Transmission of common foodborne viruses by meat products

The most common foodborne viruses are single stranded RNA viruses which are adaptable and extremely resistant to environmental stress factors. Usual routes of food contamination are via stool material by persons shedding intestinal virus, or by saliva aerosols generated by shedding persons when coughing. Contamination of meat by animal viruses occurs when good hygienic and manufacturing practice fails. Once within food, viruses cannot replicate since they require living cells for this; hence food is not sensorily altered. Preventive measures in meat processing against pathogenic bacteria frequently have poor antiviral performance, while diagnostic techniques for viruses remain problematic

Nova istraživanja virulentnosti enterohemoragičnih Esherichia coli u hrani

Most of the genes recently found in pathogenic E. coli encode various factors which directly determine their virulence and pathotype. Two main virulence factors characteristic for enterohemorrhagic E. coli(EHEC) are attaching/effacing lesions and Stx1/Stx2 toxins. Genes responsible for expression of aforementioned virulence factors are heavily regulated by environmental conditions. Low iron concentration induces massive expression of stx1 gene and subsequent toxin synthesis. Stress response of EHEC to starvation, acid challenge, cold shock and osmotic changes which damage DNA, induce 'SOS' response. This response mediated by Rec A protein not only repairs damaged DNA fragments but also induces conversion of lysogenic bacteriophage lifecycle to lytic phase followed by intensive expression of stx2 genes. Bacterial stress adaptation of E. coli to novel technologies and the potential for stress-associated enhanced virulence need to be addressed in more detail to prevent potential risk of disease. An increased understanding of expression of virulence-associated genes will provide information for control of pathogens and increase microbial safety of foods.Većina gena koji su poslednjih godina utvrđeni kod patogenih E. coli kodiraju različite faktore koji direktno utiču na njihovu virulentnost i pripadnost određenom patotipu. Dva glavna faktora virulencije kod enterohemoragičnih E. coli (EHEC)su attaching/effacing lezije Stx1/Stx2 toksini. Geni odgovorni za ekspresiju pomenutih faktora virulencije pod jakim su uticajem uslova sredine. Niska koncentracija gvožđa indukuje jaku ekspresiju stx1 gena i posledičnu sintezu velike količine Stx1 toksina. Stresni odgovor EHEC na manjak hranljivih supstanci, povećanje kiselosti sredine, izloženost hladnoći kao i na promene osmolarnosti, koji oštećuju DNK, indukuje 'SOS' odgovor. 'SOS' reakcija posredovana Rec A proteinom ne samo da popravlja oštećene fragmente DNK molekula, već i pokreće mehanizam konverzije bakteriofaga integrisanog u hromozom E. coli iz lizogene faze u litički ciklus tokom koga dolazi do intenzivne ekspresije stx2 gena. Da bi se preventirao potencijalni rizik nastanka bolesti, neophodno je detaljno proučavati prilagođavanje E. coli novim tehnologijama pripreme i konzervacije hrane i potencijal za stres-indukovanu virulenciju. Dobro poznavanje ekspresije gena odgovornih za virulenciju obezbediće informacije neophodne za kontrolu patogena i povećaće mikrobiološku bezbednost hrane

The influence of dietary composition on food preference in Sharplanina Shepherd puppies

Pet food manufacturers aim to balance the palatability with the nutritional value of their products. Ensuring that young canines receive the best nourishment is crucial, while also promoting long-lasting engagement and satisfaction during mealtime. The study aimed to investigate if the nutritional content of food can affect food preferences in 2-month-old Sharplanina shepherd dogs and the development of neophobia when introduced to a new diet. Three different dietary plans were tested, each with varying percentages of an imal-derived proteins (97% in A, 77% in B, and 94% in C). Observations of behavior were documented on camera at the beginning and end of a 10-day feeding cycle. The observations were made during the scheduled feeding times of 7 a.m., noon, and 5 p.m. According to the study, puppies showed neophobic behavior when a new diet was introduced. The puppies displayed a notable decrease in meal rate of sumption, heightened distraction during diet consumption, and increased hesitation on the first day of each new diet, specifically on day 9 and day 10. Post-consumption interest peaked significantly on day 9 and day 10, particularly when dogs consumed diet C. Through the study, it was observed that Diet C had an impact on the puppies’ feed preferences, indicating a possible link between the diet’s nutritional content and their food preferences. Based on the study results, it appears that puppies need at least 9 days to reduce phobia and adapt to new food flavors and feeding schedules

Molecular typing, pathogenicity factor genes and antimicrobial susceptibility of vancomycin resistant enterococci in Belgrade, Serbia

In this study the distribution of species and antimicrobial resistance among vancomycin resistant enterococci (VRE) recovered from clinical specimens obtained from five hospitals in Belgrade was analyzed. Strains were further characterized by pulsed-field gel electrophoresis (PFGE). Polymerase chain reaction (PCR) was used to investigate the presence of vanA and vanB genes and pathogenicity factor genes. Identification of 194 VRE isolates revealed 154 Enterococcus faecium, 21 Enterococcus faecalis, 10 Enterococcus raffinosus and 9 Enterococcus gallinarum. This study revealed existence of 8 major clones of VRE. PCR determined vanA gene to be present in all of the VRE studied. Esp and hyl genes were present in 29.22% and 27.92% of E. faecium, respectively, and in 76.19% and 0 of E. faecalis, respectively. Esp and hyl genes were not found more frequently in members of predominant clones of E. faecium than in single isolates; nor was their presence connected to invasiveness

Antimicrobial resistance among Salmonella enterica serovar Infantis from broiler carcasses in Serbia

This study aimed to investigate antimicrobial resistance of Salmonella Infantis isolates from poultry carcasses in Serbia. A total of 48 Salmonella isolates were examined for antimicrobial resistance. A panel of 10 antibiotics was selected for testing. Isolates showed resistance to sulfamethoxazole, ceftazidime and cefotaxime (100%). However, the highest number of Salmonella Infantis isolates were sensitive to chloramphenicol. The usage of antibiotics in food producing animals could result in antimicrobial resistance pathogenic bacteria especially Salmonella spp. in poultry, which may be transmitted to humans through the food chain and increase risk of treatment failures

Analiza kretanja trenda pojave trihineloze svinja pre i posle sistematske deratizacije

In the territory of Serbia, the occurrence of trichinellosis in domestic pigs has been present for a long number of years. In a ten-year period, a total of 1,224 pigs were registered in one populated area with the diagnosis of a larval form of the parasite T.spiralis. In the middle of the period of examination, a systematic deratization of the complete settlement was carried out, the neighboring garbage dumps, and a pit grave. The systematic deratization was performed using the preparation Brodisan. This preparation is a liquid concentrate for the preparation of bait with 0.25% bromadiolone (3-(3-/-bromobiphenyl-4- il/-3-hydroxy-1-phenylpropyl)-4-hydroxycoumarin). The total used quantity of bait for one systematic deratization in this populated area was 4,840 kg. Analyzing the tendency of the incidence of positive pigs in the period before the systematic deratization, we established that the average annual increase was around 70 pigs (b=69.30). The best adapted line of movement of the number of positive pigs was a third degree polynomial (Ŷ=185.20- 304.10x + 147.10x2-16.75x3), because its correlation coefficient is the biggest (rxy=0.96). The analysis of the trend in the number of infected pigs after the systematic deratization was performed in the examined area, it was established on the grounds of the negative parameter b of the straight line trend, that the average annual reduction in the number of infected pigs was 39.80. The tendency of a reduction of the number of infected pigs following the systematic deratization is best described by a second degree polynomial (Ŷ=307.2- 109.23x + 11.57x2) because its correlation coefficient is rxy=0.98.Na prostorima Srbije pojava tihineloze kod domaćih svinja zapaža se duži niz godina. U desetogodišnjem periodu u jednom naseljenom mestu evidentirano je ukupno 1.224 grla svinja kod kojih je dijagnostikovan larveni oblik parazita T. spiralis. Na polovini ispitivanog perioda izvedena je sistematska deratizacija kompletnog naselja, okolnih deponija smeća i jame grobnice. Sistematska deratizacija u ispitivanom naseljenom mestu obavljena je preparatom Brodisan. Ovaj preparat je tečni koncentrat za pripremu mamaka sa 0,25 % bromadiolona (3-(3- /4-brombifenil-4-il/-3-hidroksi-1-fenilpropil)-4-hidroksikumarin). Ukupna upotrebljena količina mamka za jednu sistematsku deratizaciju u ovom naseljenom mestu je 4.840 kg. Analizirajući tendenciju pojave pozitivnih grla svinja u periodu pre sistematske deratizacije ustanovili smo da je prosečno godišnje povećanje iznosilo oko 70 svinja (b=69,30). Najbolje prilagođena linija kretanja broja pozitivnih svinja je polinom trećeg stepena (Ŷ=185,20-304,10x + 147,10x2-16,75x3), jer je njegov koeficijent korelacije najveći (rxy=0,96). Analizom trenda broja inficiranih svinja nakon izvedene sistematske deratizacije ispitivanog naseljenog mesta ustanovljeno je, na osnovu negativnog parametra b iz pravolinijskog trenda, da prosečno godišnje smanjenje broja inficiranih svinja iznosi 39,80. Tendenciju kretanja smanjenja broja inficiranih svinja posle sistematske deratizacije najbolje opisuje polinom drugog stepena (Ŷ=307,2-109,23x+11,57x2) jer je njegov koeficijent korelacije rxy=0,98

The common foodborne viruses: A review

Transmission pathways of foodborne viruses include contamination of food by infected food handlers, by contamination of food during the production process and by consumption of products of animal origin harbouring a zoonotic virus. Viral foodborne illnesses, which have become a significant cause of all reported foodborne illnesses in recent years and considered as an emerging risk in veterinary public health. Microbiological genomics studies discovered that Noroviruses and hepatitis A viruses were primarily associated with food-handler transmission and sewage-contaminated foods. In contrast, hepatitis E was associated with consumption of raw or undercooked meat of pig or wild animals. In order to facilitate source attribution and identify risk prevention measures, Routine harmonized surveillance of viral outbreaks, and surveillance of virus occurrence in food commodities, in combination with systematic strain typing, and joint expertise from veterinary, food, and clinical microbiologists would be recommended

Determination of the economic effects in intesive production of piglets

Critical indicators of intensive production in hog raising are continuity of production, high level of produced series-tours, application of the most contemporary technological achievements without any turnover of capital, high merchandise turnover, and intensive usage of the reproduction potential of breeding material. Production of piglets represents one of the most essential phases in the production of pork meat. In spite of genetic factors, duration of interval wean-conception is one of the basic factors in determination of bringing forth indexes and number of piglets per litter. In order to recognize production costs of piglets completely we found nutrition costs for piglets and sows represent 61%, while other costs such as personal incomes, veterinary services, water, energy, losses, and amortization represent 39% of total costs. On the basis of cost price per feeding day of a sow and the number of piglets per litter, production costs of piglets older than 28 days with an average body weight of 7 kg were determined. Price cost per piglet after weaning, with 7 kg average body weight, and 146 days of reproduction process accounts for 21,78 EUR if there are 10 piglets in a litter. If the reproductive cycle would last exactly the same and if successful conception would be achieved 25 days after weaning, production cost per piglet would be 23,79 EUR

Production characteristics and safety parameters of Sremska ham

Sremska ham is a traditional dry-cured meat product manufactured by salting, smoking and drying pork hams in a mainly natural environment. The traditional production process of cured ham in Srem region (Vojvodina, Serbia) is standardized and adjusted to good manufacturing and good hygiene practice procedures. Quality parameters for Sremska ham are well defined, and include mass, ripening time, flavor etc., in order to attain product with standardized and well recognized quality. Sremska ham is produced from pork meat obtained from healthy, well rested, late maturing animals, mass 120 to 150kg. Hams are dry salted and the process itself lasts for 4 to 6 weeks depending on the ham mass. Meat selection based on pH is of great importance in order to achieve proper salt diffusion in ham. Salt diffusion occurs in the desired manner only if the pH of the meat is less than 6.0. Biohazards which can occur during the production of Sremska ham are Clostridium botulinum spores, if conditions for their germination and toxin production exist, mycotoxin producing moulds, and infestation by insect larvae. Those hazards can be eliminated or reduced by maintaining a low temperature during the critical production stages and ensuring sufficient salt content to inhibit C. botulinum growth. Moulds and insects are controlled by maintaining appropriate storage conditions. The manufacturing process of Sremska ham should be based on HACCP principles, while preserving the traditionality of the process

Occurrence of Listeria monocytogenes in a Serbian salmon and seafood processing line during 2013

The objective of this study was to examine the occurrence of L. monocytogenes in a selected fish and seafood processing line. Results showed that during 2013, 12.4 %, 8.3 % and 2.3 % of fish, seafood salads and environmental swabs were positive for L. monocytogenes. All positive food samples showed a contamination level below 100 CFU/g. Environmental swabs from surface of slicing and trimming tables, slicing machines, fish filleting and trimming knives, belt glazer and working table were positive for L. monocytogenes. Therefore, strict attention must be paid to cleaning and disinfection to control the level of L. monocytogenes