Case Report: Strawberry Disease in Farmed Chilean Rainbow Trout

Abstract

Strawberry disease is a chronic, nonlethal skin condition that affects Rainbow Trout Oncorhynchus mykiss in the United States and several European countries, where it is also known as red-mark syndrome. We provide the first identification and characterization of three strawberry disease outbreaks occurring at two aquaculture farms in southern Chile. Clinically affected fish weighing an average of 400 g presented multiple bright-red, usually raised, skin lesions on the flank, ventral surface, and dorsal surface. A PCR using Rickettsia-like-organism (RLO)-specific primers was performed on nine affected fish, and all skin samples were positive for the RLO 16S ribosomal RNA sequence. All PCR results for Flavobacterium psychrophilum and other bacterial and viral pathogens were negative. Histopathological examination of the skin lesions revealed extensive dermatitis, with severe lymphocytic infiltration in advanced cases. This report is the first to describe strawberry disease in farmed Chilean Rainbow Trout. Additional studies are needed to evaluate the risk for Rainbow Trout culture; fish challenge experiments should be performed to fulfill Koch's postulates and to demonstrate that RLO is the cause of this disease. Received December 27, 2014; accepted October 23, 2015.

First report of Red Mark Syndrome (RMS) in farmed rainbow trout in Slovenia

“…The present case report on RMS in Slovenia, together with the recent demonstrations of RMS in Turkey (Kubilay et al., ), Iran (Sasani et al., ) and Chile (Sandoval et al., ), indicates that the disease is further expanding in Europe and other continents, emphasizing the need of appropriate control measures as well as the collection of epidemiological data.…”

“…Red mark syndrome (RMS) is an inflammatory skin disorder spreading in farmed adult rainbow trout ( Oncorhynchus mykiss ), firstly reported in the UK (Ferguson et al., ; Noguera, ; Oidtmann & Noguera, ; Verner‐Jeffreys et al., , ) and USA (LaPatra, Groff, Lauda, Munn, & Jones, ; Lloyd et al., ; Olson, Beleau, Busch, Roberts, & Krieger, ), then signalled in Finland (Bruno, Crumlish, LaPatra, Noguera, & Verner‐Jeffreys, ), Austria, Switzerland (Schmidt‐Posthaus, Bergmann, Knüsel, Heistinger, & Licek, ), Italy (Galeotti, Giavenni, Volpatti, Beraldo, & Feist, ), Turkey (Kubilay et al., ), Iran (Sasani, Shokrpoor, Rahmati‐Holasoo, & Zargar, ) and Chile (Sandoval et al., ). The disease classical signs have recently been well characterized according to the criteria of Oidtmann et al.…”

First report of lesions resembling red mark syndrome observed in wild‐caught common dab (Limanda limanda)

“…Red mark syndrome (RMS) or cold water strawberry disease is a skin disease observed in farmed rainbow trout ( Oncorhynchus mykiss ). The disease was described for the first time in Scotland (Ferguson et al, ; Verner‐Jeffreys et al, , ) and was, thereafter, reported in various European countries (Ferguson et al, ; Fleury, Vuillaume, & Sochon, ; Galeotti, Ronza, et al, ), Turkey (Kubilay et al, ), Iran (Sasani, Shokrpoor, Rahmati‐Holasoo, & Zagar, ) and Chile (Sandoval et al, ). The disease is very similar to UK strawberry disease and might be regarded as the same (Metselaar et al, ; Oidtmann et al, ).…”

Antibiotic Resistance Genes in Freshwater Trout Farms in a Watershed in Chile

“…Flavobacteriosis was treated with florfenicol. Strawberry disease is thought to be caused by a Rickettsia ‐like organism (Lloyd et al, 2011; Sandoval et al, 2016; Christie et al, 2018) and typically occurs in adults weighing between 200 and 300 g. This disease was treated with florfenicol or oxytetracycline. Antibiotic doses were reported as milligrams of antibiotic per kilogram of fish treated or as grams of antibiotic used per biomass (ton of fish treated).…”