23 research outputs found

    Microbiological quality and safety of raw and pasteurized milk marketed in and around Nairobi Region

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    The microbiological quality of raw and pasteurized milk marketed in Nairobi and its environs was determined. Milk samples were collected randomly at milk selling points from three market areas: rural (Kiambu/Ngong), urban (East/West of Tom Mboya street) and slum (Kibera/Mathare). Samples were analysed for titratable acidity, total viable count (TVC), Staphylococcus aureus, coliforms and Enterobacteriaceae. Titratable acidity was determined using titration method, while TVC, S. aureus and Enterobacteriaceae were determined by the spread plate methods and coliforms were determined by most probable number. Data collected were subjected to analysis of variance using Genstat statistical package. The mean acidity was 0.20% lactic acid (LA), while mean counts for TVC, S. aureus, coliforms and Enterobacteriaceae were 6.05, 3.46, 2.30, and 3.93 log10cfu/ml, respectively. The  ercentage of milk samples with acidity values greater than 0.18% LA, the upper limit set by Kenya Bureau of Standards (KEBS), was 52.8 %. Total viable count (TVC) greater than 106 cfu/ml, was detected in 95.2% and 21.4% of raw and pasteurized milk, respectively. Coliform counts greater than 4.70 and 1.0 log10cfu/ml for raw and pasteurized milk were detected in 77.8% and 4.8%, respectively of raw and pasteurized milk samples collected. Enterobacteriaceae and S. aureus were detected with mean counts ranging from 6.08-6.86 and 5.82-6.32 log10/ml, respectively. Highest mean acidity and counts were recorded from slum areas of Nairobi and there were significant differences between raw and pasteurized milk (P<0.05). The poor bacterial quality coupled with high acidity of raw milk, indicates poor hygienic practices and lack of temperature control during marketing. The incidence of high acidity and bacterial counts in pasteurized milk could indicate post process contamination and/or inappropriate storage of the milk. Most vendors of pasteurized milk were observed selling directly from the distributor crates without refrigerated storage. The rapid deterioration of raw and pasteurized milk marketed in Nairobi, at the time of this study, may be largely due to poor hygienic standards and non-adherence to temperature controls during handling, distribution and marketing. This requires urgent attention by the appropriate authorities, because the poor microbiological quality of raw milk and pasteurized milk may expose consumers to health risks associated with the consumption of contaminated milk.Key words: Marketed milk, quality, acidity, total viable count, coliforms, enterobacteriaceae, Staphylococcus aureu

    Benthic community structure and ecosystem functions in above- and below-waterfall pools in Borneo

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    Waterfalls are geomorphic features that often partition streams into discrete zones. Our study examined aquatic communities, litter decomposition and periphyton growth rates for above- and below-waterfall pools in Ulu Temburong National Park, Brunei. We observed higher fish densities in below-waterfall pools (0.24 fish m−2 vs. 0.02 fish m−2 in above-waterfall pools) and higher shrimp abundance in above-waterfall pools (eight shrimp/pool vs. less than one shrimp/pool in below-waterfall pools). However, macroinvertebrate densities (excluding shrimp) were similar among both pool types. Ambient periphyton was higher in below-waterfall pools in 2013 (4.3 vs. 2.8 g m−2 in above-waterfall pools) and 2014 (4.8 vs. 3.4 g m−2 in above-waterfall pools), while periphyton growth rates varied from 0.05 to 0.26 g m−2 days−1 and were significantly higher in below-waterfall pools in 2014. Leaf litter decomposition rates (0.001 to 0.024 days−1) did not differ between pool types, suggesting that neither shrimp nor fish densities had consistent impacts on this ecosystem function. Regardless, this research demonstrates the varied effects of biotic and abiotic factors on community structure and ecosystem function. Our results have highlighted the importance of discontinuities, such as waterfalls, in tropical streams.</p

    Clinical Ethics in Gabon: The Spectrum of Clinical Ethical Issues Based on Findings from In-Depth Interviews at Three Public Hospitals

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    Introduction Unlike issues in biomedical research ethics, ethical challenges arising in daily clinical care in Sub-Saharan African countries have not yet been studied in a systematic manner. However this has to be seen as a distinct entity as we argue in this paper. Our aim was to give an overview of the spectrum of clinical ethical issues and to understand what influences clinical ethics in the Sub-Saharan country of Gabon. Materials and Methods In-depth interviews with 18 health care professionals were conducted at three hospital sites in Gabon. Interview transcripts were analyzed using a grounded theory approach (open and axial coding),giving a qualitative spectrum of categories for clinical ethical issues. Validity was checked at a meeting with study participants and other health care experts in Gabon after analysis of the data. Results Twelve main categories (with 28 further-specified subcategories) for clinical ethical issues were identified and grouped under three core categories: A) micro level: "confidentiality and information","interpersonal, relational and behavioral issues","psychological strain of individuals",and "scarce resources";B) meso level: "structural issues of medical institutions","issues with private clinics","challenges connected to the family",and "issues of education, training and competence";and C) macro level: "influence of society, culture, religion and superstition","applicability of western medicine","structural issues on the political level",and "legal issues". Discussion Interviewees reported a broad spectrum of clinical ethical issues that go beyond challenges related to scarce financial and human resources. Specific socio-cultural, historical and educational backgrounds also played an important role. In fact these influences are central to an understanding of clinical ethics in the studied local context. Further research in the region is necessary to put our study into perspective. As many participants reported a lack of awareness of ethical issues amongst other health care professionals in daily clinical practice, we suggest that international organizations and national medical schools should consider infrastructure and tools to improve context-sensitive capacity building in clinical ethics for Sub-Saharan African countries like Gabon

    Impacts of benthic coarse particulate organic matter variations on macroinvertebrate density and diversity in the Njoro river, a Kenyan highland stream

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    An investigation to assess the relationship between coarse particulate organic matter (CPOM) and macroinvertebrate communities was undertaken in the Njoro River, Kenya during 2010. Significantly lower macroinvertebrate densities and diversities were observed in study sites with low Coarse Particulate Organic Matter (CPOM) content. The Mugo study site had the highest CPOM content and macroinvertebrate density and diversity. The unidentifiable detritus category (i.e. small CPOM fragments) had the highest influence on macroinvertebrate taxa whereas twigs had the least influence. The benthic samples were dominated by detritivores, but no shredders were recorded. Our results suggest that CPOM is an important determinant of the macroinvertebrate assemblages in streams. Given this, we believe that it is important to conserve tropical stream riparian vegetation due to their important role as a source of CPOM in streams.Keywords: Benthic organic matter, Kenya, riparian vegetation, macroinvertebrate

    Effect of sieve mesh size on the estimation of benthic invertebrate abundance and composition in the Honi river, Kenya

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    Characterisation of benthic invertebrate communities, taxonomic abundance and composition provides information that is used during river bioassessment. However, the mesh size of the sieves used during processing of invertebrate samples may affect the estimation of taxonomic abundance and composition. In the current study, the effect of sieve mesh size (&gt;0.5 and &lt;0.5 mm) on the estimation of invertebrate taxonomic abundance and composition was tested in the Honi River (Kenya) in 2011. The abundance of invertebrates retained by the &gt;0.5 mm mesh sieve was significantly (p &lt;0.05) lower than that found in the total sample. At the Honi River midstream site, most invertebrates (85%) belonged to the &lt;0.5 mm fraction and were dominated by chironomids. Hydracarina and ostracods were only found in the &lt;0.5 mm fraction of invertebrates. This study shows that sieve mesh size should be taken into consideration when characterising benthic invertebrates in rivers where invertebrate taxa are unknown and with high abundances of small sized invertebrates.Keywords: benthic invertebrates; sieve mesh size; river; Keny

    Effect of drift sampler exposure time and net mesh size on invertebrate drift density in the Njoro River, Kenya

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    <p>Although invertebrate drift is an important ecological process in lotic ecosystems, very little is known about it in Kenyan rivers. The primary aim of this study was to investigate the effect of driftnet mesh size and exposure duration on drift density in 2017. Drift samples were dominated by Chironomidae, Baetidae, Simuliidae, Caenidae and Culicidae. The 100 µm mesh driftnet had the highest mean invertebrate density, followed by the 250 µm and 500 µm nets. Invertebrate drift densities decreased with increased exposure time. This study demonstrates that sampler mesh size and exposure time should be taken into account when characterising invertebrate drift in streams. Future studies should consider sampling different biotopes and during different seasons.</p

    Phytochemical studies on herbal plants commonly used for processing and preserving meat and milk

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    Objective: The study aims at identifying and collecting herbal plants commonly used in milk processing and preservation by the Maasai community in Kajiado district and to determine the phytochemical and mineral composition.Methodology and Results: Twenty-three herbal plants were identified; three plants were selected through community prioritization using a structured questionnaire. Analysis for phytochemical composition was done using Sofowara (1993), Trease and Evans (1989) and Harborne (1998) methods composition by AOAC method 923.03 (AOAC, 1995) and pH. Tannins, saponins, flavonoids, alkaloids, steroids, sterols, terpenoids, flavones aglycones and reducing compounds were present in all the herbal plants. The herbal plants were significantly different (P&lt;0.05) in mineral content. The highest mineral content was calcium 90.0 mg/100 g followed by magnesium, zinc and iron.Conclusion and application of the findings: this indicates that these plants are rich in phytochemicals and minerals therefore, they can be exploited to develop nutritive food preservatives because phytochemicals have both antimicrobial and antioxidant properties. These plants can also be processed to obtain a product that will substitute the chemical preservatives in the market now that consumers are showing greater preference for products preserved with natural products.Keywords: phytochemicals, herbs, minerals, antimicrobia
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