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Showing 29 results for Salmon


Volume 2, Issue 1 (3-2014)
Abstract

The effects of fish weight on salinity tolerance were studied in Caspian salmon (Salmo trutta caspius) parr. 180 fish (all with 2 years old but with three weights; 5, 15, 25g) were selected and they reared in freshwater (FW) and brackish water (BW; 13ppt salinity) for 10 days. The mRNA expression of two α-subunit isoforms of Na+, K+-ATPase (α1a and α1b) and NKCC co-transporters were studied in their gill tissue. In all three weight groups, the mRNA levels for the α1a isoforms decreased following BW exposure, whereas α1b levels significantly increased in 15g and 25g groups. In addition, NKCC gene expression were significantly higher in the groups of BW than FW in 15g and 25g weights (P<0.05). The reciprocal expression of Na+, K+-ATPase isoforms (α1a and α1b) during salinity acclimation suggests that they may have different roles in the gill of FW and BW fishes; ion uptake in FW and ion secretion in BW. In conclusion, in the Caspian salmon, between parrs with the same age, the group with the weight of 15g possesses better compatibility with BW than to other groups.  After reaching to 25g, fish passed smoltification and they became more compatible with the FW environment and maybe lost its osmoregulation ability in saline or brackish water.

Volume 2, Issue 3 (7-2016)
Abstract

Background: Salmonella enterica serovar typhi (S. typhi) the cause of the acute febrile disease typhoid fever is the major public health problem in developing countries. Asymptomatic carriers are the main sources of typhoid. The aim of this study was to investigate methods for isolation and identification of S. typhi in asymptomatic carriers.
Materials and Methods: Two hundred stool samples were collected from foodstuff workers and distributors. Then culture characterization, biochemical tests, and nested-PCR were done.
Results: One hundred and seventy-one (85%) of the total cases were male and the mean age of cases was 35 years. Stool culture yielded bacterial colonies consistent with fecal flora but did not yield S. typhi. In nested PCR technique just one of the 200 samples (0.5%) was positive for the S. typhi capsular gene (vi gene).
Conclusion: Due to the improvement in the health status of the country and the low typhoid carriers, it is recommended that efforts be focused on other hygienic issues.

Volume 2, Issue 4 (10-2016)
Abstract

Background: Salmonella typhimurium is one of the most important species of Salmonella that is intracellular parasite and attacks host mucus membrane. These bacteria can cause gastroenteritis, and their main transmission route is water, poultry, meat, egg, and raw food. The aim of this study was to detect three virulence genes associated with S. typhimurium named invA, STM4497, and fliC183 genes by Multiplex PCR method.
Materials and Methods: 183 samples of poultry were collected from food products in Zanjan (Iran) and cultured in BPW (Buffered Peptone Water) for 18 hr and at 37°C, and in RVS broth (Rappaport Vassiliadis Soya) for 6 hr at 41.5°C. After amplification of genomic DNA by Multiplex PCR method, occurrence of pathogen contamination was checked and compared with standard strain.
Results: From the total of 183 collected samples, 52(28.4%) samples were positive for S. typhimurium. The frequency of STM4497, fliC183, and invA genes were 49 (27%), 3 (2%), and 53 (29%), respectively.
Conclusion: Simultaneous detection of invA, STM4497, and fliC183 genes were recognized as a key for detection of S. typhimurium by Multiplex PCR method. 

Volume 3, Issue 9 (7-2006)
Abstract

Aerobic mesophilic counts (AMC), were obtained by swabbing 25 cm2 areas at seven site (neck, brisket, leg, flank, rib set, forehand, hind quarter) on beef carcasses, after each Slaughter process (skinning, evisceration, splitting, trimming and primary washing, final washing). Reduction in counts at individual sites were observed after trimming and primary washing (about 0.2 log cfu.cm-2 ) and final washing (about 0.2 log cfu.cm-2 ) similarly. Increases in counts at most outside sites were observed after skinning, (about 2.5 - 3.5 log cfu.cm-2) and after evisceration, at brisket (about 1 log cfu.cm-2) and forehand (about 0.5 log cfu.cm-2) respectively. The incidence of Salmonella and E. coli on beef carcasses were also obtained by swabbing the outside surfaces of 12 carcasses after each stage. A large number of increases in positive samples for E.coli and Salmonella was observed after skinning and after evisceration (16.6% and 9.2% respectively). After final washing Salmonella and E. coli were detected on 11.9% and 7.1% of samples. The impact of beef slaughter processes on carcass microbiology and their potential use as critical control points (CCPs) during beef production are discussed.

Volume 3, Issue 11 (12-2006)
Abstract

Food –borne diseases are important public health problems in the world. In recent years significant increase in the incidence of Salmonellas has been reported by WHO. Because Salmonellas resistance to antibiotics. The present study is to evaluate the prevalence of Salmonella in trails chicken meats in Tehran. Between Bahman 2004 to Aban 2005 we analyzed 198 samples of chicken meats in Tehran city. Each sample weighing approximately 800 g was collected. Salmonellas was isolated from 93 of the samples analyzed (47%). The predominant serotypes were S. Enteritis (48.4%), S. Hadar (26.9%) and B4 (22.3%). Other serotypes such as S. Derby and Paratyphoid B were in much lower levels.

Volume 4, Issue 1 (2-2018)
Abstract

Introduction: The use of antibiotics in food-producing animals has elevated concerns regarding their potential affect on human health. Resistant Salmonella may be transmitted through the food chain to humans. The aim of this study was to determine the prevalence of tetracycline resistance genes among tetracycline-resistant Salmonella enterica from Iran.
Material and methods: In this experimental study, A total of 4369 stool specimens were collected via rectal swab from hospitalized children under the age of 5 with watery diarrhea, with or without blood, mucus and stomach cramps. Antimicrobial susceptibility profiles of Salmonella isolates were performed and Minimum inhibitory concentration (MIC) of tetracycline was assessed. Bacteria were grown on blood agar at 37°C overnight, and genomic DNA was extracted. For evaluating of PCR products used of 1.5% agarose gel in TBE buffer at for 80min.
Findings: High level of resistance was observed against minocycline (78.5%), tetracycline (76.0%), nalidixic acid (66.6%) and streptomycin (42.0%). The MIC for 46.0% of the isolates was 256µg/ml, while 15.6% showed the MIC of 128µg/ml and the remaining revealed 64µg/ml MIC to tetracycline. Among the 33 tetracycline-resistant isolates the tet(A) or tet(B) genes were detected in 10 (23.8%) and 5 isolates (11.9%), respectively. The tet(A)and tet(B) genes were identified in 2 out of the 42 tetracycline-resistant Salmonella isolates (4.8%). The tet(C) or tet(D)genes were not found among tetracycline-resistant isolates.
Conclusion: Resistance to Salmonella strains is increasing. The predominant tetracycline-resistant gene is tet(A) followed by tet(B).

Volume 4, Issue 3 (12-2015)
Abstract

Protein hydrolysate (PH) from viscera of cultured Siberian sturgeon (Acipenser baerii) was produced. To optimize the production conditions, Response Surface Method (RSM) was employed to examine the effects of three different operating conditions, including time, pH, and enzymatic concentration (Alcalase) on the degree of hydrolysis.The mathematical model showed acceptable fitness of the experimental data as R2 equaled 0.97, which indicated  that   major part of  the  variability  within  the  range  of  values could  be explained  by  the  model. The results showed that the highest degree of hydrolysis (58.21%) was related to the treatment which happened at the enzymatic concentration of 2%, 60 minutes time, and pH=8. Treatment under hydrolysis condition (i.e., E/S = 2%, Time = 45 min, and pH = 8.5) had the highest protein content (42.37g/l), which was used as an alternative to commercial peptone medium (Triptic soy broth) to assess the growth of Salmonella typhi bacteria from 0 to 48 hours. Although there was an upward trend in growth rate of S. typhi both in control and No. 15 (Alcalase) treatments, the log growth of control treatment was found to be better than that of Alcalase treatment. However, there existed no significant difference between the two treatments.

Volume 5, Issue 3 (12-2016)
Abstract

Based on the gut content analysis of 278 specimens of brown trout, Salmo trutta, in the Lar Reservoir and its basin, including streams of Delichay, Ab Sefid, Elarm, Lar and Siah Plas, the summer food habits were found to be general and depended on the abundance of preys. Considering the “index of relative importance” in all stations, the most consumed prey items in the streams were Diptera larva, Ephemeroptera and Trichoptera nymphs, while Hymenoptera constituted the main prey in the reservoir. It was found that the gender had no significant effect on the feeding habits of the adult brown trout. 

Volume 5, Issue 3 (9-2019)
Abstract

Aims: Foodborne infections caused by bacteria, including Salmonella enteritidis, Shigella flexneri, and Escherichia coli O157:H7 are one of the most common diseases among poultry and humans. The purpose of this study was the simultaneous and rapid detection of important microorganisms found in fecal samples of poultry and poultry workers.
Materials & Methods: A total of 144 fecal samples were taken from poultry and poultry farms workers. Fecal swabs were cultured on specific media, and biochemical tests were performed for further confirmation of bacterial isolates. Moreover, genomic DNA of fecal swabs was extracted for molecular identification of S. enteritidis, E. coli O157: H7, and S. flexneri species using multiplex-PCR technique.
Findings: According to the multiplex-PCR technique results, 16.7, 13.9, and 9.5% of the poultry samples were positive for the presence of S. enteritidis, E. coli O157: H7, and S. flexneri species, respectively; whereas culture method results showed the corresponding prevalence rates of 18.1, 15.2, and 12.5% for the above species. Moreover, regarding the samples collected from the poultry farms workers, multiplex PCR showed the prevalence rates of 6.9, 12.5, and 4.2% for S. enteritidis, E. coli O157: H7 , and S. flexneri species, respectively; whereas culture method showed the corresponding prevalence rates of 8.3, 13.9, and 13.9% for the above species.
Conclusion: In the current study, the sensitivity and specificity of multiplex-PCR in detecting S. enteritidis, E. coli O157: H7, and S. flexneri species were 74 and 100% for samples taken from the poultry farms workers, and 82.2 and 100% for samples taken from the poultry, respectively, suggesting the possibility of using a designed multiplex-PCR method for rapid detection of infectious agents in poultry farms.

 

Volume 5, Issue 4 (12-2019)
Abstract

Objectives: The present study aimed to investigate the prevalence of Salmonella serotypes in slaughtered broilers in Kermanshah province and investigate the susceptibility of isolated Salmonella to antibiotics.
Methods: In this cross-sectional, 10 carcasses were randomly selected from each of 25 slaughtered broiler flocks that were obtained from their cloacae. This study was conducted in 2014 in Kermanshah province. Samples were transferred into the Selenite F enrichment broth and incubated at 43 °C for 12-18 h. Antibiotic susceptibility pattern of all isolates to be performed using the disk diffusion method. Also, the agglutination test on slide was performed on Salmonella isolates using the specific antisera to detect Salmonella serotypes.
Findings: In the present study, 250 (33%) samples of Salmonella were isolated from 750 cloacal samples of broilers. After serotyping, the most frequent serotype was as follow: Enteritidis serotype (55.2%), Infantis serotype (38%) and Typhimurium serotype (25.6%). The results of antibiotic susceptibility pattern indicated that 100% of strains were susceptible to gentamicin, enrofloxacin, imipenem and ceftriaxone; and the highest resistance was observed to nalidixic acid and nitrofurantoin. Furthermore, 202 (80%) out of 250 Salmonella isolates had multiple resistance to three or more antibiotics and accounted as MDR isolates.
Conclusion: According to the results of the present study, it is essential to detect pollution sources and pathogenic serotypes, the possibility of transferring Salmonella through poultry to humans and increasing the frequency of resistant isolates to antibiotics. It is strongly recommended to avoid the overuse of antibiotics without performing antibiotic susceptibility patterns.

 


Volume 6, Issue 4 (11-2020)
Abstract

Background: Foodborne diseases caused by Salmonella are considered as a global health concern, especially in low-income countries. Rapid and specific detection of this infective agent is highly important in the outbreak control. The current study aimed to design and optimize a LAMP method and to compare its sensitivity and efficiency with the PCR method in the detection of S. typhi in food.
Materials & Methods: Food samples including mayonnaise and vegetable salad were inoculated with S. enterica serovar Typhi. Sensitivity and detection limit of LAMP test were investigated at different concentrations of contaminated mayonnaise and vegetable salad. invA gene was chosen as the target gene for bacterial detection by PCR and LAMP tests.
Findings: The detection limit of Samonella was estimated to be 16 CFU/mL using LAMP and PCR. LAMP reaction revealed a visible turbidity, indicating the accurate amplification of the selected target gene and proper identification of Salmonella at different dilutions of the studied food samples.
Conclusion: The present study indicated that LAMP is a rapid, cost-effective, and specific technique for the identification of Salmonella. This method could be used in laboratories with minimal equipment without the need for costly molecular detection methods.

Volume 7, Issue 2 (9-2016)
Abstract

Salmonella is the serious and prevalent bacteria that has important role in epidemic infections. Beside increase of antibiotics resistance in bacteria make that abundance researches did for introduction of replacement method for beard with bacteria infections. Copper NANO oxide particles are components that their anti-microbial nature be evidenced. In this research for discover of NANO particles probably mechanism on the genome of bacteria, salmonella selected as a model for Gram-negative bacteria. In this regard, at first the bacteria were treated with 30 and 60 µg/ml copper oxide NANO particles. At time intervals of 2, 4, and 24 hours. In this doses, bacteria was growth .So bacteria were treated with 90 and 120 µg/ml copper oxide NANO particles. In these doses growth of bacteria even after 24 h completely were stopped .Then their DNA were extracted. In order to investigate the effects of copper oxide NANO particles on the genome, the chain reaction techniques of (RAPD-PCR) was employed .Using the software NTSYS-PC, the results obtained from electrophoresis of PCR products on agarose gel were analysis. The results of the study revealed that copper oxide NANO particles not only affects the growth of bacteria but also affect the sequencing of genomic DNA and leads to the changes of them in different points.

Volume 8, Issue 4 (10-2019)
Abstract

This study was aimed to evaluate the effect of Levels of Choline on the growth performance (WG, SGR, FCR, CF, PER and HIS), Carcass Compositions, and Haematological of Caspian salmon. 270 (8.82±0.38 g) were randomly distributed in 18 fiber glass tank with treeplicatefor 10 weeks. Experimental diets were also prepared by adding 0, 250, 500, 750, 1000 and 2000 mg/kg the basal diet (Control, Cho250، Cho500, Cho1000 and Cho2000) to evaluategrowth performance, carcass composition, and some haematological parameters. The final weight, weight gain, specific growth rate index, proteinefficiency ratio, obesity coefficient, and feed conversion ratio of fish fed with diet containing appropriate levels of choline (750-1000 mg/kg-1) were significantlyhigher than fish fed with other diets. With increasing choline in fish diet, body fatand protein concentrations significantly increased, but carcass moisture decreased. Also, addition of 750-1000 mg/kg-1choline to diet caused a significant diference in the activity of liver enzymes (ALT, AST, ALP and LDH), compared with control treatment and 2000 mg/kg-1.The results showed a significant increase in growth parameters and optimal carcasscomposition of Caspian salmon, the most suitable amount of choline is 750-1000 mg/kg-1in the fish diet (p<0.05).
The results of this study indicated, that dietaryup to 1000 mg/kg-1 to be negetivecooparation on growth performance, liver enzymesin Caspian salmon, salmo trutta caspius has moderate Choline requirement 750-1000 mg/kg-1 as fed

Volume 9, Issue 1 (3-2023)
Abstract

Backgrounds: The burden of bacteremia in febrile cases is still poorly understood in Nigeria as in many sub-Saharan African countries due to diagnostic limitations. This study aimed to determine the prevalence of Salmonella bloodstream infections and antimicrobial resistance patterns of bacterial isolates recovered from febrile patients in Lagos, Nigeria.
Materials & Methods: A total of 300 blood samples were collected from febrile patients attending four medical centers in Lagos during August 2020 to July 2021. Clinical isolates were identified using API 20E kit. qPCR was used to detect Salmonella isolates in positive blood culture samples using a specific primer set. All isolates were subjected to antimicrobial susceptibility tests using standard procedures.  
Findings:  Totally, 55 bacterial isolates belonging to six bacterial genera were identified, including Salmonella (n=4, 7.27%), Klebsiella species (n=23, 41.82%), Escherichia coli (n=6, 10.91%), Proteus species (n=13, 23.64%), Serratia species (n=7, 12.73%), and Citrobacter species (n=2, 3.64%). In this study, the detection rate of Salmonella isolates in positive blood culture samples using qPCR and invA gene primer set was 100%. Salmonella isolates were 100% resistant to ceftazidime, cefotaxime, and doripenem. Multidrug resistance (MDR) was observed in Salmonella and other bacterial isolates.
Conclusion:  In this study, qPCR using the invA primer set was found to be highly specific for Salmonella detection. All the bloodstream bacterial pathogens in this study were MDR; thus, there is a need for continuous evaluation of antibiotics in medical settings.  Further molecular studies on these bacterial isolates is essential.


Volume 10, Issue 0 (2-2008)
Abstract

Objectives: Salmonella typhimurium is important food-borne pathogen responsible for gastroenteritis. In this work a polymerase chain reaction based enzyme linked immunosorbent assay (PCR-ELISA) was developed to identify Salmonella typhimurium. Materials and Methods: The rfb gene which is responsible for biosynthesis of the Salmonella O-antigenic lipopolysaccharide was selected as the target sequence. The selected primers amplified fragment size of 882bp of S. typhimurium. Food samples contaminated with Salmonella typhimurium as well as clinical and standard samples were used in this investigation. The PCR products randomly labeled with Dig-11-dUTP were transformed to a plate coated with streptoavidin and tested with anti digoxigenin. An internal biotin-labeled probe was used to confirm the amplified PCR product. Results: The specificity of the assay toward S.typhimurium samples was confirmed by testing 20 Salmonella and 6 non Salmonella strains. ELISA increased the sensitivity of the conventional PCR method by approximately 1000 fold. Conclusion: The method presented here is a rapid and specific alternative for the traditional time consuming culture methods for the detection of S. typhimurium in food and clinical samples. Due to its high specificity and sensitivity, our method finds its place as an alternative to PCR in large scale screenings, for detection of S. typhimurium.

Volume 10, Issue 41 (10-2013)
Abstract

Antimicrobial effect of caseinat edible film containing the essential oil of Zataria multiflora Bioss was investigated against tow gram-negative bacteria named Salmonella typhymurium (ATCC14028), Escherichia coli O157:H7 (ATCC35218) and agram-positive bacteria Staphylococcous aureus (PTCC1431). The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the tested essential oil were determinate by using a broth dilution susceptibility test at 6 different concentrations (125, 250, 500, 1000, 2000 and 4000 ppm). The essential oil from Avishan Shirazi( Zataria multiflora Bioss) was most effective against S. aureus, the MIC and MBC values  in the presence of E. coli O157:H7 and S. typhymurium were 500 for both of them. The antimicrobial effect of caseinate film was studing using disk diffusion method. Our result showed that the larger inhibitory diameter was belonged to S. aureus (mean=25.17mm) mean diameters of inhibitory effect for S. typhymurium and E. coli O157:H7 were 15.20 and 17.62 mm respectively.  

Volume 11, Issue 4 (11-2020)
Abstract

Spermatogonial stem cells (SSCs) are unique with an important role in the transmission of genetic information to the next generation. Thus, they play an important role for the production of interspecies germ line chimeras. Therefore, the objective of this study was to produce chimera through the intraperitoneal transplantation of Caspian brown trout SSCs into newly-hatched rainbow trout. Spermatogonial cell were isolated from the testes of 8-month-old Caspian brown trout through enzymatic digestion. The spermatogonial cell suspension was enriched using differential plating technique to remove testicular somatic cells. After culturing for 48 h in L15 supplemented with 10% serum, suspended cells were collected and stained with the fluorescent membrane dye PKH26. The stained cells were intraperitoneally transplanted into triploid rainbow trout hatchlings. At 15 and 30 days after transplantation, the recipients were investigated under a fluorescent microscope. The gonads of recipients were dissected for molecular analysis at 180 days after transplantation. Transplanted spermatogonial cells migrated toward and incorporated into recipient genital ridges. The presence of the Caspian brown trout genetic material was confirmed by PCR in 41.4% of the rainbow trout testes. These results demonstrated for the first time that the interspecies spermatogonial transplantation was successful in rainbow trout and that the somatic microenvironment of the rainbow trout gonad can support the colonization and survival of intraperitoneally transplanted cells derived from a fish species belonging to a different genus. Therefore, the SSCs transplantation can be used as a tool for conservation of Caspian brown trout genetic resources.
Seyyed Mohammad Ali Hojati, Alireza Dastafshan,
Volume 12, Issue 1 (1-2005)
Abstract

Fictional names have been one of the most important and serious topics in the contemporary philosophy of language and metaphysics.Several questions such as “Do fictional names refer to any objects?” “Are fictional characters existent objects?” have resulted in a considerable literature of philosophy. In this essay, we will follow two objectives. First we will describe and elaborate the ideas of three great philosophers who believe that fictional names are genuine and proper names which do refer to existent fictional characters. Second we will criticize the theories of two philosophers (Peter Van Inwagen and Saul Kripke’s theories) and will eventually defend the third i.e. Nathan Salmon’s theory of fictional names. Through the issues we will presuppose direct reference theory as our main semantic theory for proper names .

Volume 16, Issue 91 (9-2019)
Abstract


 
Abstract
Extracts, herbal essential oil and natural ingredients have known antibacterial properties and can be used as food preservatives.  Quinoa seed is a rich source of protein with strong antioxidant and antibacterial properties than other cereals. The aim of this study was to investigate the antimicrobial activity of peptide extracted from quinoa on Staphylococcus aureus and Salmonella enterica bacteria.  To determine the optimal condition of the peptide hydrolysis with the best antimicrobial property was used pepsin and alcalase enzyme at different temperatures and times. Antibacterial effects of hydrolyzed peptide from quinoa proteins on two types of gram positive and negative bacteria (Staphylococcus aureus and Samunella antrica) were compared with the gentamicin antibiotic by Agar well diffusion method. The highest growth inhibition zone in Staphylococcus aureus and Salmonella enterica   were seen at enzyme activity 60 (Anson per kg protein), Temperature of 50, 150 minutes and 800 μg / ml concentration (13.13 ± 1.00 for Staphylococcus aureus and 11.00 ± 1.1 for Salmonella enterica). According to the findings, the peptide derived from protein quinoa has a good inhibitory effect on Staphylococcus aureus and Salmonella enterica bacteria. It is recommended that further research is done on the quinoa seed and its peptides be used as a natural preservative in foods.
KEYWORDS: quinoa seed, active peptide, Staphylococcus aureus, Salmonella enterica
 
 

Volume 16, Issue 93 (11-2019)
Abstract

Masske butter or butter derived from yogurt is a traditional butter used in southern Khorasan with a wide range of lactic bacteria. The aim of this study was to investigate the antibacterial effect of lactate isolates against of Staphylococcus aureus and Salmonella enterica. In this research, lactic isolates were first detected by PCR method, and then microdilution method was used to evaluate the antimicrobial activity of the isolates. BLAST of sequences of S16 rDNA gene with sequences stored in the NCBI database led to the identification of the genus Lactobacillus bulgaricus, Enterococcus faecium, Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus delbrueckii and Enterococcus hirae. The results of antimicrobial activity evaluation against Staphylococcus aureus and Salmonella enterica bacteria showed that all isolates were able to inhibit the growth of these two pathogens, and their inhibitory percent from 55/46 to 84/49 and from 55/46 to 56/55 respectively was variables. Also, the results showed that Lactobacillus plantarum B38, Enterococcus hierae B224, Lactobacillus delbrueckii B37 had the highest inhibitory effect against Staphylococcus aureus (P>0.05) and Lactobacillus plantarum B38 showed the highest percentage of inhibition against Salmonella enterica (P<0.05). In addition, it was found that the inhibitory effect of all isolates against Staphylococcus aureus was significantly higher than Salmonella enterica (P< 0.05). Therefore, lactic acid bacteria isolated from the Masske butter can be used to control the food borne pathogens and food spoilage microorganisms.
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