Browsing by Author "Hisar O."

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A comparative analysis of water quality assessment methods for heavy metal pollution in karasu stream, Turkey
(2013-04-05) Sönmez A.; Hisar O.; Yanik T.
Heavy metals are among the most persistent of pollutants in aquatic systems due to their resistance to decomposition in nature. Four assessment methods (two pollution indexes and two fuzzy mathematical models - single-factor deciding and weighted average models) were used to check the level and characteristics of heavy metal pollution in the Karasů stream water. Several heavy metals such as Copper (Cu), Zinc (Zn), Manganese (Mn), Lead (Pb), Nickel (Ni), Cadmium (Cd) and Iron (Fe) were tested with these methods. A data set (12 months, total 180 measurements) was collected from 5 sampling points (A-E) of the River. The used criteria were classes, I-IV represents from clear to polluted one. Water quality was assessed as class IV from all water samples collected from the each station with single-factor index method. It was identified to be class IV from the samples of A, B, C and D stations, and class III from the sample of E station with the comprehensive index model. By using the fuzzy mathematical methods, the water quality were determined as classes of IV, IV, IV, II and II from the water samples of A, B, C, D and E stations respectively. Introduction of membership degree and weight of each factor to fuzzy mathematical models made the methods more reasonable in the field of water quality assessment. Therefore, these fuzzy mathematical methods might be quite convenient in evaluation of water pollution and classification considering the results of the present study. © by PSP.
An assessment of the effects of climate change on annual streamflow in rivers in Western Turkey
(2018-01-01) Kale S.; Hisar O.; Sönmez A.Y.; Mutlu F.; Filho W.L.
Global warming and its impacts are known to cause serious problems in sustainability of natural resources. In this study, change-point analysis and trend analysis were applied to climatic (temperature, precipitation, evaporation) and streamflow data for Tuzla, Gediz and Büyük Menderes rivers. Box-Jenkins technique and ARIMA model were used for trend analysis. Results showed that there were decreases in streamflow of all rivers. The paper suggests that climate change effects on streamflow could be changeable and that many factors (anthropogenic effects, geographical location, agricultural activities) should be considered. Management strategies specified regionally are required to mitigate the potential climate change effects.
Carbonic anhydrase activities from the rainbow trout lens correspond to the development of acute gas bubble disease
(2011-09-26) Gültepe N.; Ateş O.; Hisar O.; Beydemir S.
Dissolved gas supersaturation is hazardous to fish and can result in gas bubble disease (GBD). Signs of GBD typically include bubbles in the eyes, fins, skin, lateral line, and gill filaments. Ocular abnormalities in diseased salmonids typically occur after aberrant gas production in the eyes. In this study, freshwater rainbow trout Oncorhynchus mykiss were exposed experimentally to percent total gas pressure (TGP%) levels of 104% (control) and 115%. No mortalities occurred during the 7-d experimental period. Effects of GBD were observed externally as a darkened skin, exophthalmia, localized hemorrhage in the eye, and gas bubbles on the operculum. Additional signs included increased swimming activity and, more frequently, panic episodes. Carbonic anhydrase (CA) enzyme activities from the lens and retina were determined at days 0, 1, 3, 5, and 7 of the study. Venous blood gases were alsomeasured on day 7. Retinal pH did not differ between normal and affected fish, but blood characteristics such as the partial pressure of O 2, partial pressure of CO 2, carboxyhemoglobin level, and bicarbonate ion concentration were significantly elevated in affected fish relative to normal fish. Venous blood pH and oxyhemoglobin levels were not significantly different between affected and normal fish. Patterns of response to total dissolved gas levels differed between the lens and the retina. Mean CA activities in the lenses of fish exposed to a TGP% level of 115% were significantly below those of control fish. However, retinal CA activities did not significantly differ between the two groups over the course of the experiment. These findings show that dissolved gas supersaturation reduces CA activity in the rainbow trout lens. © American Fisheries Society 2011.
Effects of dietary supplementation of herbal oils containing 1,8-cineole, carvacrol or pulegone on growth performance, survival, fatty acid composition, and liver and kidney histology of rainbow trout (Oncorhynchus mykiss) fingerlings
(2015-01-01) Sönmez A.; Bilen S.; Albayrak M.; Yılmaz S.; Biswas G.; Hisar O.; Yanık T.
A feeding trial was performed to assess any beneficial effect of three herbal oils; mint, thyme and sage oils containing 74 g kg-1 pulegone, 77 g kg-1 carvacrol and 76 g kg-11,8-cineole, respectively on growth performance, survival, fatty acid composition, and liver and kidney histology of rainbow trout (Oncorhynchus mykiss). Herbal oils were added at 0.5 %, 1.0% and 1.5 % concentrations to a fish meal-based control diet, and each diet was fed to triplicate groups of rainbow trout fingerlings for 60 days with growth parameters recorded weekly. Results showed that FCR was affected negatively in all mint oil diet fed groups where it was higher than that of control and other groups (P<0.05). The lowest FCR values were recorded in the thyme and sage oil containing diets fed groups (P<0.05) with no significant differences between these two groups. SGR was also found lower in mint oil groups than in control. The highest SGR was recorded in thyme and sage oil fed groups (P<0.05). Survival was similar in fish fed with diets containing thyme, sage oil and control diet (P>0.05). However, survival was the lowest in fish fed with mint oil supplemented diets(P<0.05). Whole body fatty acid profiles except total saturated fatty acids are closely influenced by dietary herbal oil administrations. Total polyunsaturated n-6 fatty acid was lowest in 1 %thyme oil and all sage oil diet fed groups (P<0.05). Total polyunsaturated n-3 fatty acid was similar between control and sage oil supplemented groups, but in other groups it was significantly decreased (P<0.05). EPA/DHA ratio was observed significantly low in 1.5 %thyme oil and all groups of sage oil fed fish. There were no histological differences observed in liver or kidney of fish fedwith control and 0.5 % and 1 % thyme and sage oil supplemented diets.The present results showed positive effects of thyme and sage herbal essential oil supplemented diets on growth performance and fatty acid utilization and these oils may be useful feed supplements in production of rainbow trout.
Fuzzy logic evaluation of water quality classification for heavy metal pollution in karasu stream, Turkey
(2013-01-01) Sonmez A.Y.; Hasiloglu S.; Hisar O.; Aras Mehan H.N.; Kaya H.
Traditional water quality evaluation methods use discrete form that involve upper and lower limits, and the concentrations values are equally important when the values are near to or far away from the limits. Moreover, each quality parameter might belong to one of the four classes; therefore differences of the classes of the parameters may be vagueness. In this study, an index model is purposed for quality evaluation of water quality classification using fuzzy logic. For that purpose, a data set (12 months, total 180 measurements) about several heavy metals such as Copper (Cu), Zinc (Zn), Manganese (Mn), Lead (Pb), Nickel (Ni), Cadmium (Cd) and Iron (Fe) was collected from 5 monitoring stations in Karasu River. After that, fuzzy logic assessment method was used to quality evaluation for heavy metal pollution in Karasu stream. In conclusion, it was supposed that fuzzy logic evaluation method may also be used as an alternative tool for decision-making in environmental management.
Growth performance and antioxidant enzyme activities in rainbow trout (Oncorhynchus mykiss) juveniles fed diets supplemented with sage, mint and thyme oils
(2015-02-01) Sönmez A.Y.; Bilen S.; Alak G.; Hisar O.; Yanık T.; Biswas G.
This study evaluated effects of dietary supplementation of sage (Salvia officinalis), mint (Mentha spicata) and thyme (Thymus vulgaris) oils on growth performance, lipid peroxidation level (melondialdehyde, MDA) and liver antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; glucose-6-phosphate dehydrogenase, G6PD; glutathione reductase, GR; glutathione-S-transferase, GST and glutathione peroxidase, GPx) in rainbow trout (Oncorhynchus mykiss) juveniles. For this purpose, triplicate groups of rainbow trout were fed daily ad libitum with diets containing sage, mint and thyme oils at 500, 1,000 and 1,500 mg kg−1 for 60 days. While weight gain percentage of fish fed the diets containing sage and thyme oils was significantly higher than the control group, that of fish fed mint oil was the lowest. Similarly, specific growth rate was found to be the highest in all groups of the sage and thyme oil feeding and the lowest in the mint groups. Moreover, feed conversion ratio was significantly higher in the mint oil administered groups. Survival rate was also significantly reduced in the fish fed the diet containing mint oil. It was observed that SOD, G6PD and GPx activities were significantly increased in liver tissues of all the treated fish groups compared to that of control diet-fed group. However, CAT, GST and GR activities were significantly decreased in experimental diet-fed fish groups at the end of the experiment. On the other hand, a significant reduction was found in MDA levels in the fish fed the diets with sage and thyme oils compared to control and mint diets on the 30th and 60th days of experiment. Overall, dietary inclusion of sage and thyme oils is effective in enhancing rainbow trout growth, reduction in MDA and least changing antioxidant enzyme activities at a low level of 500 mg kg−1 diet, and they can be used as important feed supplements for rainbow trout production.
Metals in two species of fish in Karasu River
(2012-12-01) Sönmez A.Y.; Yaganoglu A.M.; Arslan G.; Hisar O.
In this study, cadmium (Cd), copper (Cu), iron (Fe), nickel (Ni), lead (Pb) and zinc (Zn) levels were determined in the tissues (muscle, liver and gills) of two fish species, Capoeta capoeta umbla and Chalcalburnus mosullensis, collected from three stations of the Karasu River. The lowest metal accumulation was detected in the muscle tissues. Moreover there was some variability in the metal concentrations measured in the same tissues from samples obtained from the three different stations. A positive correlation was observed for the concentration of metal pairs Fe-Cu, Fe-Zn, Ni-Pb, Pb-Zn. These findings were also compared with national and international food standards, and Pb and Cd concentrations were determined to be above the level set by the standards. In conclusion, it was supposed that excessive consumption of these two fish species, which already occurs in this region, might pose a public health risk. © Springer Science+Business Media New York 2012.
Preliminary assessment of dietary mannanoligosaccharides on growth performance and health status of gilthead seabream Sparus auratus
(2012-09-13) Gültepe N.; Hisar O.; Salnur S.; Hoşsu B.; Tansel Tanrikul T.; Aydin S.
A feeding trial was performed to assess the potential beneficial effect of two levels of mannanoligosaccarides (MOS) on the growth performance, feed utilization, hematological parameters, and liver histopathology of gilthead seabream Sparus auratus (also known as gilthead bream). Mannanoligosaccarides were added at the rates of 2 and 4 g/kg to a fish-meal-based control diet, and each diet was given (twice daily [midmorning and midafternoon] to apparent satiation) to triplicate groups of gilthead seabream growers (mean weight = approximately 170 g) in sea cages. The trial lasted 12 weeks, and the average ambient water temperature ranged from 19.6°C to 24.7°C during the experimental period. At the end of the experiment, fish attained market size (350-450 g) and their health status was evaluated by blood analysis and liver histology. There were no differences in survival rates among fish fed experimental diets. However, there were significant improvements in both growth and feed utilization among fish fed diets supplemented with MOS. Hemoglobin (Hb) and hematocrit (Ht) levels and erythrocyte, leukocyte, and thrombocyte (Thr) counts were unaffected by any dietary MOS. The levels of Hb (g/dL; mean ± SD) and Ht (%; mean ± SD) were 11.0 ± 2.5 and 45.6 ± 6.7 for the control group, 11.1 ± 1.7 and 39.3 ± 8.0 for the 2-g/kg group, and 11.2 ± 1.9 and 40.2 ± 8.4 for the 4-g/kg group. Themean Thr count ranged from 47.6 to 53.8 × 103/mm3. Despite the apparently higher Thr counts for fish fed diets supplemented with MOS, these differences were not significant. Moreover, no histopathological differences were observed in liver tissue cross sections between control and treatment groups. These results suggest that supplementation of diets withMOS had no significant effects on general fish health. © American Fisheries Society 2011.
The sexually dimorphic adipose fin is an androgen target tissue in the brown trout (Salmo trutta fario)
(2013-04-01) Hisar O.; Sönmez A.Y.; Hisar S.A.; Budak H.; Gültepe N.
An investigation has been described on the relationship of body length, age and sex with adipose fin length and the number of androgen receptor (AR)-containing cells in the adipose fin as a secondary sexual characteristic for brown trout (Salmo trutta fario). Firstly, body and adipose fin lengths of 2- to 5-year-old brown trout were measured. Thereafter, these fish were killed by decapitation, then their sexes were determined, and adipose fins were excised. The cellular bases of AR binding activities in the adipose fins were analyzed with an antibody against human/rat AR peptide. Immunocytochemistry and western blotting techniques were performed with this antibody. Analysis of morphological measurements indicated that body length and age had a linear relationship with adipose fin length. The coefficients of determination for the body length and age were 0. 92 and 0. 85 in the male fish and 0. 76 and 0. 73 in the female fish against the adipose fin length, respectively. At 2 years of age, cells in the adipose fin did not exhibit AR immunoreactivity. However, AR-immunopositive cells were abundant in the adipose fin of 3- to 5-year-old fish. Moreover, the number of AR-immunopositive cells was significantly (P < 0. 05) high in males and increased with age. These observations indicate that the adipose fin in the brown trout is a probable target for androgen action and that tissue function or development may to some extent be androgen dependent. In addition, it is likely that such an effect will be mediated by specific androgen receptors. © 2012 Springer Science+Business Media B.V.