[Genetic diversity of isolated Lactococcus garvieae from rainbow trout [Onchorhynchus mykiss] mortality in Iran]

Lactococcus garvieae is one of the main causative agents of Streptococcosis/Lactococcosis in farmed fish particularly in rainbow trout causing remarkable losses each year. To study the genetic diversity of Lactococcus garvieae strains recovered from the mortality of farmed rainbow trout in different provinces of Iran. The Gram positive cocci were first obtained from the kidney tissues of diseased trout. The bacterial isolates were grown on blood agar and were then identified by PCR method. Their genetic diversities were then studied using RAPD. The recovered gram positive cocci strains were identified as L. garvieae producing a 1100 bp in PCR procedure. In RAPD studies using 6 random primers [P1-P6], only primer P4 was able to produce higher number of bands [five bands]. Therefore, using this primer four profile patterns consisting of 560-1330 bp in 5 bands, 56-1260 bp in 5 bands, 560-1260 bp in 4 bands and 560-1200 bp in 5 bands were obtained. The phylogenetic tree of the RAPD product using UPMGA software included these strains in three different clusters with four different genetic groups. The results of this study clearly show that L. garvieae strains from the diseased rainbow trout in the north part of Iran are geneticly different from those in the west country, although there is some genetic similarity between some strains of these two regions of country

study of the plerocercoid of diphyllobothriidae [cestoda, pseudophyllidea] in two cyprinid hosts, Abramis brama and Alburnoides bipunctatus from north and northwest of Iran

The plerocercoid stage of Pseudophyllidean cestoda infected a wide range of fresh water fish, particularly the members of the Cyprinidae family. The parasite species are the most common pathogens that have severe effects on fish. The aim of the present study is to determine the occurrence and distribution of the plerocercoid of Diphyllobothriidae in two freshwater fish from north and northwest of Iran. Finally, we discuss the role and dynamics of these species of fish in the transmission of infection. This study was carried out from September 2011 to September 2012on a total of 883 A. bipunctatus and 418 A. brama from north and northwest of Iran. The samples were analyzed to find the plerocercoid infection. From a total number of 883 A. Bipunctatus and 418 A. brama fish samples, 558 fish [63.19%] of the former and 67 fish [16.02%] of the latter were infected. The rate of infection was significantly lower in winter [p<0.01]. Also, the weight of infected fish was significantly lower than noninfected ones [p<0.01]. Moreover, the infection in northwest of Iran was significantly higher than north of Iran [p<0.01]. The family of Diphyllobothriidae is an important cestode and the prevention programs to break the cycle of infection are essential. More suitable solutions to tackle the problem, further epidemiological studies on other fresh water sources of Iran are needed

Identification of Gyrodactylus gurleyi in Carassius auratus using morphometric and molecular characterization

Gyrodactylus is a small monogenean ectoparasite that lives on the skin and fins of most of the world's fish species. Gyrodactylus appears to be one of the most prevalent parasites found in ornamental fish, especially in Cyprinids. Goldfish [Carassius auratus] are a popular ornamental fish that are highly contaminated by Gyrodcatylus. The present study is aimed to identify morphological and molecular characteristics of the Gyrodactylus parasite on gold fish. The morphological identification of Gyrodactylus specimens was performed using the measurements and drawings of opisthaptoral hard parts of the parasites. The molecular species description was based on a polymerase chain reaction [PCR] of partial sequence of the 5.8S region of ribosomal RNA, and a partial sequence of the internal transcribed spacer 2 [ITS2] of ribosomal RNA. The nucleotide sequences of the PCR products were compared with corresponding sequencing registered in GenBank. Based on the morphometric analysis and sequencing, the Gyrodactylus specimens were described as Gyrodactylus gurleyi. A combination of molecular techniques with morphological analysis seems to be the best approach for the identification of Gyrodactylus speices

[Study of gregarine infection in Kiddi shrimp Parapenaeopsis stylifera] and pacific white shrimp [Litopenaeus vannamei] in Khouzestan province]

One of the most important causes of shrimp diseases in wild environment and Farms are Parasitic disease and Gregarines are the reutine parasites in shrimp. This study was conducted in Khouzestan Province, to determine the prevalence and intensity of Gregarine parasites in Kiddi shrimp [Prapenaeopsis stylifera], a natural species of Persian Gulf, and Pacific white shrimp [Litopenaeus vannamei], currently the major cultured species in Iran. Shrimps were randomly collected from Persian Gulf and Choebde shrimp farms in Abadan, Digestive tracts of the shrimps were studied using wet-mount diagnostic procedure. In this study no Gregarine parasites were observed in Pacific white shrimp whereas infection rate among Kiddi shrimp was 32.5% including Genera: Nematopsis, Rotundula, Heliospora and other unknown Gregarine parasites. The highest infection rate belonged to Genus Nematopsis[%9.55] According to the published materials available, this is the first report of Kiddi shrimp being' parasitized with [Gregarine parasites. Also the relationship between shrimp body length and the rate of infection was found to be positive. But there was no meaningful relationship between sex and the rate of infection

[Study on hematology and serum biochemistry of common carp [Cyprinus carpio] after low cadmium concentration exposure]

High concentration of heavy metals or long time exposure to low concentrations of these metals can usually decrease the hematological indices in fish. Therefore the aim of this study was to indicate changes in hematology and serum chemistry of common carp [cyprinus carpio] after low cadmium concentration exposure. 60 apparently healthy common carp [mean weight of 700g] divided in two groups and transfred to 1000 liter indoor fiberglass tanks under controlled conditions. Treatment group was exposed to low concentration of cadmium [30ppb]. Blood were exsanguinated randomly from 5 fish in each group through the caudal vein at days 15 and 30 of exposure. The hematological and biochemical parameters [WBC, RBC, different count, hematocrit, total protein, albumin and globulin concentrations, albumin: globulin ratio, LDH, ALT, and AST] were determined. Results revealed that WBC counts decreased significantly on the 15th day of exposure [p<0.05]. Furthermore, WBC counts decreased significantly on the 30th day of exposure [p<0.05]. The levels of LDH after day 30 of exposure, significantly increased in the test group compared to the control. In the test group, LDH levels significantly increased at the 30th day of exposure. No significant differences have been observed between control and test groups in respect to the other parameters. This study showed that the exposure time for sublethal concentration of cadmium is an important factor for increasing the LDH levels in common carp

[Effects of eucalyptus globules labill essential oil on some immunological variables of common carp [cyprinus carpio]]

Influence of both dietary and bath administration of Eucalyptus globules labill was evaluated on some immunological variables of common carp [Cyprinus carpio] under temperature less than optimum in order to determine stimulatory effect of the essential oils. Fish weighing 30-35 g were bathed or fed with different doses of 30, 60 and 120 micro/L or mg/kg feed for a period of 8 days. Serum lysozyme activity, bactericidal activity, total white blood cells, total protein, globulin and albumin were measured on days 1, 2, 8, 15 and 23 after the essential oils administration. On day 23 post administration the remaining fish from each group were intraperitonealy injected with killed Aeromonas hydrophila [6x10[8] cells/ml] and antibody titer was measured 3 weeks later. The obtained results showed that Eucalyptus globules had a limited immunostimulatory effect on these immunological variables although antibody titers and total white blood cells in some test groups were significantly [p<0.05] higher than the control one. The reduction of the immunological factors is probably related to the lower water temperature, inappropriate administrating dose and duration of essential oils administration

Study on distribution of infectious hematopoietic necrosis [IHN] in five major provinces producing rainbowtrout [oncorhynchus mykiss] fry in Iran by indirect fluorescence antibody [IFAT] and nested -RT- PCR techniques

Distribution of infectious hematopoietic necrosis[IHN] was studied in five major provinces producing rainbow trout[Oncorhynchus mykiss]fry in Iran by indirect fluorescence antibody IFAT and nested-RT-PCR techniques. Also the effect of time duration was examined on some positive samples after 8 months post sampling. Samples of kidney, liver and spleen of rainbow trout fries collected from 27 trout farms were processed and examinated. Fourteen trout hatcher is located in all provinces were identified to be contaminated with IHNV tested by both techniques. The obtained results also showed that nested-RT-PCR is more sensitive than IFAT test particularly if samples are stored for a longer time

Isolation and identification of parasite and saprophyte fungi from fungal affected eggs of the rainbow trout [oncorhynchus mykiss] in Mazandaran province

The aim of the present study was to isolate and identify parasites and saprophytes from fungal affected eggs of Rainboe trout.The samples[n = 900] were obtained from six fish farm and transferred to mycology laboratory in stril tubes. The samples were inoculated in cculture media, [SDA, CMA, GPagar and hemp seeds cultures] at room temperature [18-24 C]. Twelve species of fungi isolated from the fungal eggs. Three isolated fungi were belonged to the saprolegniaceas' family including: Saprolegnia parasitica, Saprolegnia sp., Achlya sp. Other nine fungi were: Penicillium, Aspergillus, Paeciliomyces, Acremonium, Fusarium oxysporum, F.solani, Alternaria, Mucor and Helminthosporium. In this study three species of pathogenic aquatic fungi were Saprolegnia parasitica, Saprolegnia sp., Achlya sp. It seems that saprolegnia parasitica was the most important fungal egg infestation in Mazandaran salmonid hatcheries. Meanwhile, saprophytic fungi can help for spreading of fungal egg infection

Isolation and Identification of Phathogenic andSaprophytic fungi from gill lesions in cultivated lyprinids [common carp, silver carp and grass carp]

Isolation and identification of fungi from gill esions. Gill speciemens from the common carp Cyprinus carpio, silver carp [Hypophthalmichthys molitrix], grass carp [Ctenopharingodon idella]. The samples were obtained from the five fish arms in Mazandaran province and transferred to mycology laboratory with ice conditon. The samples were inoculated in culture media [Sabouroed glucose agar, glucose pepton agar and corm meal agar-choloramphenicol. Chi-square and t-test. Thirty-nine species of fungi were isolated from the gill lesions. The most important pathogenic fungi were Branchiomyces, Saprolegnia, Fusarium, Phoma and Exophiala. The most frequency isolated fungi were Fusarium [46.4ko[3]/41] and saprolegnia [25ko[3]/41], whereas Exophiala [3.6ko[3]/41] was showen the lowest frequency. This is the first report of isolation oi Branchiomyces, Phoma and Exophila from fish in Iran. It is concluded that the above-mentioned isolated pathogenic fungi may play an important rule in fish diseases. Thus this study should be continued into the future