#Best goldfish aquarium setup serial

Additionally it cannot be excluded until today, that this vaccine might revert or recombine to a more virulent phenotype, because the precise reason for its attenuation is still unclear 10, 12. Unfortunately it seems to be virulent to small carp, weighing less than 50 g 10, 11.

#Best goldfish aquarium setup serial

This vaccine contains live attenuated virus, which was obtained after 26 serial cell culture passages, followed by UV treatment 9. However, one commercial vaccine was produced by the company KoVax in Israel, which was used for carp. Up to now, there is no licenced commercial vaccine available in major parts of the world. Even though all these species can be infected by KHV without showing any clinical symptoms 6, they can transmit infectious KHV to the only known susceptible species for koi herpesvirus disease (KHVD), common carp and the koi 2, 6, 7, 8.ĭue to the high economic impact of KHV, efficacious and safe vaccines are mandatory and urgently needed to protect animal welfare and aquacultures. Moreover, carp are usually held together with other species like tench ( Tinca tinca), crucian carp ( Carassius carassius) or pike ( Esox lucius). These procedures can lead to a re-activation of a persistent infection resulting in tremendous losses in the carp population. At the end, usually after three years of the production cycle, carp are captured by netting and kept in concrete ponds for fastening, until selling. In Germany, it is common practice to transfer carp before winter in deeper ponds for wintering and in spring back to shallow ponds for growing and fattening. This can lead to virus re-activation and to a renewed shedding of infectious virus 5. If carp become latently infected, the virus can be re-activated by stress, for example induced by netting as a part of normal procedures in fish handling.

Once the host is infected, KHV persists in it for the entire life span, like all other herpesviruses 4. Beside high mortality, lifelong persistence or latency and a wide host range for asymptomatic KHV infections are severe problems for carp production and koi breeding worldwide. The virus causes severe fatality rates of up to 100% 2 in both varieties. Since 2000 common carp and koi have been endangered by an Alloherpesvirus, genus Cyprinivirus, named Cyprinid herpesvirus 3 (CyHV-3) or koi herpesvirus (KHV) 2, 3. Beside common carp, the ornamental variety from Japan, the koi, has a growing importance with enormous financial values for hobbyists. Carp production is an important economic factor, especially in Asia, where 4.15 million tons of common carp were produced, that equals 94.12% of global production 1. In 2019 common carp was one of the most produced freshwater fish in the World, with 9.6% of the produced bio mass in aquaculture 1. This was confirmed by the generation of engineered ORF150 deletion mutants of wild-type KHV which exhibited a similar attenuation in vivo.Ĭommon carp ( Cyprinus carpio L.) is one of the most important freshwater fish in the world. The attenuation of the newly generated vaccine was tracked down to a partial deletion of open reading frame 150. Additionally, the vaccine virus allowed differentiation of infected from vaccinated animals (DIVA) by PCR. Vaccination induced no or mild clinical signs and protecting antibodies have been measured. An advantage of boost immunization was demonstrated, especially after oral application. In this study, a live attenuated vaccine virus was generated by cell culture passages of virulent KHV, and shown to protect carp or koi after immersion or oral application against wild type challenge. Therefore, there is an urgent need for new, safe and available vaccines. Unfortunately, there is only one commercial vaccine available which is not approved in most countries.

This induced a high economic impact, since the KHV disease cannot be cured up to now, but only prevented by vaccination. Since the end of the1990ies, Cyprinid herpesvirus 3 (also known as koi herpesvirus, KHV) has caused mass mortality events of koi and common carp all over the globe.