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Empowering agriculture: exploring warehouse receipt systems for financing producers in Tanzania
No full textDissertationThe Warehouse Receipt System (WRS) was initiated by the
government to enhance financing for cashew nut producers, ensure a
fair and stable market, and enable producers to store their yields in
warehouses for later sale at more favourable prices. However,
producers still express dissatisfaction with the system due to lack of
transparency. Moreover, the WRS is criticized for its complex lending
procedures and high interest rates when financing smallholder
producers, which deter producers from utilizing the system to borrow
money. Therefore, this study aimed to assess the effectiveness of
warehouse receipt systems for financing cashew nut producers in
Tandahimba District, Tanzania. Specifically, the study identified
smallholder producers’ perception and acceptance towards the
usefulness of WRS in accessing finance from financial institutions,
challenges facing smallholder producers in accessing finance from
financial institutions through WRS and the factors influencing cashew
nut smallholder producers to access finance from financial
institutions. A cross-sectional research design and a mixed methods
research approach were adopted. The study included 122
participants who included 100 smallholder cashew nut producers as
respondents, 8 WRS operator officers, 6 bank officers and 8
extension officers as key informants. Simple random sampling
technique was used to select smallholder cashew nut producers for a
household survey while purposive sampling technique was used to
identify WRS operator officers, bank officers and extension officers
for interview. Data were analysed using IBM SPSS to compute
descriptive statistics, particularly frequencies, percentages, means
and standard deviations. Moreover, binary logistic regression was
used to determine influence of WRS related factors on access to
finance from financial institutions. The findings show that smallholder
cashew nut producers had a negative perception and acceptance
towards the usefulness of WRS in accessing finance because WRS
neither assisted producers to access loans on time nor offered
collateral to producers to enable them access credits from financial
institutions. Likely, WRS did not assist producers in ensuring that
there were proper lending procedures to reduce risks to the financial
institutions. Also, it did not provide financial and credit information to
smallholder cashew nut producers. The challenges facing smallholder
producers in accessing finance timely included low investment in
financing cashew nut producers (92%), delayed loans (82%), lack of
enough understanding regarding loan process/provisions in financialinstitution 73(73%), producers being not sure of whether on a promise
of payment (68%), and lack of loan guarantee from WRS (64%).
Further, the factors influencing cashew nut smallholder producers to
access finance from financial institutions were age of the producers’
(ß = 1.421, p = 0.001), having financial statements for at least three
years of producers’ in cooperatives (ß = 1.249, p = 0.027),
membership to cooperative union (ß = 1.562, p = 0.014), absence of
criminal cases (ß = 0.931, p = 0.042), certificate of maximum liability
from registrar of cooperatives (ß = 2.556, p = 0.011), minutes of the
meeting which approved application for the loan from cooperatives (ß
= 1.257, p = 0.041), farm/ land size (ß = 0.824, p = 0.044) and
effectiveness of cooperative association in linking producers’ to
getting a loan from a financial institution (ß = 0.921, p = 0.032). The
findings suggest that producers who fulfilled the mentioned factors
were more likely to secure finance from financial institutions. These
factors contribute to building trust and credibility in the eyes of these
institutions. The findings also revealed that smallholder producers are
still facing significant challenges in accessing loans through the
Warehouse Receipt System (WRS). These challenges included
insufficient investment in financing cashew nut producers, delays in
loan disbursement, limited understanding of loan processes and
provisions among producers, uncertainty regarding the fulfilment of
promised payments, and the absence of loan guarantees from the
WRS. These difficulties resulted in a decline in both agricultural
production and marketing activities in the study area. The knowledge
generated from the study may assist the cashew nut board in
Tanzania through WRS to make a self-evaluation on how effective it
has been involving cashew nut producers to access finance through
their system; hence, take effective measures to lobby for
improvement and formulation of policies considering the factors,
challenges and perception and identified for efficient access to
finances among the cashew nut smallholder producers.Charles Mgenda and Mwanaisha
Ally Kitant
Assessment of genetic diversity of indigenous chicken ecotypes in selected areas of Tanzania
No full textDissertationIndigenous chickens are raised in a free-range and scavenging system.
However, an increased loss of diversity has been observed, and the
indigenous chicken genetic resources are considered to be the most
threatened due to the uncontrolled distribution of exotic breeds and
selective breeding by farmers. The purpose of this study was to assess
the diversity of indigenous chickens according to their phenotypic
characteristics based on their qualitative and quantitative characteristics
and genotype characteristics based on their allelic profiles in Bahi
Dodoma and Songea Ruvuma Tanzania for conservation purposes and
sustainable use. This was established by first determining the sample of
one hundred (100) chickens using a random sampling technique.
Phenotypic characteristics were then analyzed qualitatively and
quantitatively, and 1 ml of blood was drawn from the chicken wing vein
to assess genotypic characteristics using microsatellite markers. Data
from the qualitative and quantitative analysis were analyzed by using
Statistical Package for Social Sciences (SPSS) version 16.0 and Origin
Pro. Version 2019. P-value < 0.05 was used as a cut-off point for
statistical significance. GenAIEX v.6.5 software was used to analyze
genetic diversity parameters. For the case of phenotypic characteristics,
there is no significant difference in body weight and chest circumference
between the chicken from Bahi and Songea at p < 0.05, for the case of
body length, wingspan and shank length there is statistical significance
between Bahi and Songea chicken at p < 0.05. Shank colours were
associated with plumage colour, chickens with black plumage had black
shanks, while white plumage chickens exhibited the same pattern, and
single comb type was identified as the dominant one in this study for
62% Bahi and 88% Songea. Genetic diversity revealed that Bahi had a
total of 117 alleles while Songea had 111 alleles averaging 6.5 and 6.1
per locus for Bahi and Songea, respectively. The locus with the least
number of alleles was MCW0078, with just 5 alleles, whereas the MCW0111F locus was highly polymorphic with 20 alleles. The mean
number of different alleles (Na) was 7.250 ± 0.544 for Bahi and 7.000 ±
0.742 for Songea, with an overall average of 7.125 ± 0.515. The
number of private alleles was 31 and 37 for Bahi and Songea,
respectively. Genetic variation among the population was found to be
17%, while within the population, it was 83%. Nei’s genetic distance
was calculated to be 0.589, and the principle of coordinate analysis
revealed two clusters with some intermixes. This study showed a
significant phenotypic variation and relatedness between the two
chicken ecotypes, likely influenced by an individual’s genetic makeup
hence, they are very useful in conservation programs and sustainable
use of the indigenous chickens
Status and progress of forest landscape restoration of the Bunduki Gap in Uluguru nature forest reserve, Morogoro, Tanzania.
No full textDissertationForest Landscape restoration is a global imperative, addressing
ecological, social, and climate challenges. In Africa's drylands, FAO
identifies a critical need to restore 221 million hectares. In response,
African nations, including Tanzania, pledged through the African
Forest Landscape Restoration Initiative (AFR100) to restore 5.2
million hectares by 2030. However, the historical deforestation and
degradation caused by illegal logging, agriculture expansion, and fires
persist. In 2008, Tanzania government evict farmers from the Bunduki
gap to enhance biological connectivity within the Uluguru nature
forest reserve. Despite this, studies on the progress and composition
of land cover at Bunduki post-eviction are scarce. Such information is
crucial for justifying and supporting ongoing restoration initiatives
amid global demands for sustainable forest management and climate
change mitigation.
Therefore this study assesses pre and post-eviction land cover
changes at the Bunduki gap using high-resolution satellite images
(Quickbird 2005, Worldview 2011, Pleiades 2017). Employing
supervised image classification with a random forest algorithm on
Google Earth Engine, assesses classification accuracy, analyzes
changes in land cover classes, tracks their persistence and
trajectories, and examines spatial distribution for the periods 2005-
2011 and 2011-2017. Vegetation composition was evaluated in terms
of species richness, Important value index, diversity indices (Shannon
and Simpson’s), and hierarchical clustering, while structural
characteristics were analyzed in terms of diameter class distribution
across forest part.
The pre and post-eviction land cover assessment reveals dynamic
transformations in the study area between 2005, 2011, and 2017.
Forest coverage increased from 1.74% in 2005 to 51.80% in 2017,
while bushland, grassland, and bare land exhibited contrasting
trends. The main result is the replacement of bare land, grassland,
and bushland by forest land cover. The rate of this replacement
differs temporally and spatially across the gap. Vegetation composition analysis revealed 1,149 individuals representing 94
species, 47 families, and 89 genera. The majority of species (52.13%)
were common across all forest part, with the Bunduki Gap exhibiting
25.53% unique species. Three distinct communities were identified,
displaying significant differences (R=0.64, P<0.005), although no
significance difference was observed in diversity indices (P>0.005).
Diameter class distribution of the shared and unique species with
high importance value index varies significantly across forest part
(P < 0.0438), with higher diameter classes prevailing in Uluguru North
and South, and lower and medium classes more prevalent in the
Bunduki Gap, albeit with fewer instances in Uluguru North and South
respectively. The study concludes there is successful forest recovery
post eviction and there are similarities in emerged plant species
across the forest part with varying diameter distributions, the
presence of unique species and distinct communities underscores the
imperative for further investigation to mitigate the spread of invasive
species within the reserv
The impact of farmers research network project on diversified legumes among smallholder farmers in Singida region, Tanzania
No full textDissertationLegume production in Singida Region has been conducted for years but
with low yield production. The study aimed at assessing the impact of
Farmers Research Network on diversified legumes among smallholder
farmers in Singida Region. The study employed cross-section research
design with 204 respondents using questionnaire survey and key
informant interviews. A two-stage Heckman selection model was used to
determine factors influencing the adoption of diversified legume
production and farmers perception was assessed using Likert scale and
the analysis was then subjected to principal component analysis for
factor analysis. Descriptive and content analysis were conducted for
quantitative and qualitative data respectively employing Microsoft excel
for results presentation. The results on the factors influencing adoption
showed that age, education, farm size, major occupation, experience,
land size, access to credit, and motivation were significantly associated
with adoption of diversified legume production. The adoption of varied
legume production in the research area was found to be statistically
significantly influenced by the farmers' age, education level, farm size,
main occupation, experience, land size, availability to credit, and
motivation. Factors such as ease of cultivation, fair distribution of seeds,
food availability, increase in income level, high legume harvest, and
higher profitability of legumes (p < 0.05) significantly influenced
smallholder farmers' awareness and perception of diversified legumes.
Therefore, Farmers Research Network project has positively impacted
diversified legumes on smallholders farmers in Singida Region. There is
a need to increase training sessions to create awareness on diversified
legumes
Assessment of physical status of the irrigation structures in Nyarubogo irrigation scheme, Rwanda
No full textJournal articleThe physical status of irrigation structures holds immense importance in ensuring the efficient and sustainable management of water
resources for agricultural purposes. This study aimed to assess the physical status of the Nyarubogo irrigation scheme structures,
which has implications for the level of performance of this irrigation scheme. Specifically, the study assessed the effectiveness of the
irrigation infrastructures in terms of intake efficiency, canal physical condition, and command area development. Cross sectional
study design was employed, and units for the study were randomly selected to be included in this study. Observation method were
used to characterize the physical condition of the Nyarubogo irrigation scheme while questionnaire survey were used to collect data
on the implication of socioeconomic characteristics on the performance, and effectiveness of irrigation system. The collected data
were fitted to the irrigation structures assessment approaches suggested by Bos, Zende and Nagarajan. Analysis of farmer’s
responses was through Statistical Package for the Social Sciences (Version 27). This study evaluated the physical status of about
130 irrigation structures in Nyarubogo irrigation scheme. The structures included 7 division boxes, 73 water drops, 2 aqueducts,
42 turnouts, 4 bridges, and 2 Culverts. Overall, the scheme had an effectiveness of 63.8%, with culverts, bridges, and water drops
presenting more than the average functional condition of 64.38%, 75.00%, and 100.00%, respectively. The intake efficiency during
this study was found to be 67% accumulated from efficiencies of sediment level (20%), embankment (35%), and sluice gate (12%)
based on their weightage percentage and rank scores. The overall canal condition was good and was quantified to 70%. The
command area development was exhibiting subpar performance, registering a mere 32% effectiveness. Moreover, the study
evaluated how farmers' socio-economic status influenced the inadequate maintenance of the Nyarubogo irrigation systems. It
uncovered numerous elements contributing to this dilemma: there was limited engagement of women and youth in agricultural
pursuits, low educational attainment, challenges surrounding land ownership (specifically, land tenure), the small size of land
holdings per household and a notable absence of government incentives for maintenance efforts. These factors, however, when
coupled with inadequate funds derived from water fees, significantly obstruct the proper care of these irrigation infrastructures. On
the other hand, high runoff due to heavy rainfall was mentioned by the majority of farmers (20.7%) among the primary causes of
poor maintenance of irrigation structures. Generally, the evaluation of the Nyarubogo irrigation system structures emphasizes the
uneven levels of efficacy and challenges, highlighting the necessity of focused maintenance efforts and enhanced water management
techniques.Ministry of Agriculture in Tanzani
Contribution of systematic land formalization in women’s land ownership: a case of Ifakara Town Council, Tanzania
No full textMA. DissertationLand is important as one of the production inputs and investments.
Official land ownership provides opportunities for the owners to
utilize it for economic development purposes. Women often belong
to the disadvantageous group in land ownership due to different
factors including inheritance related aspects. Access to and
ownership of land officially contributes to reducing discrimination.
Understanding the benefits derived from official land ownership and
factors impeding women's access and ownership to land is crucial
for policymakers and law implementers. Land ownership in this
study is described as the rights an individual is given by the
government after acquiring land through inheritance, purchase or
customary tenure arrangement. The state provides the right to
transfer, sell, and use the land for investment or production without
interference. The government of Tanzania implemented the pilot
Land Tenure Support Programme (LTSP) from year 2016 to 2019,
which applied a systematic land formalization approach in Ifakara
Town Council in the Morogoro region. This study assessed the
contribution of a systematic land formalization approach to women‘s
land ownership in rural areas of Tanzania. Specific objectives of this
study were to assess the influence of socio-cultural factors on
women‘s right to land ownership and to determine the benefits of the
systematic land formalization approach on women's land ownership
in Ifakara Town Council.
The study area was selected based on the presence of beneficiary
landholders in the programme, that is, those who possessed
Certificates of Customary Right of Occupancy (CCROs). The
CCROs were acquired through the Land Tenure Support
Programme (LTSP) implemented in the area using a systematic land
formalization approach. The programme aimed at providing a road
map for accountability for land governance and effective land
administration systems. The systems were expected to contribute to
securing legitimate tenure rights in favour of rural poor, women, and
vulnerable groups that would result in increasing incomes and contribute to job creation. This area where LTSP was implemented
comprises people from different ethnic groups with different social
and cultural norms and values, which often hinder women‘s rights
from owning land. The approach as authored by De Soto (2000) and
which originated from the comprehensive tenure reform of land and
the evolutionary theory of land rights (ETLR) (Platteau, 1996) was
used to guide the study. The theory and approach assume that there
are benefits and obstacles resulting from the application of land
formalization approach.. The study employed a mixed-methods
approach that combines quantitative and qualitative research
methods for a better understanding of the contribution of the
systematic land formalization approach to women‘s land ownership.
A cross-sectional research design was applied for data collection
from sampled households at a single point in time in the Land
Tenure Support Programme implemented area. A multistage
sampling technique was applied in this study. Three of the nineteen
wards were selected purposely from the programme implementation
area, followed by a simple random selection of six villages among 28
villages. A sample of 120 households was determined by using
Krejcie and Morgan's formula. A simple random sampling technique
was applied in the selection of 120 participants from the list of
landholders who possessed CCROs.
The study used a structured questionnaire administered to 120
households for collecting quantitative data and a checklist of
questions for collecting qualitative data from 8 Focus Group
Discussions (FGD) and 9 Key informant interviews (KIIs). The
participants for FGDs and KIIs interviews were selected based on
their capacity to offer relevant information on how systematic land
formalization contributes to women's official land ownership. The
qualitative and quantitative data were tracked through designed
tools and predetermined periodic checks whereby information and
communication technologies (ICT) were used in data collection
through the use of the Open Data Kit (ODK). Quantitative data were analysed using IBM SPSS Statistics 24
software and in this case, descriptive and inferential statistics were
computed. The descriptive statistics entailed frequencies,
percentages, mean, and standard deviations. Content analysis
(conceptual and relational) was used for analysing qualitative data.
The analysis determined the effect of systematic land formalization
based on the views of the respondents on women‘s right to land
ownership, socio-cultural roles, and practices related to it, including
socio-cultural status attached to women‘s land ownership.
A non-parametric test (Mann-Whitney) was applied to assess the
association between opinions and socio-cultural factors that
contribute to women‘s right to land ownership, and to test the
hypothesis about the role of socio-cultural factors and the difference
that exists between males and females.
According to disaggregated data from the programme report (LTSP),
about 29 per cent of women as individuals managed to acquire
CCROs as an achievement; 65 per cent for men as individuals, 56
per cent for co-ownership with women.
The findings showed that 67.8 per cent of women respondents were
married to single woman orientation meaning one woman to one
man, and the majority of them (51%) owned land officially. Polygamy
marriage, which accounted for 30.5 per cent influenced women's
land ownership mostly in a negative way. The results showed further
that 28.8 per cent of females married at child age of between 14 and
17 years, according to the Marriage Act of 1971 of the Laws of the
Republic of Tanzania. As for the education level, the findings
indicated that 60 per cent of women with higher education could
access, control, transfer land and use it for investment, and there
was a statistically significant difference between females with high
education and those with lower education. The findings further showed a statistically significant difference
(p<0.05) between males‘ and females‘ mean rankings for socio-
cultural factors namely property ownership, polygamy, the
reproductive role of women, men‘s supremacy, and migration of
men, that influence women‘s rights to land ownership. Women who
owned land officially had their social assets increased, and the
majority (78.8%) gained acceptance in their community and
increased their decision-making power in the community.
The findings also indicated the higher mean rank of above 59.00 on
the economic use of land certificate as the right to rent out, sell, and
use the land as collateral and for business. Also, findings showed a
statistically significant difference in ranking between those with and
without land certificates (CCROs) in the same economic benefits
(p<0.05). The results indicate that there were social benefits derived
from land certificates ownership such as the reduction of domestic
violence at the household level, and income generation using land
for agricultural production and livestock keeping. The findings
revealed that about 114 per cent of the respondents' landholders
agreed that CCROs can be used to access loans from financial
institutions. The findings indicated that 14.3 per cent of the
respondents managed to access the loan by using CCROs worth
TZS 500 000 to 8 000 000.
There was a statistically significant difference in ranking those with
and without land certificates (CCROs) in terms of social benefits for
violence reduction and holding land for the future (p<0.05). The
findings indicated a statistically significant difference between
women, with those possessing land certificates having more
chances to participate in land management, marketing of the
produces, and attending training and workshops than those with no
certificates (P<0.05).
The land is a vital input to economic development in many settings.
Official land ownership is important to the poor and disadvantaged groups including women. In many societies, land ownership follows
socio-cultural values and norms, which discriminate against females
and favour males. The findings showed that socio-cultural factors
contribute to some extent to limiting women from participating in the
systematic land formalization approach, which offers them
Certificates of Customary Right of Occupancy (CCROs). Women‘s
low education level was also one of the factors that hindered women
from owning land officially. The study found that the systematic land
formalization approach has brought about some benefits among
women from their use of CCROs. From CCROS, women gained
security, and the land became an asset, which brought about social
and economic benefits. Through owning land certificates, women
are recognized in the community and involved in community
governance as well as decision-making.
The study recommends that the local government of Tanzania
should promote a gender-responsive land tenure system through
locally made bylaws to scale up the land formalization approach
countrywide to benefit the majority of women. Such promotion will
increase the number of women who will legally own land by reducing
or removing the socio-cultural and economic barriers to women
associated with their deprivation of land ownership
Organophosphorus pesticide residues in tomatoes: a case of Mlali and Doma Wards in Mvomero District, Morogoro
No full textExtensive pesticide use poses a significant challenge to Tanzania's horticulture industry, particularly affecting the leading tomato producer, the Morogoro region. This study focused on assessing organophosphorus pesticide residues in tomatoes from Mlali and Doma divisions in the Mvomero district of Morogoro. A total of 40 samples were collected from both farms and markets for analysis, utilizing Gas Chromatography with Mass Spectrometry (GC-MS) for extract analysis. Statistical Analysis Software (SAS) Version 9.1 was employed for data analysis. The study identified six organophosphorus pesticides, with concentrations in the following order: pirimiphos methyl > diazinon > fenitrothion > dimethoate > profenofos > chlorpyrifos. Pirimiphos methyl levels ranged from 3.32±0.03 to 9.53±0.05 μg/kg in Mlali samples and 0.20±0.01 to 6.33±0.03 μg/kg in Doma samples. Chlorpyrifos was detected in the lowest concentrations across all samples. Interestingly, higher pesticide levels were found in market samples compared to those from farms, suggesting potential misuse post-harvest and during distribution. This misuse could have severe consequences for tomato consumers, including both carcinogenic and non-carcinogenic effects. The study underscores the importance of educating farmers on the proper use of pesticides and the potential adverse effects resulting from their misuse. Addressing this issue is crucial for ensuring the safety of tomatoes in the market and protecting consumers from harmful effects associated with pesticide residues
Health and ecological risk assessment of heavy metals in water and sediments within a data scarce urban catchment in Tanzania – A case of Ngerengere River, Morogoro Municipality
No full textResearch Article, PP. 72-87Low-, middle- and high-income countries, exhibit indications of risks associated with water
quality. The study investigated heavy metal concentrations in surface water and sediments
within the Urban catchment of the Ngerengere River in the Morogoro Municipality of
Tanzania, an Urban Catchment Area (UCA) with limited available data mainly because of
inadequate monitoring and reporting capabilities. Analysis of health and ecological risks
associated with heavy metal pollution was also carried out using health risk assessments
models, pollution indices, and multivariate analysis techniques. Between the dry and wet
seasons of 2023, water and sediment samples from (13) sampling stations strategically
established along the Ngerengere river and its tributaries were analyzed for six heavy
metals (Pb, Cr, Ni, Cd, Cu and Zn) using the Atomic Absorption Spectrophotometer Model
Perking Elmer 850 Graphite Furnace and Perking Elmer AS 800 Auto-sampler coupled
with a computer interface for operational, displaying and reading the results. The calculated
degree of water contamination (Cd) values in river water in both dry and wet seasons ranged
from 0 to 6.803 indicating low and high degrees of contamination respectively. Heavy
metal concentration in sediment decreases in the order of Zn>Ni>Cr>Cu>Cd>Pb. The non-
cancer risk index (HI) via ingestion and dermal pathways in dry and wet seasons for both
children and adult groups was <1 hence no non-cancer risk, However, cumulative dermal
and ingestion exposure in both children and adults indicated potential cancer risk in dry
and wet season. The analysis of ecological risks associated with heavy metal enrichment in
the sediment indicated high enrichment of sediments with Cd, Ni and Zn. Conclusively, in
wet months, risk indices tend to be low, while in dry months, they typically remain highSokoine University of
Agriculture through its capacity-building program for staff
Assessing the perceptions of teachers and students on the integration of technology- enhanced teaching and learning in Secondary Schools in Dodoma City
No full textInternational
Journal for
Multidisciplinary
Research (IJFMR)The increase in demand for technology usage has influenced many sectors, including education. However,
teachers’ and students’ perceptions have a great impact on the effectiveness of technology-enhanced
teaching and learning. Therefore, the purpose of this study was to assess teachers’ and students’
perceptions of the use of technology-enhanced teaching and learning and find out if there was an
association between teachers’ and students’ demographic characteristics and their perceptions of
technology use in teaching and learning. A cross-sectional design was used to gather information from the
field. Secondary school teachers and students in Dodoma City constituted the study population. 83
teachers and 393 students from 10 secondary schools were selected purposefully. The self-administered
questionnaire was used to gather data from both categories (teachers and students). The data was analyzed
by using percentages and statistical tests, including Chi-square goodness of fit and one-way ANOVA, to
determine the association and relationship between teachers’ and students’ perceptions in relation to the
selected demographic characteristics. The study found that teachers and students have positive perceptions
of the use of technology in teaching and learning in public secondary schools. Furthermore, it was found
that the education level of teachers, the class of students, and the age of teachers influenced the perceptions
of the use of technology in teaching and learning. The study recommended that the government should
ensure pieces of training for teachers, motivation, and a conducive environment for the use of technology
in teaching and learning in secondary schools
Assessment of potential factors for plague transmission in the plague endemic area of Karatu District, Northern Tanzania
No full textMSc DissertationBackground: Plague, caused by Yersinia pestis, is a severe
zoonotic disease with rodents and fleas as primary hosts and
vectors. Despite being quiescent in several foci in Tanzania, plague
remains a significant public health concern due to its recurring
nature. The Karatu district experienced plague outbreaks in 1996
and 1997. Subsequent studies have reported evidence of Yersinia
pestis DNA in rodents in this endemic area in 2006 and 2013.
Consistent surveillance of the plague pathogen in rodent
communities and monitoring rodents and flea abundance is crucial
to assess the risk of human plague outbreak and the health of the
rodent populations in the vicinity of human habitats. This study
aimed to assess potential attributes for plague transmission in
Karatu district during the periods of disease quiescence. This study
was conducted in Karatu district in January and February, 2022 (wet
season) and repeated in July 2022 (dry season) The study aimed to
enhance surveillance of plague in plague foci and adjacent non-
plague foci - villages to determine the prevalence of plague bacilli in
the rodents, and identify the need for enhancing control measures.
This work is at the nexus of the One Health approach, as it involves
the surveillance of the plague zoonotic pathogen in the small
mammals for the purpose of enhancing public health. The results of
this study will be useful in informing public health, vector control, and
environmental institutions about the potential factors that may
underlie the transmission of the plague agent, Y. pestis, in the
plague-endemic area of Karatu district, northern Tanzania.
Methods: A repeated cross-sectional study was conducted in four
selected villages of Karatu district, involving two plague foci villages
and two non-plague foci villages, during the wet and dry seasons. A
total of 120 Sherman traps were used to capture rodents in farm
land habitats, peridomestic areas, bush lands, and forest buffer
zones, with an approximate distance of 300 to 500m between
habitats. The captured rodents were anaesthetised and identified using a dichotomous key after taking various morphological
measurements. Blood samples were collected from the
anaesthetised rodents through the supraorbital vein using glass
micro capillary tubes. Ectoparasites (fleas) and internal organs
(lungs and spleen) were collected and preserved in 70% ethanol and
absolute ethanol, respectively. Fleas were processed in the
laboratory and identified to genus and species levels using the
available dichotomous key. Blood smears were prepared on
microscope glass slides and preserved in slide boxes at room
temperature. In the laboratory, the blood smears were stained with
Wright-Giemsa stain and observed for the presence of Y. pestis
coccobacilli under a compound light microscope at ×1000
magnification. The presence of bipolar-stained coccobacilli bacteria
triggered suspicion for Y. pestis. The microscopy results were then
confirmed using qPCR to detect the presence of the pla gene of Y.
pestis DNA, extracted from the rodent lungs and spleens.
Results: A total of 291 rodents belonging to nine species were
captured in peridomestic areas, farmlands, bushes, and forest buffer
zones. Mastomys natalensis was the most abundant species
(41.92%), followed by Arvicanthis niloticus (24.05%), Lemniscomys
striatus (14.78%), Rattus rattus (8.59%), Lophuromys flavopunctatus
(4.47%), Grammomys spp (4.12%), Otomys spp (1.03%),
Graphiurus murinus (0.69%), and Praomys delectorum (0.34%).
Rodent abundance varied significantly among species and across
seasons however, was not statistically significant different between
plague and non-plague foci villages or across habitats. The rodent
diversity, expressed as Shannon-Wiener diversity index, was slightly
higher in plague foci villages compared to non-plague foci villages
(0.7 and 0.6, respectively). Peridomestic areas had the highest
diversity index (0.92), followed by farmlands (0.65), bush lands
(0.64), and forest buffer zones (0.00). Out of the 291 rodent blood
smears examined, 34 were suspected positive for Y. pestis
coccobacilli, with one sample from M. natalensis confirmed positive
for the plasminogen activator (pla) gene of Y. pestis DNA by qPCR. The findings further indicated that 190 fleas belonging to four
different species were collected from 73 rodents, belonging to six
species. Among the collected fleas, Dinopsyllus lypusus was the
most abundant (46.32%), followed by Ctenophthalmus spp
(26.84%), Xenopsylla brasiliensis (16.32%), and Xenopsylla cheopis
(10.53%). A total of 38.42% fleas were collected from M. natalensis,
22.63% from L. striatus, and 18.42% from R. rattus. The highest flea
infestation prevalence was found on R. rattus with preponderance of
X. cheopis and X. brasiliensis. The specific flea index of X. cheopis
on R. rattus was (1.0 SFI) in plague foci and (<0.5 SFI) in non-
plague foci villages. The result of the GLM final model indicated that
the flea abundance on rodents was significantly dependent on
rodent species, season, habitats, rodent weight, sex, and location.
There was a weak positive correlation between rodent weight and
flea abundance.
Conclusion: Overall, the study suggests a possible enzootic
circulation of Y. pestis in sylvatic rodents in the plague foci villages
of Karatu district. The high abundance of rodents and fleas,
particularly in farmlands and peridomestic areas, increases the
potential risk for the transmission of the plague pathogen to the
surrounding population and thus poses a threat to public health,
especially considering that these habitats serve as crucial sites for
human economic activities, interactions, and livelihoods. Therefore,
it is of paramount importance to maintain vigilant rodent control to
mitigate any risks of repeated plague outbreaks.Africa Centre of Excellence for Innovative Rodent Pest Management and Biosensor Technology and
Development (ACE IRPM&BTD