Survey of diplostomiasis in Sturgeon fingerling

In parasitologic survey on sturgeon fish in Shahid-Beheshti farm, the metacercaria of Diplostomum spathaceum were seen in the lens of fish fingerlings. The prevalence of infestation was 22 percent. The infestation with this parasite was one of the reasons of body lose weight and mortality. Observations showed that the ratio of the body weight loses directly depend on the number of metacercaria. During the study two different families of intermediate hosts include; Limneidae and Physidae were identified. The frequency of Physidae is more than Limneidae

Identification of boneless parts in silver carp (Hypophthalmicthys molitrix) fillets

The silver carp (Hypophthalmicthys molitrix) comprises about 50% to 85% of the composition of fish species in the polyculture system of warm water species in Iran. However, the difficulty in preparation of this species and the presence of pin bones are among the main reasons to restrict the demand of this species in the domestic markets, particularly in non-coastal province s. The objective of this study was to identify parts with less and/or no bones in silver carp fillets. The shape, size and location of bones found in the flesh were studied by three methods: Enzyme digestion, cooking in hot water and X-ray scanning. Results showed that except vertebral bones and ribs, the thin bones found in different parts of the flesh can be categorized into three groups: Pinshaped, Y shaped and non-regular shaped (several bifurcations). On the basis of density and arrangement of bones, we found that the fillets are made up of three d different layers: External layer mostly of dark muscles and lipids with no bones, middle layer with the highest density of bones and the internal layer which comprises about one third of the depth of fish flesh. The shape and arrangement of the bones in fish tail was significantly different. On the basis of recent findings, the deep part of the back and a narrow band on the upper part of the back are considered as boneless parts in silver carp

PUFA content of silages prepared from tuna cannery wastes

Ensiling as one of the best methods for utilization of tuna wastes was investigated. docosahexaenoic acid [DHA C22:6(n-3)]- rich products were obtained from the wastes (viscera and dark meat) of four tuna species, namely longtail, skipjack, yellowfin and kawakawa by a procedure involving ensiling in organic acids followed by neutralization. Identification of fatty acids in the samples was performed by comparison with chromatograms of fatty acids standard. Total lipid content of silages varied from 10.41% in skipjack dark meat silage to 22.01% in kawakawa viscera silage, but all lipids contained high percentages of DHA and EPA [eicosapanteoneic acid C20:5(n-3)]. The highest DHA ratio (15% of total lipids) was found in the lipid of skipjack viscera silage and the highest ratio of EPA (11% of total lipids) belonged to the lipids of kawakawa dark meat silage. ANOVA test results indicated that DHA ratio was significantly high before silage preparation and linolenic acid [C18:3(n-3)] content significantly differed between the species (p<0.05)

Determination of chemical and biochemical composition of Artemia uramiana cyst shells and its extraction chitin

Artemia urmiana cyst shells collected, purified and dried from ashore of Rashkhan and Bozorgrah in the Urmia Lake in January and February 2002. According to the results obtained by standard methods of analyses the cyst shell contains: 4.8±0.5% lipid, 32±2% protein, 10.5±1.0% moisture, 0.5±0.2% haematin and 20.6±2.0% total ash. The chemical composition of ash are: Na2O 1.98%, MgO 1.14%, S03 6.82%, CI 3.23%, K20 2.12%, CaO 4.05%, Fe2O3 1.68%, Zn 0.05%. The chitin was extracted from Artemia cyst shells by using different methods of demineralizaion, delipidization, deproteinization and decolorization. The yield of extraction from cyst shells was 28±3%. Composition of chitin was determined by FTIR, X-Ray Powder diffraction and C.H.N.O analyser. Artemia urmiana cyst shell contains approximately about 28±3% percentage chitin

Comparison of produced fish protein hydrolysate from viscera and head of silver carp (Hypophthalmichthys molitrix) using alcalase enzyme and internal tissue enzymes

In the present study, hydrolysed protein of viscera and head of Silver carp (Hypophthalmichthys molitrix) was compared using Alcalase enzyme and internal tissue enzymes at 2 and 4 hours. The result indicated that product by Alcalase (Treatment 1) had significantly higher protein and rate of hydrolysates than that produced by internal tissue enzymes (Treatment 2). So, the highest mean (±SD) protein (68.10±1.33) was related to treatment 1-head (with Alcalase enzyme) after 4 hours and the highest rate of hydrolysates (29.36±1.35) was related to treatment 1-head (with Alcalase enzyme) after 4 hours. The result indicated that rate of hydrolysates raised as time of hydrolysates increased. However the intensity and rate of hydrolysates is reduced. The highest rate of hydrolysates occurred at 120 minutes in the first. This mode was similar for two treatments. The result can be considered as the Alcalase was preferred to internal enzyme

Chitinase isolated from water and soil bacteria in shrimp farming ponds

Chitinases have received attention because of their wide applications in the medicine, biotechnology, agriculture, waste management and industrial applications such as food quality enhancer and biopesticide. Excessive use of insecticides has led to several problems related to pollution and environmental degradation. In this study, isolation and identification of native bacterial strains with chitin hydrolysis activity, took place from water and soil of shrimp culture ponds in Bushehr and Abadan. To investigate the capacity of our chitinase for using in insecticide, biochemical properties of selected chitinase obtained in this research were compared to that of produced by Bacillus cereus p-1, isolated from an insecticide tablet. In this research, three mesophilic strains containing: Serratia marcescens B4A, Citrobacter freundii B1A and Bacillus cereus B3R were isolated. Results showed a 1600 bp band corresponding to chitinase gene. The similarity between temperature and pH profile and stability of chitinase was extracted from native bacteria and ones was obtained from Bacillus cereus p-1 implied that chitinase extracted from Serratia marcescens B4A has potential application in industry

Population genetic structure of Persian sturgeon (Acipenser persicus) between South Caspian Sea and Sefidrud River using DNA sequencing method

The goal of this study was to analyse the population genetic structure of the Persian sturgeon (Acipenser persicus) between South Caspian Sea and Sefidrud River with mtDNA control region (Dloop gene) and DNA sequencing method during 2010 – 2012 sturgeon stock assessment project. Fish speciemns were collected by bottom trawl net. Extraction of DNA, PCR and DNA sequencing were carried out. Diversity index, the gamma distribution shape parameter for the rate heterogeneity among sites and nucleotide sequence, Fst index, exact test, the historical demographic pattern using neutrality tests and mismatch distribution analysis (D test of Tajima and Fs test of Fu) were analysed. Thirteen haplotypes were obtained, average (±SD) for haplotype diversity was 0.961 ± 0.101, nucleotide diversity was 0.038 ± 0.015, the gamma distribution shape parameter was 0.19, Fst index revealed little genetic structure between populations and the significant Fst value was seen by 10000 permutation only between Sefidrud River and Other Areas (P≤ 0.05) and was confirmed by exact test of population differentiation. Mismatch distribution for Acipenser persicus appeared to be unimodal, which closely matched the expected distributions under the sudden expansion model and supported by the low Harpending’s Raggedness index (0.061). Tajima’s D and Fu’s Fs statistics were -0.84 and - 0.220, respectively, and was not significant. The results of this study showed that the population of Acipenser persicus in Sefidrud River were genetically differentiated from South Caspian Sea and three other areas represented a single panmictic populations. Therefore, fisheries managements of this valuable species should be directed towards conservation of gene pools and increasing different populations

Comparison of antibiotics and bacteriocins antibacterial activity on Xanthomonas citri subsp.citri

Citrus canker is a citrus disease species created by the bacterium Xanthomonas citri subsp.citri. Many citrus, such as oranges, lime, and grapefruit are affected by the infectious bacteria and stems, leaves and fruits are experiencing loss. In this experiment antibacterial effects of five kinds of antibiotics including ampicillin, kanamycin, chloramphenicol, penicillin, streptomycin, Cronobacteriocin DGH2 and Enterobacteriocin DGH4 were evaluated on 107 strains of Xanthomonas citri subsp.citri. MIC and MBC data for antibiotics and bacteriocins against Xanthomonas strains were performed. According to this project, Xanthomonas strains were comparatively susceptible and resistant to Cronobacteriocin DGH2, Enterobacteriocin DGH4, ampicillin, kanamycin, chloramphenicol, penicillin and streptomycin. NIGEB-183 strain is the most sensitive to these antibiotics and bacteriocins. However, only the NIGEB-242R1 strain is resistant to chloramphenicol. Penicillin has minimum inhibitory effects on Xanthomonas strains. Based on this case study, chloramphenicol is the most antibacterial activity among antibacterial agents and this compound is a good candidate for inhibitory activity. Cronobacteriocin DGH2 has a moderate antibacterial activity against Xanthomonas strains

Road map for developing fish processing industries

Fish per capita consumption in the world is 18.8 kg. The value of fish consumption per capita in Iran has reported 9.1 kg. Comparing to the other countries the fish consumption in our country is very low. Therefore the government organizations are going to increase the fish consumption per capita. There are many ways for increasing the fish consumption that can be considered by the countries. Developing the fish production, producing the new fish products, good marketing and trading are the some of the ways. For the achievement to this objective, a comprehensive program should be planned. In seafood consumption the safety of the food is very important. This matter should also be considered by the consumers. Addition of using the fish as food, the aquatics organisms are very interested for producing the biological products. The road map for developing fish processing industries layout is designed for achieving to these proposes. The road map layout were included three chapters. Road map of fish processing, aquatics organism’s biological products, healthy and safety fishery products. The road map of the fish processing chapter is focused on dissolving the fish processing development problems. The road map of seafood healthy and safety products chapter is researched on identify the related problems and making some suggestions for removing the problems. The road map chaoter on aquatics biological products is subjected on preparing the program for producing the different biological products in pilot plan and industry scale

Assessment of acute effects of Streptococcus faecium on some hematological and histopathological parameters in juveniles rainbow trout (Oncorhynchus mykiss)

Streptococcosis is one of the most important bacterial diseases in cold water fish because of its rapid outbreak specially in summer, relatively high morbidity and mortality, productive reduction and economic losses in aquaculture industry. However, it would be necessary to determine of 50% lethal dose (LD50) of bacteria (Streptococcus faecium) and studying its acute effects on hematological and histopathological parameters. For measuring LD50 five dilutions of bacteria were obtained by Macfarlane method and the fish were injected by intraperitoneal (IP). The experience was carried out in 6 treatments and 3 replicates. The fish were injected by LD50 dose and after 10 days, samples of blood and tissues including: Eyes, brain, kidney, liver and gills were collected. The injected fish showed darkening of body, exophthalmia, abdominal distension and prolapsed anal. The obtained results showed significant reduction (P<0.05) in level of red blood cells (RBC), hemoglobin (Hb), hematocrit (Hct) and significant increase (P<0.05) of mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) in test group compare to control group. In addition histopathological findings including hemorrhage in brain, eyes, kidney and liver, congestion in liver, brain and gills, inflammation of gills, meningitis and separation of menangial layers, presence of melanin pigments and increasing of mucus cells in the comial epithelium and were showed shrinkage, bowmans space dilation, degeneration and vacoelation in tubular cells, increasing of melanomacrofage centers and melanin pigments in kidney