A nutrition trial with meagre, Argyrosomus regius was assessed to determine the effect of dietary replacement of fish oil (FO) by soybean oil (SO) on the growth, feed utilization, body composition, fatty acid composition and basic haematological parameters. Six isonitrogenous (47% crude protein) and isoenergetic (gross energy 22 kJ/g) experimental diets were formulated by replacing 0 (FO), 20 (S20), 40 (S40), 60 (S60), 80 (S80) and 100 (S100) % of the FO with SO. Fish were fed three times daily to near satiation for 14 weeks. The specific growth rate (SGR) of fish fed S100 diet was significantly lower than the other treatments, except SO80 diet. The fish fed SO100 diet displayed significantly higher feed conversion ratio than that of other diets (P < 0.05). It was observed that fish fed the SO100 and SO80 diets displayed haemoglobin (HGB) levels significantly lower (P < 0.05) than fish fed the SO20 diet. Packed cell volume (PCV) of fish fed SO20 diet was significantly higher compared to SO100. The white blood cell (WBC) and red blood cell (RBC) remained unaffected by dietary treatment. The docosahexaenoic acid (22:6n-3, DHA) and eicosapentaenoic acid (20:5n-3, EPA) levels of meagre were significantly reduced by the substituting of dietary SO by FO at the end of the feeding period. The level of linoleic acid (18:2n-6, LA) and linolenic acid (18:3n-3, LNA) significantly raised in fish fed with SO diets (P < 0.05). The results of this study showed that SO could be replaced FO up to 80% in meagre diet without negative effect on growth performance and basic haematological parameters. Furthermore, the maximum level of FO replacement with SO determined by second order polynomial regression analysis, was 30.1% on the basis of maximum SGR.

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Economically important sparid fish species, gilthead (Sparus aurata) and white seabream (Diplodus sargus) (Sparidae) are frequently parasitised by diplectanid monogeneans, known to induce severe losses in farming conditions. We have analysed population dynamic of two diplectanid species, Lamellodiscus echeneis and Lamellodiscus ignoratus (Monogenea: Diplectanidae) collected from two bream species in the Beymelek Lagoon (southwest coast of Turkey), comparing it between different host variables (fish size, age and sex) in order to have insight in parasites' ecology, important for managing parasitosis in the intensive aquaculture system. In seabream (N = 127), L. echeneis prevalence was 46.5 % (exact 95 % confidence limits 38.90-54.14), mean abundance 5.64 (bootstrap 95 % confidence limits 4.20-7.65) and mean intensity 12.14 (bootstrap 95 % confidence limits 9.49-15.59). In white seabream (N = 102), L. ignoratus prevalence was 24.5 % (exact 95 % confidence limits 16.53-34.03), mean abundance 1.73 (bootstrap 95 % confidence limits 0.98-3.21) and mean intensity 7.04 (bootstrap 95 % confidence limits 4.60-11.40). Parasites' parameters differed only between seasons in both hosts and between age categories in gilthead, but not in white seabream.

IntroductionThicklip grey mullets, Chelon labrosus (family Mugilidae), are commonly found from the coastal regions of the eastern Atlantic, Scandinavia, and Iceland to southern Senegal and the Mediterranean Sea and southwestern Black Sea. They live inshore, in brackish lagoons and fresh water, and they tend to move northward in the summer as the temperature rises. Little is known about the parasitic fauna of C. labrosus. To our knowledge,

Three species of cyprinids, i.e., Capoeta antalyensis (n = 112), C. caelestis (n = 99) and C. angorae (n = 178) were collected from the Anatolian Region of Turkey to carry out this investigation. A total of 389 specimens of Capoeta were examined for Allocreadium isoporum infections throughout the four different seasons of 2012. The prevalence and mean intensity of infection of A. isoporum was investigated in relation to the host species, the seasons across the year, host size, and sex. Two-hundred and twenty-two specimens of a trematode identified as A. isoporum were found in these fishes. Onehundred seventy-eight C. angorae were caught, and 70 A. isoporum were recorded in 8 of 178 fish examined, with prevalence and mean intensity of infection of 4.49% and 8.7% parasites per infected fish, respectively. In the 112 specimens of C. antalyensis, 73 individuals of A. isoporum were found, with a prevalence of 19.6% and a mean intensity of 3.3. As for the infection in C. caelestis, a total of 79 specimens of A. isoporum were found in 17 of the 99 fish examined, with prevalence and mean intensity of infection of 17.1% and 4.6%, respectively. Prevalence and mean intensity values in relation to host size and sex, as well as the seasonality of infections was analyzed and the results were compared with other studies. The trematode A. isoporum is reported for the first time parasitising three endemic species of Capoeta spp. in Turkey, adding to the knowledge of geographical distribution and host range of this trematode species.

In this study, the total protein and lipid contents and fatty acid composition of endemic freshwater fish Capoeta antalyensis was investigated according to the variation in seasons and gender. Total protein content (%) of C. antalyensis varied from 63.80% to 78.15% and total fat content from 4.57% to 21.29% in different seasons. The palmitic, stearic, palmitoleic, oleic, eicosapentaenoic and docosahexaenoic acids were the most abundant fatty acids in the muscles of C. antalyensis. The ratio of eicosapentaenoic acid (EPA) in muscles of both genders was higher in spring and autumn, while docosahexaenoic acid (DHA) ratio was higher in winter. The ratio of omega 3 polyunsaturated fatty acids (n3 PUFAs) content in the muscles reached the highest level in spring in males and in summer in females. The ratios of n-3 PUFAs to omega 6 polyunsaturated fatty acids (n6 PUFAs) in muscles of C. antalyensis of both genders changed from 3.29 to 5.44 as the seasons changed. Total fat and fatty acid contents were found to be at the lowest level in both genders during winter. This shows that nutritional content of C. antalyensis species is quite affected by variation in seasonal conditions.

The relationships between asteriscus otolith morphology (OL, OW, OR and OM) and fish total length were described with a non-linear function (power model) for seven Cyprinid fish species: Capoeta angorae, C. antalyensis, C. caelestis, C. erhani, C. pestai, Pseudophoxinus antalyae and P. fahrettini. These species are endemic to Turkey and have limited distributions. The regression models are quite well fitted with all asteriscus otolith measurements. We were also conducted the regression models for genus level. There was no significant difference between the size of the left and right otoliths (paired t-test) in any of the seven species. This is the first study that examines the relationships between asteriscus otolith morphology and fish total length for four Cyprinid species. These results showed that the equations generated to obtain the fish size using otolith morphology data can be used in dietary studies.