Department of Pharmacology and Toxicology

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Accessibility and use of information and communication tools among farmers for improving chicken production in Morogoro municipality, Tanzania
(Livestock Research for Rural Development, 2016) Temba, B. A.; Kajuna, F. K.; Pango, G. S.; Benard, R
Obtaining correct and appropriate extension services is an important aspect of maximizing production among farmers. This is a cross sectional study carried out to assess the use of information and communication tools (ICTs) to get extension services among chicken farmers and identifying factors hindering the accessibility and use. The study was conducted using structured questionnaire involving 160 chicken keepers randomly chosen from list of poultry keepers and voluntarily concerted to participate in four wards of Morogoro municipality. Data collected were analyzed for descriptive statistics, comparisons and correlations. It was identified that majority of farmers used televisions, mobile phones and radio to get extension information while few farmers occasionally use internet, magazines, books, fliers and audio-visual materials like DVDs. 82.5% of the farmers do not get enough information they needed for their projects. High costs, unreliable electricity, poor TV and radio signals and lack of knowledge on the use or modern tools were pointed as major limiting factors. It was however observed that the use of information and communication tools to access extension services strongly correlated with productivity of chicken enterprises. We therefore recommend for more efforts to facilitate and sensitize farmers on the better use of ICTs for their enterprises.
Antimicrobial activity of indigenous plants used by pastoral communities for milk preservation in Kilosa District, Tanzania
(Sokoine University of Agriculture, 2017) Kawanga, C. N.
Milk is an important part of the diet among pastoral communities in Kilosa district, Tanzania. Its production and consumption derives much food security and economic benefits to the rural people in the district. However, Milk has a complex biochemical composition and its high-water activity and nutritional value serves as an excellent medium for growth and multiplication of many kinds of microorganisms. This shortens the shelf-life of milk. In the framework of research to improve the shelf-life and safety of milk, this study was conducted to explore the indigenous knowledge on milk preservation and antimicrobial activity of the commonly used plants in milk preservation. A survey was conducted on the use of herbs in milk in Parakuyo and Mbwade villages in the district, after which leaves, stems and roots of two plant species of Dalbergia melanoxylon and Combretum imberbe were collected for laboratory analysis. Biological activity using minimum inhibitory concentration (MIC) serial dilution assay against six milk spoilage bacteria and titratable acidity were determined. The common methods for preservation of milk were boiling, fumigation of milk containers using dried stems and roots of selected plant species and fermentation. Ethanol extracts of the plant parts showed antimicrobial activity against Escherichia coli, Salmonella typhi, Pseudomonas aeriginosa, Staphylococcus aureus, Streptococcus agalactiae and Proteus spp. Stem extract of D. melanoxylon showed highest activity with an MIC of 3.125 mg/ml. The difference in biological activity among the extracts was not statistically significant. Furthermore, there was no statistical difference in lactic acid production between milk samples treated with extracts and non-treated fresh milk samples. The results of this study give credence to the traditional use of Dalbergia melanoxylon and Combretum imberbe and expand our knowledge on the biological activity of their extracts as potential natural preservatives.
Assessment of antimicrobial activity of velvet bush willow (Combretum molle) crude bark extracts on selected bacteria species
(2021-10) Mgonja, Frida Richard; Ally, Mohamed Hamed Sango
Treatment and control of infectious diseases in humans and animals play a vital role in prevention of illness and death. Conventional drugs treatment has been providing effective therapy for treatment of infections caused by pathogenic microorganisms; However, some do not respond to conventional therapy. Conventional therapy are expensive and have more adverse side effects. Plant based medicinal productshas been used as an alternative curative for infections caused by resistant pathogenic microorganisms, moreover, plant medicinal products have less adverse side effects. This study was conducted to assess thecrude Combretummolle bark extracts antimicrobial activityagainst three selected bacteria species. Three solvents, distilled water; ethanol and acetone were used for crude combretum molle bark extraction. The agar well diffusion method was used to assess antimicrobial activity against Streptococcus pyogenes, Pseudomonas aeruginosa and Escherichia coli. A minimum inhibition concentration (MIC) of the most active extracts was determined by the broth dilution technique. Extracts from three solvents tested demonstrated antimicrobial activity with zone of inhibition diameters ranging from 14 to 24 mm. Acetone extract was the most potent with its minimum inhibitory concentration (MIC) ranging from 1.25 to 2.50 mg/ml. There was no statistically significant difference (P>0.05) in the potency of the three extracts and standard antibiotic ciprofloxacin on the bacteria species tested. The study showed that the crude bark extract of C. molle has antimicrobial activity against all the test microorganisms.
Bacteriological Quality of Tilapia Fish from Treated Wastewater in Peri-Urban Areas, Morogoro, Tanzania
(Science Publishing Group, 2016-10) Mhongole, Ofred Jonas; Mdegela, Robinson Hammerthon; Kusiluka, Lughano Jeromey Moses; Dalsgaard, Anders
The aim of this study was to assess faecal bacterial contamination in tilapia fish from wastewater treatment ponds at Mzumbe and in pristine water in Mindu dam. Tilapia fish (fish flesh and fish intestines) and water samples were analysed for Escherichia coli and total plate count. The concentration of E. coli in fish intestines ranged from about 1 - 3.5 log cfu/g and <1 log cfu/g in fish flesh. Total plate count ranged from 1 – 3 log cfu/g in fish flesh and 2 – 6 log cfu/g in fish intestines. The concentration of E. coli in pristine water in Mindu dam ranged from 0 to 15 cfu/mL. From the inlet to outlet of Mzumbe wastewater treatment pond, there was a significant reduction (p<0.05) of E. coli concentration along the gradient from 2.05 to 0.55 log cfu/mL, respectively. These findings demonstrated that tilapia fish from the two study sites were of good quality for human consumption based on microbial faecal contamination. On the other hand treated wastewater of the quality found in this study may be used for aquaculture. However, continuous monitoring for bacteriological quality and safety parameters including E. coli and total plate count is required.
Biological activity of extracts from commiphora swynnertonii against microbes of veterinary importance in chickens
(Sokoine University of Agriculture, 2013) Bakari, Gaymary G.
Studies were carried out to establish ethno-botanical information and biological activities of crude extracts from Commiphora swynnertonii against selected microbes of veterinary importance in chickens. Initially, a questionnaire survey was conducted to gather information on practices and knowledge on ethno-botanical uses of C. swynnertonii in the study area. Then extracts from different morphological parts of the study plant were tested against selected bacteria and fungi in vitro using agar well diffusion assay. Resin and root bark extracts showed significant activities (P < 0.001) against S. pyogenes, E. coli and B. subtilis compared to other extracts. The fungi, C. albicans and A. niger, were moderately inhibited. Antiviral activity of the resin and root bark extract was tested in ovo using embryonated chicken eggs inoculated with Newcastle disease virus (NDV). Both extracts significantly (P < 0.001) and effectively reduced virus titres. An animal trial was carried out using the resin and chickens experimentally infected with NDV. Results revealed significant reduction (P < 0.05) in clinical signs and mortality rates following administration of the resin before and after the infection. Prophylactic administration of the extract was found to be more effective than the therapeutic approach. HI titres decreased significantly (P < 0.001) in resin and root bark treated groups and in all chickens treated with resin irrespective of dose given and on whether the extract was administered before or after infection suggesting that the plant materials were capable of destroying the NDV before stimulating the developing chick‘s immunity. Another animal trial investigated the effect of the resin against experimental coccidiosis in chickens. Results showed that oral administration of the resin significantly (P < 0.001) reduced mortality rate. Safety margin of the resin was also investigated by determining its effects on selected physiological and biochemical parameters in chickens. The results revealed a good margin of safety provided that the dosage ranges between 200 to 800 mg resin/kg body weights. A phytochemical study was also carried to determine major bioactive compounds in the resin and root bark extracts. With these studies, it is concluded that extracts from C. swynnertonii especially resin, has significant antibacterial, antifungal, antiviral and anticoccidial effect against the selected microbes. Further research is required to test and validate the extract against other pathogens of medical and veterinary importance.
Comparative physiological, biochemical and behavioral responses to heat stress and low dietary energy in selected Tanzanian local chicken ecotypes
(Sokoine University of Agriculture, 2018) Khondowe, P.
As an important source of income and protein, local chickens are widely reared by a majority of rural and peri-urban households in many developing countries including Tanzania.However, these birds are seasonally exposed to challenging environments that includehigh temperatures and decreased scavengeable food materials.It was hypothesized that local chickens bred from different regions of Tanzania might have selected ecotypes with stronger tolerance to high temperatures andsuboptimal nutrition.Two groups of studies were conducted to compare effects of heat stressand low dietary energy in three Tanzanian chicken ecotypes: Kuchi (KU), Ching‟wekwe (CH) and Morogoro medium (MM). In the first study conducted at prevailing cyclic ambient temperatures, 4 weeks old hens wereeither fed a control diet containing 2864 Kcal/kgMEor diets containing 40 or 55% less energy than the control over a period of 7 weeks. Results showed ecotypespecific responses through differences in growth performance, feed conversion ratios (FCRs),behavioural responses, blood indices,and liver hsp70 and iNOS gene expressions.MM showed better performance at 55% restriction level whereas Kuchi exhibited better performance at 40% restriction and control energy levels. In the second study, the first batch of chickens was exposed to a constant temperature of 32±1°C for 7 days and thereafter raised and maintained at 37±1°C (8hrs per day) for 10 days, whereas the second batch was subjected to similar conditions but fed 55% less dietary energy than the control. Results showed ecotype-based differences in responses to both heat stress and a combination of heat stress with low dietary energy. MM had greater tolerance to heat stress and its combination with low dietary energy than KU and CH but similar to CH when only heat stress was applied, with respect to liver hsp70 gene expression and serum corticosterone.Collectively, the results show that growth performance and responses to heat stress and low dietary energy in the three local chicken ecotypes are different andhave provided starting points for future research to devise programs that include physiological, biochemical and behavioral traits that would enhance selection for heat and low dietary energy tolerance among the local chicken stocks.
Curcumin-based photosensitization inactivates aspergillus flavus and reduces aflatoxin B1 in maize kernels
(ELSEVIER, 2019) Temba, Benigni A.; Fletcher, Mary T.; Fox, Glen P.; Harvey, Jagger; Okoth, Sheila A.; Sultanbawa, Yasmina
Different methods have been applied in controlling contamination of foods and feeds by the carcinogenic fungal toxin, aflatoxin, but nevertheless the problem remains pervasive in developing countries. Curcumin is a natural polyphenolic compound from the spice turmeric (Curcuma longa L.) that has been identified as an efficient photosensitiser for inactivation of Aspergillus flavus conidia. Curcumin mediated photoinactivation of A. flavus has revealed the potential of this technology to be an effective method for reducing population density of the aflatoxin-producing fungus in foods. This study demonstrates the influence of pH and temperature on efficiency of photoinactivation of the fungus and how treating spore-contaminated maize kernels affects aflatoxin pro duction. The results show the efficiency of curcumin mediated photoinactivation of fungal conidia and hyphae were not affected by temperatures between 15 and 35 °C or pH range of 1.5–9.0. The production of aflatoxin B1 was significantly lower (p < 0.05), with an average of 82.4 μg/kg as compared to up to 305.9 μg/kg observed in untreated maize kept under similar conditions. The results of this study indicate that curcumin mediated pho tosensitization can potentially be applied under simple environmental conditions to achieve significant reduc tion of post-harvest contamination of aflatoxin B1 in maize.
Determination of tetracycline tesidues in honey from Tabora and Singida Regions Tanzania produced Using modern heehives
(2020-09) Sango, Mohamed Hamed; Mnyakavilli, Anna
A liquid chromatographic tandem mass spectrometric (HPLC MS/MS) method is proposed for identification and quantification of antibiotics residues and metabolites in honey and other matrices such as water, manure, soil, meat and sediments. This method was used to detect tetracycline derived residues in honey samples from Tabora and Singida regions, Tanzania. This honey was obtained from modern beehives. Three hundred honey samples were tested for the presence of tetracycline derivative residues. Of the examined samples 15% had these drug residues. Majority of samples contained residues to a proportion of 0.002–0.008 mg/kg. The findings show that tetracycline antibiotic residues are present in honey from Tabora and Singida regions, although in small concentrations, however, this can possibly influence the naturally occurring protective properties of this medicinal food. Also can lead to drug resistance to consumers. Prospective studies that simultaneously track both resistance genes and antibiotic residues will go far in resolving some of the gagging questions that cloud our understanding of antibiotic resistance dissemination
Effect of ambient temperature on daily milk yield and blood flow to the mammary gland in lactating goats treated with growth hormone
(Tanzania Veterinary Journal, 1990) Pereka, A. E.
The study was done with the objective of studying the effect or high temperature on the mammary gland production in terms or its blood supply and synthetic capacity. Growth hormone was injected to see whether high temperature has an interaction with the galactopoietic effects of the hormone in the mammary gland. Eight, one year old goats in their 6th week of lactation (1st lactation) were put into two climatic chambers, four in a chamber at 12°C and four in a chamber at 30°C. After four weeks of exposure to their respective temperatures two goats in each chamber were injected with bovine somatotropin (BST) daily for fifteen days. Daily milk yield was recorded. Blood flow rate was calculated from velocities measured using the Doppler Ultrasound Technique. Milk yield in goats at 30°C was 78% of milk yield of goats at 12°C at all times. With BST treatment milk yield increased by 9% and 13% at 12°C and 30°C respectively. Blood flow rate (L/day) to the mammary gland was in accordance to the milk yield with a blood flow rate: milk yield (CBF MY) ratio of 572 ± 166: 1 and 760 ± 180 : 1 at 12°C and 30°C respectively. With BST treatment the BF:MY ratio was 1059 ± 263 : 1 and 89 ± 38: 1 at 12°C and 30°C respectively. It is herewith concluded that blood flow to the mammary gland is a factor contributing to increased milk yield as it supplies the necessary nutrients for milk synthesis in the udder. The depressive effects of high ambient temperature can be counteracted by BST treatment as this increases milk yield not only through increased blood flow but also increased efficient nutrient extraction and utilization by the mammary gland cells for milk synthesis
Effect of different management systems on haematological parameters in layer chickens
(Sokoine University of Agriculture, 2013) Nyaulingo, Jumanne Magnus
A study was conducted at the Department of Animal Science and Production, Sokoine University of Agriculture. The aim was to study the effect of different management systems on haematological parameters in layer chickens. Three management systems which are battery cage, deep litter and semi- intensive were involved. Ninety layer chickens, Rhode Island Red, eight weeks old were used. Thirty chickens were placed in each of the three systems. Seven chickens from each management system were selected randomly for blood collection. Blood was collected in every two weeks for two months. Blood was used to analyse for hematological parameters. It was observed that, RBC (x 106/ μl), PCV (%), Hb (g %) increased as the age of chicken was increasing. ESR (mm), MCH (pg) and MCHC (%) decreased as age of chickens was increasing. All mean values for the RBC (x 106/ μl), and WBC (x104/ μl) count, PCV (%), Hb (g %), ESR (mm), MCH (pg) and MCHC (%) did not differ (P>0.05) significantly among the management systems. No significant effect of management system on hematological parameters was observed. The differences in the values of hematological parameters among the management systems observed to be probably due to changes brought about by age and individual bird variation. Concluding that RBC (x 106/ μl), PCV (%), and Hb (g %), had a direct relationship with age while ESR (mm), MCH (pg) and MCHC (%) were indirectly related. Since no significant effect was observed in the haematological parameters for the chickens under the three management systems, then other factors such as risk of diseases, sanitation, costs should be considered in deciding which system to be used. Deep litter system is advocated to be used by the poultry keeper because of its less cost and less risk of predators, and climatic extreme changes.
Effect of freezing on stability of oxytetracycline residues in beef from Dodoma region, Tanzania
(Tanzania Veterinary Associatian Proceedings, 2017-12-05) Mgonja, F.
The aim of this study was to determine the effect of freezing on the concentration of oxytetracycline (OTC) residues in beef samples stored at -20 °C (core beef temperature -12 °C and below) for 60 and 120 days. A total of 60 fresh beef samples were randomly obtained from cattle slaughterhouses and butcher shops in district in Dodoma region in Tanzania. The OTC residues were determined using high performance liquid chromatography (HPLC) with a diode array detector (DAD). Results showed that the mean concentration of OTC residues in 16 positive samples before freezing was 191.71 ± 90.21 ng/g. The mean concentration of OTC after freezing at -20 °C for 60 and 120 days were 166.40 ± 86.49 ng/g and 133.50 ± 83.24 ng/g respectively. These results revealed a significant (p<0.05) reduction of OTC residues of 30% after 60 days and 65% after 120 days of freezing at -20 °C. The percentage reduction of OTC residues was not dependent on the initial concentration or the freezing process but was rather due to unknown time dependent individual beef sample factors. It is concluded that. despite OTC levels in beef decreasing due to non-freezing factors. any residues significantly above Maximum Residues Level (MRL) may not be expected to reduce to acceptable levels as a result of freezing.
Effects of sweet potato leaves, roselle calyces and beetroot on body weight, selected hematological and biochemical parameters in broiler chicken
(Macrothink Institute, 2019) Max, Robert Arsen; Kitimu, Shedrack Reuben; Mshamu, Shaabani; Temba, Benigni Alfred; Muhairwa, Amandus P.
The study was conducted to assess the effects of sweet potato leaves, roselle calyces and beetroot tubers on body weight, selected hematological and biochemical parameters in broiler chickens. Eighty four (84) broiler chickens aged four weeks were randomly assigned into six groups of 14 chickens each. The first group (G0) remained as untreated control while the other groups were the treated groups which received 25% of ground sweet potato leaves (G1), rosella calyces (G2), beetroot tubers (G3) and their mixtures (G4 and G5) for 28 days. Following inclusion of these different vegetables, blood samples were collected and analyzed for selected hematological and biochemical parameters on day 0, 7, 14, 21 and 28. Results showed that consumption of the three vegetables caused significant decreases (p < 0.05) in body weight, serum glucose and cholesterol. On the other hand, hemoglobin concentration, packed cell volume (PCV) and total white blood cell (WBC) counts were shown to increase significantly (p < 0.05) compared to the control group. It is concluded that the hypoglycemic and hypocholesteremic effects in chickens following consumption of the three vegetables together with their positive effects on PCV and WBC counts are important qualities which can be utilized in the management of conditions such as obesity, diabetes mellitus, hyperlipidemia and cardiovascular diseases (atherosclerosis and coronary disease) in humans. Further studies in other animals are recommended.
Heat intolerance syndrome associated with foot and mouth disease in cattle in Tanzania: occurrence and Its effect on animal behaviour and physiological parameters
(Tanzania Veterinary Journal, 2006-01-30) Chibunda, R. T.; Makene, V. W.; Pereka, A. E.; Magayane, F. T.
A heat intolerance (HI) syndrome in cattle has been suspected to occur in Tanzania and is associated with previous exposure to foot and mouth disease (FMD) virus. For the present study, a survey was used to explore livestock keeper knowledge of its occurrence and association with FMD in Morogoro, Mwanza and Shinyanga regions. In addition, a field experiment was conducted to evaluate changes in behavioural activities and physiological parameters of HI cattle during variation of ambient temperatures. Large percentage (45.3%) of informants from Morogoro region reported occurrence of HI and associated it with FMD. Livestock keepers' perceptions of association between HI and FMD were confirmed by using the detection of antibody to FMDV. From the field experiment it was shown that HI animals had significantly (P< 0.001) higher rectal temperatures and respiration rates than health cows. Duration of grazing and rumination were significantly (P< 0.001) lowered in the HI cows than in the health ones during sunny days. Also, shade seeking was significantly (P< 0.001) higher in HI than in healthy animals. Furthermore, for HI animals grazing was higher during the morning and on cloudy days, than in late evening and sunny days respectively. It was also evident that HI animals preferred wallowing in water. Based on the knowledge of livestock keepers, from the present study, it is concluded that livestock keepers in Tanzania recognize HI as a disease, which sets in as a sequel to FMD outbreak. Based on the results from the field experiment it is concluded that during sunny days HI animals exhibit behavioural changes which reduces their feeding time.
Impact of climate variability and change on rain-fed farming system in selected semi-arid areas of Tanzania
(Sokoine University of Agriculture, 2015) Samwel, J. K.
Climate variability and change pose serious challenges to smallholder farmers and agro-pastoralists. Nonetheless, their trends and impacts on rain-fed farming system (RFFS) in semi-arid areas of Tanzania have not sufficiently been explored. This study was conducted in Iramba and Meatu districts to contribute to this knowledge gap. The study specifically (i) assessed meteorological data trends of rainfall and temperature between 1994 and 2011; (ii) determined farmers’ perception of climate variability and change in relation to meteorological data trends; (iii) determined changes in RFFS in response to climate variability and change; and (iv) examined changes in gender relations in response to climate variability and change. Although available meteorological data were less than 30 years suggesting climate variability, farmers’ perceptions covered up to 30 years and so addressed the question of climate change. A qualitative phase informed a household survey that covered a random sample of 388 households’ respondents (39% women). Qualitative data were transcribed into text and analyzed based on content and meaning of the text. Statistical Package for Social Sciences (SPSS) was used to analyze quantitative data. The results showed that there was no significant increase (P > 0.05) in inter-annual rainfall variability. However, seasonal rainfall variability showed a clear decreasing trend in April and December, in Iramba; and in January and April, in Meatu. Decreasing rainfall trend in April occurred simultaneously with increasing temperature trend. In addition, farmers’ perception and meteorological data trends compared well on change and on increased rainfall unpredictability as well as on increased warming and dry years. Nonetheless, due to missing data in some periods, meteorological data trends did not show increased frequency of drought since the 2000s as opposed to farmers’ perception. As hypothesized (P > 0.05), men and women’s perceptions were almost the same. Similarly, perceptions of the poor, not so poor and the rich were almost the same (P > 0.05). Unlike the hypothesis, the binary logistic regression model showed that climate variability and change had significant impact on changing crop varieties and livestock grazing places relative to non-climatic factors. Warming (ß = -10.61, Wald = 36.26, P ≤ 0.001) showed the highest impact on changing crop varieties. In addition, drought (ß = 2.16, Wald = 6.82, P ≤ 0.009) showed the highest impact on changing livestock grazing places. Based on division of labour, control over resources and biased norms, climate variability and change increased and perpetuated existing asymmetrical gender relations. The study concludes that although inter-annual rainfall had not changed significantly, temperature, drought and seasonal rainfall variability had intensified relative to the situation in the 1970s. This had substantial impacts on cropping and livestock systems and on gender relations. Therefore, strategies used by the farmers and interventions promoted by the government and Non-governmental Organizations (NGOs) to address the impacts should comprehensively consider seasonal variability with gender perspectives.
In-vitro wound healing properties of commiphora swynnertonii resinous extracts
(2021-09) Bakari, G. G.; Mshamu, S.A; Ally, M. H; Max, R.A; Bai, H
Wound healing is a complex multicellular process involving many cell types which include; inflammatory cells, endothelial cells, fibroblasts and keratinocytes. The process involves an orderly sequence of events with four overlapping phases namely; haemostasis, inflammatory, proliferation and remodeling phases. The process can be facilitated by the use of wound healing agents including herbal remedies from plants. In this study the main objective was to evaluate the in vitro wound healing activity of the resin obtained from Commiphora swynnertonii (C.swynnertonii). First the NIH -3T3 cells viability were evaluated using (3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyl Tetrazolium Bromide (MTT) assay. Then the wound scratch assay model was used to evaluate cellular proliferation, closure of the wound and release of matrix metalloproteinase enzymes. Results indicate differences in mean cell viability between different concentrations within 24 hours of incubation. The highest viability was recorded at the concentration of 1% (v/v). The in-vitro wound scratch assay showed positive NIH - 3T3 cells proliferation on the wound area and cells migration when compared with control group (without treatment) at 0 and 24 hours. In addition, C. swynnertonii was able to stimulate secretion of MMP-2 release from NIH - 3T3 cells. MMP-2 is an important enzyme for extracellular matrix remodeling during wound healing suggesting that C. swynnertonii promotes wound healing by stimulating cell proliferation and production of MMP-2 in a mechanism that is currently not known.
Inactivation of aspergillus flavus spores by curcumin-mediated photosensitization
(ELSEVIER, 2016) Temba, Benigni A.; Fletcher, Mary T.; Fox, Glen P.; Harvey, Jagger J. W.
Minimizing fungal infection is essential to the control of mycotoxin contamination of foods and feeds but many potential control methods are not without their own safety concerns for the consumers. Photo dynamic inactivation is a novel light-based approach which offers a promising alternative to conven tional methods for the control of mycotoxigenic fungi. This study describes the use of curcumin to inactivate spores of Aspergillus flavus, one of the major aflatoxin producing fungi in foods and feeds. Curcumin is a natural polyphenolic compound from the spice turmeric (Curcuma longa). In this study the plant has shown to be an effective photosensitiser when combined with visible light (420 nm). The experiment was conducted in in vitro and in vivo where A. flavus spores were treated with different photosensitiser concentration and light dose both in buffer solution and on maize kernels. Comparison of fungal load from treated and untreated samples was determined, and reductions of fungal spore counts of up to 3 log CFU ml 1 in suspension and 2 log CFU g 1 in maize kernels were obtained using optimal dye concentrations and light dose combinations. The results in this study indicate that curcumin mediated photosensitization is a potentially effective method to decontaminate A. flavus spores in foods and feeds.
Influence of storage conditions on efficacy of selected veterinary antimicrobials dispensed under different storage conditions in Morogoro, Tanzania
(Medtext Publications, 2019) Ally, M.H.S; Lusekelo, M
Efficacy of antimicrobials is of vital importance for patient safety and activity. The loss of potency may influence the efficacy and safety of antimicrobials. This study aimed to determine the influence of different storage conditions on the efficacy of selected antimicrobials. A significant statistical difference was observed across the efficacy data of selected antimicrobial brands. The data showed that the maximum reduction of efficacy was observed in light exposed antimicrobials compared to cool and properly store antimicrobials. These results authenticated that improper storage conditions resulted in failure to meet product characteristic and specification during shelf life. Optimum storage conditions and procedures ensure that the efficacy and integrity of medicinal products are maintained throughout their shelf life. This study emphasizes the importance of proper storage of antimicrobials from the time of their movement from manufacturing premises till reaches consumers.
The influence of weather on the occurrence of aflatoxin b1 in harvested maize from Kenya and Tanzania
(MDIP, 2021) Temba, Benigni A.; Darnell, Ross E.; Gichangi, Anne; Lwezaura, Deogratias; Pardey, Philip G.; Harvey, Jagger J.; Karanja, James; Massomo, Said M. S.; Ota, Noboru; Wainaina, James M.; Fletcher, Mary T.; Kriticos, Darren J.
: A study was conducted using maize samples collected from different agroecological zones of Kenya (n = 471) and Tanzania (n = 100) during the 2013 maize harvest season to estimate a relationship between aflatoxin B1 concentration and occurrence with weather conditions during the growing season. The toxins were analysed by the ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. Aflatoxin B1 incidence ranged between 0–100% of samples in different regions with an average value of 29.4% and aflatoxin concentrations of up to 6075 µg/kg recorded in one sample. Several regression techniques were explored. Random forests achieved the highest overall accuracy of 80%, while the accuracy of a logistic regression model was 65%. Low rainfall occurring during the early stage of the maize plant maturing combined with high temperatures leading up to full maturity provide warning signs of aflatoxin contamination. Risk maps for the two countries for the 2013 season were generated using both random forests and logistic regression models.
Intestinal lesions associated with transmucosal migration of eggs in calves and hamsters infected with schistosoma bovis
(University Copenhagen, Denmark, 1992) Semuguruka, William d
Schistosomiasis in livestock is recorded in many parts of Africa and appears to be widespread and endemic in northern, eastern and southern Africa (Hussein, 1968, Majid, 1980, Malek, 1969, Dinnik and Dinnik, 1965, Lawrence, 1978c). Although the disease is usually of a chronic nature in most livestock, there have been reports of acute infection, sometimes in outbreak proportions, among cattle in Sudan (Eisa,1966; Hussein, 1968), Zimbabwe (Lawrence, 1976, 1977d) and South Africa (Reinecke, 1970; Van Wyk et al , 1974). In a mainly slaughterhouse survey in Tanzania, Dinnik and Dinnik (1965) recorded infections in cattle of between 31-50% in northern, central and southern parts of the country. In a more recent epidemiological study in one region in Tanzania, Kassuku et al (1986) recorded a 30.8% prevalence rate of infection in cattle.
Maize milling and modifying atmospheric conditions limit formation of aflatoxin B1 by aspergillus flavus
(Macrothink Institute, 2021) Temba, Benigni Alfred; Bakari, Gaymary George
Occurrence of mycotoxins in foods poses a serious health concern all over the world. Aflatoxin B1 (AFB1) is the most toxic, with widest occurrence in various foods, but mainly in cereals and nuts and its accumulation depends on substrate and environmental factors. This study investigated the how physical status (milling) of maize kernels and atmospheric conditions (aeration, moisture and temperature) affect production of aflatoxin B1 by Aspergillus flavus (ATCC 28862). Intact kernels and flour were incubated for up to 20 days in open and partially sealed petri dishes under controlled temperatures of 25 ºC, 30 ºC and 37 ºC and initial moisture contents of 27%, 22%, 18%, 15% and 12%. It was found that on average, significantly higher (p < 0.05) aflatoxin B1 level was accumulated in intact kernels (145.7 µg/kg) as compared to milled kernels (2.2 µg/kg). Also, none of the samples incubated under partially sealed conditions, compared to up to 100% of the samples incubated in open atmosphere had detectable levels of aflatoxin B1 after 20 days. Fungal growth was not affected by milling or aeration, but sporulation was low at 37 ºC and high at 25 ºC and 30 ºC. The findings of this study provide baseline information on how conditions can be modified to control postharvest accumulation of aflatoxin B1 in cereals

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