Sustainable Aquaculture and Health Management Journal
Volume:1 Issue: 1, Winter and Spring 2014

This study was conducted to evaluate the efficiency of Ergosan, an algal extract containing alginic acid and Hilyses, a fermented Saccharomyces cerevisiae, on growth, immune response and hematological parameters in rainbow trout (Oncorhynchus mykiss). Fish with an initial average weight of 70-75 g were fed with Ergosan (5 g kg-1) and Hilyses (10 g kg-1) for a period of 70 days. The Results revealed that dietary supplementation of Ergosan and Hilyses enhanced the growth of all treated fish significantly compared to fish fed with non-supplemented diet. Dietary intake of Ergosan significantly increased the red blood cell, white blood cell and neutrophil levels compared to the Hilyses-fed and control groups.The highest IL-8 level and lysozyme activity were recorded in the Hilyses-fed fish followed by Ergosan. Serum total protein content was enhanced in fishes administrated with Ergosan compared to the control group. The findings of this study suggested the potential of Ergosan and Hilyses to activate growth performance and immunological parameters in rainbow trout.

This study was conducted to examine in vitro antibacterialpotential from seed methanol extract of Peganum harmala (L) against some fish pathogenic bacteria including Lactococcus garvieae, Aeromonas hydrophila, Yersinia ruckeri and Pseuodomonas putida isolated from diseased rainbow trout (Oncorhynchus mykiss). The antibacterial activity of extracts was evaluated using disc diffusion assay, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). MICS were measured by serial dilution and the microplate assays. Results showed that the methanol extract of P. harmala was bactericidal for all test acteria. The MICs of extract using serial dilution and microplate method were 0.6 mg mL-1 and 0.312 to 0.625 mg mL-1 against P. putida and 0.8 mg mL-1 and 0.625 to 1.25 mg mL-1 against L. garvieae, A. hydrophila, Y. ruckeri, respectively which was confirmed by MBC determination. Thus, the antibacterial activity of seed extract of P. harmala can be comparable as an alternative in the control of infectious by these Microorganisms.

The effects of four different levels of wood betony (WB) (Stachys lavandulifolia Vahl) extract (0, 2, 4 and 8% W/W in the diet) were investigated on some serum enzymatic activities and acute stress response of juvenile common carp (Cyprinus carpio). After 10 weeks post feeding, two groups of fish (0 and 8% WB) were subjected to handling and crowding stress and the stress responses including serum cortisol, glucose and some electrolytes (Na, K and Ca) levels were assayed. The results revealed that the fish fed on 8% WB had significantly lower levels of lactate dehydrogenase (LDH) and alanine transaminase (ALT) compared to the control group (P 0.05). The potassium and calcium levels showed insignificant fluctuations post stress (P>0.05). Dietary inclusion of WB seems to improve liver function and response to acute stress in juvenile common carp.

Sublethal toxicity effects of diazinon on the structure of some organs of great sturgeon ( Huso huso ) were investigated. Diazinon was applied at a sublethal concentration of 1.5 mg L -1 at 22±1 ºC for nine weeks as a constant bath. Tissues of liver, kidney and gills were sampled and examined histopathologically after 1, 14, 28, 42 and 63 days post exposure to the toxicant. The results of light microscopic examinations of tissues revealed congestion of blood vessels, pyknosis and cloudy swelling in hepatocytes. Congestion of blood vessels and thickening of the basal membrane of bowman capsule in glumerol of the kidney were also observed. The gill of fish exposed to toxicant also showed congestion and dilation of blood vessels, swelling of the basement membrane, hyperplasia, fusion and necrosis of lamellae. This data showed that a long term exposure of fish to diazinon can cause several pathological changes in respiratory organ, haematopoietic tissues and liver.

The stocks of Caspian roach ( Rutilus rutilus ), an economically important species in the Caspian Sea, is depleting. Annually, millions of fingerlings of these species are produced artificially and restock in the mouth of Qare Soo River in the Southern Caspian Sea, where they exposed to the pesticides coming from rice and orchard farms in the region. The fate of this exposure in hypo-osmoregulatory ability of juvenile fish is important. Therefore, this study initially investigates fingerlings of Caspian roach which was exposed to different concentrations of diazinon (close to estuaries concentration) for 96 h, then they were transferred to the brackish water for 240 h where the growth and survival rate were examined. The major changes in the exposed fish gills to pesticides were collapsed secondary lamellae, oedema, epithelial lifting, and shortening of secondary lamellae. The findings of this study showed decrease of tissue damage in the gill tissue in fingerlings at brackish water, while, a lower growth rate was seen compared to the control group (P

The effects of water current increment on rainbow trout ( Oncorhynchus mykiss ) culture were investigated during a 35 day experiment. Fish weighing 5.5 g were stocked in aquarium tanks. Four different water speeds (0, 3.5, 7, 10.5 cm/s) were provided for each treatment in three replicates. These different currents water were provided by reusing outlet water of each culture unit. Length, weight, daily growth rate (DGR), specific growth rate (SGR), condition factor (CF) and survival rate (SR) were evaluated in each treatment. Also, the changes of NO2, NO3, NH3, NH4, total hardness and pH were measured. The data variance analysis showed significant differences among all treatments during the first week (P

In the present study, the effect of the high and low virulence S. iniae strains on oxidative activity and cytotoxic effects of trout spleen macrophages were studied. Spleen macrophages were collected from trout. Luminol was used as chemiluminigenic probe. Phorbolmyristate acetate (PMA) also was used as positive control activating agent of respiratory burst and significantly stimulated production of reactive oxygen species (ROS) by normal macrophages. Sensitivity of S. Iniae strains to H2O2 and cytotoxicity of bacterial strains for trout macrophages was also determined using the antibacterial effect of H2O2 and the release of lactate dehydrogenase from infected macrophages, respectively. The low virulence strain was killed approximately 6 times more by H2O2 compared to the high virulence strain. Results indicate that, high virulence in S. iniae appears to be correlated with higher macrophage cytotoxicity and resistance to ROS.

In this study, the hematological and growth performance of beluga (Huso huso) fed with herbal supplemented diet were studied. Dietary treatments were control (normal diet), 1 g garlic(Allium sativum)and 1 g nettle (Urticadioica) per 100g feed for 60 days. No significant difference was observed in growth performance between the groups(P>0.05). MCV increased significantly in nettle group compared to control group after 60 days (P

To assess the hygienic conditions of market rainbow trout (Oncorhynchusmykiss ), the residuals of three antibiotics consisting of oxytetracycline (OTC), enrofloxacin (EN) and erythromycin (ET) were measured in the muscles of freshly caught fish obtained from 17 trout farming in Charmahal-va-Bakhteyari (CVB) province using high performance liquid chromatography. Totally 266 fish samples were randomly obtained and 798 muscle samples were used for detection of the above antibiotics. The obtained results showed that OTC was detected in one fish farm (5.8%) having a residual of 0.75 to 7.13 µgg-1. EN was detected in 6 fish farms (35%) with a residual of 0.5- 0.73 µgg-1. Also, the lowest and highest residuals of ET were 23.38 and 181.38 µgg-1, respectively in 5 fish farms (29.4%). The obtained results showed that the residual of these antibiotics in trout muscles of some fish farms were higher than the acceptable levels and therefore, requires a serious attention of both the environment and the consumer health care. Also, the detection limit of 0.05 µgg-1used for these antibiotics shows that application ofhigh performance liquid chromatography method used here in this study is a useful tool for a routine screening of these antibiotics in trout farming.

The present studywas carried out to survey ectoparasites fauna of gold fish (Carassius auratus) in Mazandaran province (Iran) from April 2009 to March 2010. A total of 200 samples were obtained from 10 ornamental fish supply centers and transferred alive to the laboratory. In this study, the following ectoparasites were isolated: Ichthyophthirius multifillis , Trichodina spp., Gyrodactylus spp., Dactylogyrus vastator, Dactylogyrus baueri and Argulus coregoni. The results revealedthat 28.5% of sampled goldfish were infested with ectoparasites .The frequency of protozoan infestations were 15% (9%I. multifillis and 6% Trichodina spp.), the frequency of monogenean ectoparasite was 12.5% (5% Gyrodactylus spp., 5% D. vastator and 2.5% D. baueri) and that of crustaceans (A. coregoni) was 1%. The most frequently reported infestation was due to I. multifillis causative agent of white spot disease.Enhancing the health management through improving water quality and bio-security is the most effective way to prevent the parasite infestations.