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This study investigated the aflatoxin production potentials of selected fungi using a polyphasic approach. Internally transcribed spacer region of the fungi was amplified using the polymerase chain reaction. Forty-five Aspergillus strains were further assessed for aflatoxin production using the conventional methods such as growth on yeast extract sucrose, &beta ; -cyclodextrin neutral red desiccated coconut agar (&beta ; -CNRDCA) ; expression of the aflatoxin regulatory genes and the use of both thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). A large proportion (82.22%) of the isolates harbored the Nor-1 gene while 55.56%, 68.89%, and 80% possessed the ver-1, omt-A, and aflR genes, respectively. All 100% the isolates harbored the aflJ gene. Twenty-three isolates were positive for aflatoxin production based on the yeast extract sucrose medium (YES) test ; ammonium vapor test (51%), yellow pigment production (75.5%), and &beta ; -CNRDCA tests ; and blue/green fluorescence (57.7%). Based on TLC detection 42.2% produced aflatoxins while in the HPLC, total aflatoxin (AFTOT) production concentrations ranged from 6.77&ndash ; 71,453 µ ; g/g. Detectable aflatoxin B1 (AFB1) concentrations obtained from the HPLC ranged between 3.76 and 70,288 µ ; g/g ; 6.77 and 242.50 µ ; g/g for aflatoxin B2 (AFB2) ; 1.87 and 745.30 µ ; g/g for aflatoxin G1 (AFG1) ; and 1.67 and 768.52 µ ; g/g for aflatoxin G2 (AFG2). AFTOT contamination levels were higher than European Union tolerable limits (4 µ ; g/kg). The regression coefficient was one (R2 = 1) while significant differences exist in the aflatoxin concentrations of Aspergillus (p &le ; 0.05). This study reports the potentials of Aspergillus oryzae previously known as a non-aflatoxin producer to produce AFG1, AFG2, AFB1, and AFB2 toxins. Aspergillus species in feedlots of animals reared for food are capable of producing aflatoxins which could pose hazards to health.

Currently there is concern with respect to the occurrence of mycotoxins in feed commodities, which could result in the loss of animal production and danger to consumers. Recent legislation to control the trading of such contaminated materials has been initiated with the result that it is imperative to be able to analyse for mycotoxins in feed commodities, rapidly and with sufficient accuracy to ensure that bulk cargoes of such materials are within set safety limits. To this end a large batch (800 tonnes) of cotton-seed meal was consigned to a South African feed miller and was sampled according to a protocol devised under the European Union Framework 6 Biotracer programme. These were split and analysed for aflatoxins (AFs) by two laboratories using the VICAM fluorimetry aflatoxin method (VF) and by an high performance liquid chromatography (HPLC) method (HPLC) as part of another study to determine the statistical variation of using composite samples derived from a large bulk cargo (Reiter et al., 2011) . The results from the HPLC method showed that all the composites were contaminated with aflatoxins (AF) ranging from 24 – 93μg/kg. A comparison of the two analytical methods used, showed that the results compared in terms of trend but in general the Vicam fluorimetry method (VF) gave a higher concentration of aflatoxin B1 (AFB1) ranging between 26 – 164μg/kg. The levels of AF found were in several cases higher than those permitted by current legislation and would not have been allowed into the European Union. The methodology used allowed for reduced sampling and a more rapid method of analysis to assess AF contamination in commodities, subject to further development. The predominant fungi isolated and identified were Aspergillus flavus and parasiticus, which are main producer of AFs in the environment.

Agricultural products, especially cereal grains, serve as staple foods in sub-Saharan Africa. However, climatic conditions in this region can lead to contamination of these commodities by moulds, with subsequent production of mycotoxins posing health risks to both humans and animals. There is limited documentation on the occurrence of mycotoxins in sub-Saharan African countries, leading to the exposure of their populations to a wide variety of mycotoxins through consumption of contaminated foods. This review aims at highlighting the current status of mycotoxin contamination of food products in Zimbabwe and recommended strategies of reducing this problem. Zimbabwe is one of the African countries with very little information with regards to mycotoxin contamination of its food commodities, both on the market and at household levels. Even though evidence of multitoxin occurrence in some food commodities such as maize and other staple foods exist, available published research focuses only on Aspergillus and Fusarium mycotoxins, namely aflatoxins, deoxynivalenol (DON), trichothecenes, fumonisins, and zearalenone (ZEA). Occurrence of mycotoxins in the food chain has been mainly associated with poor agricultural practices. Analysis of mycotoxins has been done mainly using chromatographic and immunological methods. Zimbabwe has adopted European standards, but the legislation is quite flexible, with testing for mycotoxin contamination in food commodities being done voluntarily or upon request. Therefore, the country needs to tighten its legislation as well as adopt stricter standards that will improve the food safety and security of the masses.

Agricultural products, especially cereal grains, serve as staple foods in sub-Saharan Africa. However, climatic conditions in this region can lead to contamination of these commodities by moulds, with subsequent production of mycotoxins posing health risks to both humans and animals. There is limited documentation on the occurrence of mycotoxins in sub-Saharan African countries, leading to the exposure of their populations to a wide variety of mycotoxins through consumption of contaminated foods. This review aims at highlighting the current status of mycotoxin contamination of food products in Zimbabwe and recommended strategies of reducing this problem. Zimbabwe is one of the African countries with very little information with regards to mycotoxin contamination of its food commodities, both on the market and at household levels. Even though evidence of multitoxin occurrence in some food commodities such as maize and other staple foods exist, available published research focuses only on Aspergillus and Fusarium mycotoxins, namely aflatoxins, deoxynivalenol (DON), trichothecenes, fumonisins, and zearalenone (ZEA). Occurrence of mycotoxins in the food chain has been mainly associated with poor agricultural practices. Analysis of mycotoxins has been done mainly using chromatographic and immunological methods. Zimbabwe has adopted European standards, but the legislation is quite flexible, with testing for mycotoxin contamination in food commodities being done voluntarily or upon request. Therefore, the country needs to tighten its legislation as well as adopt stricter standards that will improve the food safety and security of the masses.

Objective: To establish and estimate prevalence of contagious bovine pleuropneumonia (CBPP), using slaughter slabante-mortem examination and postmortem lesions as a diagnostic tool in slaughtered cattle in Chavuma, Northwestern province, Zambia. Methods: Between August and December 2020, 364 cattle were slaughtered at six slaughter slabs in Chavuma district (Good Hope, Likola Levy, Supplies of Chavuma Boarding school, Formula Butchery, Grace of God, Never Lose Hope).The affected cattle had noisy breathing, nasal discharge and coughing. In addition, to yellow fluid in the chest cavity and lungs coated in yellowish substance lung lesions. This was according to the ante-mortem and postmortem reports. Results: Hundred and five (28.8%) of the slaughtered cattle had gross lung lesions suggestive of CBPP. When compared to other slaughter slabs, the point prevalence of positive CBPP postmortem lesions was higher at Grace of God slaughter slab (P<0.05). Labored breathing (78%), dry cough (70%), and mucopurulent nasal discharge were the most common pneumonic signs (60%). The gross characteristic of CBPP postmortem lesions included the following; L/lung (45%), R/lung (28%), Both/lung (30%), P/adhesion (90%), L/pinkish (65%), Sequestra (20%) and Yellow fluid (60%). However, the frequently encountered was P/adhesion (90%), and pinkish lung (65%). Conclusions: CBPP remains an issue in Chavuma district, and possibly Northwestern province as a whole, according to the findings of this study. Furthermore, since movement control is difficult in Chavuma district and herds are not restricted, testing and slaughter, even when combined with vaccination, may not be sufficient to control the disease. In the fight against disease, communities play a crucial role. To be effective, any government CBPP control systems must be thoroughly communicated to livestock farmers so that they are fully engaged, recognize the long-term benefits, and are willing to comply. Apart from that, a continued monitoring program is recommended, which ...

This study investigated the aflatoxin production potentials of selected fungi using a polyphasic approach. Internally transcribed spacer region of the fungi was amplified using the polymerase chain reaction. Forty-five Aspergillus strains were further assessed for aflatoxin production using the conventional methods such as growth on yeast extract sucrose, β-cyclodextrin neutral red desiccated coconut agar (β-CNRDCA); expression of the aflatoxin regulatory genes and the use of both thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). A large proportion (82.22%) of the isolates harbored the Nor-1 gene while 55.56%, 68.89%, and 80% possessed the ver-1, omt-A, and aflR genes, respectively. All 100% the isolates harbored the aflJ gene. Twenty-three isolates were positive for aflatoxin production based on the yeast extract sucrose medium (YES) test; ammonium vapor test (51%), yellow pigment production (75.5%), and β-CNRDCA tests; and blue/green fluorescence (57.7%). Based on TLC detection 42.2% produced aflatoxins while in the HPLC, total aflatoxin (AFTOT) production concentrations ranged from 6.77–71,453 µg/g. Detectable aflatoxin B1 (AFB1) concentrations obtained from the HPLC ranged between 3.76 and 70,288 µg/g; 6.77 and 242.50 µg/g for aflatoxin B2 (AFB2); 1.87 and 745.30 µg/g for aflatoxin G1 (AFG1); and 1.67 and 768.52 µg/g for aflatoxin G2 (AFG2). AFTOT contamination levels were higher than European Union tolerable limits (4 µg/kg). The regression coefficient was one (R(2) = 1) while significant differences exist in the aflatoxin concentrations of Aspergillus (p ≤ 0.05). This study reports the potentials of Aspergillus oryzae previously known as a non-aflatoxin producer to produce AFG1, AFG2, AFB1, and AFB2 toxins. Aspergillus species in feedlots of animals reared for food are capable of producing aflatoxins which could pose hazards to health.

Recently, methods to analyze aflatoxin M1 (AFM1) in milk and dairy products have been developed for both screening purposes (i.e., rapid, economical, and simple methods) and for confirmation by accurate, reproducible, and sensitive quantification. The aim of this study was to evaluate the efficiency of different rapid kits and techniques available on the market by using different analytical methods: thin layer chromatography (TLC), immunoaffinity column, AFM1 immunochromatographic strip, and ELISA; some samples were also submitted to HPLC for comparison of results. One hundred thirty-eight samples were collected from rural subsistence and commercial dairy farms in selected areas of Egypt and South Africa and analyzed for the presence of AFM1. The results obtained by AFM1 immunochromatographic strip indicated the lowest frequency of occurrence, with a detection incidence of 20.45% in Egyptian samples and 16% in South African samples. Aflatoxin M1 was detected by ELISA in 65 (73.9%) Egyptian milk samples, with a range of 8.52 to 78.06 ng/L, and in 34 (68%) South African milk samples, with a range of 5 to 120 ng/L. A higher incidence of AFM1 in Egyptian milk samples was shown by TLC (81.8%) compared with ELISA (73.9%). Samples analyzed by ELISA in South African milk samples demonstrated satisfactory correlation when compared with HPLC coupled with Coring cell (an electrochemical cell for the derivatization of AFM1). Among the positive samples, 18 of the Egyptian samples (20.45%) positive by ELISA had levels of AFM1 above the European Union (EU) regulatory limit (50 ng/L), whereas 65 samples (73.9%) were above the Egyptian regulatory limit (0 ng/L). Six of the South African samples (12%) tested by ELISA were above the South African (50 ng/L) and EU regulatory limits. The mean concentration of AFM1 was 25.79 ng/L in Egyptian samples and 17.06 ng/L by ELISA and 39 ng/L by HPLC in South African samples. These contamination levels would not represent a serious public health hazard according to EU legislation.