The Gyrodactylus story in Norway

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

“…Malmberg and Malmberg (1993) suggested that G. salaris originated in the Baltic area; it is known to occur naturally at low intensities in this area including the Russian Onega and Ladoga water systems and within some Swedish and Finnish rivers that drain into the Baltic Sea (Ieshko et al, 1996;Shulman et al, 2000). 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).…”

Gyrodactylidae et Gyrodactylose des Salmonidae

“…Thus more than 200 rivers were investigated (TANUM, 1983;HALVORSEN et HARTVIGSEN, 1989) and at the end of 1989 G. salaris was registered in 34 rivers and in about 35 hatcheries, scattered throughout the country (JOHNSEN et JENSEN, 1991). Running expérimental investigations on G. salaris were also initiated in Oslo (TANUM, 1983;BAKKE et al, 1992b).…”

“…In order to clean rivers from G. salaris, ail fish populations of suitable rivers were exterminated by means of rotenon. The rivers were then recolonised by ascending adult salmon (JOHNSEN et JENSEN, 1991).…”

Introduction and spread of non-native parasites withSilurus glanisL. (Teleostei: Siluridae) in UK fisheries

“…Many non-native monogeneans have been recorded in Europe following fish translocations (Johnson & Jensen, 1991;Moravec, 2001;Galli et al, 2003). Although the potential for disease surrounds any parasite introduction (Kennedy, 1994), the risk posed by these monogeneans may be limited due to their purported strict host specificity.…”

“…Examples of disease outbreaks following the introduction of non-native parasites, including a number of monogeneans, are well documented (Johnson & Jensen, 1991;Bauer et al, 2002;Matsche et al, 2010). Many biotic and abiotic factors influence the colonization, establishment and pathogenicity of introduced parasites (Kennedy, 1994).…”