Pressure Effect of Temperature on Koi Herpes Virus Diseases (KHVD) at Koi Fish (Cyprinus carpio koi).

Abstract

Koi fish are susceptible to Koi Herpes Virus Disease (KHVD). The disease is caused by the Koi herpesvirus, and mortality rate up to 80-95% within 2 weeks after infection. Koi herpesvirus is included in the virus that is hexagonal with a diameter of 100 nm. This study aims to determine the effect of temperature stress on the ability of Koi herpesvirus infects KHV free Koi fish and know the nature of transmission. Isolation and identification of Koi herpesvirus originate from the gills of Koi fish organs by the method of polymerase chain reaction (PCR) using PCR-KIT IQ2000TM. In this research, there were 8 fish groups of research, including the 6 fish group of test fish and two control test. The fish were injected with a virus suspension 10% as much as Koi herpesvirus 0.1 ml in intra peritoneal. For 14 days, seven of the first group as a fish's treatment of extreme temperatures at night 18-19 0C and 30-31 0C during the day. The 8th group of fish without control treatment temperature extremes. In a sequence group, the number of fish that were positive of KHVD were 5/5, 7/10, 5/5, 8/10, 0/5, 0/10, 4/5 and 0/5. KHV isolates with codes D143, D144 and M628 extremely virulent KHV isolates and not in the code D139. Stressed fish more susceptible to KHVinfection and KHV-infected fish easily transmit the koi herpesvirus in healthy fish or cohabitation by contamination of water in the aquarium and / or direct contact.