Red mark syndrome (RMS) or cold water strawberry disease (CWSD) is a non-lethal skin disease of rainbow trout Oncorhynchus mykiss that is of high economic importance in the UK. The disease is temperature-dependent, with up to 60% morbidity at water temperatures below 15°C. Although CWSD is horizontally transmissible, the aetiology is still unknown. Here we describe the first cases of RMS on the European mainland in the alpine regions of Switzerland and Austria. In Switzerland, morbidity remained around 1% after the first outbreak, whereas in Austria no further cases were diagnosed.KEY WORDS: Red mark syndrome · Coldwater strawberry disease · Oncorhynchus mykiss · Austria · Switzerland · Water temperature Resale or republication not permitted without written consent of the publisherDis Aquat Org 88: 65-68, 2009 al. 2008). It is notable that Lloyd et al. (2008) also reported no statistical association between SD lesions and F. psychrophilum based on PCR assays, but they did find a strong association between SD lesions and a Rickettsia-like organism. Verner-Jeffreys et al. (2008) proposed that RMS is caused by 1 or more infectious agents with a long latency (> 500 day-degrees).RMS was first reported in 2003 in Scotland. RMS seemed to spread in the UK, as it was subsequently diagnosed in England and Wales (Verner-Jeffreys et al. 2008). Outbreaks outside the UK have not been reported yet. Here we describe the first likely cases of RMS on the European mainland, in 2 Swiss and 1 Austrian trout farm. CASE STUDIES AND DISCUSSIONThe 2 affected Swiss farms exclusively raise rainbow trout. Despite belonging to the same owner, they are completely separated. Farm A consists of a hatchery and a grow-out facility, which are located at 2 different sites with separate water supplies. The farm produces 250 t of trout yr spring water with a temperature of 5 to 14°C. Eggs are supplied by brood stock kept in the grow-out facility. Additionally, each year 2 batches of eggs are imported from different farms in the European Union, but not from the UK. In the hatchery, fingerlings up to 50 g are reared in separate troughs and concrete raceway systems with gravel bottoms. Older animals are moved into the grow-out facility that is supplied by spring water at 250 l s -1 with water temperature of 4 to 14°C. Trout are reared in separate tanks and concrete raceway systems.Farm B produces 100 t of rainbow trout yr -1 hatched on site in recirculation units supplied with tap water. Afterwards, fish are reared in separated flow-through troughs and tanks and then moved to independent recirculation systems. The farm is supplied by 80 to 110 l s -1 spring water flowing in an open channel for about 1 km that is inhabited by wild fish. The water is not disinfected before entering the fish farm. Water temperature ranges from 5 to 15°C. In 2007, rainbow trout from Farm A were once transported to Farm B.Water parameters of both farms were checked regularly and showed no unusual variation. Rainbow trout from both farms regularly tested negative...

Koi carp presenting with coelomatic neoplastic lesions are of growing importance in Switzerland and elsewhere in Europe, as clinical diagnosis is usually difficult and prognosis is usually poor because of late recognition. To gain more information about this condition, between 2008 and 2012, 117 koi diagnosed with coelomatic tumours were included in this study. The nature and growth characteristics of these pathologic tissues were documented. Out of 117 koi, 48.9% (n = 57) were female; the ovary was the most often affected organ (35%, n = 41), and in 62.4% (n =73) of cases, the cells of origin were identified as stromal cells of the sex-cord and the tumours were identified as sex-cord stromal tumours. The characteristics of growth and histology showed that the majority of tumours were malignant.KEY WORDS: Koi carp · Neoplasm · Histopathology · Ovary · Testis · Sex-cord stromal tumour Resale or republication not permitted without written consent of the publisherDis Aquat Org 119: [219][220][221][222][223][224][225][226][227][228][229] 2016 To gain more information about the nature of neoplastic lesions in internal organs and the pathological features of these neoplasms, koi presenting with various abdominal neoplasms were examined between 2008 and 2012. Specifically, possible sex-specific differences, the organs affected, the tissue/cells of origin and the characteristics of neoplastic growth were investigated. MATERIALS AND METHODS Origin of samplesBetween 2008 and 2012, all koi carp with an enlarged abdomen, which were euthanized or died in our veterinary clinic, were examined pathologically. A standard necropsy was performed. Those fish showing a coelomatic mass suspected to be a tumour were included in this study, for a total of 117 animals. As there was no recurrence of tumour masses in the same animal, 1 tumour case always corresponds to 1 animal. If possible, the sex of the affected animal was recorded. Macroscopic changes of internal organs, including extent and appearance of the coelomatic mass (colour, surface, cut section and texture) were recorded in 62 cases. In all 117 cases, tissue samples of different representative areas were fixed and stored in 10% buffered formalin and sent for analysis to the Centre for Fish and Wildlife Health (University of Bern). These samples were identified histologically as coelomatic neoplastic lesions. This criterion was used for the final decision to include the animals in this study. Histopathology and immunohistochemistry (IHC)Formalin-fixed samples were paraffin-embedded and routinely processed. Three or 4 serial sections were prepared: the first sections were stained with haematoxylin-eosin (H&E), the remaining sections were used for IHC staining.As a basis to classify the neoplasms, criteria defined in the World Health Organization classifications for tumours in domestic animals (Kennedy et al. 1998, Head et al. 2003, Meuten et al. 2007) were used.Because of limited availability of antibodies working properly on our koi carp tissue, only an epithelia...

This study compared the results of reverse transcription-polymerase chain reaction (RT-PCR) and traditional virus isolation on cell culture in detection of viral haemorrhagic septicaemia virus (VHSV) and infectious haematopoietic necrosis virus (IHNV). RT-PCR was used for 172 tissue sample pools (total of 859 fish) originating from a field survey on the occurrence of VHSV and IHNV in farmed and wild salmonids in Switzerland. These samples represented all sites with fish that were either identified as virus-positive by means of virus isolation (three sites, four positive tissue sample pools) and/or demonstrated positive anti-VHSV-antibody titres (83 sites, 121 positive blood samples) in a serum plaque neutralization test (SPNT). The RT-PCR technique confirmed the four VHSV-positive tissue sample pools detected by virus isolation and additionally identified one VHSV-positive sample that showed positive anti-VHSV-AB titres, but was negative in virus isolation. With IHNV, RT-PCR detected two positive samples not identified by virus isolation while in these fish the SPNT result had been questionable. One of the IHNV-positive samples represents the first detection of IHNV-RNA in wild brown trout in Switzerland. Compared to SPNT, the RT-PCR method detected, as with virus isolation, a much lower number of positive cases; reasons for this discrepancy are discussed. Our results indicate that RT-PCR can not only be successfully applied in field surveys, but may also be slightly more sensitive than virus isolation. However, in a titration experiment under laboratory conditions, the sensitivity of RT-PCR was not significantly higher when compared with virus isolation.

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Abstract. This report documents 2 cases of branchioblastomas in koi carp (Cyprinus carpio). Macroscopically, both cases were characterized by well-demarcated, pale red nodular masses located at the left first branchial arch and the right pseudobranch, respectively. Histologically, the neoplasias were composed of blast-like cells that differentiated into cartilage and branchial lamellae embedded in abundant fibrous connective tissue. Based on these findings, a branchioblastoma was diagnosed.