HISTOLOGICAL CHANGES IN VEINED RAPA WHELK MUSCLES (RAPANA VENOSA) AFTER FROZEN STORAGЕ

PURPOSE: The objective of this study was to establish the effect of freezing on the histological structure of veined rapa whelk (Rapana venosa). METHODS: Two hundred veined rapa whelks were collected from the Bulgarian Black Sea coast. Forty veined rapa whelks were subjected to histological analysis in the fresh state, while the remaining 160 veined rapa whelks were divided into 4 groups and frozen in a conventional freezer at -18ºС for 3, 6, 9 and 12 months, respectively. RESULTS: The histological assessment revealed irreversible damages in the entire structure. The observed changes were the smallest after 3 months and the greatest after 12 months of frozen storage. CONCLUSIONS: The histological finding can be used to distinguish fresh from frozen and thawed veined rapa whelks when making an official control

An Authentication Survey on Retail Seafood Products Sold on the Bulgarian Market Underlines the Need for Upgrading the Traceability System

Economically motivated or accidental species substitutions lead to economic and potential health damage to consumers with a loss of confidence in the fishery supply chain. In the present study, a three-year survey on 199 retail seafood products sold on the Bulgarian market was addressed to assess: (1) product authenticity by molecular identification; (2) trade name compliance to the list of official trade names accepted in the territory; (3) adherence of the list in force to the market supply. DNA barcoding on mitochondrial and nuclear genes was applied for the identification of whitefish (WF), crustaceans (C) and mollusks (cephalopods-MC; gastropods-MG; bivalves-MB) except for Mytilus sp. products for which the analysis was conducted with a previously validated RFLP PCR protocol. Identification at the species level was obtained for 94.5% of the products. Failures in species allocation were reconducted due to low resolution and reliability or the absence of reference sequences. The study highlighted an overall mislabeling rate of 11%. WF showed the highest mislabeling rate (14%), followed by MB (12.5%), MC (10%) and C (7.9%). This evidence emphasized the use of DNA-based methods as tools for seafood authentication. The presence of non-compliant trade names and the ineffectiveness of the list to describe the market species varieties attested to the need to improve seafood labeling and traceability at the national level

IN VITRO ANTIBACTERIAL ACTIVITY OF ROYAL GELLY AGAINST PATHOGEN ESCHERICHIA COLI

In the study was used a pathogen strain of E. coli, caused septicemia for ducks,resistant for different antibacterial agents: Amoxicillin, Lincospectin, Chloramphenicol,Doxycyclin, Enrofl oxacin, Sulfonamides and Trimetoprim. Bacterial suspension of E.coli icontaminated each from test solutions in TSB of royal jelly (n=6), mixes of royaljelly and rape honey, and independent used rape honey (10–45% v/v). Have in mindexactly counts of colonies before and after incubation from each of test substanceswas calculated the percent of reduction up to 30 min, and after incubation (24 hand 48 h). In almost all concentrations of royal jelly (10–45 v/v), were found totalinhibition effect to E. coli. Mixes from royal jelly and rape honey (1:100) possesseda higher antibacterial effect, compared with independent use of rape honey. Up to45% (v/v), rape honey does not cause total antibacterial reduction. Royal jelly andmixes from royal jelly and rape honey have potential as alternative therapeuticsagents against resistant for antibiotics pathogen strains of E. coli

First detection of a colistin-resistant Klebsiella aerogenes isolate from a critically ill patient with septic shock in Bulgaria

Colistin is considered as the last-line antibiotic for the treatment of infections caused by extensively drug-resistant Gram-negative pathogens belonging to the ESKAPE (Enterococcus faecium, Staphylo-coccus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enter-obacter species) group. The present study aimed to explore the colistin resistance mechanisms of a Klebsiella aerogenes (formerly Enterobacter aerogenes) isolate (Kae1177-1bg) obtained from a Bulgarian critically ill patient with septic shock in 2020. Antimicrobial susceptibility testing and whole-genome sequencing using DNA nanoball technology were performed. The resulting read pairs were used for draft genome assembly, MLST analysis and mutation screening in the pmrA/B, phoP/Q, and mgrB genes. Kae1177-1bg demonstrated high-level resistance to colistin, resistance to 3rd generation cepha-losporins and susceptibility to all other antibiotics tested. In our strain a CMY-2-type class C cepha-losporinase was the only beta-lactamase identified. No mobile colistin resistance (mcr) genes were detected. A total of three missense variants in the genes for the two-component PmrA/PmrB system were identified. Two of them were located in the pmrB (pR57K and pN275K) and one in the pmrA gene (pL162M). The pN275K variant emerged as the most likely cause for colistin resistance because it affected a highly conservative position and was the only nonconservative amino acid substitution. In conclusion, to the best of our knowledge, this is the first documented clinical case of a high-level colistin-resistant K. aerogenes in Bulgaria and the first identification of the nonconservative amino acid substitution pN275K worldwide. Colistin-resistant Gram-negative pathogens of ESKAPE group are serious threat to public health and should be subjected to infection control stewardship practices

Food safety knowledge and hygiene practices among veterinary medicine students at Trakia University, Bulgaria

The results from the first survey on food safety knowledge, attitudes and hygiene practices (KAP) among veterinary medicine students in Bulgaria are reported in this study. It was designed and conducted from September to December 2015 using structured questionnaires on food safety knowledge, attitudes and practices. Data were collected from 100 undergraduate veterinary medicine students from the Trakia University, Bulgaria. It was observed that the age and the gender did not affect food safety knowledge, attitudes and practices. There was no significant difference (p > 0.05) on food safety knowledge and practices among students based on the years of study. A high level of food safety knowledge was observed among the participants (85.06%), however, the practice of food safety was above average (65.28%) while attitude toward food safety was high (70%). Although there was a significant awareness of food safety knowledge among respondents, there is a need for improvement on food safety practices, interventions on food safety and foodborne diseases

Beneficial effects of medicinal plants in fish diseases

Fish are constantly in contact with pathogens inhabiting water. High populationdensity as well as poor hydrodynamic conditions and feeding lead to an increased sensitivitytowards infections. In order to prevent major economic losses due to diseases, variousmedications are used for treatment and prevention of infections. The use of antimicrobialdrugs in aquacultures could lead to emergence of resistance in pathogenic microorganisms.Alternatives are being sought over the last few years to replace antibiotics, and medicinalplants are one of available options for this purpose. These plants are rich in secondarymetabolites and phytochemical compounds, which have an effect against viral, bacterial, andparasitic diseases in fish. Their main advantage is their natural origin and most of these plantsdo not represent threat for human health, the fish, and the environment. The goal of this reviewis to present information on the treatment of viral, bacterial, and parasitic diseases in fishthrough medicinal plants, with focus on the mechanisms of action of the identified secondarymetabolites, fractions, or plant extracts

Global Alliance for Chronic Disease researchers' statement on multimorbidity

Comment -No Abstract available