Marian Mihaiu

Antibiotic susceptibility and prevalence of foodborne pathogens in poultry meat in Romania.

INTRODUCTION The occurrence of pathogenic strains in poultry meat is of growing concern in Romania. Another problem found on a global level is the continuous increase of antimicrobial resistance in bacteria isolated from food. This study aimed to evaluate the prevalence of pathogenic bacteria in poultry carcasses obtained in Romania in 2012-2013 and to reveal the most prevalent patterns of antimicrobial resistance in the isolated strains. METHODOLOGY A total of 144 broiler chicken carcasses were evaluated according to classical microbiological methods. The DNA was extracted from the bacterial colonies and the resistance genes were identified by PCR. RESULTS In 2012, 47.2% of the samples revealed at least one of the following bacteria: Campylobacter jejuni (9.72%; n = 7), Salmonella enterica serotype Enteritidis (4.17%; n = 3), Listeria monocytogenes (15.28%; n = 11), and Escherichia coli (16.67%; n = 12). In 2013, the number of positive samples of pathogenic bacteria decreased, although Campylobacter jejuni was isolated in a higher percentage (20.8% vs. 9.72%). The percentage of multidrug-resistant (MDR) bacteria was high (23%); the most prevalent pattern included resistance to tetracycline, sulfonamides, and quinolones/fluoroquinolones. All the resistant Salmonella and E. coli strains were tested for the presence of characteristic resistance genes (Kn, bla(TEM), tetA, tetB, tetG, DfrIa, aadA1a, Sul) and revealed that these isolates represent an important reservoir in the spread of this phenomenon. CONCLUSIONS Our findings suggest that Romania urgently needs an integrated surveillance system within the entire chain, for drug-resistant pathogens isolated from poultry meat.

First study of Salmonella in meat in Romania.

INTRODUCTION The increasing antimicrobial resistance of Salmonella isolates is of major public health concern, but information regarding these aspects is still lacking in Romania. This study focused on a detailed and accurate investigation concerning prevalence, serotypes, and antimicrobial resistance patterns of Salmonella strains, isolated from pork and chicken meat, collected from all regions of Romania in 2011. METHODOLOGY The research was conducted on 650 samples of chicken and pork meat collected from production units and retail markets located in various regions of Romania. A total of 149 Salmonella isolates were recovered (22.92%), serotyped, confirmed by PCR, and further tested for antimicrobial susceptibility. RESULTS Thirteen Salmonella serovars were identified; predominant serovars included Infantis, Typhimurium, Derby and Colindale. Multiple resistance was found in 83.22% (n = 124) of the isolates. The isolates were frequently resistant to tetracycline (80.53%), streptomycin (81.21%), sulfamethoxazole (87.25%), nalidixic acid (65.10%), and ciprofloxacin (42.95%). Additionally, a markedly lower resistance rate was observed for ampicillin (20.81%), chloramphenicol (16.78%), and ceftazidime (11.41%). Among 137 resistant Salmonella isolates, 35 different resistance patterns were found. CONCLUSION A high prevalence of Salmonella spp. and a relatively high resistance rate to multiple antimicrobials was found. This data indicates that chicken and pork meat could constitute a source of human exposure to multidrug-resistant Salmonella and therefore could be considered a potential vehicle of resistant Salmonella foodborne diseases. Further actions are needed to succesfully implement a national surveillance program for better monitoring of these resistant pathogens.

First description of plasmid-mediated quinolone resistance determinants and β-lactamase encoding genes in non-typhoidal Salmonella isolated from humans, one companion animal and food in Romania

BackgroundGastroenteritis attributable to Salmonella enterica and the continuous increase in antimicrobial resistance of this gut pathogen, which compromises the use of previously effective treatments, is of great concern for public health. This study was conducted in order to investigate the presence of plasmid-mediated quinolone resistance (PMQR) determinants and β-lactamase-encoding genes, in S.enterica, isolated from humans, one companion animal and food. Moreover, the study aimed to identify potential vehicles of transmission of resistant strains to humans, with focus on food products (meat).MethodsA total of 20 S. enterica isolates recovered from food (chicken and pork meat), one companion animal and humans (stool samples), were examined for their serotype, antimicrobial susceptibility and the presence of PMQR and β-lactamase-encoding genes. Moreover, the genetic relatedness of nine Salmonella Infantis and ten Salmonella Enteritidis isolates was analyzed by pulsed-field gel electrophoresis (PFGE).ResultsAmong all isolates, 15 (75%) were multidrug-resistant (MDR) and the majority of them proved to be resistant to nalidixic acid and fluoroquinolones (FQs) (ciprofloxacin and levofloxacin). Twelve isolates (60%) harboured at least one PMQR gene [qnrA, qnrB, qnrS, aac (6′)-Ib-cr or qepA] while seven isolates (35%) carried at least one β-lactamase-encoding gene (blaTEM, blaPSE-1, blaSHV or blaCTX-M). Moreover, two or more PMQR or β-lactamase-encoding genes co-existed in a single S.enterica isolate. A number of nine Salmonella Infantis, as well as the majority of Salmonella Enteritidis isolates analyzed by PFGE proved to be closely related.ConclusionsThe study demonstrated the co-existence of PMQR and β-lactamase-encoding genes among the Salmonella isolates recovered and confirmed that multiple mechanisms might be involved in the acquisition and spread of resistance determinants. The close genetic relatedness between the clinical and foodborne S. enterica isolates, suggested that chicken meat might be a possible cause of human salmonellosis in our country, during the study period. Results of this study might improve understanding of the antimicrobial resistance mechanisms and transmission dynamics of Salmonella spp. Here, we report for the first time the presence of PMQR and β-lactamase-encoding genes in S. enterica isolates, recovered from humans, one companion animal and food, in Romania.

Influence of DGAT1 K232A Polymorphism on Milk Fat Percentage and Fatty Acid Profiles in Romanian Holstein Cattle

Milk and dairy products are considered the main sources of saturated fatty acids, which are a valuable source of nutrients in the human diet. Fat composition can be adjusted through guided nutrition of dairy animals but also through selective breeding. Recently, a dinucleotide substitution located in the exon 8 of the gene coding for acyl CoA: diacylglycerol acyltransferase 1 (DGAT1), that alters the amino acid sequence from a lysine to an alanine (p.Lys232Ala) in the mature protein, was shown to have a strong effect on milk fat content in some cattle breeds. Therefore, the objectives of this work were to study the occurrence of the DGAT1 p.Lys232Ala polymorphism in Romanian Holstein cattle and Romanian Buffalo breeds and to further investigate its possible influence on fat percentage and fatty acid profiles. The results obtained in this study show that in Romanian Holstein cattle the K allele is associated with increased fat percentage and higher levels of C16:0 and C18:0 fatty acids. The ratio of saturated fatty acids versus unsaturated fatty acids (SFA/UFA) was also higher in KK homozygous individuals, whereas the fractions of C14:0, unsaturated C18 decreased. The DGAT1 p.Lys232Ala polymorphism revealed a high genetic variance for fat percentage, unsaturated C18, C16:0, and SFA/UFA. Although the effect of this polymorphism was not so evident for short chain fatty acids such as C4:0–C8:0, it was significant for C14:0 fatty acids. We concluded that selective breeding of carriers of the A allele in Romanian Holsteins can contribute to improvement in unsaturated fatty acids content of milk. However, in buffalo, the lack of the A allele makes selection inapplicable because only the K allele, associated with higher saturated fatty acids contents in milk, was identified.

Congenital diaphragmatic hernia with concurrent aplasia of the pericardium in a foal

BackgroundIn veterinary medicine congenital abnormalities of the diaphragm and pericardium are rare, idiopathic malformations, being reported mainly in dogs. This report documents an unusual case of developmental defects in a foal consisting of diaphragmatic hernia concurrent with pericardial aplasia.Case presentationFollowing a normal delivery, a full term, female Friesian stillborn foal with the placenta was presented for necropsy. External morphological examination indicated a normally developed foal. At necropsy, a large oval defect (approximately 20 × 15 cm in size) was observed in the left-dorsal side of the diaphragm (left lumbocostal triangle). This defect allowed the intestinal loops, spleen and partially the liver to translocate into the thorax. The loops of the left ascending colon, including the pelvic flexure and partially the small intestine covered the cranial and dorsal posterior parts of the heart due to the complete absence of the left pericardium. The remaining pericardium presented as a white, semi-transparent strip, partially covering the right side of the heart. The left lung and the main bronchus were severely hypoplastic to approximately one-fifth the size of their right homologue. The intermediate part of the liver, containing mainly the enlarged quadrate lobe was translocated in the thorax, severely enlarged and showed marked fibrosis. Histologically in the herniated lobes we diagnosed hepatic chronic passive congestion, telangiectasia and medial hypertrophy of blood vessels.ConclusionConcomitant malformation involving diaphragmatic hernia and pericardial aplasia in horses have not been previously reported. Moreover, this is the first case describing pericardial aplasia in horse.

Concerning Increase in Antimicrobial Resistance in Shiga Toxin-Producing Escherichia coli Isolated from Young Animals during 1980–2016

This study was conducted in order to assess the antimicrobial resistance patterns of E. coli isolated from young animals affected between 1980 and 2016. The selected isolates for this study (n=175) carried stx1/stx2 genes and the most prevalent type of pathogenic E. coli found belonged to serogroup O101, antigen (K99)–F41 positive. All STEC-positive isolates were tested for susceptibility to 11 antimicrobials. Multidrug resistance (MDR) increased from 11% during the 1980s to 40% between 2000 and 2016. Resistance to tetracycline and streptomycin was the most frequent co-resistance phenotype (37%). Co-resistance to tetracycline and sulfonamide was found in 21% of E. coli isolates, while the MDR pattern to tetracycline, sulfonamide, and streptomycin was observed in 12% of the strains tested. Only 8% of isolates were co-resistant to tetracycline, ampicillin, streptomycin, and sulfonamide. The most common resistance genes found were those encoding for tetracycline, sulphonamides, and streptomycin, with 54% (n=95) of the tested isolates containing at least one of the genes encoding tetracycline resistance. A total of 87% of E. coli that tested positive for tetracycline (tetA, tetB, and tetC) and sulphonamide (sul1) resistance genes were isolated between 2000 and 2016. A large number of isolates (n=21) carried int1 and a nucleotide sequence analysis revealed that all class 1 integron gene cassettes carried sul1, tet, and dfrA1 resistance genes. An increase was observed in the level of resistance to antimicrobials in Romania, highlighting the urgent need for a surveillance and prevention system for antimicrobial resistance in livestock in Eastern Europe.

Human Health Risks Associated with Chemical and Mycrobiological Contaminants in Fish - A Mini Review

Abstract Fish meat consumption has gained a lot of popularity in Europe in the last years. It is considered to be a great alternative for red meat because it provides large amounts of Omega-3 fatty acids and vitamin D. These components lower the risk of cardiovascular disease, reduce the risk of autoimmune diseases, are essential for growth and development, can contribute to mood elevation and can prevent cognitive decline, and eye disease. Unfortunately the benefits can sometimes be accompanied by a risk associated with chemical and microbiological contaminants. The aim of this paper is to review some recently published studies concerning the groups of chemical compounds and bacteria found in fish meat, which can have negative effects on human health. In order to raise awareness, aspects related to dangerous persistent organic pollutants and zoonotic bacteria are described. The frequency of encountering them is discussed, the ways in which they can reach the human body are specified and a critical comparison of their consequences is performed.

Geographical origin and species differentiation of Transylvanian cheese. Comparative study of isotopic and elemental profiling vs. DNA results

The present study proposed the cheese differentiation, according to geographical production area and with respect to species (cow, sheep) of two traditional cheese specialties, (salty and ripened), produced in Transylvania, Romania. For this purpose, the elemental profile and carbon isotopic ratios (13C/12C) of cheese and extracted casein were corroborated through statistic supervised techniques to get the best discrimination markers. The manganese content, along with Rare Earth Elements (REE) concentrations, proved to be very powerful predictors, for the traditional salted cheese mainly, due to the direct influence of the local salted water. Despite that proposed techniques are not acknowledged methods for species differentiation, this approach allowed a successful discrimination of the animal species that produced the raw materials for cheese manufacturing (milk). The results generated by the developed chemometric model, for species differentiation, were compared with those obtained using Isoelectric focusing (IEF) and DNA tests. The proposed association of isotopic and elemental markers allowed a differentiation better than 92% for geographical provenance, of each investigated cheese specialties while, for species discrimination (cow vs. sheep) a percentage of 100% was obtained.

Microbiological Assessment of Raw Meat Used in Fast-Food Products Sold for Public Consumption

Raw meat contains sufficient nutrients to support microbial growth and because of that the proper surveillance of the meat products destined for public consumption is mandatory. The purpose of this study was to conduct a microbiological risk assessment regarding the safety of pork, chicken and beef meat products found in fast –food units from Transylvania area. One hundred and seventy samples of raw meat(n=35) and fried foods made of pork(n=39), chicken(n=45)and beef products(n=51) were purchased randomly from 5 different fast-food units located in the study area.The determination performed in order to assess the safety was the total number of Enterobacteriaceae, evaluation of toxigenic E. coli and Salmonella spp. presence, which is also the parameter requested by the current regulation. The levels of contamination with Enterobacteriaceae that exceeded the current legislation limit were 6/39 (15%), 6/45 (13%) and 5/51 (9%) in cooked pork, chicken and respectively beef meat. Given the similar rate of contaminations among these three categories of food there were no statistical differences noticed (p>0.05). Results showed that in 35 of 170 (20%) collected food samples were found total Enterobacteriaceae count over 3 log CFU/g and 12 of 170 (7%) were found with coliform bacteria. Raw meat destined for fast-food industry can represent a risk for public health if hygiene and refrigerating conditions are not properly monitored.

Aspects Regarding the Evaluation of the Microbiological Status of the Minced Meat Products From a Processing Unit

Minced meat and processed meat are raw products that are very susceptible to all microbiological factors to which they are exposed. In this sudty, 108 samples were analyzed during two years. The results have revaled the contamination following the human factor (1 case of Salmonella contamination at processed meat), respectivelly the high bacteria load in minced meat revealed by the Total Germ Count (TGC) and Escherichia coli values. These results were due to the semi-automatic packaging process (samples 1 - 42) and their significant decrease after the introduction of an automatic packaging system (samples 43-58). The conclusion of our study was that the packaging technology which limits the human contact and the environment surfaces contact ensures a safer product for the consumer.