51 research outputs found
First record of the Guppy (Poecilia reticulata Peters, 1859) in inlandwaters of Turkey
No full textTURKMEN, GUREL/0000-0002-2683-6258The ever-increasing global trade of ornamental aquarium fishes is one of the most important pathways for aquatic invasion. Occurrence of ornamental freshwater fishes in natural freshwaters has been increasing in recent years. the ornamental trade accounts for a limited but steadily growing proportion of fish introductions to Turkish inlandwaters. in this study, Guppy, Poecilia reticulata, is recorded for the first time from natural inlandwaters of Turkey. P. reticulata was probably released into the wild, but is now established in aquifer of Cesme-Ildir (Izmir)
Experimental commercial growout of Penaeus semisu/catus (Decapoda: Penaeidae)
No full textSea bass and sea bream have become almost synonymous with marine aquaculture in Turkey, indicating the level of commercial success they have attained during the last two decades. However, to diversify an industry overly dependent on these two products, as well as to provide the market with an additional commodity, other species are being considered for future culture. In the present study, commercial culture of Penaeus semisulcatus on the Aegean coast of Turkey was evaluated. In 150 days, the shrimp grew from 0.03 g to 18.72 g, with a mean daily growth rate of 0.125 g. The food conversion rate and specific growth rate were 2.26 and 2.34, respectively. Production reached the equivalent of 2880 kg/ha with a survival of 77%. While pro- duction results and shrimp weights were considerable, to obtain larger shrimp of greater value, early maturation and spawning in a nursery system must be included in conjunction with the growout ponds
Seasonal Variation of Heavy Metals in Shrimp Penaeus kerathurus (Forskal, 1775) from Izmir Bay, Turkey
No full textSeasonal changes in heavy metals (Cd, Cu, Fe, Pb, Zn) concentrations in muscle tissues of both male and female caramote shrimp (Penaeus kerathurus) from Izmir bay, Turkey were measured for a year period by using flame and graphite furnace AAS. The relationships in various heavy metal concentrations were compared according to sex and seasons. Heavy metal content varied with type of metals, seasons and sex. The highest concentration of heavy metal in the muscle tissue of P. kerathurus for Cd, Pb, Cu, Fe and Zn was registered in Summer months. Mean Fe level in male shrimps was considerably higher (30.19 compared to 20.23 mu g g(-1) dry eight) in October. Regarding Cu, the same case could be observed (27.58 mu g g(-1) dry weight in males compared to 19.02 in females). In the present study, heavy metals accumulated in the shrimp muscle in the order Zn>Fe>Cu>Pb>Cd. Concentrations of metals ranged within the recommended limits for human consumption and not represent a health risk
The Survey of the Imported Freshwater Decapod Species via the Ornamental Aquarium Trade in Turkey
No full textIn this study, the situation with imported freshwater decapod species via the live aquarium ornamental trade in Turkey was investigated year round during 2011. The scientific and common names, native geographic regions, import sizes and prices were recorded. Among the 28 imported freshwater decapod species recorded in this survey, 15 are shrimps, 9 are crayfish and 4 are crabs. Those imported species might have escaped or have been released into the wild due to misguided cultural habits or incorrect conservation concepts. The objective of this study is to raise awareness of imported freshwater decapods and to present a list of the species currently traded in the aquarium industry in Turkey
Trypsin enzyme activity during larval development of Penaeus semisulcatus De Haan, 1844, fed on live feeds
No full textThe growth, survival, and trypsin activity response of Penaeus semisulcatus larvae was examined with two different live feed regimes throughout larval development under laboratory conditions. In the first feeding regime, larvae were fed standard live diets of mixed microalgae from the first to the third protozoea (PZ1 to PZ3), followed by Artemia nauplii until postlarva 1 (PL1). In the second feeding regime, larvae were fed a diet of Artemia nauplii at the beginning of the PZ2 stage. Like other penaeids, P. semisulcatus larvae showed high trypsin activity during the late protozoeal or early mysis stages, which decreased during subsequent stages when fed on conventional live diets of microalgae followed by Artemia nauplii during the mysis stages. P semisulcatus larvae fed Artemia nauplii from PZ2 onward were significantly heavier on reaching M1 than those fed microalgae (P < 0.05). In contrast, the survival rate of larvae fed with the first feeding regime was higher than that of those in the second feeding regime (P < 0.05). The trypsin activity level in stages PZ2, PZ3, M1, and M2 fed Artemia nauplii was significantly lower than that in the same stages fed microalgae (P < 0.05)
Developing authentic problems through lived experiences in nature
No full textThis study's main objective is to develop a theoretical and ontological basis for experimentation in contact with the real life, oriented to physics education. Physics is built upon the observation of nature, where our experience provides opportunity to deal with science in natural environment to those learners who have background in the very basics and essentials of physics. Physics in Nature course includes visiting and camping experiences situated in nature and organizing camp with educational purposes. The course has been integrated with indoor and outdoor settings interactively and the authentic problems, which have been taken from outdoor settings, have been brought into the class without well-defined structure (Ill-structured problems). Within the period of ten years, there were plethora of events and problems that would provide sufficient material for many researchers. Because every problem is an event and has a story. The philosophical event concept of Deleuze and Guattari has been used in the events of Physics in Nature courses. Post-qualitative research methodology has been used in order to put forward how to construct the relation between physics and nature and become the main problem in the physics in nature, thereby it has been the basis of the course and our academic researc
Some biological aspects of Melicertus kerathurus (Forskal, 1775) (Decapoda, Penaeidae) inhabiting Izmir Bay (Aegean Sea), Turkey
No full textSome biological aspects of Melicertus kerathurus, a shrimp of high commercial value, were studied in Izmir Bay from April 2004 to December 2004. A seasonal reproduction pattern was observed from April to September with a high percentage of mature females occur-ring between May and July, when water temperature was relatively high. During the study, a total of 1050 specimens was captured: 612 (58.3%) females and 438 (41.7%) males. The largest female and male were 22.7 cm and 17.0 cm, respectively. The minimum size attained at first maturity was estimated to be 3.9 cm carapace length (CL) and 14.1 cm total length (TL). Sexual differences related to the length-weight relationship were noted. The onset of sexual maturity for females was estimated to be CL50% = 4.6 cm and TL50% = 16.5 cm
Improved in vitro propagation and direct acclimatization of Cryptocoryne wendtii in aquarium in the presence of aquarium fish Puntius tetrazona (Bleeker)
No full textWOS: 000469889600004Cryptocoryne wendtii is an important ornamental aquatic plant and has difficulties in conventional cultivation. In the present study, we propose an efficient in vitro propagation and acclimatization protocols for C. wendtii. The highest number of shoots was achieved on Murashige and Skoog (MS) medium containing 4.0 mg/L BA+1.0 mg/L IBA. In the second subculture, the number of shoots per explant increased from 7.2 to 51.8 in this medium. The shoot length per explant, the percentage of shoots rooted, and the number of roots per shoot were maximum in MS medium supplemented with 1.0 mg/L IBA. The in vitro rootless and rooted shoots were acclimatized in aquariums containing different substrates [Calcite (Ca), River Sand (RS), Zeolite (Ze) and Shell Grit (SG)] and tetrazona fish Puntius tetrazona (Bleeker). One third of the water in the aquariums was replaced with fresh tap water every two weeks and the water analyses were carried out before replacement of aquarium water everytime. All shoots were successfully acclimatized for a period of 3 months. The RS and rooted shoot explants were found to be more effective than the other substrates, and rootless shoots in terms of all parameters that were tested
Effects of zinc supplementation on the immune system and on antibody response to multivalent influenza vaccine in hemodialysis patients
No full textThe depression of the immune system in chronic uremia is a well-known phenomenon but the role of serum zinc (Zn) levels on both cell-mediated and humoral immunity is still controversial. The aim of this study was to investigate the effect of Zn supplementation on the immune system and on antibody response to multivalent influenza vaccine (MIV) in hemodialysis patients (HP). Twenty-six HP and I I healthy subjects (HS) were vaccinated with MIV: Hemodialysis patients were randomly divided into two groups. Group 1 (13 HP) was supplemented with 120 mg ZnSO4 after each dialysis session. Group 11 (13 HP) and Grouip III (11 HS) were given placebo. In all cases, the serum Zn levels, CD3, CD4, CD8, CD19, HLA-DR+ cell percentages, CD4/CD8 ratio and CD3+HLA-DR+ cell percentages were determined before and 30 days after vaccination. Antibody levels to subgroups of MIV were also measured. All the baseline parameters studied were not statistically different between Group I and II. However, there was a significant difference between the basal parameters of Group III and the other two groups, except for CD3 and CD4 cell percentages. Serum Zn, CD19 cell percentage and antibody levels to MIV subgroups were significantly increased in Group I at the end of the first month of the study (p<0.01, p<0.05, p<0.001, p<0.001, and p<0.01, respectively), but the other parameters showed no significant changes. The only significant change observed in Groups II and III was an increase in antibody levels to MIV subgroups one month after vaccination. Antibody levels to MIV subgroups, were not statistically different between Groups I and II, but in Group III they were strikingly higher than those of HP (p<0.001). These results led us to conclude that Zn supplementation could not restore the immune parameters and enhance antibody response to MIV in HP
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