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    A COMPARATIVE ANALYSIS OF WATER QUALITY ASSESSMENT METHODS FOR HEAVY METAL POLLUTION IN KARASU STREAM, TURKEY
    (Parlar Scientific Publications (P S P), 2013) Sonmez, Adem Yavuz; Hisar, Olcay; Yanik, Telat
    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 Karasu 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 Ill 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.
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    A comparative analysis of water quality assessment methods for heavy metal pollution in karasu stream, Turkey
    (2013) Sönmez, Adem Yavuz; Hisar, Olcay; Yanik, Telat
    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 Karas? 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.
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    An assessment of the effects of climate change on annual streamflow in rivers in Western Turkey
    (Inderscience Enterprises Ltd, 2018) Kale, Semih; Hisar, Olcay; Sonmez, Adem Yavuz; Mutlu, Fatih; Filho, Walter Leal
    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 Buyuk 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.
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    Body amino acid composition of axillary seabream (Pagellus acarne R., 1827) catched from dardanelles (Canakkale, Turkey)
    (CEUR-WS, 2015) Öztekin, Alkan; Kizilkaya, Bayram; Aslan, Alparslan; Selvi, Kahraman; Yılmaz, Sevdan; Hisar, Olcay; Ergün, Sebahattin
    Amino acid composition of the whole body tissue of Axillary seabream (Pagellus acarne) was determined. Fish was catched from Dardanelles (April 2013) via fishing line. The most abundant amino acid was Glutamic Acid (11.0 g/100 g crude protein) and Valine was the most abundant essential amino acid (6.2 g/100 g crude protein). The total essential amino acid content was 32.3 g/100 g crude protein and the total nonessential amino acid content was 42.5 g/100 g crude protein. Copyright © 2015 for this paper by authors.
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    Changes in liver and kidney antioxidant enzyme activities in the rainbow trout (Oncorhynchusmykiss) exposed cadmium
    (Chemical Publishing Co., 2009) Hisar, Olcay; Yildirim, Sükrü; Sönmez, Adem Yavuz; Aras, Hatice Nur; Gultepe, Nejdet
    In vivo effects of cadmium on antioxidant enzymes such as super- oxide dismutase (SOD), catalase (CAT), glutathione Peroxidase (GPx) and glutathione reductase (GSR) investigated in liver and kidney tissues of rainbow trout (Oncorhynchus mykiss). Three test groups of fish were subjected to cadmium in concentrations of 0 (control), 1 and 5 ppm. The duration of exposure was 1,3,5 and 7 d. The antioxidant enzyme activities, measured liver and kidney homogenates, were stimulated by both concentration (1 and 5 ppm) of cadmium chloride. Moreover, the dose-response patterns of the antioxidant enzyme activities in the liver and kidney tissue were very similar. All antioxidant enzyme activities were significantly stimulated on the first day of experiment (Day 1) in the tissues at the both dose of Cd (p < 0.05) while CAT activity was stimulated after 3 days in the tissues at a dose of 1 ppm Cd (p < 0.05). The stimulation effect of Cd on SOD, GPx and GSR activities in the tissues diminished after 7 d cadmium administration. However, this effect of Cd on CAT activity diminished after 5 d. These findings indicate that the tissue antioxidant enzymes function to protect against cadmium toxicity.
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    Effect of Climate Change on Annual Streamflow of Bakırçay River
    (2016) Mutlu, Fatih; Hisar, Olcay; Ejder, Tuba; Kale, Semih
    Küresel ısınma ve bundan kaynaklanan iklim değişikliği doğal kaynakların sürdürülebilirliği açısından önemli sorunlara neden olmaktadır. Bu çalışmada Türkiye'nin batısında yer alan Ege Denizi kıyısındaki 9 meteoroloji gözlem istasyonuna ait 43 yıllık sıcaklık, yağış, buharlaşma gibi meteorolojik parametreler ile aynı bölgede yer alan ve Ege Denizine dökülen Bakırçay nehrine ait 17 yıllık veri seti kullanılmıştır. İklim parametreleri ile nehir akış hızına ait değişim noktalarının belirlenmesi için Pettitt değişim noktası analizi, eğilimlerin belirlendiği trend analizleri için Box-Jenkins yöntemi ve ARIMA modeli, bu parametreler arasındaki ilişkileri belirlemek için ise Kendall's Tau ve Spearman's rho korelasyon testleri kullanılmıştır. Pettitt testi sonucu sıcaklık, buharlaşma ve yağış miktarları için değişim yılları sırasıyla 1997, 1993 ve 1993 iken Bakırçay nehrinin akış hızı için ise 2008 olarak belirlenmiştir. Gerçekleştirilen trend analizleri sonucunda sıcaklık ve buharlaşma miktarında artış; yağış miktarı ve nehir akış hızında ise azalış olduğu tespit edilmiştir. Ancak bu parametrelerin yıllara göre değişimi ile iklim parametreleri ve nehir akış hızı arasındaki korelasyonların istatistiksel olarak önemsiz olduğu belirlenmiştir (p>0.05). Sonuç olarak iklim değişikliğinin nehir akış hızları üzerine olan etkilerinin değişken olabileceği, küresel ısınmanın nehir sistemleri üzerine etkilerinin belirlenmesinde antropojenik etkiler, coğrafi konum, tarımsal faaliyetler, yerleşim yerleri ve nüfus yoğunluğu gibi birçok faktörün de dikkate alınması gerektiği düşünülmektedir. Ayrıca iklim değişikliğinin nehirlerin hidrolojik süreçleri üzerine olan etkilerinin değerlendirilmesinde bölgeye ve amaca uygun değerlendirme modellerinin kullanılması ve özelleştirilmiş yönetim stratejilerinin geliştirilmesi önerilmektedir
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    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
    (Central Fisheries Research Inst, 2015) Sonmez, Adem Yavuz; Bilen, Soner; Albayrak, Mevlut; Yılmaz, Sevdan; Biswas, Gouranga; Hisar, Olcay; Yanik, Talat
    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.
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    Effects of environmental hypercapnia on hemato-immunological parameters, carbonic anhydrase, and Na+, K+-ATPase enzyme activities in rainbow trout Oncorhynchus mykiss) tissues
    (Taylor & Francis Ltd, 2013) Kaya, Hasan; Yılmaz, Sevdan; Gurkan, Mert; Hisar, Olcay
    In this study, the effects of environmental hypercapnia on hemato-immunological parameters and the activities of respiratory enzymes such as carbonic anhydrase (CA) and Na+, K+-ATPase were investigated in rainbow trout (Oncorhynchus mykiss) tissues (gill, liver and kidney). Batches of 12 fish were exposed to 4.5mg L-1 (control) and 14mg L-1 CO2. No mortalities occurred during the 14days of the experimental period. Red blood cell (RBC), hemoglobin (Hb), and hematocrit (Ht) levels, and innate immune parameters such as nitro blue tetrazolium (NBT), lysozyme, and myeloperoxidase activities, and the melano-macrophage frequency were negatively affected by elevated CO2 levels. Patterns of change in CA activity differed among the gill, liver, and kidney. Compared with the activities of CA in the control group, the CA enzyme was significantly stimulated at day 7 in the gill tissue, whereas it was stimulated at day 14 of the experiment in the liver tissue of fish exposed to 14mg L-1 CO2 (P < 0.05). In contrast to the pattern of CA enzyme activities, the Na+, K+-ATPase enzymes were stimulated significantly in the liver after day 7 but inhibited in the kidney and gill (P < 0.05). These results suggest that a subchronic exposure to hypercapnia of rainbow trout tissues may lead to adaptive changes in the respiratory enzymes and negatively affects hemato-immunological parameters.
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    Effectsof Dietary Supplementation of Herbal OilsContaining1,8-cineole, Carvacrol or Pulegone on Growth Performance, Survival, Fatty Acid Composition, andLiver and Kidney Histology of Rainbow Trout (Oncorhynchus mykiss) Fingerlings
    (2015) Sönmez, Adem Yavuz; Bilen, Soner; Albayrak, Mevlüt; Yılmaz, Sevdan; Bıswas, Gouranga; Hisar, Olcay; Yanık, Talat
    Sırasıyla 74 g kg-1 pulegon, 77 g kg-1 karvakrol ve 76 g kg-1 1,8-kinol içeren nane, kekik ve adaçayı gibi üç farklı bitkisel yağın alabalıkların (Oncorhynchus mykiss) büyüme performansı, yaşama, yağ asidi kompozisyonu ile karaciğer ve böbrek histolojisi üzerine etkilerini belirlemek amacı ile bu besleme çalışması yürütülmüştür. Bitkisel yağlar balık yemi içerisine % 0,5, % 1 ve % 1,5 oranında eklenmiş, ve her diyet büyüme parametreleri haftalık olarak kontrol edilen 60 günlük çalışmada üç tekerrürlü olarak alabalık yavrularına verilmiştir. FCR tüm nane gruplarında olumsuz etkilenirken diğer tüm gruplardan yüksek tespit edilmiştir (P<0,05). En düşük FCR oranları kekik ve adaçayı içeren gruplarda belirlenmiştir (P<0,05) ve bu gruplar arasında farklılık tespit edilememiştir. SGR nane grubunda kontrol grubunda olduğundan daha düşük çıkmıştır. En yüksek SGR değerleri kekik be adaçayı içeren gruplarla beslenen alabalıklarda gözlenmiştir (P<0,05). Yaşama gücü, kekik, adaçayı ve kontrol grubunda benzer olmuştur (P>0,05). Bununla birlikte nane yağı ile beslenen gruplarda düşük tespit edilmiştir (P<0,05). Toplam doymuş yağ asidi hariç tüm yağ asitleri içeriği bitkisel yağ eklentisi ile değişiklik göstermiştir. Toplam çoklu doymamış n-6 yağ asitleri % 1 kekik ve tüm adaçayı içeren gruplarda en düşük değeri göstermiştir (P<0,05). Toplam çoklu doymamış n-3 yağ asitleri kontrol ve adaçayı yağı ekleniş gruplarda benzerken, diğer gruplarda önemli derecede düşmüştür (P<0,05). EPA/DHA oranı % 1,5 kekik yağı ve tüm adaçayı yağı içeren gruplarda kayda değer düşüktür. Kontrol, % 0,5 ve % 1 kekik ve adaçayı yağı içeren gruplarda karaciğer ya da böbrek histolojilerinde bir farklılık gözlenmemiştir. Bu çalışma sonuçları kekik ve adaçayı ile desteklenmiş yemlerin büyüme performansı ve yağ asidi kullanımı üzerindeki olumlu etki gösterdiğini ortaya koymuştur ve bu yağlar alabalık üretiminde yem katkısı olarak kullanışlı olabileceği belirlenmiştir
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    Fuzzy Logic Evaluation of Water Quality Classification for Heavy Metal Pollution in Karasu Stream, Turkey
    (Foundation Environmental Protection & Research-Fepr, 2013) Sonmez, Adem Yavuz; Hasiloglu, Samet; Hisar, Olcay; Aras Mehan, Hatice Nur; Kaya, Hasan
    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.
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    Growth performance and antioxidant enzyme activities in rainbow trout (Oncorhynchus mykiss) juveniles fed diets supplemented with sage, mint and thyme oils
    (Springer, 2015) Sonmez, Adem Yavuz; Bilen, Soner; Alak, Gonca; Hisar, Olcay; Yanik, Talat; Biswas, Gouranga
    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.
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    Karasu Irmağında ağır metal kirliliğinin tespiti ve su kalitesinie göre sınıflandırılması
    (2012) Sönmez, Adem Yavuz; Hisar, Olcay; Yanık, Telat
    Karasu Irmağından seçilen 5 istasyondan 12 ay boyunca alınan su örnekleri Bakır (Cu), Çinko (Zn), Mangan (Mn), Kurşun (Pb), Nikel (Ni), Kadmiyum (Cd) ve Demir (Fe) bakımından incelenmiştir. Elde edilen ağır metal verilerine göre istasyonlar arasmda tüm ağır metallerin değişimlerinde önemli derecede farklılıklar gözlemlenmiştir (p<0.01). Aylara göre ağır metallerin değişimleri incelendiğinde örnekleme noktalarından elde edilen verilerin istatistiki olarak önemli ölçüde değişmediği tespit edilmiştir (p>0.05). Ancak, aylar x istasyonlar interaksiyonu istatistikî bakımdan çok önemli (p<0.01) bulunmuştur. Irmağın önemli ölçüde kirliliğe maruz kaldığı tespit edilmiştir.
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    Karasu Nehri (Türkiye) ağır metal kirliliği için su kalite sınıflandırılmasının bulanık mantık ile değerlendirilmesi
    (2013) Sönmez, Adem Yavuz; Hasıloglu, Samet; Hisar, Olcay; Mehan, Hatice Nur Aras; Kaya, Hasan
    Geleneksel su kalite değerlendirme metotlarında; alt ve üst limitleri içeren ayırım tabloları kullanılmaktadır. Gözlenen konsantrasyon değerleri, ayırım tablolarında aynı bölge içerisinde yer alıyorsa; değerler limitlere yakın yada uzak olsun aynı eşit öneme sahiptir. Ayrıca her bir kalite parametresi, tabloda yer alan dört sınıftan birisi içerisinde yer almalıdır. Bu nedenle, her bir parametrenin farklı sınıflarda olduğu durumlarda da belirsizlik meydana gelir. Bu çalışmada, su kalite sınıflandırılmasının bulanık mantık ile değerlendirilmesinin yapıldığı bir indeks model kullanılmıştır. Bu amaç doğrultusunda; Karasu Nehrinde 5 istasyonda, 12 ay boyunca, toplam 180 adet ölçümü yapılarak; Bakır (Cu), Çinko (Zn), Manganez (Mn), Kurşun (Pb), Nikel (Ni), Kadmiyum (Cd) ve Demir (Fe) gibi bazı ağır metal konsantrasyonlarının veri kümesi oluşturulmuştur. Ardından Karasu Nehrindeki ağır metal kirliliği için bulanık mantık değerlendirme metodu kullanılmıştır. Sonuçta; çevre yönetiminde karar oluşturmak için bulanık mantık değerlendirme metodunun alternatif bir araç olabileceği düşünülmüştür.
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    Melatonin Implantation in Preovulatory Rainbow Trout (Oncorhynchus mykiss) under Short Photoperiod Regime Reduces Egg Quality
    (Central Fisheries Research Inst, 2014) Sonmez, Adem Yavuz; Aydin, Ilhan; Hisar, Olcay; Kaya, Hasan; Hisar, Sukriye Aras
    As in other vertebrates, the pineal organ in salmonids receives photic information directly through specialized photoreceptor cells to synchronize both daily and seasonal behavioral and physiological events, including the reproductive. In this study, the effect of a melatonin implantation before the preovulatory period on egg quality was investigated in rainbow trout (Oncorhynchus mykiss) adults. Fish were exposed to two different lighting regimes [(constant short photoperiod (SP) of 6h light/18h dark) or natural photoperiod (NP) of 9h light/15h dark) with sub groups receiving a slow-release melatonin implant ((containing 9 mg melatonin hormone (MLT)) or sham implant. Melatonin implanted fish showed supraphysiological plasma MLT concentration during the 45 days after implantation. The spawning period started at the same time in all groups after implantation, although eggs were obtained from females exposed to SP lighting regimes only or SP lighting regimes plus implanted MLT exhibited significantly lower quality characterized by lower hatching rate and survival to first feeding than that of females expose to NP. In conclusion, it was determined that implantation of MLT in preovulatory rainbow trout females causes a decrease in egg quality. However, future investigations should be conducted to ascertain the MLT dose required for and time of implantation in rainbow trout.
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    Metals in Two Species of Fish in Karasu River
    (Springer, 2012) Sonmez, Adem Yavuz; Yaganoglu, A. Mutlu; Arslan, Gokhan; Hisar, Olcay
    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.
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    Preliminary Assessment of Dietary Mannanoligosaccharides on Growth Performance and Health Status of Gilthead Seabream Sparus auratus
    (Taylor & Francis Inc, 2012) Gultepe, Nejdet; Hisar, Olcay; Salnur, Semih; Hossu, Belgin; Tanrikul, T. Tansel; Aydin, Seyit
    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 degrees C to 24.7 degrees 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. The mean Thr count ranged from 47.6 to 53.8 x 10(3)/mm(3). 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 with MOS had no significant effects on general fish health.
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    Sustainability of Effective Use of Water Sources in Turkey
    (Springer Verlag, 2015) Hisar, Olcay; Kale, Semih; Özen, Özcan
    Water is the most essential natural resource for sustainable development of human society as well as the most vital source for viability of human and natural systems. However, natural water resources had been threaten by increase of temperature due to global warming and improper usage, causing health problems both for human and aquatic environment. On the other hand, global water consumption has increased because of growth in population and increase of the per capita water use. To make adjustments to the water utilization, the need is allocating limited water resources and increasing local water use efficiency. Sustainability is a relative concept that must be applied in an environment undergoing multiple changes that are occurring over different temporal and spatial scales. Contrary to the popular belief, Turkey is not a water-rich country. Turkey depends on its water resource systems for survival and welfare. Therefore, new studies have been forced in the rehabilitation and sustainable usage of water sources recently in the world. In this paper, information about their current state and future projections is given based on many published data. © 2015, Springer International Publishing Switzerland.
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    The effects of elevated carbon dioxide and temperature levels on tilapia (Oreochromis mossambicus): Respiratory enzymes, blood pH and hematological parameters
    (Elsevier Science Bv, 2016) Kaya, Hasan; Hisar, Olcay; Yılmaz, Sevdan; Gurkan, Mert; Hisar, Sukriye Aras
    Oreochromis mossambicus were exposed to two different temperature and carbon dioxide partial pressure levels for about two weeks, as the ambient (Control; 25 degrees C, 3.3 mg/L CO2), high CO2 (25 degrees C, 14 mg/L CO2), high temperature (30 degrees C, 3 mg/L CO2) and combined (30 degrees C, 14.1 mg/L CO2) groups. No mortality was observed during the experiments. As a result of the study, elevated CO2 concentrations cause negative effects on the hematological parameters. At the end of the study, while the blood Carbonic Anhydrase (CA) activity, in the high CO2 group (25 degrees C, 14 mg/L CO2), statistically increased at the 7th day compared to the control group, it decreased at the 14th day (p<0.05). In addition, the blood CA activity, in the combined (30 degrees C, 14.1 mg/L CO2) group, showed a decrease at the 14th day compared to the control group (p<0.05). At the end of study, unlike the blood CA activity, gill, liver and kidney CA activity showed an increase in the tissues compared to the control groups (p<0.05). Furthermore, the Na+, K+-ATPase activities were stimulated significantly in the gills in both high CO2 and temperature groups at day 7, but it showed a significant amount of inhibition at the 14th day compared to the control groups. Overall, increasing carbon dioxide concentration in different temperatures has negative effects on the hematological parameters and respiratory enzyme of the tilapia fish. In addition, it is observed that the fish survive at negative conditions with adaptation mechanisms. (C) 2016 Elsevier B.V. All rights reserved.