenhouse conditions by gradual exposure to 200 mM NaCl for 21 days. Shoot and root growth were markedly reduced in all cultivars after 21 days of salt stress. Derivation of stress susceptibility index (SSI) showed lowest and highest values in Mbambande (tolerant) and Phindu (sensitive) cultivars, respectively. The tolerant cultivar exhibited higher crop growth rate, relative growth rate and net assimilation rate but lower leaf area ratio and specific leaf area compared to the sensitive cultivar. Also, it reduced accumulation of Na+ to the leaves, but increased K+ accumulation, resulting into higher K+/Na+ ratios. Furthermore, the tolerant cultivar developed morphologically thicker leaves, that are described to necessitate Na+ sequestration, and also experienced the least salinity induced senescence (SIS). The most crucial morpho-physiological traits contributing to genotypic differences in salinity tolerance in the cultivars were found to be (1) enhanced leaf and root K+ accumulation (2) leaf Na+ exclusion and consequent higher K+/Na+ ratios, (3) development of thicker leaves, and (4) maintenance of root membrane integrity. Consideration of these traits in tomato breeding programs may provide some much-needed gains for salt tolerance
Health professionals’ knowledge on dengue and health facility preparedness for case detection: A cross-sectional study in Dar es Salaam, TanzaniaHealth professionals’ knowledge on dengue and health facility preparedness for case detection: A cross-sectional study in Dar es Salaam, Tanzania
Get PDFA research article was published by PLOS Neglected Tropical Diseases, Volume 17 | November 21, 2023Dengue presents a growing public health concern in the Dar es Salaam region of Tanzania, marked by the recurring incidence of outbreaks. Unfortunately, there is little information available on the region’s preparedness in terms of health care workers’ knowledge on dengue as well as the availability of reagents and equipment essential for diagnosing and monitoring of dengue infections. To elucidate this, 78 health facilities were visited in Temeke district and structured questionnaires were distributed to 324 health care workers. The aim was to evaluate health care workers’ knowledge on dengue and to assess the availability of reagents and equipment essential for diagnosing and monitoring of dengue infections. Content validity of the questionnaire was achieved through extensive literature review and it exhibited high reliability (Cronbach Alpha coefficient = 0.813). Cumulative scores for responses on knowledge questions by health care workers were computed. Characteristics such as level of education, place of work and gender were tested for association with these scores using chi-square tests and logistics regression. Almost all health care workers (99.7%) were aware of dengue disease. However, less than half (46.9%) had knowledge scores of or over 40%. Clinicians had approximately four times higher knowledge scores than other cadres (AOR, 3.637; p-value≤ 0.0001), and those who worked in private facilities had twice the knowledge score than those working in government institutions (AOR, 2.071; p-value = 0.007). Only 8.6%, 35.6% and 14.7% of respondents reported the availability of dengue rapid tests, medical guidelines and refresher training respectively, showing a lack of health facilities readiness for the detection of dengue infections. Based on findings from this study, we recommend government authorities to build capacity of health care workers, to improve their understanding of dengue. We also urge the government and stakeholders to work together to ensure availability of diagnostic tests and other tools needed for diagnosis and surveillance of dengu
Chitosan-coated liposomes of Carrisa spinarum extract: synthesis, analysis and anti-pneumococcal potency
Get PDFThis research article was published by ICE Publishing, 2023In the present study, a chitosan (CS)-coated liposome (LipCsP-Chitosan) nanocarrier was fabricated for the delivery of Carissa spinarum (CsP) polyphenols to improve bioavailability and anti-pneumococcal potential against Klebsiella pneumoniae. LipCsP-Chitosan was synthesized by the ion gelation method and characterized by using a Malvern zetasizer and Fourier Transform Infrared (FTIR); CsP encapsulation and release kinetics were investigated. Anti-pneumococcal activity of the nanoformulations was accessed by agar-well diffusion and microdilution assays. LipCsP-chitosan exhibited a hydrodynamic size and zeta potential of 365.22 ± 0.70 nm and +39.30 ± 0.61 mV, respectively. CsP had an encapsulation efficiency of 81.5%. FTIR analysis revealed the interaction of the liposomes with chitosan and the CsP. A biphasic CsP release profile followed by a sustained release pattern was observed. LiPCsP-Chitosan presented a higher bioaccessibility of polyphenols in the simulated gastric phase (74.1% ± 1.3) than in the simulated intestinal phase (63.32% ± 1.00). LipCsP-chitosan had a relative inhibition zone diameter of 84.33% ± 2.51 when compared to CsP. At minimum inhibition concentration of 31.25 mg/mL, LipCsP-Chitosan reduced the viability of Klebsiella pneumoniae by 57.45% ± 3.76 after 24 h. The results obtained from the current study offer a new approach to the utilization of LipCsP-Chitosan as nanocarriers for candidate anti-pneumococcal agents
Influence of farmers’ socio-economic characteristics on nutrient flow and implications for system sustainability in smallholdings: a review
Get PDFThis research article was published by Frontiers in Soil Science in 2023The rise in global human population, coupled with the effects of climate change, has increased the demand for arable land. Soil fertility has been the most affected, among other things. Many approaches to soil fertility management have been proposed by studies in Sub-Saharan Africa (SSA); however, the question of sustainability remains. Nutrient monitoring (NUTMON), which combines biophysical and socio-economic features for soil fertility management, gives an in-situ soil fertility status of a given land use system, which ultimately provides guidance in proposing appropriate soil management techniques in a given land use system. In this review, the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) approach was deployed for a systematic search of the literature materials. The review evaluated various studies on nutrient monitoring in SSA soils in order to understand the socioeconomic attributes and their influence on farming systems, as well as nutrient flow and balances. The review identified two dominant smallholder farming systems in SSA: mixed crop-livestock and mixed crop farming systems. Also, this review revealed that most nutrient balance studies in SSA have been done in mixed crop and livestock farming systems. However, regardless of the farming systems, the overall mean nutrient balances in all studies, particularly those of nitrogen (N) and potassium (K), were negative, indicating significant nutrient mining. The review further revealed a vast range of biophysical soil fertility management technologies; however, their adoption has been limited by socio-economic aspects including land ownership, gender, financial position, literacy level, and access to inputs. Therefore, in view of this situation, integrating biophysical and socioeconomic disciplines could address the problem of soil nutrient depletion holistically, thus decreasing the existing negative nutrient balances in the SSA region
Machine Learning Imagery Dataset for Maize Crop: A Case of Tanzania
Get PDFThis research article was published by Elsevier in 2023Maize is one of the most important staple food and cash crops that are largely produced by majority of smallholder farmers throughout the humid and sub-humid tropic of Africa. Despite its significance in the household food security and income, diseases, especially Maize Lethal Necrosis and Maize Streak, have been significantly affecting production of this crop. This paper offers a dataset of well curated images of maize crop for both healthy and diseased leaves captured using smartphone camera in Tanzania. The dataset is the largest publicly accessible dataset for maize leaves with a total of 18,148 images, which can be used to develop machine learning models for the early detection of diseases affecting maize. Moreover, the dataset can be used to support computer vision applications such as image segmentation, object detection and classification. The goal of generating this dataset is to assist the development of comprehensive tools that will help farmers in the diagnosis of diseases and the enhancement of maize yields thus eradicating the problem of fod security in Tanzania and other parts in Africa
Advancing the development and implementation of regional, national tuberculosis control programs in livestock in Africa, Asia, and Latin America
Get PDFThis research article was published by Frontiers in Veterinary Science in 2023Tuberculosis in livestock caused by members of the Mycobacterium tuberculosis (MTb) complex is a notifiable zoonotic animal disease (1), which has been eradicated or held to very low prevalence levels in many high-income economies. Successful campaigns were all build on a very strict test-and-slaughter strategy using the tuberculin PPD skin tests as diagnostic tool. However, tuberculosis in livestock remains endemic in most Low- and Middle-Income Countries (LMICs). This not only represents a threat to public health in those countries but also places a significant burden on their economies due to a negative impact on livestock productivity and the resources invested in healthcare, prevention, surveillance, and, when present, control and/or eradication programs. Moreover, tuberculosis in livestock affects a wide variety of species as well as breeds, raised in a wide variety of farming systems, in a broad range of different climates, thus ruling out a “one size fits all” approach for disease control. Since “traditional” test and cull programs are costly, very demanding on the livestock holder and may be ruled out as option for religious reasons, such programs must be tailored to ensure they are fit for purpose considering the respective socio-economic context in which they have to be implemented in each country
Better nitrogen fertilizer management improved Mchare banana productivity and profitability in northern highlands, Tanzania
Get PDFThis research article was published by MDPI in 2023Declining land productivity is a major problem constraining banana (Musa spp.) production
in Tanzania. Banana fruit yield consequently reaches only 15% of the potential, primarily due to
inadequate soil nutrient replenishment. Improving farmers’ soil nutrient replenishment strategy in
banana home gardens, which relies on applications of cattle manure only, by mixing with inorganic
fertilizer resources can increase land productivity and can improve the overall profitability of banana
production in the country. Experiments were conducted at Tarakea, Lyamungo, and Tengeru to
determine the effects of organic fertilizer resources (animal manure and crop residue) and their
combination with inorganic fertilizer resources on the productivity and profitability of Mchare
banana production. Banana fruit yield differed significantly among the experimental sites, with drier
areas of Tengeru recording, on average, 19.6 t ha−1 year−1
, while the more humid areas of Lyamungo
recorded, on average, 39.3 ha−1 year−1
. Mchare banana plants grown under sole inorganic fertilizer
produced significantly low yields (33.0 t ha−1 year−1
) compared with those fertilized with cattle
manure only, which lifted the yields to 38.8 t ha−1 year−1
, but the latter required more labor input.
Soil nitrogen (N) fertilization via cattle manure + mineral fertilizer gave the highest average banana
fruit yield (43.0 t ha−1 year−1
) across the sites, and reduced fertilization costs by 32%. Subsequently,
this integrated fertilization technique generated the highest average net benefits in all sites and both
cropping cycles. Thus, the findings of this study form a basis to improve land productivity and
profitability in banana-based home gardens in the study area by directing more labor input to good
soil N managemen