Differences between intestinal segments and soybean meal-induced changes in intestinal mucus composition of common carp Cyprinus carpio L.

The alimentary tract is a possible site where pathogens and toxins can enter. The alimentary tract is protected, amongst others, by mucus. In this study, tissue samples and crude mucus preparations from different parts of the intestinal tract of Cyprinus carpio (from intestinal bulb onto the hindgut) were examined using histological, histochemical and biochemical techniques. Furthermore, the response of the intestinal mucosal layer and intestinal mucus of C. carpio to acute soybean meal (SBM)-induced enteritis was investigated. In the present study, an indication for a different protein core of mucus high molecular weight glycoproteins (HMGs) for first and second segment could not be found. However, differences in mucus glycosylation could be found. Along the gut axis, the size of the major protein peaks were not similar, which can be caused by a different glycosylation. Also, differences in staining for the antimicrobial peptide beta-defensin 2 were found. Furthermore, changes in HMGs upon SBM diet were found similar to those found in inflammatory bowel disease (IBD) in humans. Initial changes include: changes in mucin composition, the presence of BD3 and of bacteria in internal organs. After the initial changes, all values measured returned back to the initial pre-SBM diet values

Entwicklung alternativer, ökologisch unbedenklicher, effektiver und für Fische gut verträglicher Bekämpfungsstrategien gegen den Ziliaten Ichthyophthirius multifiliis ohne Einsatz von Therapeutika in Forellenhaltungen (Verbundvorhaben)

Im Rahmen des Projekts AbiAqua konnten neue alternative Strategien zur Bekämpfung der Ichthyophthiriose entwickelt werden. Zum einen wurden Methoden der Transmissionsunterbrechung erfolgreich durchgeführt, zum anderen erwiesen sich zwei Impfstrategien als sehr vielversprechend. Erstmalig konnten chemischen Stimuli identifiziert werden, die infektiöse Ichthyophthirius multifiliis Theronten zur Wirtsfindung und Wirtserkennung nutzen. Die spezifischen Reaktionen ließen sich dazu nutzen, die Schwärmer mittels natürlicher Substanzen zu ungerichtetem Wirtsfindeverhalten zu stimulieren und sie über deren Erkennungsreaktionen in Wirtsnähe an Oberflächen abzufangen. Daneben konnte mittels andauernder Aktivierung und dem damit erhöhten Energieverbrauch der Erregerstadien das Zeitfenster, in dem diese einen neuen Wirt aufgesucht haben müssen, entscheidend verkürzt und die Wirtsinvasion quantitativ minimiert werden. I. multifiliis Schwärmer zeigten nach Zugabe von Aktivierungskomponenten ins Wasser eine verminderte Fähigkeit zur Wirtserkennung. Eine signifikant erhöhte Mortalität der Transmissionsstadien konnte dabei sowohl durch Zugabe von Reinsubstanzen als auch durch Abfangen auf speziellen Fallen-Prototypen erzielt werden. Vom Fisch abgehende Stadien konnten zudem durch Abfangmatten wirkungsvoll entfernt werden. Die Impfung über eine Tauchbadvakzine mit formalininaktivierten I. multifiliis nach Vorbehandlung der Fische in einem Ultraschallbad und die Impfung durch eine intraperitoneale Injektion formalininaktivierter I. multifiliis erwiesen sich als wirksam. Es konnte demnach ein System entwickelt werden, das die Aufnahme des Impfstoffes über die Haut verbessert und so zu signifikant besseren Impferfolgen führt. Die im Rahmen dieses Projektes entwickelten neuartigen Ansätze bieten klare Vorteile gegenüber der direkten Anwendung von Desinfektionsmitteln und Therapeutika in der Speisefischproduktion. Sie sind ökologisch unbedenklich, ökonomisch für den Teichwirt und einfach in der Handhabung. Durch die Entwicklung neuer Ansätze zur Eindämmung der wichtigsten Parasitose in der Aquakultur konnte ein wertvoller Beitrag zum Ausbau der ökologischen Produktion in Deutschland und zu einer Stärkung des Tierwohls in der Fischzucht geleistet werden

Emergence of carp edema virus (CEV) and its significance to European common carp and koi Cyprinus carpio

Carp edema virus disease (CEVD), also known as koi sleepy disease, is caused by a poxvirus associated with outbreaks of clinical disease in koi and common carp Cyprinus carpio. Originally characterised in Japan in the 1970s, international trade in koi has led to the spread of CEV, although the first recognised outbreak of the disease outside of Japan was not reported until 1996 in the USA. In Europe, the disease was first recognised in 2009 and, as detection and diagnosis have improved, more EU member states have reported CEV associated with disease outbreaks. Although the structure of the CEV genome is not yet elucidated, molecular epidemiology studies have suggested distinct geographical populations of CEV infecting both koi and common carp. Detection and identification of cases of CEVD in common carp were unreliable using the original PCR primers. New primers for conventional and quantitative PCR (qPCR) have been designed that improve detection, and their sequences are provided in this paper. The qPCR primers have successfully detected CEV DNA in archive material from investigations of unexplained carp mortalities conducted >15 yr ago. Improvement in disease management and control is possible, and the principles of biosecurity, good health management and disease surveillance, applied to koi herpesvirus disease, can be equally applied to CEVD. However, further research studies are needed to fill the knowledge gaps in the disease pathogenesis and epidemiology that, currently, prevent an accurate assessment of the likely impact of CEVD on European koi and common carp aquaculture and on wild carp stocks

Emergence of carp edema virus (CEV) and its significance to European common carp and koi Cyprinus carpio

Carp edema virus disease (CEVD), also known as koi sleepy disease, is caused by a poxvirus associated with outbreaks of clinical disease in koi and common carp Cyprinus carpio. Originally characterised in Japan in the 1970s, international trade in koi has led to the spread of CEV, although the first recognised outbreak of the disease outside of Japan was not reported until 1996 in the USA. In Europe, the disease was first recognised in 2009 and, as detection and diagnosis have improved, more EU member states have reported CEV associated with disease outbreaks. Although the structure of the CEV genome is not yet elucidated, molecular epidemiology studies have suggested distinct geographical populations of CEV infecting both koi and common carp. Detection and identification of cases of CEVD in common carp were unreliable using the original PCR primers. New primers for conventional and quantitative PCR (qPCR) have been designed that improve detection, and their sequences are provided in this paper. The qPCR primers have successfully detected CEV DNA in archive material from investigations of unexplained carp mortalities conducted >15 yr ago. Improvement in disease management and control is possible, and the principles of biosecurity, good health management and disease surveillance, applied to koi herpesvirus disease, can be equally applied to CEVD. However, further research studies are needed to fill the knowledge gaps in the disease pathogenesis and epidemiology that, currently, prevent an accurate assessment of the likely impact of CEVD on European koi and common carp aquaculture and on wild carp stocks