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Observation on the age, growth and somatic condition of Carasobarbus luteus (Heckel, 1843) and Capoeta trutta (Heckel, 1843) (Cyprinidae) in the Tigris River, Turkey
Get PDFThis study was carried out to determine some biological characteristics including age, growth and somatic condition of Carasobarbus luteus and Capoeta trutta in the Turkish part of the Tigris River. The examined samples of C. luteus were distributed between II-IX years of age. The length-weigth relations of females and males were calculated as Log W =-4.7314 +3.0113 Log FL and Log W = -4.7631 +3.0263 Log FL respectively. Von Bertalanffy growth equations were estimated as Lt=40.09 [1-e^-0.087036 (t+1.55004)] for females and Lt=38.14 [1-e^-0.080056 (t+2.34838)] for males. The somatic condition was 1.9667 ± 0.1751 for females and 1.9967 ± 0.4205 for males. The observed samples of C. trutta were distributed between I-VI years of age. The length-weigth relationship of females and males were calculated as Log W = -4.6845 + 2.9303 Log FL, Log W = -4.7784 + 2.9746 Log FL, respectively. Von Bertalanffy growth equations were estimated as Lt=35.36 [1-e^-0.082817 (t+4.82738)] for females and Lt=28.82 [1-e^-0.12380 (t+4.40235)] for males. The somatic condition in female and male individuals were determined as; 1.4434 ± 0.1682 and 1.4722 ± 0.1984 respectively. Both species are economic fish in the Tigris River. Biological characteristics of the species determined in the present study, may contribute to a better understanding of the life cycle, thus providing useful data for its conservation and management
Spatial and temporal patterns of benthic macrofauna in Gorgan Bay, south Caspian Sea, Iran
Get PDFWe quantified the distribution, abundance and assemblage structure of macrofauna at 22 stations in Gorgan Bay, seasonally in 2012-2013. Also, depth, temperature, salinity, DO, TOM and sediment particle size were measured in each station. The highest concentration of TOM was measured near the western littoral zone (10.22) while the mouth part and north-eastern area was characterized by the lowest values (2.65 % and 4.69). A total of 31658 individuals belonging to 12 families and 14 species were identified. Polychaeta with 3 species was the most dominant group in terms of abundance. The four most abundant taxa making up 85% of all specimens were Streblospio gynobranchiata, Tubificidae, Hediste diversicolor and Abra segmentum. The maximum density (7,893 ind/m^2) was obtained at station 1 while the minimum (1,777 ind/m^2) was observed at station 16. The western area was characterized by the highest species diversity (H', 1.94) and the stations 10, 8 and 7 were characterized by the lowest diversity indices (H', 0.72, 0.77 and 0.87, respectively). The PCA showed that water parameters with more temporary variations had a greater significance in explaining the system variability, and a not marked but evident difference between the two parts of Gorgan Bay was observed and supported by nmMDS test. So Gorgan Bay presents transitional macrobenthic assemblages that are spatially distributed along substrate gradients but it seems that the coastal ecosystem of the south Caspian Sea and mouth-eastern part of Gorgan Bay is very dynamic and some species are forming a metapopulation toward western sites
Discriminating mesozooplankton communities in Bushehr marine coastal ecosystems- Persian Gulf
Get PDFCoastal ecosystems of Bushehr are shallow environments subject to human impacts, including shrimp aquaculture and urban expansion activities. A spatial-temporal study was conducted in order to assess the actual ecological status of the creeks, estuary and marine sites on the basis of their taxonomic composition and density of mesozooplankton. Zooplankton species distribution and abundance data at 6 sampling sites during June 2015 - March 2016 revealed 24 taxa represented by 5 divergent groups. During the study period, high salinities (around 35-47) were recorded, characterizing all systems as a coastal-marine ecosystem, rather than true estuarine. The mesozooplankton assemblage was characterized by the dominant marine Copepod, Labidocera sp., zoeas of coastal/marine crab, Ilyoplax frater, marine copepod Acartia fossae and a marine pelagic tunicate, Oikopleura dioica. Copepods were the main dominant group and Labidocera sp the most abundant species, with high abundances in winter, whereas high abundances of the Ilyoplax frater were noticed in summer. Based on SIMPER analyses, highest dissimilarity was observed between Ramleh and Lashkary and discriminating taxa for all sites were Labidocera sp followed by Ilyoplax frater contributing to more than 68% of the total average dissimilarities for all locations. The multivariate BIO–ENV procedure indicated that Labidocera sp. followed by Acartia fossae strongly correlated to the variability of depth, transparency and salinity. Finally the results showed that temporal and spatial variation in the mesozooplankton community is consistent with the dynamic character of the habitat characterized as a typical coastal marine system (with low average depths, transparency and high salinity)
Dietary thyme essential oil (Thymus vulgaris) changes serum stress markers, enzyme activity, and hematological parameters in gibel carp (Carassius auratus gibelio) exposed to silver nanoparticles
Get PDFGibel carp (Carassius auratus gibelio) juveniles with an average weight of 8.73± 2.1 g were fed a basal diet (control) and three experimental diets (T200, T400 and T800), containing 200, 400 and 800 mgkg^-1, respectively of thyme essential oil (Thymus vulgaris) for six weeks. After six weeks feeding trial, both control and thyme essential oil-added feed groups were exposed to sub-acute toxicity of silver nanoparticles (Ag-NPs) for a period of 96 h. At 96 h after exposure, the number of erythrocytes (RBC), leucocyte (WBC), hematocrit (Hct), hemoglobin (Hb), the differential leukocyte count in blood and alanine aminotransferase (ALT), aspartate aminotransferase (AST) activity, HDL-cholesterol, LDL-cholesterol, cortisol and lactate in serum were measured. The results revealed feeding a thyme essential oil diet significantly conferred resistance to oxidative stress with sub-acute toxicity of Ag-NPs. Thyme essential oil enhanced the RBC and WBC count, hematocrit and hemoglobin content, at both low (T400) and high doses (T800). Biochemical analysis showed that serum ALT and AST activities, and LDL-cholesterol in the thyme essential oil-added feed groups were significantly reduced with increasing dietary thyme essential oil. Plasma HDL-cholesterol was significantly elevated by a high-dose of dietary thyme essential oil (T800). Furthermore, cortisol and lactate levels in serum significantly decreased throughout the thyme essential oil-added feed groups compared to the control. In summary, the use of thyme essential oil at 400 and 800 mgkg^-1, as dietary supplements, has potential to decrease oxidative stress of gibel carp providing resistance to non-fatal effects of pollutant by Ag-NPs
Acute toxicity of TiO2, CuO and ZnO nanoparticles in brine shrimp, Artemia franciscana
Get PDFThe brine shrimp, Artemia spp., is widely used in ecotoxicological research as a biological index. In the present study, aquatic stability and acute toxic effects of TiO2, CuO and ZnO nanoparticles (NPs) on Artemia franciscana were investigated. Acute exposure was conducted in sea water with different concentrations of selected nanoparticles at 24h, 48h, 72h and 96h. The mortality rate of A. francisca increased significantly with increasing concentrations and duration of exposure of all NPs. The toxicity pattern of metal oxides to A. francisscana was as follows: CuO>TiO2>ZnO. Our results point to the fact that both TiO2 and ZnO NPs exhibited moderate toxicity to Artemia larvae in 24h as compared with CuO, regardless of their size and concentrations
Short communication: Population genetic structure studies of Liza aurata based on mtDNA control region sequences analyses in the southern coasts of the Caspian Sea
Get PDFNowadays many species are endangered as a result of habitat loss. Decreases in population lead to reduced genetic diversity, which can cause survival crisis in a population (Cecconi et al., 1995). Nowadays optimal management of fish stocks needs information on population structure of species that is provided to researchers through genetic science. Bereavement of science about stock composition will lead to the fracture of fisheries management and unsuitable harvest of stocks (Papasotiropoulos et al., 2007). One of the beneficial methods to demonstrate genetic diversity is haplotype analysis of the D-loop region, an index which is very important and determinant for the preservation of species. Significant genetic variation is found in the D-loop region, even among individuals within a given species. Grey mullets are not endemic species of the Caspian Sea. Juveniles of L. aurata, L. saliens and Mugil cephallus were introduced from the Black Sea into the Caspian Sea during the years 1930-1934. But only the introduction of L. aurata and L. saliens was successful and they adapted well to the ecological conditions of the Caspian Sea (Fazli et al., 2008)
Effect of Lactobacillus plantarum and Lactobacillus delbrueckii subsp. bulgaricus on growth performance, gut microbial flora and digestive enzymes activities in Tor grypus (Karaman, 1971)
Get PDFIn this study, two main probiotics (Lactobacillus plantarum and Lactobacillus delbrueckii subsp. bulgaricus) were isolated from the intestine of Tor grypus and their effects on growth performance, gut microbial flora and digestive enzymes activities (i.e., α-amylase, lipase, trypsin, chymotrypsin, and alkaline phosphatase) of Tor grypus (Karaman, 1971) were determined. Juveniles of T. grypus (n=480, weighing 45±10 g) were randomly divided into 4 equal groups (with 3 replications) and fed on diets containing 5×10^7 cfu g^-1 of L. plantarum (G1), L. bulgaricus (G2), L. casei (G3) and a control diet (without probiotic) for 60 continuous days. Results showed that probiotic supplementations had generally significant effects on growth performance (p<0.05). The G2 group had the best effect on specific growth rate (SGR) and feed utilization efficiency in T. grypus. The digestive enzyme activities, on day 30 after feeding, significantly increased in G1 when compared with those in the control group (p<0.05). Significant changes in bacterial intestinal flora were observed in all probiotic groups compared with the control (p<0.05). Our results indicated that supplementation of isolated bacteria from the intestine of T. grypus (i.e., G2) can efficiently improve growth performance, intestinal microbiota and some digestive enzyme activities in juvenile T. grypus. Therefore, it can be isolated and used as a growth enhancer just like the commercial probiotics
Prevalence and effects of Lernaea cyprinacea (anchor worm) on the growth, skin histopathology and hematology of Catla catla
Get PDFThe experiment was conducted to evaluate the prevalence of Lernaea cyprinacea and its effects on growth, hematology and skin histopathology of Catla catla in four experimental earthen ponds (P1, P2, P3 and P4) for 90 days. The growth performance, prevalence of Lernaea cyprinacea and ulceration was recorded on a fortnightly basis. The highest final body weight was observed in P4 (413.7 g) followed by P2 (378.7 g) and P1 (359.8 g) compared to P3 (357.8 g). Increase of Lernaea cyprinacea infection in the first half of the study was from 20.51% - 36.25% in P1, 17.75% -25.25% in P2, 6.5% - 10% in P3 and 14.75% - 13.1% in P4. Ulceration percentage in fish was significantly higher during August and September than May to July. Histopathological studies of skin showed a huge difference between healthy and infected fish skin. Hematological parameters such as hemoglobin (Hb), total erythrocytes count (TEC), total leukocyte counts (TLC) and packed cell volume (PCV%) of non-infected fish exhibited significantly higher values than that of infected fish. Other parameters like erythrocytes sedimentation rate (ESR), neutrophils, eosinophils, lymphocytes, basophils, monocytes and thrombocytes of infected fish showed significantly higher values than those of non-infected fish. In conclusion the exposure to parasites illustrated significant decrease in the Hb, TEC, TLC and PCV% and increase in ESR and other blood cells concentration showed significant severity of parasitic infection
Short communication: The comparison of fatty acids, fat-soluble vitamins and cholesterol in the muscle of wild caught, cage and pond reared rainbow trout (Oncorhynchus mykiss W., 1792)
Get PDFFish meat is a good source of fats, proteins, vitamins and minerals. Therefore, it is an important component of a balanced diet for humans (Stancheva et al., 2010). Fish store the lipids in various organs, particularly in muscles and liver. Somatic muscle is the dominant tissue in fish and constitutes more than 60% of the live fish weight. Fatty fish such as salmonid mainly deposit lipids in their muscle (Love, 1980). Lipids are important components of fish diets due to their role in providing energy and essential fatty acids, as they carry of fat-soluble vitamins, and resource of polar lipid including sterols, which are important structural compounds of cell membranes (Görgün and Akpınar, 2007). Recently, there has been heightened interest in the lipid and fatty acid (FA) composition of fish. Fish naturally contain high levels of polyunsaturated fatty acids (PUFA) that are recognized as essential biochemical components of the human diet because of their beneficial effects for human health (Sushchik et al., 2007). Recent studies have shown that n-3 PUFAs play a vital role in the prevention and treatment of cardiovascular disease, inflammation, aggression, depression, hypertension, autoimmune disorders and cancer. Along with omega-3 and omega-6 fatty acids play a crucial role in brain function as well as in normal growth and development
Study of gill and kidney tissue changes in Tenualosa ilisha during migration from sea to the Karun and Bahmanshir Rivers
Get PDFIn this research, histological changes of gill and kidney, as a basic and important organ in osmoregulation, during migration from Musa creek to Karun and Bahmanshir Rivers was studied. Ten fish from each station of Persian Gulf, Karun and Bahmanshir with similarity in biometric of size and weight were collected. After fixation in Bouin's solutions, routine procedure of tissue preparation was done and 6 μm sections stained with Hematoxylin and Eosin, studied by optical microscope equipped with a daynolit lenses. The greatest number and area of chloride cells were seen in sea samples but they decreased during migration to Karun and Bahmanshir Rivers (p0.05). In kidney, during migration from the sea to the river, the diameter of proximal and distal lumen increased. But in Karun samples, diameter of lumen of distal tubules were higher than others station. Also, there was no significant difference in other tubule between in Karun and Bahmanshir samples. Therefore according to this study, gill and kidney have active participation in osmoregulation. This fish can be a good model for study of osmoregulation in different salinities because of adaptation and response to different environmental salinities in gill that associated with histologic changes