Abstract: The present study was conducted to identify the parasitic infections of Piscicola geometra, on three different species of Cyprinidae in two reservoirs of the Euphrates-Tigris basin, Turkey. The investigation was carried out from May to November, 2013 for Dumlu creek and from September, 2014 to April, 2015 for Goynük stream. Fourteen parasites were recorded on seven of the 94 examined fish specimens. This study is to be the first record of P. geometra parasitizing on Capoeta capoeta, Alburnus mossulensis and Cyprinion macrostomum for freshwater fish parasite fauna.
INTRODUCTION
The host fishes Capoeta capoeta, Cyprinion macrostomum and Alburnus mossulensis live in inland water of Eastern Turkey. Of these two species (C. macrostomum and A. mossulensis) are endemic in Euphrates and Tigris river system (Kuru, 2004). In general leeches (Hirudinea, Piscicolidae) are well known as ectoparasites and they are found nearly anywhere on the external body surface of fish. According to Epstein (2013) the first characteristic of the fish leeches of Palearctic was presented in the key to leeches by Johansson (1896) with additions. This work gives brief appearance characteristics of Piscicola geometra. The family Piscicolidae (fish leeches) introducing to the fish parasite fauna, began from publication of Johansson (1896) about "Necessity of studying the anatomy of the fish leeches to construct their classification".
Fish leeches can cause a negative effect on a host health. Undoubtedly, ulceration, hemorrhage and inflammation associated with leech attachment sites weaken the host and may predispose hosts to bacterial infections, tissue damage, osmoregulatory problems and act as vectors of pathogens (Ahne, 1985; Burreson, 2006). Piscicola geometra prefers oxygenated waters, mainly wave-washed shores of lakes and in fast-flowing streams and rivers. The aforementioned leeches use an reversible proboscis to penetrate the tissues of the host in order to suck their blood. This kind of leeches can move easily in most cases firmly attaches itself towards the gills or the base of host fins, where it remains for several days until it is satiated and then simply drops off. They can stay as a hunger for a long time.
| Table 1: | Piscicola geometra detected on some freshwater fish in Turkey |
A satiated adult can remain unfed for 3-4 months in temperatures of 10-15°C or even as long as 6 months in temperatures as low as 6°C (Mann, 1962). According to Arslan and Oktener (2012) to date, from the parasitic leech species P. geometra has been studied from eleven freshwater host fishes in Turkey (Table 1).
The aim of present study was to investigate and identify of P. geometra on some freshwater Cyprinid fish, naturally living in Dumlu creek (Karasu River, Erzurum) and Goynük stream (Bingol) from Euphrates-Tigris basin in Turkey.
MATERIALS AND METHODS
Ninety four samples were caught with gill nets (22-24 mm width) and casting nets, from May, 2013 to November, 2013 at Dumlu creek on Erzurum-Artvin Highway 21th km (40°01'52''N, 41°18'49''E, 1763 m) and from September, 2014 to April, 2015 at Goynük stream, Bingol (38°77'74"N, 40°57'70"E, 992 m) of Euphrates-Tigris basin, Turkey. The sampling area is shown in Fig. 1. Leeches has been examined with stereo microscope to identify the occurrence of P. geometra. The parasites were removed with the aid of some tools. First, they were kept in a refrigerator at+4°C for one day to resting and then killed in warm formaldehyde solution of 4% (not boiled), preserved in 70% ethanol for later examinations. Total length and total weight of examined fish and total number of parasites were recorded. Identification of P. geometra species was made based on Burreson (2006). The parasite on host fish was also photographed.
RESULTS
According to the available literature data, 11 host freshwater fish species were infected with this parasite in Turkey given before. In this study, totally 94 host sample were caught, 24 specimens from Dumlu creek and 70 specimens from Goynük stream. The fish were weighed, measured and examined for the presence of any parasites. Piscicola geometra was detected on the gill of Capoeta capoeta and the other fish (Alburnus mossulensis and (Cyprinion macrostomum) on dorsal, ventral, anal and caudal fins and totally eleven parasite samples were recorded (Fig. 2 and 3). During the study from Dumlu creek and Goynük stream infested fish were found at early spring and autumn seasons. In this time water average temperature in November was 21°C for Dumlu creek and 14°C in March for Goynük stream. The detail data for this study are given in Table 2.
| Fig. 1: | Study sampling sites of Dumlu creek and Goynük stream from Euphrates-Tigris basin, Turkey |
| Fig. 2: | Piscicola geometra on anal fin of C. macrostomum |
| Fig. 3: | Piscicola geometra on caudal fin of A. mossulensis |
| Fig. 4: | Piscicola geometra total view |
| Table 2: | Piscicola geometra on some Cyprinid fishes from Euphrates-tigris system Turkey |
| MW: Mean weight, ML: Mean length, SE: Standard error, NIF: Number of infected fish, NTP: Number of total parasite | |
DISCUSSION
The parasitic leech fauna in aquatic ecosystems still has not been studied sufficiently in Turkey and further studies are necessary. Only there are a few records for P. geometra from the eastern and southern parts of Turkey. It is necessary to intensify the studies on parasitic leeches from various lentic or lotic habitats of these different regions of Turkey. Piscicola geometra studies in Turkey were reported in only some fish species belonging to Cyprinidae and Esocidae families. Studied fishes (C. capoeta, C. macrostomum and A. mossulensis) in this study are also from Cyprinidae family. In this study, P. geometra was given as a first record in three fish species from two different locations (Dumlu creek and Goynük stream). Karatoy and Soylu (2006), in Terkos lake, detected the infestation rate of P. geometra on A. brama resembles to that of this study. Up to the present, P. geometra records in Cyprinus fishes in Turkey were only reported by Oktener et al. (2007) and Demirtas and Senel (2012a) in Çavuşçu and Terkos lakes, respectively. Average annual infestation percentages for aforementioned fish (C. carpio) were 8.3% in Çavuşçu Lake and 25.9% in Terkos Lake, the percentage reached up to 50% in August with the maximum value. These results for C. carpio differed from both our study and data from the other studies related to this parasite.
However, in the same study for Tinca tinca were accorded with our study. Because, parasitism of P. geometra in fishes was generally reported in seasons that have low water temperature and high dissolved oxygen rate (Mann, 1962). The present study accorded with Table 1 except for C. carpio in Terkos Lake (Demirtas and Senel, 2012a). Infestation rates for P. geometra were given from some foreign countries. Willomitzer (1980) worked on Ctenopharyngodon idella in Yugoslavia, Opara and Okon (2004) on Oreochromis niloticus, which was cultured in South-eastern Nigeria Rainforest ponds and Rolbiecki et al. (2009) on a lake-trout (Salmo trutta lacustris), Bielecki and Dzika (2000) on roaches (R. rutilus)From the lake Ukiel, in Poland.
This study was carried in May, 2013 to November, 2013 in Dumlu Creek and in September, 2014 to April, 2015 in Goynük Stream and first records were given for P. geometra in three fish species (C. capoeta, C. macrostomum, A. mossulensis) these belong to Cyprinidae family and we encountered with this parasite only in spring and winter months.
Finding of this parasite in A. mossulensis in Goynük Stream on winter season could be proceeded from continually contributing of thermal waters that sustains the temperature of this water source above +10°C. According to the literature review, when leeches live freely, they prefer demersal area of the water and this situation depends on seasonal changing. Mann (1962), therefore, they cannot be detected in highest temperature months of summer and in winters when the water is quite cold, except some fish (C. carpio and A. brama). These reasons indicate that P. geometra has no parasitic effect on fish when the season is too hot and too cold.
Present study shows that P. geometra, on three different species of Cyprinidae (C. capoeta, C. macrostomum and A. mossulensis) in the Euphrates-Tigris basin for the first time. Up to this day according to the obtained literature data, 11 host freshwater fish species were infected with this parasite in Turkey given before (Table 1). This study is given in addition to previous studies (Fig. 4).
ACKNOWLEDGMENT
The author is very grateful to Prof. Dr. N. Sağlam from Department of Aquaculture and Fish Diseases, Faculty of Fisheries Elazığ-Turkey for his verification for of P. geometra and also thanks to Dr. T. Şisman for the samples from Dumlu creek (Erzurum).