Category Archives: Research

Research – Molecular detection and genotype identification of Toxoplasma gondii in domestic and industrial eggs

Wiley Online 

 

Abstract

Birds are important intermediated hosts of Toxoplasma gondii. Consumption of chicken meat and its infected products is one of the main sources of human infection with T. gondii. However, little information is available about T. gondii infection in egg. In this study, the contamination of industrial and local eggs with Toxoplasma was investigated by PCR method targeting the RE gene in two tropical cities of Iran. Genotypes of T. gondii were determined by PCR‐RFLP method targeting the SAG3 gene. T. gondii DNA was detected in 11% (22/200) of the eggs. Genotyping of 14 T. gondii isolates revealed that all of the isolates were belonged to genotype III of T. gondii. Sequencing of the isolates by the SAG3 gene showed 95%–100% similarity with the T. gondii isolates in GenBank.

Practical applications

The findings of this study suggested that consumption of raw or undercooked eggs might play a role in human infection with Toxoplasma. Hence, consumption of adequately cooked eggs should be considered for prevention of human toxoplasmosis.

Research – Novel Continuous and Manual Sampling Methods for Beef Trim Microbiological Testing

Journal of Food Protection

A sampling method that represents a greater proportion of the beef trimmings in a 900-kg combo bin should improve the current pathogen sampling and detection programs used by fresh beef processors. This study compared two novel, nondestructive sampling methodologies (a continuous sampling device [CSD] and a manual sampling device [MSD]) with the current industry methodologies, the N60 Excision (the “gold standard”) and N60 Plus, for collection of trim samples. Depending on the experiment, samples were analyzed for naturally occurring Escherichia coli O157:H7 or Salmonella, inoculated surrogates, or indicator organisms in multiple plants, on multiple days, across multiple lean percentage mixtures. Experiments 1A and 1B with natural contamination found no E. coli O157:H7 but similar (P > 0.05) prevalence of Salmonella (CSD 9.2% versus N60 Excision 6.0%) and similar (P > 0.05) levels of indicator organisms for CSD compared with both N60 methodologies. In experiments 2 and 3, CSD cloth sampling had the same or higher prevalence of naturally occurring E. coli O157:H7 and E. coli O157:H7 surrogate organisms, as well as similar levels of indicator organisms compared with the N60 methodologies. In experiment 4, MSD cloth sampling detected similar (P > 0.05) prevalence of E. coli O157:H7 surrogate organisms, as well as slightly lower (P < 0.05) levels of indicator organisms compared with N60 Plus. In experiment 5, the MSD found similar (P > 0.05) prevalence of naturally occurring E. coli O157:H7 and the same or slightly higher (P < 0.05) levels of naturally occurring indicator organisms compared with N60 Plus. In experiment 6, the MSD detected the same (P > 0.05) prevalence of naturally occurring Salmonella as did N60 Excision. The results of these experiments collectively demonstrate that sampling beef trim using either the CSD or MSD provides organism recovery that is similar to or better than the N60 Excision or the N60 Plus methodologies.

UK – Publication of survey of antimicrobial resistance in bacteria in chicken and pork

FSA

We have today published the results of a survey we commissioned to assess the amount of antimicrobial resistance (AMR) in bacteria in fresh pork mince and fresh and frozen chicken on sale in shops in the UK. These findings will help to establish a baseline of the occurrence, types and levels of AMR in bacteria found in these UK retail meats which will inform future surveillance on AMR in these foods.

This survey follows on from an authoritative report by a group established by the Advisory Committee on Microbiological Safety of Food (ACMSF) to advise us on research questions and potential approaches to AMR in the food chain.

The survey involved the testing of Campylobacter in chicken samples and Salmonella in pork mince samples for the occurrence of antimicrobial resistant bacteria. The survey also looked for AMR in other bacteria in both types of meat including Enterococci, Klebsiella and Escherichia coli.  Read the final report of the survey.

Research -Don’t kill, but tame the bacteria

All About Feed

Producing broiler meat with the label ‘no antibiotics ever’ is becoming a common thing in the US. In the meantime, the poultry sector fears that this leads to a less efficient system, in which it is harder to control major poultry diseases. Luckily, a new set of savvy feed additives that keep bad bacteria under control is on its way.

Salmonella Campylobacter

Poultry production under the philosophy ‘no antibiotics ever’ (NAE), is spreading like a wild fire in the US and also in some other parts of the world. Although this sounds like a good development, and it is, it also comes with challenges, both from a nutritional standpoint as well as keeping the margins and being able to sell the products. At a recent first-annual summer international poultry symposium, organised by Amlan International, the challenges and solutions for poultry producers to produce under antibiotic free systems were discussed in further detail.

Research -Antibacterial Effect of Essential Oils against Spoilage Bacteria from Vacuum-Packed Cooked Cured Sausages

Journal of Food Protection

Nonfermented sausages, which have a pH of around 6.0, a low salt concentration, and high moisture with a water activity higher than 0.95, are highly perishable. In this study, culture-dependent techniques and 16S rDNA approaches were used to identify the presumptive spoilage lactic acid bacteria (LAB) in sliced vacuum-packed cooked sausage during storage at 4°C. The antibacterial properties of essential oils (EOs) from the medicinal plants Carum carvi, Cinnamomum zeylanicum, Curcuma longa, Citrus medica, and Eugenia caryophyllata against isolated LAB were also investigated. A total of 106 colonies were obtained on de Man Rogosa Sharpe medium after storage of sausages samples, and 16 isolates were identified from conventional morphological analysis of the bacterial populations. DNA extraction and 16S rDNA analysis indicated that Lactobacillus curvatus, Weissella viridescens, Leuconostoc mesenteroides, Enterococcus faecium, Lactobacillus reuteri, Lactobacillus dextrinicus, Lactobacillus sakei, and Pediococcus dextrinicus were the main spoilage LAB. The antibacterial properties of EOs against isolated LAB were indicated by inhibition zones on culture plates of 7.8 to 31 mm, depending on the susceptibility of the tested LAB strain. The MICs and MBCs of five EOs were determined. The most effective EO against the LAB was C. zeylanicum followed by C. carvi and C. medica, and the least effective EO was C. longa. The EO from C. zeylanicum had the highest antimicrobial activity (lowest MICs) against LAB, with EO MICs of 4.66 to 5.33 μL/mL. The most susceptible isolate was L. mesenteroides, with a MIC of 4.66 μL/mL for the C. zeylanicum EO. These data indicate that the EO from C. zeylanicum could be used as a natural preservative for vacuum-packed emulsion‐type sausage.

Research – Antibacterial Effect of Essential Oils against Spoilage Bacteria from Vacuum-Packed Cooked Cured Sausages

Journal of Food Protection

Nonfermented sausages, which have a pH of around 6.0, a low salt concentration, and high moisture with a water activity higher than 0.95, are highly perishable. In this study, culture-dependent techniques and 16S rDNA approaches were used to identify the presumptive spoilage lactic acid bacteria (LAB) in sliced vacuum-packed cooked sausage during storage at 4°C. The antibacterial properties of essential oils (EOs) from the medicinal plants Carum carvi, Cinnamomum zeylanicum, Curcuma longa, Citrus medica, and Eugenia caryophyllata against isolated LAB were also investigated. A total of 106 colonies were obtained on de Man Rogosa Sharpe medium after storage of sausages samples, and 16 isolates were identified from conventional morphological analysis of the bacterial populations. DNA extraction and 16S rDNA analysis indicated that Lactobacillus curvatus, Weissella viridescens, Leuconostoc mesenteroides, Enterococcus faecium, Lactobacillus reuteri, Lactobacillus dextrinicus, Lactobacillus sakei, and Pediococcus dextrinicus were the main spoilage LAB. The antibacterial properties of EOs against isolated LAB were indicated by inhibition zones on culture plates of 7.8 to 31 mm, depending on the susceptibility of the tested LAB strain. The MICs and MBCs of five EOs were determined. The most effective EO against the LAB was C. zeylanicum followed by C. carvi and C. medica, and the least effective EO was C. longa. The EO from C. zeylanicum had the highest antimicrobial activity (lowest MICs) against LAB, with EO MICs of 4.66 to 5.33 μL/mL. The most susceptible isolate was L. mesenteroides, with a MIC of 4.66 μL/mL for the C. zeylanicum EO. These data indicate that the EO from C. zeylanicum could be used as a natural preservative for vacuum-packed emulsion‐type sausage.

Research – Crowdsourcing friendly bacteria helps superbug cause infection

Science Daily Staphylococcus

Antimicrobial resistant pathogens crowdsource friendly bacteria to survive in immune cells and cause disease, a new study by the University of Sheffield has revealed.


Scientists have discovered the human pathogen Staphylococcus aureus (S.aureus), uses benign bacteria present in the skin to initiate infection.

Known commonly as its infamous antimicrobial resistant form MRSA (meticillin-resistant Staphylococcus aureus), the ground-breaking research discovered that by using the other bacteria present on the skin, the pathogen can survive the mechanisms our immune system deploys to destroy it.

The findings, published today (16 July 2018) in Nature Microbiology, give scientists a new insight into the mechanisms of the so-called superbug, which is hard to treat due to its resistance to several widely used antibiotics.