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The main purpose of this study was survey on achieving recombinant DNA vaccine (live delivery) against streptococcusis for Rainbow trout (Onchorhynchus mykiss) Immunization. Initially, a total of 515 samples were collected from the head kidney of diseased fish (weigh 50_ 200g) in 72 farms of 8 provinces. Approximately, 40% (206 samples) of specimens were infected to Streptococcus species. Then were isolated 172 DNA samples and consequently, five pathogenic species have been identified, including S. iniae, S. faecium, S. agalactiae, S. dysgalatiae, and S. uberis. The enzyme phosphoglucomutase (PGM) has recently been discovered to play an important role in polysaccharide capsule production and virulence in S. iniae. Therefore, was initially isolated S. iniae and cloning phosphoglucomutase gene. Then, the PGM gene was amplified successfully and cloned in pTZ57R cloning vector. The recombinant plasmid was sub cloned into pETD uet-l expression vector by restriction enzymes and confirmed by PCR. Meanwhile, for amplifying simA and cpsD genes were used universal primers pNZ8148 and special for simA and cpsD genes.The recombinant bacteria Lactococcus lactis (NZ9000) was used for transformation the plasmid into Lactococcus lactis. Vaccination was performed by oral, bath and injection (peritoneal) methods. The efficiency of g2 was better than g1in these three methods and all of groups. The determination of IgM level, or detection of anti S. iniae antibody was carried out by using ELISA. The results revealed that there was a significant (p

The main purpose of this study was survey on achieving recombinant DNA vaccine (live delivery) against streptococcusis for Rainbow trout (Onchorhynchus mykiss) Immunization. Initially, a total of 515 samples were collected from the head kidney of diseased fish (weigh 50_ 200g) in 72 farms of 8 provinces. Approximately, 40% (206 samples) of specimens were infected to Streptococcus species. Then were isolated 172 DNA samples and consequently, five pathogenic species have been identified, including S. iniae, S. faecium, S. agalactiae, S. dysgalatiae, and S. uberis. The enzyme phosphoglucomutase (PGM) has recently been discovered to play an important role in polysaccharide capsule production and virulence in S. iniae. Therefore, was initially isolated S. iniae and cloning phosphoglucomutase gene. Then, the PGM gene was amplified successfully and cloned in pTZ57R cloning vector. The recombinant plasmid was sub cloned into pETD uet-l expression vector by restriction enzymes and confirmed by PCR. Meanwhile, for amplifying simA and cpsD genes were used universal primers pNZ8148 and special for simA and cpsD genes.The recombinant bacteria Lactococcus lactis (NZ9000) was used for transformation the plasmid into Lactococcus lactis. Vaccination was performed by oral, bath and injection (peritoneal) methods. The efficiency of g2 was better than g1in these three methods and all of groups. The determination of IgM level, or detection of anti S. iniae antibody was carried out by using ELISA. The results revealed that there was a significant (p

Nowadays, medical plants extract is used in aquaculture industry to enhance growth, immune system and fish resistance to different pathogens. In this study, some non-specific immune responses, hematology and biochemical parameters in rainbow trout juveniles (16 gr mean weight) and their resistance to Streptococcus iniae were evaluated following oral administration of Echinacea purpurea and Astragalus sp. extract. Three concentrations (0.5, 1 and 1.5 gr/kg of feed) of Echinacea purpurea and three concentrations (2, 3 and 5 gr/kg of feed) of Astragalus sp extract and control group were used for 60 days. Parameters evaluated included: levels of C4, C3 (complement components), free oxygen radicals (respiratory burst), Lysozyme, numbers of lymphocytes, monocytes and neutrophils. In the end, the relative survival rate (RSR) of fish was evaluated against S. iniae. The results showed that the levels of C3, lysozyme, oxygen free radicals, the number of neutrophils and lymphocytes in the experiment groups (the highest dose) compared to control group were increased significantly (p 0.05). The relative survival rates of fish following challenge with Streptococcus iniae, were 91/11, 93/33 and 44/44 percent in experiments (Echinacea purpurea and Astragalus sp.) and control groups, respectively. In conclusion, it may be state that Echinacea purpurea and Astragalus sp. extracts enhance the non-specific immune system and fish resistance against Streptococcusis, and it seems it can be used as immunostimulant in feed. Iranian Fisheries Science Research Institute Published

Nowadays, medical plants extract is used in aquaculture industry to enhance growth, immune system and fish resistance to different pathogens. In this study, some non-specific immune responses, hematology and biochemical parameters in rainbow trout juveniles (16 gr mean weight) and their resistance to Streptococcus iniae were evaluated following oral administration of Echinacea purpurea and Astragalus sp. extract. Three concentrations (0.5, 1 and 1.5 gr/kg of feed) of Echinacea purpurea and three concentrations (2, 3 and 5 gr/kg of feed) of Astragalus sp extract and control group were used for 60 days. Parameters evaluated included: levels of C4, C3 (complement components), free oxygen radicals (respiratory burst), Lysozyme, numbers of lymphocytes, monocytes and neutrophils. In the end, the relative survival rate (RSR) of fish was evaluated against S. iniae. The results showed that the levels of C3, lysozyme, oxygen free radicals, the number of neutrophils and lymphocytes in the experiment groups (the highest dose) compared to control group were increased significantly (p 0.05). The relative survival rates of fish following challenge with Streptococcus iniae, were 91/11, 93/33 and 44/44 percent in experiments (Echinacea purpurea and Astragalus sp.) and control groups, respectively. In conclusion, it may be state that Echinacea purpurea and Astragalus sp. extracts enhance the non-specific immune system and fish resistance against Streptococcusis, and it seems it can be used as immunostimulant in feed.

In this study, some non-specific immune responses and hematological parameters in rainbow trout juveniles (16g mean weight) and their resistance to Streptococcusis were investigated following dietary administration of 3 concentrations (0.5, 1, 1.5g/kg of feed) of Echinacea purpurea extract. The non-specific immune response and hematological parameter compared with control group for 60 days. Evaluated parameters included were of C3, C4, (complement components), superoxide ions (respiratory burst), lysozyme activity, number of WBC, percentage of blood lymphocytes, monocytes and neutrophils. At the end of trial, the relative survival rate (RSR) of fish was evaluated against S. iniae. The results showed that the levels of C3, lysozyme activity, superoxide ions, number of WBC and percentage of neutrophils in the experiment groups (the highest concentration, 1.5g/kg of feed) were increased significantly compared to the control group. Whereas, no significant difference was found in the value of C4 and the percentage of monocytes and lymphocytes in comparison to the control group. The relative survival rates of fish following challenge with Streptococcus iniae, were 91.11 and 44.44 percent in experiment (Echinacea purpurea, concentration of 1.5g/kg of feed) and control group, respectively. In conclusion, the results of the present study demonstrated that Echinacea purpurea extract enhanced the non-specific immune system and fish resistance against streptococcusis, suggesting that this extract might be used as immunostimulant in fish feed.

Streptococcosis is an acute infectious disease that causes mortality in marine and freshwater aquacultures. One of the most important hosts is susceptible to the disease of rainbow trout and during the past decade its industrial production has been growing in Iran. According to FAO, Iran is among the 10 countries producing fish in the world. The most important bacteria causing Strptococcosis includes Strptococcus, Vagococcus and Enterococcus genera. But in all cases, the clinical sings are the same. More than a decade has passed since the first report of this disease in Iran and unfortunately, this disease has become the most important problems of trout production in Iran. Therefor, 72 farms were selected in 8 provinces including Mazandaran, Gilan, Lorestan, CharmahalBakhtiyari, Fars, Kermanshah, Tehran and Kokiloye-Boyer Ahmad and a total 520 moribund and apparently healthy rainbow trout (weight 50 – 200gr) were collected during summer 2008 to 2009. Fish kidney, spleen and liver samples were culture aseptically and finally 206 isolates were identified as gram positive cocci. Using conventional biochemical test, S.uberis, S.agalactiae, S.dysgalactiae, S.faecium and S.inia. Additionally, 172 from 206 isolates were confirmed as S.uberis ، S.agalactiae ، S.dysgalactiae ، S.faecium and S.inia using a PCR assay. Based on the results, the most prevalent is belong to S.uberis (isolated from 5 of 7 province), S.dysgalactiae (isolated from 4 of 7 province), S.agalactiae (isolated from 2 of 7 province) and S.faecium and S.inia (from 1 of 7 province) respectively. It is necessary to mention, S.inia was identified just to Fars and any gram positive cocci was isolated from Tehran. Iranian Fisheries Science Research Institute Published

In this study, influence of modified atmosphere packaging on shelf life of trout (Oncorhynchus mykiss) (whole fish without visceral and without head and tail fish) stored in 4 to 6ºc was examined. Fish stored in MAP condition and control samples, in different time, were tested for spoilage chemical factors (TVN, PV and pH), microbial parameters (total viable count, clostridium botulinum) and sensory factors too. Mixed gases including co2 (30-50%), N2 (40-65%) and o2 (0 to 20%) were used for trout (without head and tail =6 treatments) and (whole fish without visceral and control = 2 treatments) statistical the analysis results showed that examined factors were significant difference during storage (P

In this study, influence of modified atmosphere packaging on shelf life of trout (Oncorhynchus mykiss) (whole fish without visceral and without head and tail fish) stored in 4 to 6ºc was examined. Fish stored in MAP condition and control samples, in different time, were tested for spoilage chemical factors (TVN, PV and pH), microbial parameters (total viable count, clostridium botulinum) and sensory factors too. Mixed gases including co2 (30-50%), N2 (40-65%) and o2 (0 to 20%) were used for trout (without head and tail =6 treatments) and (whole fish without visceral and control = 2 treatments) statistical the analysis results showed that examined factors were significant difference during storage (P

Over the past few years, the syndrome of streptococcosis has been associated with outbreaks in rainbow trout (Oncorhynchus mykiss, Walbaum) and caused significant economic losses in the aquaculture industry in Iran. The main purpose of this work was molecular identification of some causative agents of streptococcosis in rainbow trout. A total of 520 samples were collected from the head kidney of diseased fish (weight, 50_200g) in 72 farms of 8 provinces in Iran, during 2008 to 2009. Bacterial isolates representing morphology and biochemical profiles of Streptococcus spp. were further confirmed by polymerase chain reaction (PCR). DNA extraction was carried out from a single colony by using the extraction promega kit following the conditions described by the supplier. The PCR assay was developed based on the 16S rRNA and glucose kinase genes of Streptococcus spp. for the rapid and specific detection and identification of this pathogen from different sources. Approximately 40% of specimens were infected to Streptococcus spp. Consequently, five pathogenic species have been identified, including S. iniae in Fars province, S. faecium in Mazandaran province, S. agalactiae in Gilan and Mazandaran provinces, S. dysgalatiae in Lorestan, Kohgiluyeh and Boyerahmad, Gilan and Kermanshah provinces and S. uberis, which was common in all provinces (except Mazandaran and Lorestan). The dominant species (based on important species index) were S. uberis, S. dysgalactiae and S. agalactiae, respectively.