Victoria O Adetunji

Victoria O Adetunji
University of Ibadan · Department of Veterinary Public Health and Preventive Medicine

DVM, MPVM, PhD, FCVSN

About

96
Publications
32,149
Reads
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1,064
Citations
Additional affiliations
July 1999 - present
University of Ibadan
Position
  • Professor (Full)
Education
May 2010 - September 2013
Fellowship, College of Veterinary Surgeons Nigeria(FCVSN
Field of study
  • Veterinary Public Health
August 2000 - August 2007
Department of Veterinary Public Health and Preventive Meddicine University of Ibadan
Field of study
  • Food hygiene and Veterinary Public Health

Publications

Publications (96)
Article
Full-text available
Background Escherichia coli is a major cause of poor microbial quality of milk, often resulting from unhygienic milk handling. Milk contamination poses public health concerns. Shiga toxin-producing Escherichia coli (STEC) strains in food products, particularly milk, is a critical concern for public health. Limited information exists on the detectio...
Article
Full-text available
Background Indiscriminate use of antimicrobials for the prevention and treatment of bacterial infection in animals is a common practice in Nigeria as in other developing countries. These antimicrobials are purchased over the counter without restrictions and often administered in form of medicated feedstuffs. In Nigeria, like most developing countri...
Article
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Escherichia coli (E. coli) is a common cause of poor milk microbial quality, often resulting from unhygienic milk handling. Here, a cross-sectional study was performed to determine the prevalence and antibiotic susceptibility profile of E. coli O157 in raw cow milk sold in Kwara State. Raw cow milk (n=1225) samples from 11 selected markets within t...
Article
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The paucity of information on the genomic diversity of drug-resistant bacteria in most food-producing animals, including poultry in Nigeria, has led to poor hazard characterization and the lack of critical control points to safeguard public health. Hence, this study used whole genome sequencing (WGS) to assess the presence and the diversity of anti...
Article
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Objectives The occurrence of multidrug drug-resistant (MDR) bacteria in poultry poses the public health threat of zoonotic transmission to humans. Hence, this study assessed the occurrence of drug-resistant E. coli in broilers in the largest live bird market in Kwara State, Nigeria in December 2020. Methods Presumptive E. coli isolates were isolat...
Article
Full-text available
Introduction: The COVID-19 vaccine is essential to reduce the global impact of the pandemic. Understanding its acceptance is key to Nigeria's national COVID-19 control strategies. Methods: Between the 6th and 22nd of January 2021, we conducted a non-probability convenience sampling of 3076 respondents using online and in-person interviews to assess...
Article
Introduction The COVID-19 vaccine is essential to reduce the global impact of the pandemic. Understanding its acceptance is key to Nigeria’s national COVID-19 control strategies. Methods Between the 6th and 22nd of January 2021, we conducted a non-probability convenience sampling of 3076 respondents using online and in-person interviews to assess...
Article
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Assessing knowledge, attitudes, and risk perception of Nigerian broiler grow-out farmers (n = 152) to antimicrobial resistance (AMR) with a five sectional purposive-structured-questionnaire: demographics; knowledge; attitudes; risk-perception; and response to regulation of antimicrobial practices. Data were analyzed using descriptive statistics, ch...
Article
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Background: Virulence genes are important in the pathogenesis of bacteria and in the mechanism of bacterial pathogenicity. Objective: The study aimed at molecular detection of virulence genes such as sdiA, fimH, InvA and fliC and determination of similarity and links among the isolates. Method: A total of 67 isolates including 4 controls were teste...
Article
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Milk handling practices in the Nigerian informal sector are usually poorly done. This is a threat to food safety and public health. We investigated the common practices by handlers involved in the milk processing and the contamination levels of raw cow milk marketed for consumption in Kwara State, Nigeria. In a cross-sectional survey, a pre-tested...
Article
In recent years, methicillin-resistant Staphylococcus aureus (MRSA) has gained interest in veterinary medicine due to its zoonotic potential. Currently, little information is available on the genotypic and virulence characteristics of MRSA isolates detected in Nigerian abattoirs. To better understand the epidemiology of MRSA associated with the aba...
Article
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Background: One of the major challenges that has driven the spread of Coronavirus Disease 2019 (COVID-19) worldwide is the burden of enforcing the preventive measures required to contain the pandemic. Enforcement of COVID-19 precautionary behaviour should not be homogenous; every country needs to be creative to ensure that humane considerations gui...
Article
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Objectives Antibiotics are important for improving animal health and production. However, the deposition of its residues in food of animal origin intended for human consumption at non-permissible levels has generated global health concern and the need to tackle this using the “One Health Approach”. This study assessed the knowledge and practice of...
Article
The occurrence of drug-resistant non-typhoidal Salmonella (NTS) in poultry has serious economic implications for the poultry industry and has the potential to cause human Salmonellosis. This study, therefore, aimed to determine the circulating serovars of NTS and their antibiotic susceptibility patterns in poultry in Ilorin. This cross-sectional st...
Article
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Escherichia coli O26 pose health risk to humans; it has been responsible for several outbreaks across the world, with associated cases of Haemolytic Uraemic Syndrome and death. Many studies in Nigeria have focused on E. coli O157:H7 in milk production chain, with paucity of research on other Shiga toxin E. coli. This study was therefore designed to...
Article
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Overwhelming empirical evidence has highlighted the contribution of indiscriminate antibiotic usage (ABU) in food animals to the overall burden of antibiotic resistance (ABR) in humans, thus making antibiotic use the main selective pressure driving antibiotic resistance. The social and behavioral perspective on antibiotic use and resistance in poul...
Article
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Occupational health and food safety risks are persistent challenges in food processing settings of most developing countries. This study assessed work-associated injuries and food safety risk perception among slaughterhouse employees. Workers (n = 203) were sampled randomly from five slaughterhouses and assessed with use of a structured questionnai...
Preprint
Full-text available
There are overwhelming empirical evidences highlighting the contribution of indiscriminate antibiotic usage (ABU) in food animals to the overall burden of antibiotic resistance (ABR) in humans, thus making antibiotic use the main selective pressure driving antibiotic resistance. Social and behavioral perspective on antibiotic use and resistance in...
Article
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industry while the Food and Drug Administration (FDA) regulates the HACCP in seafood , juice and egg industries. Particularly, FDA (2007) developed hazards and controls guides for the dairy industry, as well as the unhygienic and contaminated cheese products , which have most times been responsible for outbreaks of food poisoning.ABSTRACT Hazard An...
Article
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Meat contamination in abattoirs and meat markets has been associated with several factors. Of major concern is contamination due to pathogenic microbes present in food processing environments. This study investigated fungal contamination in meat markets and abattoir environments. Four meat markets (Olunloyo, Oja Oba, Olorunsogo, and Olodo) and thre...
Article
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The challenge of antimicrobial resistance (AMR) is grave in developing countries. Antimicrobials are misused yet stakeholders’ contribution to antimicrobial stewardship is low. Veterinary students are future prescribers and their knowledge could influence progress in combating AMR; hence, there is a need to assess their knowledge, attitude, and awa...
Article
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Background: The global increase in the use of antibiotics in poultry and livestock production has significantly resulted in the emergence of antibiotic resistant bacteria. There is a growing global concern of the effect of antibiotic resistance on both animals and humans. The aim of this study was to determine the antibiotic resistance profile of S...
Article
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Study Design: A questionnaire survey was carried out on 25 eateries from 7 local government areas (LGAs) in Ibadan. Eateries and LGAs were selected by convenience purposive sampling. Four eateries at the most, comprising of standard and substandard types were selected from each of the LGAs. The questionnaire was designed to get information on the h...
Article
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Foods of animal origin, especially poultry and poultry products, including eggs, have been consistently implicated in sporadic cases and outbreaks of human salmonellosis. Forty questionnaires were randomly distributed to people that came to purchase eggs at Bodija Market so as to assess the level of egg usage, preparation and consumption practices....
Article
Staphylococcus aureus is a zoonotic pathogen of significant public health concern. Information on the prevalence and risk factors facilitating bacterial colonization and spread under abattoir settings in Nigeria are scarce. This cross-sectional study was designed to determine prevalence of S. aureus as well as risk factors on knowledge and practice...
Article
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Aspergillus organisms have biofilm-forming abilities which make their control with some routine food-contact sanitizers or antifungal agents, more complicated. Studies on biofilm forming abilities of Aspergillus spp and its control are limited. This study was designed to investigate biofilm development by isolates of Aspergillus flavus and Aspergil...
Chapter
Worldwide, L. monocytogenes bacteria are frequently associated with illness in humans, where immunocompromised individuals and pregnant women are at high risk of contracting listeriosis. The pathogen most often spreads through food consumption, so it is a major concern in most food-processing environments. In Africa, however, research on L. monocyt...
Article
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Recreational use of water is often given inadequate consideration and care. This is of particular concern as the recreational use of water is becoming popular in Nigeria. Many of these are increasingly contaminated by domestic sewage and industrial effluents. This study is therefore relevant in assessing the environmental impact of microbes on ecot...
Article
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Hazard Analysis Critical Control Points of the production methods of farmyard processed Nigerian wara were determined using survey studies and oral interviews. Low to moderates ources of microbial hazards included boiling of fresh cowmilk containing Calotropis procera extracts, transfering of moulded wara into boiled cowmilk whey, included additi...
Article
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Meat is prone to contamination by pathogenic organisms during slaughter and processing due to unhygienic practices in Nigeria. In recent times, there has been an increase in the prevalence of antibiotic resistant foodborne pathogens due to increased drug misuse in livestock industry. We assessed the level of microbial contamination of fresh muscle...
Article
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Objective: To assess biofilms formed by different bacterial strains on glass slides, and changes in biofilm mass and biofilm-associated cell populations after brief contacts between biofilms and either media agar or food products. Methods: Two Listeria monocytogenes and Escherichia coli strains and a single Staphylococcus aureus strain were inocul...
Article
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Contamination levels of lead (Pb) and cadmium (Cd) in muscles, liver and kidney of 50 randomly selected, freshly slaughtered cattle in Ogun State, Nigeria were assessed using an official procedure and atomic absorption spectrophotometry. Results showed that Pb and Cd were present in all of the tested samples. Mean Pb concentrations were 0.721 ± 0.1...
Article
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Mycobacterium bovis causes classic bovine tuberculosis, a zoonosis which is still a concern in Africa. Biofilm forming ability of two Mycobacterium bovis strains was assessed on coupons of cement, ceramic, or stainless steel in three different microbiological media at 37°C with agitation for 2, 3, or 4 weeks to determine the medium that promotes bi...
Article
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This study assessed the biofilms formed by selected strains of Mycobacterium tuberculosis and investigated the efficacy of three different treatments to control the biofilms. Two M. tuberculosis strains were inoculated separately in 150 ml of Middlebrook 7H9-Tween 80 (0.1%) broth with 5% liver extract and 10% oleic albumin dextrose catalase (OADC)...
Article
Aim: Over the years, there have been considerable increases in the consumption of frozen poultry foods across Nigeria. Little attention has been paid to the microbial quality of these foods and hence constitutes a threat to public health. The contamination levels (Enterobacteriaceae and Listeria counts) and the presence of pathogenic E. coli, Salmo...
Article
Aims: This study was done to generate a baseline data on the effect of Bacillus cereus and its bacteriocin on the liver, kidney and reproductive organs in both sexes at different concentration. Methodology and results: B. cereus and its bacteriocin were injected intramuscularly in male and female Wistar rats at doses equivalent to 102 CFU and 104 C...
Article
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Smoking in Nigeria is the most affordable and widely used traditional fish processing method aimed at preserving or reducing losses. However, smoked fish can be a source of microbial hazard. This study assessed the biophysicochemical changes of fish muscles along the processing line of Oreochromis niloticus in Eleyele lake. A Structured questionnai...
Article
Aims: This study investigated the ability of bacteriocins isolated from Bacillus spp. (Bacillus species) to inhibit four different yeast isolates obtained from common food products (nono, yoghurt, ogi and cheese) commonly consumed by Nigerians with minimal heat treatment. Methodology and results: Forty-five Bacillus spp. was isolated and identified...
Article
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Escherichia coli O157:H7 is an important causative agent of severe gastrointestinal disease in humans. This study therefore aims at elucidating more information on the pathogenesis and haematological response of C. gariepinus experimentally infected with E. coli O157:H7. The test fish consist of 100 clinically healthy C. gariepinus (body weight 110...
Article
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After the discovery of indiscriminate antibiotic use in ready-for-slaughter cattle in south-western Nigeria, 90 tissue samples from randomly selected slaughtered cattle were evaluated for oxytetracycline and penicillin-G residues using high performance liquid chromatography and the data analysed by one-way Analysis of variance (ANOVA). The findings...
Article
The concentrations of lead (Pb) and cadmium (Cd) heavy metals in cow milk, goat milk butterfat, soft cheese and yoghurt samples were evaluated. Forty samples (eight of each sample) were analyzed using the atomic absorption spectrophotometer. There were detectable residual concentrations of Pb and Cd in all the 40 samples. The range of 0.0025 to 0.0...
Article
'Wara' soft cheese is traditionally produced in Nigeria and has a poor microbial quality. This study assessed the survivability of Listeria monocytogenes and other food spoilage microbes (enterobacteriacea, molds and yeasts) in vacuum packaged soft cheese treated independently with Carica papaya (Vcpc), Terminalia cattapa (Vtcc) crude extracts, nis...
Article
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The aim of this study was to assess biofilm formation by some pathogenic strains of E. coli and Salmonella sp. using glass and cement coupons, varying nutrient-culture media and two incubation temperatures (refrigeration (11°C) and room (28±2°C)). The Crystal Violet Binding Assay (CVBA) and Bacteria Cell Enumeration (BCE) methods were used to quant...
Article
This study was carried out to assess the level of heavy metals (lead (Pb) and cadmium (Cd)) and antibiotics (tetracycline and chloramphenicol) residues in frozen and fresh fish types obtained from Eleyele river, Officer's mess, Alfa farm and a major frozen meat outlet in Ibadan, Oyo State Nigeria. The Atomic Absorption Spectrophotometer (AAS) and H...
Article
This study determined the levels of tetracycline and heavy metals (lead and cadmium) levels in frozen chicken. One hundred frozen chicken muscle samples were sourced from major markets in Lagos and Ibadan (fifty samples each). The samples were analyzed using High Power Liquid Chromatography (HPLC) for tetracycline residue determination while Atomic...
Article
Full-text available
Biofilm formation in food processing is a public health concern globally. Biofilm formation in a 5 day period by various strains of Listeria on glass and cement was assayed using Crystal Violet Binding Assay (CVBA) and Bacteria Cell Enumeration (BCE) methods. Biofilm assessment was done in five different culture media and at two incubation temperat...
Article
Full-text available
Abstract: In this study, thirteen bacteria strains isolated along the processing line of sale of frozen poultry foods in retail outlets of Bodija market, Ibadan, Nigeria, were subjected to antibiogram assay using the Bauer-Kirby disc diffusion method. E. coli and Salmonella sp. displayed almost similar resistant patterns (50%) and were totally resi...
Article
The use of antibiotics may result in drug residues and the promotion of drug resistant strain of organisms. This study evaluated penicillin and amoxicillin residues in goat milk sourced from Ibadan city in South Western Nigeria. A total of one-hundred and sixty-six goat milk samples from Red Sokoto and West African breeds of goats were analysed usi...
Article
The processing line of West African soft cheese varieties (processed with Calotropis procera (Sodom apple) and Cymbopogon citratus (lemon grass) leaf extracts was assessed for nutrient compositions ( nitrogen, crude protein, fat, lactose, moisture content ), pH , total aerobic plate count and trace elements (Fe, Zn, Cu, Mn, Na, Ca, Mg and K) . The...
Article
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In Nigeria, inadequate supply of pipe borne water is a major concern; hence many homes have wells sited around the house at a distance from the septic tanks. These wells serve as major source of water for household uses like drinking, cooking, washing etc. Septic tanks are leading contributors to the total volume of waste discharged directly to gro...
Article
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This study assessed bacteria hazards in goat processing line.Goat meat has become an important source of protein to the teaming Nigerian populace. Unhygienic processing of carcasses and inadequate sanitary conditions of the abattoir poses health risks to consumers. Enterobacteriaceae and Total Aerobic Plate Counts were assayed along the processing...
Article
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Adhesion of bacteria to meat processing surfaces may act as potential sources of transmission of pathogens in meat industry. Several studies have shown that adhesion of bacteria to surfaces partly depends upon the nature of the inert surfaces and partly upon the bacterial surface properties. The aim of this study was to compare the adhesion of E. c...
Article
Fifty-eight samples (40 cheese and 18 yoghurt samples) were collected from five soft cheese and two conventional yoghurt processors. The samples were collected along the processing lines of these dairy products and analyzed for antibiotic residues (streptomycin, penicillin-G and tetracycline). The mean residual levels for cheese was; streptomycin (...
Article
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This study assessed total aerobes and anaerobes in vacuum packaged 'wara' a West African soft white cheese processed with lemon juice as coagulant. The cheese was treated with Carica papaya (Vcpc), Terminalia cattapa (Vtcc) crude extracts, nisin (Vnc), and the combination of these three treatments (V+3) and stored at 15 and 28ºC for a three weeks s...
Article
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Bacillus is an interesting genus to investigate since it produces a diverse array of antimicrobial peptides representing several different basic chemical structures. The production of bacteriocins or bacteriocin-like substance has already been described for B. substilis, B. stearothermophilus and other Bacillus sp. The present study assessed the ef...
Article
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Critical Control Points (CCPs) associated with the processing of cheese in five local cheese factories and yoghurt in two conventional processing factories, located in Morin, Kwara state, Nigeria were identified using flow diagrams and microbial assay for detection of E. coli and Listeria monocytogenes. Fifty- eight (58) samples were collected alon...
Article
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Antibiotics sensitivity test was assayed on thirty (30) isolates (10 each for Escherichia coli, Listeria and Salmonella) from retail meat (beef) tables in Ibadan municipal abattoir, Nigeria. The isolates were tested for sensitivity for eight (Listeria) and ten (Escherichia coli and Salmonella) commonly used antibiotics using Bauer-Kirby disc diffus...
Conference Paper
Virulence of food processing relevance in bacteria isolates are determined by the measurement of several factors such as; biofilm production, adherence factor and exopolysaccharide production. The ability of bacteria to form biofilm has been suggested to play a vital role in the pathogenesis of numerous bacterial species. Listeria count and Identif...
Article
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Meat display tables have been implicated as one of the sources of meat contamination and a critical control point in food processing. Cleaning and disinfection operations are of great importance within the food processing industries for food safety reasons. The effectiveness of four cleaning agents as treatments for the reduction of microbial co...
Article
Forty strains out of 246 of Bacillus spp isolates from common food products were found to produce proteinaceous substances which showed antimicrobial activity against strains of Salmonella enteritidis (3), Micrococcus luteus (1) and Staphylococcus aureus (2). The zones of inhibition ranged between 5.90±0.000 -27.00±0.000 mm. Three bacteriocin produ...
Article
This study investigated the influence of sodium chloride concentrations (0.1-0.5%) and temperatures (ambient (26-28°C); refrigerator(4-11°C) on antimicrobial activity of bacteriocin from Bacillus spp. Three bacteriocins from Bacillus spp were tested against Staphylococcus aureus2, Salmonella enteritidis3 and Micrococcus luteus1. Zones of inhibition...
Article
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A bacteriological assay was done on meat tables in Ibadan municipal abattoir, Nigeria. Swab samples from 1 cm of the surface were obtained from meat tables before and after the sales of meat. The 2 swab samples were analyzed for Listeria sp Count (LSC), Listeria monocytogenes Count (LMC), Coliform Count (CC), Enterobacteriaceae Count (EC) and Salmo...
Article
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Microorganisms attach to surfaces and develop biofilms which are a concern in food and environmental safety. This study, quantified biofilms in 20 isolates viz: Listeria monocytogenes (14) and Listeria spp (6) from meat tables in Ibadan municipal abattoir, Nigeria on wood, glass and steel surfaces using crystal-violet binding assay. Listeria isolat...
Article
Full-text available
Micro-organisms attach to surfaces and develop biofilms which are a concern in food and environmental safety. This study, quantified biofilms in 20 isolates viz: Listeria monocytogenes (14) and Listeria spp (6) from meat tables in Ibadan municipal abattoir, Nigeria on wood, glass and steel surfaces using crystal-violet binding assay. Listeria isola...
Article
This study aimed at evaluating the survivability of Listeria monocytogenes and members of the Enterobacteriaceae group of organisms during the processing and storage of wara, a southwestern Nigerian un-ripened soft cheese. Pasteurized milk inoculated with L. monocytogenes at 10(1) or 10(2) CFU/ml was used to process the cheese. Samples were taken a...
Article
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The study evaluated the molluscicidal effects of ethanolic leaf extracts of two Nigerian indigenous medicinal plants; Terminalia catappa and Carica papaya. Different concentrations 2500, 630, 160, 40 and 10 ppm were prepared from the stock solution of the extracts. Adult Biomphalaria pfeifferi and Bulinus globosus were exposed to these different gr...
Article
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Three strains of Escherichia coli 0157:H7 and eleven strains of Listeria monocytogenes isolated from West African wara cheese were analysed for cellulose production, fimbriae formation, zetapotential and biofilm formation which are of relevance in food processing. E. coli c produced no fimbria, very low cellulose and significantly lower zetapotenti...
Article
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This study introduced vacuum packaging into wara a West African soft cheese storage.Wara was vacuum packaged and stored in whey. Samples were taken during 5 and 21 day storage period at 15 and 28°C to determine populations of total aerobes(TA), anaerobes, Enterobacteriacea, psychrotrophs, as well as molds and yeasts(M/Y) in Log10 CFUg-1. TA increas...
Article
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The nutritional contents of Carica papaya and Calotropis procera processed cheeses were evaluated. The following nutrients and elements were assayed; fat, protein, moisture, sugar, Zn, Mn, Fe, and Cu and their values were 22.3 and 31.45%, 31.60 and 33.84%, 62.5 and 61.70%, 2.05 and 8.10%, 1.19 and 4.14%, 2.80 and 2.35%, 4.8 and 4.7%, 4.6 and 7.3% f...
Article
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An ascitic adult Clarias gariepinus weighing 530g with a total length of 37cm was discovered during harvest and presented to the fish and wildlife disease investigation clinic with hyperaemic lesions on the ventral aspect of the operculum. The fish was anaesthetized, observed grossly and necropsied. Tissue samples were taken for histo-pathological...
Article
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L’effet de la listeria monocytogenes sur les paramètres de spermes de huit boucs nains de l’Afrique occidentale a été étudié après une inoculation intra-scrotale de la listeria monocytogenes en bouillon de culture. Le volume de sperme collecté (ml) et le taux de motilité (%) des spermes a diminué de façon significative (P<0,05) par rapport à leurs...
Article
Full-text available
This study evaluated the survival of Enterobacteriaceae, molds and yeasts in vacuum-packaged soft cheese treated independently with crude extracts of Carica papaya (Vcpc) and Terminalia cattapa (Vtcc), a bacteriocin (Vnc), and a combination of the three treatments (V+3). The cheese was then stored at 15 and 28°C, respectively, for three weeks. Ente...
Article
Full-text available
Quantification of biofilm formation by 40 Listeria monocytogenes strains from wara soft cheese and its processing environment was assessed on glass vials surfaces. Attachement to glass surface was quantified using a crystal violet binding assay. All the 40 strains produced biofilms after 48 and 72 h incubation at 37°C. No biofilms were formed at 24...
Article
As an important protein source for West African consumers, wara cheese made from the leave extract of Calotropis procera has extremely short shelf life of only 2–3 days [Adegoke, G. O., Nse, E. N., & Akanni, A. O. (1992). Effects of heat, processing time, and pH on the microflora, aflatoxin content, and storability of wara, a soft white cheese. Die...
Article
Full-text available
Sommaire L'effet de la listeria monocytogenes sur les paramètres de spermes de huit boucs nains de l'Afrique occidentale a été étudié après une inoculation intra-scrotale de la listeria monocytogenes en bouillon de culture. Le volume de sperme collecté (ml) et le taux de motilité (%) des spermes a diminué de façon significative (P<0,05) par rapport...