The effect of bambermycin, carbadox, chlortetracycline and olaquindox on antibiotic resistance in intestinal coliforms: a new animal model

Groups of germ-free mice kept in isolators and associated with faecal microflora from piglets were continuously given either water or a solution of one of the following: chlortetracycline (20 micrograms/ml), carbadox (50 micrograms/ml), olaquindox (50 micrograms/ml), bambermycin (flavomycin) (5 micrograms/ml) or mixtures of these drugs. The proportions of lactose-fermenting bacteria in their faeces which were resistant to chlortetracycline, carbadox or olaquindox were measured by a comparative plate-counting procedure. Compared to occurrence in control mice, the occurrence of antimicrobial drug-resistant bacteria was higher in mice receiving chlortetracycline (P less than 0.001) and lower in mice receiving bambermycins (P less than 0.005). In contrast, olaquindox and carbadox did not change the proportion of resistant coliforms in mice faeces. A control experiment was conducted with five groups of germ-free mice given the same flora and kept without drugs in separate isolators. No difference in the occurrence of resistant coliforms could be found between these groups. The germ-free mouse associated with faecal microflora from a conventional animal seems to be a suitable model for determining in vivo the effect of low doses of antimicrobial drugs on drug resistance in lactose-fermenting enteric flora

A Risk Assessment and Hazard Analysis and Critical Control Point (HACCP) Study for the Irish Catering Industry

End of project reportThis report provides details of a food safety knowledge survey, a microbiological survey, a chilled temperature survey and an audit conducted in 200 restaurants throughout the island of Ireland. The results suggest a low incidence of several bacterial pathogens (including Salmonella enterica) and identify areas in which food safety knowledge, procedures and practices should be improved. Salmonella enterica isolates were characterised and the results suggested distinct pockets of different serotypes. Growth curves for L. monocytogenes isolates suggest considerably reduced shelf-life for a variety of foods. For example, lettuce should not be stored at room temperature or the shelf-life is reduced from 6.5 days (chilled storage) to 3.3 days.The predicted shelf-life for fresh milk was 4.5 days (chilled storage). Chlorine (sodium hypochlorite, 5 ppm), 1-monolauroyl-rac-glycerol and a laurate ester (ester-glucoside laurate) were also tested for application as vegetable decontaminating agents in restaurant kitchens. The report concludes with recommendations for improved food safety and hygiene in Irish restaurants.Safefoo

An update on environmental mastitis: challenging perceptions

Environmental mastitis is the most common and costly form of mastitis in modern dairy herds where contagious transmission of intramammary pathogens is controlled through implementation of standard mastitis prevention programmes. Environmental mastitis can be caused by a wide range of bacterial species, and binary classification of species as contagious or environmental is misleading, particularly for Staphylococcus aureus, Streptococcus uberis and other streptococcal species, including Streptococcus agalactiae. Bovine faeces, the indoor environment and used pasture are major sources of mastitis pathogens, including Escherichia coli and S. uberis. A faeco-oral transmission cycle may perpetuate and amplify the presence of such pathogens, including Klebsiella pneumoniae and S. agalactiae. Because of societal pressure to reduce reliance on antimicrobials as tools for mastitis control, management of environmental mastitis will increasingly need to be based on prevention. This requires a reduction in environmental exposure through bedding, pasture and pre-milking management and enhancement of the host response to bacterial challenge. Efficacious vaccines are available to reduce the impact of coliform mastitis, but vaccine development for gram-positive mastitis has not progressed beyond the “promising” stage for decades. Improved diagnostic tools to identify causative agents and transmission patterns may contribute to targeted use of antimicrobials and intervention measures. The most important tool for improved uptake of known mastitis prevention measures is communication. Development of better technical or biological tools for management of environmental mastitis must be accompanied by development of appropriate incentives and communication strategies for farmers and veterinarians, who may be confronted with government-mandated antimicrobial use targets if voluntary reduction is not implemented

Evaluation of the Microbial Pollution of Water in Ramasandra Lake, Bangalore, Karnataka and Assessment of Multiple Antibiotic Resistance among Escherichia Coli

An experiment was designed to examine microbiology of water samples of Ramasandra Lake and further assess the occurance of the multiple antibiotic resistance of E coli. Analysis of the water samples obtained from the lake indicates high microbial and fecal contamination with microbial load in order of 105 and MPN >1800/100ml. Collected water samples from four stations were screened for the E coli to assess their resistance to 10 different antibiotics. Of the 14 E coli isolates 0% were susceptible to all antibiotics used. The isolates were found resistance to penicillin and tetracycline (100%). Among the 10 antibiotics tested, four pattern of antibiotics resistance were obtained and all of them were multiple antibiotic resistance with the number of antibiotics ranging from 2 to 7. The result indicates the developing antibiotic resistant E coli may be a serious threat on public health, aquatic organisms and environment

Antibiotic-resistant Escherichia coli in wastewaters, surface waters, and oysters from an urban riverine system

antibiotic resistance (AR) patterns of 462 Escherichia coli isolates from wastewater, surface waters, and oysters were determined. Rates of AR and multiple-AR among isolates from surface water sites adjacent to wastewater treatment plant (WWTP) discharge sites were significantly higher (P < 0.05) than those among other isolates, whereas the rate of AR among isolates from oysters exposed to WWTP discharges was low (< lKc)

Impact of bacteria and yeast with probiotic properties on performance, digestibility, health status and gut environment of growing pigs in Vietnam

This thesis aimed to evaluate the effects of six lactic acid bacteria (LAB) strains and Bacillus subtilis H4, Saccharomyces boulardii Sb, and a microbial enzyme mixture, supplemented to basal diets on the performance, diet digestibility, health status, and gut environment of growing pigs under Vietnamese conditions. The results showed that three different 3-strain-LAB complexes, comprising combinations of Enterococcus faecium 6H2, Lactobacillus acidophilus C3, Pediococcus pentosaceus D7, L. plantarum 1K8 and L. plantarum 3K2 improved performance, digestibility, health status and gut environment of the LAB-supplemented piglets in the first two weeks post-weaning (Per I), but not in the following 3 weeks (Per II). Adding an LAB strain (L. fermentum NC1) alone or combined with the Bacillus, or combined with a Bacillus and yeast complex, to a 3-strain-LAB complex showed improvements in the performance, diet digestibility, health status and gut environment of the probiotics-supplemented piglets in both Per I and II. The inclusion of Bacillus resulted in higher nutrient digestibility, and the addition of Saccharomyces showed improvements in the scouring scores of the piglets. Supplementation with either a microbial enzyme mixture alone or a combination of a 3-strain-LAB complex and yeast in a weaner diet improved the performance and diet digestibility in piglets in Per I. In Per II, no changes in performance or digestibility were found in enzymes-fed piglets, while improved performance and diet digestibility were obtained in piglets fed the LAB-yeast diet. There was lack of response of piglets to this enzyme mixture when these enzymes were supplemented to the diet that contained the complex of LAB and yeast in both Per I and II. Dietary supplementation with the combination of Bacillus, Saccharomyces and 4-strain-LAB complex had positive effects on performance and digestibility in grower pigs, but not in finisher pigs, while supplementation with the Bacillus alone or combined with Saccharomyces did not affect the performance and digestibility in grower and finisher pigs. The results of these studies suggest that combinations of suitable strains of Bacillus, Saccharomyces and LAB can be used as an alternative to antibiotic feed additives in pig production under the conditions of Vietnam

Antibiotic Susceptibility Patterns of Bacteria Species Isolated from Ice-cream Vended in Ota and Lagos Metropolis

Background: Most milk and milk products (ice-cream) could be a veritable avenue for the transmission of multidrug resistant genes among any community. In this study, antibiotic susceptibility patterns were surveyed in some selected ice-cream sold in Ota and Lagos metropolis. Materials and Methods: Samples of branded ice-creams were surveyed for antibiotic susceptibility patterns, a total of 9 bacteria species were selected from the pool of isolates and characterized morphologically and biochemically. The antibiotic reactions of the isolates assigned as D1, D2, D3, G1, G2, G3, J1, J2 and J3 to the standard Gram negative and Gram positive antibiotics was done by agar diffusion method. Results: Based on the comparison of the isolates with standard reference organisms, the isolates belonged to the Salmonella, Pseudomonas, Yersinia, Staphylococcus and Micrococcus species. Most of the organisms exhibited antibiotic reactions ranging from susceptible, intermediate to resistance to the assayed standard antibiotics. Conclusion: From this study, the incidence of antibiotic resistance patterns could be on the increase unless strict measure during processing and handling of ice-cream is ensured

Incidence of Bacteria with Potential Public Health Implications in Raw Lycopersicon esculentum (Tomato) Sold in Lagos State, Nigeria

ABSTRACTLycopersicon esculentum (tomato) is a fleshy berry that is highly perishable and prone to microbial spoilage. The presence of some microorganisms of public health significance makes it a potential health hazard to consumers. There is therefore the need to determine the food safety and public health implications of some of the microorganisms present in it. The aim of the study was to isolate, identify and compare the incidence of the organisms that could be potential pathogens among the four grades of tomato samples used in the investigation. Seven batches of tomato samples were obtained from two (2) major produce markets in Lagos Nigeria. A total of 40 isolates were obtained from the tomato samples. Staphylococcus aureus (22.5%), Escherichia coli (15%), Bacillus species (20%) and Salmonella species (5%) were among the bacteria isolated from the tomato samples. The average pH values of the tomato samples ranged from 4.34 to 4.60 while the average moisture content of the tomato samples was between 12% and 95.1%. The results showed that the freshness and hardness of tomato samples were important factors which determine the types of bacteria found on them. As some of the bacterial genera identified are potential food-borne pathogens that could pose some public health challenges, proper handling and adequate cooking before consumption is suggested

The effects of amoxicillin treatment of newborn piglets on the prevalence of hernias and abscesses, growth and ampicillin resistance of intestinal coliform bacteria in weaned pigs

This study investigated the effects of a single amoxicillin treatment of newborn piglets on the prevalence of hernias and abscesses until the age of nine weeks. We also studied whether the treatment was associated with growth and mortality, the need for treatment of other diseases, the proportions of ampicillin resistant coliforms and antimicrobial resistance patterns of intestinal Escherichia coli (E. coli). A total of 7156 piglets, from approximately 480 litters, were divided into two treatment groups: ANT (N = 3661) and CON (N = 3495), where piglets were treated with or without a single intramuscular injection of 75 mg amoxicillin one day after birth, respectively. The umbilical and inguinal areas of weaned pigs were palpated at four and nine weeks of age. At the same time, altogether 124 pigs with hernias or abscesses and 820 non -defective pigs from three pens per batch were weighed individually. Mortality and the need to treat piglets for other diseases were recorded. Piglet faecal samples were collected from three areas of the floors of each pen at four weeks of age. The prevalence of umbilical hernias or abscesses did not differ between the groups at four weeks of age, but it was higher in the CON group than in the ANT group at nine weeks of age (2.3% vs. 0.7%, PPeer reviewe

Antimicrobial Resistance Of Escherichia Coli Isolates In Pig Farm Workers, Normal And Diarrhoeic Pigs

The enumeration of coliforms in faeces can be per formed by both the spread plate method or Most Probable Number ( MPN ) techniques , although MPN total coliform counts are significantly higher ( P<0.05 ) . In so lid agar media enumeration , MacConkey , Desoxycholate , Eosin-Methylene Blue and ENDO agars are suitable media for the enumeration of coliforms . The correlation coefficients of counts among media and technique is high . The mean colony forming unit ( CFU ) counts per gram for coliform in faeces varied from 2 . 6-6 . 4 X 107 and 1 . 8-2 . 7 X 108 for the pigs and form workers tested respectively . Random identification of 291 colonies on MacConkey agar on the basis of frequency of occurrence of numbers of lactose and nonlactose fermenters yielded 94 . 2 % Escherichia coli (E.coli).The other genera isolated includes Enterobacter , Klebsiella , Edwarsiella , Citrobacter and Serratia . About 8.2 % and 29.6 % of the E. coli isolates were non-lactose fermenters on MacConkey agar and did not show the characteristic green metallic sheen on Eosin- Methylene Blue agar respectively