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Recent Submissions
Risk Factors Associated with Livestock Feeding and Disease Control Practices in the Peri-Urban Slums of Kisumu City, Kenya
(2020-07) Charles Muleke Inyagwa, Wekesa Sabesia, Kenneth Orengo, Price Amanya, and Raymond Mdachi
Livestock feeding practices present food safety concerns to consumers who are aware of food safety and their linkage to
feeding practices. Domesticated animals kept in the peri-urban territories often feed on waste dump feeds and polluted
waters. Consequently, animal feeds could be contaminated with potentially toxic metals and diseases which may lead to
death and economic losses in lost trade opportunities. Objective of this study was to determine the risk factors associated
with livestock feeding and disease control practices in the peri-urban slums of Kisumu City, Kenya. This was achieved
through identifying, characterizing and disseminating peri-urban livestock feeding practices and constraints, and their
effects on food safety as well as general well-being of livestock. Primary data was collected from 291 randomly selected
smallholder livestock farmers in the peri-urban slums of the City by use of semi-structured questionnaires. Descriptive
statistics inform of cross tabulations, means and frequencies were used to characterize peri-urban livestock feeding and
disease control practices. The results revealed that 58% of the county residents were male while 42 % were female. Their
ages ranged between 18 and 90years with a mean age of 55. Majority (74%) practiced both livestock and crop
production while 26% kept livestock only. The farmers mainly kept indigenous cattle (97%) as opposed to exotic (3%).
The prevalent livestock farming system was free range (93%) where most farmers grazed their livestock on open
unutilized spaces and dump sites. Animals were kept for consumption (62%) and for income generation (32%). The
main production constraints identified by farmers were diseases (65%) and lack of feed (20%). The diseases varied with
region and animal species which included tick-borne diseases (53%) and foot and mouth (15%). Farmers obtained
information on management and treatment of livestock largely from private veterinarians (64%). There is need to
create policies on peri-urban slum livestock keeping practices, and waste management to reduce the risks associated
with livestock feeding and diseases in Kisumu city.
Keywords: Food safety risks, peri-urban, livestock feeding, Kisumu County
Levels of heavy metals in the straightfin barb Enteromius paludinosus (Peters 1852) from River Malewa, Naivasha, Kenya
(Environ Monit Assess, 2018-11-12) Elizabeth A. Ngesa & Elick O. Otachi, Nzula K. Kitaka
There have been several studies on heavy
metals in Lake Naivasha. However, none of them has
reported the levels of mercury (Hg), arsenic (As), and
chromium (Cr). Moreover, there are no studies on the
heavy metals’ concentrations in the straightfin barb
(Enteromius paludinosus, Peters 1852), a fish species
that hosts a parasite (Ligula intestinalis), the latter hav
ing been reported to have a high ability to absorb heavy
metals from its host. This paper therefore addresses the
accumulation of heavy metals, namely arsenic (As),
chromium (Cr), lead (Pb), and mercury (Hg) in the
tissues of straightfin barb, Enteromius paludinosus (Pe
ters 1852) from the mouth of River Malewa in Lake
Naivasha, Kenya. A total of 1307 fish were collected
during the month of November 2017. Water samples,
sediment samples, 25 fish muscle tissues, and its endo
parasite, the cestode Ligula intestinalis,wereisolated,
and heavy metal concentrations were determined using
the thermal-electron atomic absorption spectrophotom
eter at the Lake Nakuru Water Quality Testing Labora
tory. The concentrations of heavy metals in the sediment
werebelowthelowesteffectlevel insediment, threshold
effect concentration in sediment, severe effect concen
tration in sediment, and the shale values of sedimentary
rocks thus showing no sign of pollution. In the muscle
tissues of the fish, As, Cr, Pb, and Hg showed high
levels with mean concentrations of 5.0696, 22.0854,
Bioconcentration factors further supported the observa
tion that trace element accumulation was higher in fish
compared with sediment and water. The target hazard
quotients of As, Cr, Pb, and Hg obtained for both the
female and male were >1 indicating a possible health
risk associated with the consumption of E. paludinosus.
The bioaccumulation factors (BAFs) for L. intestinalis
were 2.4093, 2.1873, 5.8601, and 5.1395 for As, Cr, Pb,
and Hg, respectively, indicating the potential of the
cestode in the accumulation of heavy metals from the
host; hence, it can be used as an accumulation
bioindicator.
Natural Infection of Sandfly Vector and Reservoir Hosts Species with Leishmania Parasites in Mt. Elgon Cave Habitats in Kenya
(International Journal of TROPICAL DISEASE & Health, 2023-02-15) Kennedy Ombula Ombaka, Moses M. Ngeiywa and Judith Makwali
Leishmaniasis is a major public health problem caused by a parasite of the genus Leishmania
which is transmitted through the bite of an infected female phlebotomine sandfly. However, the
disease epidemiology on interactions of causative agents, reservoir hosts,
and vectors in areas
where there is a high prevalence of the disease needs to be properly understood to inform effective
control. The present study was conducted to determine natural infection by Leishmania parasites in
phlebotomine sandfly vectors and suspected reservoir hosts found in caves in Mount Elgon in
Kenya. Sandflies, bats and rock hyraxes were found inhabiting the assessed caves in the study
area. A total of 5688 sandflies collected from caves were morphologically identified and analyzed
for infectivity with Leishmania parasites by molecular characterization sequencing using
Cytochrome c oxidase subunit 1 (COI). Giemsa-stained blood smears and spleen and liver
impression smears prepared from bats,
and hyraxes collected from the same caves were examined
microscopically for Leishmania amastigotes. The sandflies, bats,
and hyraxes were identified
morphologically using taxonomic keys. The results showed that randomly selected COI sequences
(n = 5) of three different morphologically identified Phlebotomus species were positive for
Leishmania based on their molecular characteristics. Five species of bats were identified,
and they
were significantly more abundant compared to hyraxes (χ2 = 16.7845, df = 7, P = 0.0002). The bats’
species had a higher prevalence of Leishmania parasites compared to hyraxes (F = 7.342, P =
0.0043). Cardioderma cor, Chaerephon pumilus and Rhinolophus clivosus bat species had more
than 5% Leishmania parasite prevalence rate. Leishmania amastigote density was significantly
higher in the liver (F = 39.232, P < 0.001) compared to the density in the blood (F = 75.1124, P <
0.001) of bats and hyraxes. This study has shown that transmission of Leishmania parasites in Mt.
Elgon caves involves vertebrate reservoir hosts (bats and hyraxes) and the insect vector species
(sandfly). Therefore,
disruption of the life cycle of the Leishmania parasites should be done by
targeting these reservoir animals and the sandfly vector.
Antimicrobial activity and cytotoxicity of selected medicinal plants found in Nandi County, Kenya
(A KeSoBAP Publication, 2015-08) Nicholas Kimutai a, Elizabeth W. Njenga, Pascaline Jeruto, Janet Kosgey, Jonah N. Kipkorir, Charles Mutai, Lillian Ng’eny, and Richard Korir
Background: Medicinal plants are widely used by the local people to treat various human diseases cause by drug
resistant microorganisms. For instance, Kigelia Africana fruits and barks are boiled in water and taken orally as a
laxative in treating stomach ailments, Ekebergia capensis bark is boiled in water and use for the control of gonorrhea
and tuberculosis while Fagaropsis angolensis stem bark is used to treat pneumonia, back ache and joins. The efficacy
and safety of most of these plants has not been determined.
Objective: The present study seeks to determine antimicrobial activities and cytotoxicity of the selected medicinal
plants indicated above, that are commonly used to treat infectious diseases.
Materials and Methods: Fresh plants were collected from the field; air dried ground and extracted using acetone and
water. The extracts were screened for antibacterial and antifungal activities using Staphylococcus aureus, Methicillin
resistant Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Shigella dysentriae, Candida albicans,
Cryptococcus neoformans, Microsporum gypseum and Trychophyton mentagrophytes. The methods were disc diffusion
and broth dilution methods while in vitro cytotoxicity test was carried out following a modified rapid calorimetric
assay, using actively dividing sub-confluent Vero E6 cells.
Results: In disc diffusion assay, water extracts of E. capensis were the most active (14.7 mm) while those of Fagaropsis
angolensis were the least (6.0 mm) against S. aureus. Acetone extracts of E. capensis and K. Africana had a Minimum
Inhibitory Concentration of 3.125 mg/ml and 6.25 mg/ml respectively and were bactericidal. Cytotoxicity showed
that K. africana was not cytotoxic against Vero cell lines while acetone extracts of E. capensis was moderately toxic
with a CC 50(µg/ml) of 12.5.
Conclusion: These results support the use of the plants in the traditional medicine as antimicrobials and they can be
exploited for novel drugs.
Key words: Antimicrobial activity, cytotoxicity, Kigelia africana, Ekebergia capensis, Fagaropsis angolensis,
ANTIBACTERIAL ACTIVITIES OF SELECTED MEDICINAL PLANTS FROM NANDI COUNTY, KENYA
(© Global Science Publications, 2020-08-13) NICHOLAS KIMUTAI K., PHILIP A. OGUTU AND CHARLES MUTAI
Medicinal plants are used by the local people to treat different human diseases since time
immemorial. The efficacy of most of these plants has not been determined. The present study was therefore
conducted at Nandi County to determine antimicrobial activities of seventeen selected medicinal plants that
are commonly used to treat infectious diseases caused by bacteria. The plants were collected from the field
and dried in a room at 25 oC. The samples were ground into powder and the components extracted using
methanol. Plant extracts were tested against ten standard and clinical isolates of human pathogenic bacteria,
using disc diffusion and broth dilution methods. The solvents used for extraction were used as negative
control while Gentamycin was used as positive controls. In vitro antimicrobial assays indicated that four
plant extracts exhibited antimicrobial activity in which the highest activity was observed from root bark
extracts of Albicia coriaria, Acacia lahai, Olinia rochetiana, Leucas calostachys and stem bark of Sygium cordatum
against S. aureus among others. This study demonstrated support for the claimed antimicrobial uses of the
plants in the traditional medicine probably due to the phytochemicals present. Isolation and purification of
bioactive chemical constituents from the active crude plant extracts can be obtained to supplement
conventional drugs