Şerife Gülsün Kirankaya

Natural thermal adaptation increases heat shock protein levels and decreases oxidative stress

Heat shock proteins (HSPs), originally identified as heat-inducible gene products, are a family of highly conserved proteins that respond to a wide variety of stress including oxidative stress. Although both acute and chronic oxidative stress have been well demonstrated to induce HSP responses, little evidence is available whether increased HSP levels provide enhanced protection against oxidative stress under elevated yet sublethal temperatures. We studied relationships between oxidative stress and HSPs in a physiological model by using Garra rufa (doctor fish), a fish species naturally acclimatized to different thermal conditions. We compared fish naturally living in a hot spring with relatively high water temperature (34.4±0.6 °C) to those living in normal river water temperature (25.4±4.7 °C), and found that levels of all the studied HSPs (HSP70, HSP60, HSP90, HSC70 and GRP75) were higher in fish living in elevated water temperature compared with normal river water temperature. In contrast, indicators of oxidative stress, including protein carbonyls and lipid hydroperoxides, were decreased in fish living in the elevated temperature, indicating that HSP levels are inversely associated with oxidative stress. The present results provide evidence that physiologically increased HSP levels provide protection against oxidative stress and enhance cytoprotection.

Frequency of black spot disease in Cobitis cf. turcica from Pınarbaşı Springs (Haymana, Turkey)

Abstract. During a survey on the biology of Cobitis cf. turcica living in Pınarbaşı Springs (Haymana district, Turkey), symptoms of black spot disease were frequently observed on the specimens. Of the 1295 loach collected, 240 (19 %) specimens were found to be infected with metacercaria of Posthodiplostomum cuticola, a common digenean parasite causing black spot disease in freshwater fish in Eurasia. During spring and autumn, the infection rate was significantly higher than during winter and summer, most probably due to the increasing density of migration of birds in this area. No statistically significant difference was found in condition, weight and length between infected and non-infected specimens; indicating low physiological effects of the encysted metacercaria on the host specimens. However, the prevalence of black spot had a tendency to decrease with age, remarking a higher mortality rate of infected specimens. This increased mortality rate seems to be the most important impact of an infection with metacercaria for a Cobitis population.

Comparison of growth and reproduction of mirror carp and scaled carp introduced into Gelingüllü Reservoir, Yozgat, Turkey.

* Correspondence: gkirankaya@gmail.com

Feeding ecology of the Kızılırmak toothcarp, Aphanius marassantensis : ontogenetic shift and seasonal diet variation

We studied the feeding ecology of an endemic cyprinodontid fish, Aphanius marassantensis (Kızılırmak Toothcarp), with special emphasis on seasonal and ontogenetic diet shift. The dietary composition revealed an omnivorous diet with great seasonal and ontogenetic variation. Cladocera and Calanoid Copepods (Diaptomus sp.) dominated the diet in Spring and Summer, whereas the food items of plant origin e.g. filamentous algae and diatoms were the most important components in Autumn and Winter. An ontogenetic diet shift was also demonstrated. While the feeding of juveniles was based mostly on planktonic organisms, adult individuals preferred larger prey taxa, such as Gammarus sp. and Gastropods. There was no significant sex-related variation in feeding with the exception for the volume of gut content. The investigation on the feeding strategy of A. marassantensis suggested a generalised feeding pattern with some specialised individuals. This generalist feeding habits may account for the well-established population of this species in a big reservoir under coexistence of two non-native fish species, Pseudorasbora parva and Atherina boyeri.

Threatened Fishes of the World, Cobitis puncticulata (Erk’akan, Atalay-Ekmekçi & Nalbant, 1998) (Cobitidae)

Keywords Cobitis puncticulata.Brownspinedloach.Distribution.WesternAnatoliaCommon name: Brown spined loach (English) Kah-verengi copcu baligi (Turkish). Conservation status:Critically Endangered (IUCN 2009). Identification:Brownish body, consisting only of small dark-greydots through the body and head and blotches of Z2and Z4 (Gambetta 1934) are very small, indistinct orconfluent (Kottelat and Freyhof 2007). A strong keelis present above and below the caudal peduncle.Sexually dimorphic; males have one lamina circularisor scale of Canaestrini in the second pectoral fin ray(Erkakan et al. 1998). Females up to78 mm SL, malesare smaller. Distribution: Apart from the Kocacay andthe Karadere from the Manyas (Kus) Lake drainage(Erk’akan and Ekmekci 2000), recorded from theRiver Evros in Greece (Thrace) and in the UluabatLake catchment in the east of Manyas Lake (Freyhofet al. 2008). In 2005, we found this species inBakacak Stream a tributary of the Kocabas drainage(Marmara Sea) in Canakkale (Ekmekci et al. 2008).Abundance: Recorded as rare by IUCN (Crivelli 2006).Habitat and ecology: Still to moderate flowingstreams, with muddy or sand substrate. Reproduction:No data, only known to spawn in spring. Threats:InTurkey, pollution and flow regulation are the mostimportant threats, with decline of the habitat qualityand further loss of habitat. No threats were recorded inthe lower Evros. Conservation recommendations:Water level change causing habitat loss should becontrolled. Detailed information is required on thepopulation size and biology. Remarks: After recordingC. puncticulata from two new localities, Freyhof et al.(2008) suggested changing the status to “vulnerable”.We have recently extend the range of this species to a

Threatened fishes of the world: Pseudophoxinus crassus (Ladiges, 1960) Cyprinidae, from Central Anatolia, Turkey

Common name: Yag baligi (TR). Conservation status: Present status EN (Crivelli 2006), DD since 1996 (Baillie et al. 2004). Identification: Gill rakers 8–9, lateral line scales 72–83, incomplete, with narrow interruptions; D III (IV) 8; last unbranched dorsal ray, not thickened, flexible, A III (7) 8; pharyngeal teeth 5-5 or 5-4; total number of vertebrae 39–40 (Bogutskaya 1992). Living specimens greyish brown on back and flanks and dark yellow on belly. Distribution: Restricted to Central Anatolia, with populations in Tuz Lake tributaries and region of Aksaray and Nigde (Hrbek et al. 2004; Bogutskaya et al. 2006). Found in Kozanli Lake (Konya) and in small creeks near Yenice-Ankara in 2003 (Ekmekci et al. 2009). Habitat and ecology: The maximum age 7; total length 22 cm. Lacustrine, but also observed in deeper parts of slowly flowing creeks with densely vegetated banks. Reproduction: Age of sexual maturity 1 for males and 2 for females. Single spawner, breeding between April and May. Total fecundity to 36,000 at age 6 (Kirankaya et al. 2005). Threats: Water pollution, drought and overfishing (Crivelli 2006). Conservation action: No legal restrictions on the capture of this species. Conservation recommendations: Habitat loss by human activities should be prevented immediately. Fishing should be strictly prohibited. Remarks: The IUCN list (Crivelli 2006) erroneously states that P. anatolicus and P.crassus are found in Saz Lake. Our studies show that the Pseudophoxinus in this lake is P. crassus. Kozanli Lake is also known as Gok Lake or Saz Lake.