Hemato-Immunological Responses and Disease Resistance in Siberian Sturgeon Acipenser baerii Fed on a Supplemented Diet of Lactobacillus plantarum.

A feeding trial was conducted to investigate the effects of different levels of dietary Lactobacillus plantarum on hemato-immunological parameters and resistance against Streptococcus iniae infection in juvenile Siberian sturgeon Acipenser baerii. Fish (14.6 ± 2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations [1 × 107, 1 × 108 and 1 × 109 colony-forming units (cfu) g-1] and a control (non-supplemented basal) diet for 8 weeks. Innate immune responses (immunoglobulin (Ig), alternative complement activity (ACH50) and lysozyme activity) were significantly higher in fish fed the 1 × 108 and 1 × 109 cfu g-1 L. plantarum diet compared to the other groups (P < 0.05). Furthermore, fish fed on various levels of L. plantarum significantly showed higher red blood cell (RBC), hemoglobin (Hb), white blood cell (WBC) and monocyte compared to those of the control group (P < 0.05). At the end of the feeding experiment, some fish were challenged with S. iniae to quantify the level of disease resistance. The mortality after S. iniae challenge was decreased in fish fed a probiotic. These results indicated that dietary supplementation of L. plantarum improved immune response and disease resistance of Siberian sturgeon juvenile.

Synbiotic (Biomin imbo) alters gut bacterial microflora of Russian sturgeon, Acipenser guldenstadti (Brandt & Ratzeburg, 1833) in a time-dependent pattern.

We investigated the efficiency of Synbiotic (Biomin imbo) in alternation and stabilization of gut microflora of Russian sturgeon, Acipenser guldenstadti. For this purpose, five experimental treatments and one control group with three replicates were considered. In treatment groups, fish were fed with diet containing 1 (T1), 1.5 (T2), 2 (T3), 2.5 (T4) and 3 (T5) g Synbiotic/kg diet. In control group, fish were fed without supplement of Synbiotic. Sampling for bacterial studies was conducted at days 20, 40 and 60 after the beginning of the experiment. According to results, there were no significant differences in total bacterial count between Synbiotic treatments and also in comparison with control group 20 days after the beginning of the experiment (P > 0.05). At days 40 and 60 of experiment, the highest total bacterial counts were observed in control and T1 group respectively. At day 20, the lactic acid bacteria count was higher significantly in Synbiotic treatments compared to control group (P < 0.05). In all sampling times (i.e. days 20, 40 and 60), the highest lactic acid bacteria count was observed in fish fed with 3 g Synbiotic/kg diet i.e. treatment 5 (P < 0.05). In each experimental group, total bacteria and lactic acid bacteria counts increased significantly as the duration of experiment expanded. In this regard, these parameters were significantly higher at day 60 compared to day 40 and 20 (P < 0.05). In conclusion, our results showed that Synbiotic (Biomin imbo) alters and stabilizes efficiently the microflora of Russian sturgeon gut towards lactic acid bacteria in a time-dependent pattern.

Hematological characteristics associated with parasitism in Pikeperch Sander lucioperca (Percidae) from Anzali Wetland.

A total of 120 Sander lucioperca (Percidae) were captured and investigated for parasites and also haematological parameters were analysed and compared between infected and uninfected fish. The haematological analysis showed reductions in haematocrit, haemoglobin, red blood cell, whereas with blood cell (WBC) and lymphocyte significantly increased (P < 0.05) in infected fish, whereas with blood cell (WBC) and lymphocyte significantly increased (P < 0.05) in infected fish. Parasitological inspections revealed the following infestations: Eustrongylides excisus (Nematoda), Dactylogyrus sp. (Platyhelminthes) and Achtheres percarum, Diplostomum spathaceum (Platyhelminthes) and Trichodina sp. (Ciliophora). The prevalence and intensity of the infection with parasites were varied at age groups of host. Significant differences were found for the white blood cell and lymphocyte in relation to parasitism. Parasitism had no influence on studied blood parameters of S. lucioperca in natural conditions.

Histopathological study of gill, kidney and liver of Persian Sturgeon (Acipenser persicus Borodin, 1897) and Stellate (Acipenser stellatus Pallas, 1811) exposed to sublethal concentration of un-ionised ammonia UAN.

This study was carried out to investigate the histopathological changes of gill, kidney and liver of Persian Sturgeon and Stellate in response to various sublethal concentration of ammonia. The sublethal doses were determined after a lethal pre-test and then the experiment was done in six treatments with three replicates for both species. In Persian sturgeon, the treatments were including 5, 7, 9.7, 13.2, 18 and 25 mg/l ammonia. In stellate, the concentrations of 5, 6.23, 7.76, 9.66, 12.04 and 15 mg/l ammonia were considered as treatments. Also, one group without ammonia was considered as control for each experiment. The histopathological investigations were done after 96 h exposure. According to our observations, a range of histopathological alternations were found in gill, liver and kidney of both examined fish. The alternations of gill tissue were lamellar necrosis, hyperplasia, lamellar adhesion, haemorrhage, swelling of gill lamellae. Severity of these alternations was dose-dependent and was significantly higher in Persian sturgeon than in stellate. The degree of histopathological alternations of liver did not show a regular pattern between treatments in both species. These alternations were hyperemia, bile record, cell necrosis, cell atrophy, fatty degeneration and cloudy swelling. The signs of kidney alternations intensified with increasing of ammonia concentration in both species. The signs such as hyperemia, vision tissue degeneration, cell necrosis, dilatation of Bowman's space. In conclusion, our results showed that ammonia in concentration of more than 5 mg/l have more adverse impacts on gill, liver and kidney tissues.

Parasitic infection alters haematology and immunity parameters of common carp, Cyprinus carpio, Linnaeus, 1758.

The present study was conducted to investigate the effects of parasite infection on haematological parameters of common carp, Cyprinus carpio. To this end, fish with same age were sampled from a warm water fish farm. After fish sampling, fish were transferred to lab for parasite study. Parasite incidence percent and density were calculated for two population carps. After parasite study, to investigate the haematological parameters, the blood sampling was carried out from two group fish i.e. infected (n = 20) and non-infected fish (n = 20). According our results, totally three parasite species were identified including Dactylogyrus sp., Trichodina sp. and Lernaea cyprinacea. Significant differences were observed between infected and non-infected fish (P < 0.05). In this regard, the values of haematocrit, haemoglobin and red blood cell were lower in infected fish than healthy individuals (P < 0.05). In contrast, number of white blood cells (WBCs) were higher in infected fish compared to non-infected fish (P < 0.05). In conclusion, our study reveals that the parasite infection was responsible for altering the haematology of common carp. Increased number of WBC may be in relation to the defense mechanism and immunological responses against parasites.

Changes of haematological indices of grass carp, Ceteopharyngodon idella exposed to monogenean parasites, Gyrodactylus spp. and Dactylogyrus spp.

The present was carried out to investigate the effects of monogenean infection on haematological indices of grass carp, Ceteopharyngodon idella. In this regard, some haematological indices were measured in two adult groups of grass carp including healthy and infected fish. According to our results, the values of red blood cells (RBCs), haemoglobin (Hb) decreased significantly in infected fishes (P < 0.05). In contrast, the white blood cells (WBCs) values increased significantly in infected fishes (P < 0.05). In contrast, the WBC values increased significantly in infected fishes. In conclusion, our results showed that monogenean infection by Gyrodactylus spp. and Dactylogyrus spp. can affects health condition of grass carp through alternation of haematology.

Histopathological and bacterial study of Persian sturgeon fry, Acipenser persicus (Borodin, 1897) exposed to copper sulfate and potassium permanganate.

Persian sturgeon frys were exposed to different concentrations of copper sulfate and potassium permanganate in order to the evaluation of their impacts on bacterial load of skin, gill and surrounding water and also the histopathological alternations of gill tissue. For this purpose, the sublethal doses were determined after a pre-test and then the experiment was done in 4 (for copper sulfate: 0.07, 0.14, 026 and 0.5 mg/l) and 5 (for potassium permanganate: 0.07, 0.14, 026, 0.5 and 1 mg/l) treatments with three replicates inside the glass aquaria. Also, one group without disinfecting drug was considered as control for each experiment. The microbial and histopathological investigations were done after 96 h exposure. According to our results, a range of histopathological alternations were observed in gills tissue including mucus coagulation and secretion, hyperplasia, lamellar necrosis, hyperplasia, lamellar adhesion, haemorrhage, thickening of secondary lamellae, hypertrophy of supporter cartilage, clubbing of gill lamellae and sliming of primary lamellae. The severity of these alternations increased with increasing of the doses of the copper sulfate and potassium permanganate. The bacterial load (CFU/g) of gill, skin and surrounding water was lower in 0.07 mg/l copper sulfate treatment and 1 mg/l potassium permanganate treatment (P < 0.05) than in other treatments. In conclusion, our results showed that the certain doses of the copper sulfate and potassium permanganate have disinfecting effects on bacterial load of gill, skin and surrounding water, although this is along with some histopathological alternations. Also, it seems that the copper sulfate has higher disinfecting power than potassium permanganate.

Occurrence and intensity of parasites in Wels catfish, Silurus glanis L. 1758 from Amirkelayeh wetland, southwest of the Caspian Sea.

Amirkelayeh international wetland with a surface area of 1,230 hectares and fifteen fish species is an important water resource in the southern part of the Caspian Sea. There is few reports on fish parasites of this area. In the present study, a total of 80 Wels catfish, Silurus glanis, were collected from April through July 2011. After recording biometric characteristics, common necropsy and parasitology methods were used. In the present study, a total of 441 individuals of seven parasite species consisting of one nematode: Raphidascaroides sp., one cestode: Triaenophorus crassus, two digenean trematodes: Aphanurus stossichi and Diplostomum spathaceum, two monogenean trematodes: Silurodiscoides vistulensis and Silurodiscoides siluri, and one crustacean: copepodid stage of Lernaea cyprinacea was found in the catfish. The occurrence of copepodid stage of L. cyprinacea, Raphidascaroides sp. and T. crassus are reported for the first time from S. glanis in Iran.

Histopathological and bacterial study of skin and gill of grass carp, Ceteopharyngodon idella, (Valenciennes 1844) exposed to copper sulfate and potassium permanganate.

The gill histology and bacterial load of skin of the grass carp juveniles were investigated in relation to various concentrations of copper sulfate and potassium permanganate. For this purpose, the sublethal doses were determined after a pre-test and then the experiment was done in five treatments (for copper sulfate: 1, 1.94, 3.71, 7.07 and 15 mg/l and for potassium permanganate: 0.25, 0.52, 1.91, 2.27 and 5 mg/l) with three replicates inside the glass aquaria. Also, one group without disinfecting product was considered as control for each experiment. The microbial and histopathological investigations were done after 96 h exposure. According to results, the lowest bacterial load (CFU/g) of skin was observed in 15 mg/l copper sulfate treatment and 0.25 mg/l potassium permanganate treatment (P < 0.05). Also, the histological investigation showed a range of histopathological alternations in gills tissue including lamellar necrosis, hyperplasia, lamellar adhesion, haemorrhage, clubbing of gill lamellae. The severity of these alternations increased with increasing of the doses of the copper sulfate and potassium permanganate. In this regard, the highest histological damages were observed in 15 mg/l copper sulfate and 5 mg/l potassium permanganate respectively. Our results showed that low dosage of potassium permanganate has best effect on reducing of bacterial load of skin with lowest adverse effects on gill tissue.

Investigation of parasites of pikes (Esox lucius Linnaeus, 1785) from Chamkhale River, Anzali and Amirkelayeh wetlands, Iran.

To investigate the health status, the parasite diversity and abundance were studied in three pike populations. For this purpose, totally 90 fish were caught from three natural habitats of pike including Chamkhale River, Anzali and Amirkelayeh wetlands, Iran. After biometry and age determination, fish were dissected and parasites were investigated in intestine, gill and eye. According to results, five parasite species were identified in whole body of pikes including Eustrongylides exises, Raphidascaris acus and Triaeophorus crassus in intestine, Tetraonchus monenteron in gill and Diplostomum spathaceum in eye. The highest values of quantitative indices of parasite population [i.e. incidence percent (86.66 %), mean intensity (60.83 ± 39.92), mean abundance (58.14 ± 34.6) and abundance range (1-232)] were recorded for T. monenteron in all three sampling regions. The lowest values of these quantitative indices were found for D. spathaceum, E. exises and Tetraonchus crassus in Anzali wetland, Chamkhale River and Amirkelayeh wetland respectively. In 2, 3 and 4 years old pikes, T. monenteron had the highest values of quantitative indices of parasite population. In conclusion, our results showed that Anzali wetland have more parasite pollution compared to other sampling regions. This may be due to the more rapid eutrophication in this wetland compared to Amirkelayeh wetland and Chamkhale River.

Stress indices of Grass carp, Ceteopharyngodon idella, (Cuvier and Valenciennes, 1884) change in response to Monogenean parasites pollution, Gyrodactylus spp. and Dactylogyrus spp.

The aim of this research was study of stress indices in response to Monogenean infection in Grass carp, Ceteopharyngodon idella. In this regard, some stress indices were measured in two adult groups of Grass carp including healthy and infected fish. According to our results, the values of cortisol and glucose and lactate were significantly higher in infected fishes than healthy individuals. Elevation of cortisol and glucose demonstrated the existence of stressful condition caused by parasitic infection and demands for energy for adaptation. In conclusion, our results showed that Monogenean infection by Gyrodactylus spp. and Dactylogyrus spp. affects health condition of Grass carp through alternation of stress components.

Dietary Administration of Lactobacillus plantarum Enhanced Growth Performance and Innate Immune Response of Siberian Sturgeon, Acipenser baerii.

We investigated the effects of Lactobacillus plantarum used as a dietary supplement on the growth performance and innate immune response in juvenile Siberian sturgeon Acipenser baerii. Juvenile fish (14.6 ± 2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations [1 × 10(7), 1 × 10(8) and 1 × 10(9) colony-forming units (cfu) g(-1)] and a control (non-supplemented basal) diet for 8 weeks. Growth performance indices were increased in fish fed the 1 × 10(8) cfu g(-1) L. plantarum diet compared to the other groups. There was an increased innate immune response in fish fed the experimental diets. The highest levels of lysozyme activity, total immunoglobulin (IgM) and complement component 3 (C3) were observed in fish fed the diet containing L. plantarum at a concentration of 1 × 10(8) cfu g(-1), but there was no significant difference in the level of complement component 4 (C4) in fish fed the experimental diets or the control diet. The present study underlying some positive effects (growth performance and immune indices) of dietary administration of L. plantarum at a concentration of 1 × 10(8) cfu g(-1) in the Siberian sturgeon.

Hematological parameters associated with parasitism in pike, Esox lucius caught from Anzali wetland.

This study involved 120 pike, Esox lucius, captured from Anzali wetland. Parasite fauna were identified in captured fish. Also, changes of haematological parameters were compared both infected and uninfected fish. Parasitological inspections revealed the following infestations: Skin: Lernea cyprinacea, Argulus foliaceus (Crustacean) and Tricodina sp. (Ciliatea). Gill: Dactylogyrus sp. (Digenea) and Tetraonchus monenteron (Monogenea). Eye: Diplostomum spathaceum (Digenea). Gut: Eustrongylides exises, Rhipdocotyle illense, Raphidascaris acus (Nematode), Corynosoma Strumosum (Acanthocephala). Most prevalence and intensity were related to Eustrongylides exises and Rhipdocotyle illense. Following haematological parameters were evaluated: haematocrit, haemoglobin concentration, erythrocyte and leukocyte counts, mean cell volume (MCV), mean cell haemoglobin, mean cell haemoglobin concentration lymphocytes, monocytes and eosinophils. Significant difference was found for MCV between infected and uninfected fish.

Haematological characteristics associated with parasitism in bream, Abramis brama orientalis.

A parasitological investigation was done on 175 specimens. Infections of A. brama orientalis were analyzed according to the age and sex. The fish also were examined for evaluation changes of haematological parameters in relation to parasitic infection. Four parasites were found, including-Caryophyllaeus laticeps and Ligula intestinalis (Cestoda), Diplostomum spathaceum (Platyhelminthes) and Trichodina sp. (Ciliophora). Among identified parasites maximum prevalence and mean intensity were related to Ligula intestinalis and Caryophyllaeus laticeps respectively. The values of prevalence and mean intensity showed significant differences among ages. Our results revealed prevalence, mean intensity and abundance had not significant difference between males and females. Parasite infection provoked reduction (P < 0.05) in haematocrit, mean cell volume and lymphocyte. On the other hand, significant increase (P < 0.05) in white blood cell (WBC), mean cell haemoglobin concentration and neutrophil in blood of infected fish was observed. Significant differences were detected for the WBC, lymphocyte and neutrophil (infected versus uninfected by Trichodina sp., Diplostomum spathaceum and Caryophyllaeus laticeps). In addition to WBC and lymphocytes, significant change was observed for the haemoglobin (Hb) (infected versus uninfected by Ligula intestinalis).

Long-term effects of intraperitoneal injection of estradiol-17ß on the growth and physiology of juvenile stellate sturgeon Acipenser stellatus.

Juvenile stellate sturgeon Acipenser stellatus were intraperitoneally injected with estradiol-17ß (E2; 0 and 5 mg/kg fish) to investigate the possibility of sex reversal and also determine the changes in biochemical parameters. Five-month-old fish (40.9 ± 1.1 g) were injected every 3-week interval during a 190-day trial. At the termination of the experiment, final weight and other growth parameters including weight gain and specific growth rate, hepatosomatic and viscerosomatic indices were not affected by repetitive injection of E2. Hematological features of E2-treated fish showed significant reductions in number of red blood cells, hemoglobin concentration, hematocrit value and mean corpuscular hemoglobin (P < 0.05), but no significant changes were observed in number of white blood cells, mean corpuscular volume and mean corpuscular hemoglobin concentration (P > 0.05). Calcium, phosphorus, glucose, triacylglycerol, cholesterol, total protein and estradiol concentrations were significantly increased in fish injected with E2 (P < 0.001). Plasma progesterone and testosterone levels were noticeably lower in fish injected with 5 mg/kg E2 rather than the control fish (P < 0.001). Histological observations of gonads showed that all fish injected with 5 mg/kg E2 apparently feminized, while 66.6 % of the control group was female. These results revealed that the injection of E2 is an effective method for feminization of stellate sturgeon without having significant inhibitory effects on growth and survival.