The Gyrodactylidae fauna of rainbow trout Oncorhynchus mykiss Walbaum 1792 in the Rogg breeding pound in Bavaria, Germany

Abstract

In July 2005, 107 rainbow trout in age 1+ from a salmonid farm in Southern Germany situated in the southern tributary area of the Danube river were examined. The aim of this study was to determine the gyrodactylid species found on rainbow trout and to identify their location on the host's body. In total, 291 specimens from genus Gyrodactylus were collected. The most abundantly occurring species was Gyrodactylus truttae (181 specimens), whilst the others were less abundant. For the first time in Germany, Gyrodactylus teuchis and Gyrodactylus derjavinoides on rainbow trout were found. Most parasites occurred on the pectoral and ventral fins. Few specimens were found on the anal or caudal fins, in the oral cavity or on the gills. The only uninfected place was the nasal cavity.

The first report of Gyrodactylus salaris Malmberg, 1957 (Platyhelminthes, Monogenea) on Italian cultured stocks of rainbow trout (Oncorhynchus mykiss Walbaum)

“…This survey together with recent studies on gyrodactylids in rainbow trout farms in Europe (e.g. Rokicka et al, 2007;Dzika et al, 2009) points to the importance of this industry for spreading of G. salaris in Europe. It seems more than likely that the examination of rainbow trout farms in other countries will extend the range further.…”

“…Throughout Europe, G. salaris has also been reported from Norway (Johnsen and Jensen, 1991;Johnsen et al, 1999), from rivers on the Swedish west coast Alenä s, 1998), Denmark (e.g. Buchmann and Bresciani, 1997;Buchmann et al, 2000), Finland (Rimaila-Pä rnä nen and Wiklund, 1987;Kerä nen et al, 1992;Koski Malmberg, 1995;Koski, 1996;Rintamä ki-Kinnunen and Valtonen, 1996), Russia (Ergens, 1983;Ieshko et al, 1996Ieshko et al, , 1997Meinilä et al, 2004), Germany (Lux, 1990;Dzika et al, 2009), Spain (Malmberg, 1993), France (Johnston et al, 1996) and, most recently, from Poland (Rokicka et al, 2007). While the presence of G. salaris has been confirmed by molecular methods for many of these, the reports from certain countries, i.e.…”

Geographical distribution of Gyrodactylus salaris Malmberg, 1957 (Monogenea, Gyrodactylidae)

“…In 2003, however, Cunningham et al [23] acquired a single specimen from a rainbow trout farm in Berlin and confirmed it as being G. salaris by analysis of the ribosomal ITS and IGS region. In 2005, Dzika et al [96] sampled a rainbow trout pond at Rogg in Bavaria, on a tributary of the Danube River, and reported finding G. salaris alongside G. derjavinoides Malmberg, Collins, Cunningham et Jalali, 2007, G. truttae Gläser, 1974 and G. teuchis. The accuracy of the G. salaris drawings, notably those of the marginal hooks, questions the validity of the identification of the specimens in this particular study, given that no reference specimens were deposited in a national collection, nor was molecular analysis conducted.…”

Morphometric and molecular characterization of Gyrodactylus teuchis Lautraite, Blanc, Thiery, Daniel & Vigneulle, 1999 (Monogenea: Gyrodactylidae) from an Austrian brown trout population

“…G. teuchis was reported from wild salmon and trout populations along the European Atlantic coast (Lautraite et al 1999;Cunningham et al 2001;von Gersdorff Jorgensen et al 2008). Based on this distribution it was speculated that the species could originate either from an Iberian refugium or from the Channel River system (Bakke et al 2007), However, the species wide host range and in particular its affinity to rainbow trout has likely enhanced its European spread through aquaculture and it was reported also from fish farms in Czech republic (Matejusova et al 2001), Poland (Rokicka et al 2007), Germany (Dzika et al 2009) and Italy (Paladini et al 2009). To date, G. teuchis has not been reported from wild salmonids in the UK or Fennoscandia (i.e.…”