Experimental transmission of epizootic ulcerative syndrome (EUS) in snakehead, Ophicephalus striatus

Abstract

Two separate experiments on transmission of epizootic ulcerative syndrome (EUS) to naive snakehead (Ophicephalus striatus) by cohabitation with EUS-positive snakehead in EUS-enzootic environment and exposure to EUS-enzootic environment alone were conducted in Laguna, Philippines. Under unfed conditions, initial signs of EUS were observed after 9 d of cohabitation and progressed into advanced stages in 10 tol6 d, whereas in exposure to EUS-enzootic environment alone, initial signs were observed in 10 d and developed into advanced stages in 15 to 20 d post-exposure. When food was given, initial signs of the disease were observed after 14 d of cohabitation and progressed into advanced stages in 17 to 20 d, whereas in fish exposed to EUS-enzootic environment alone, onset of EUS was 44 d post-exposure developing into advanced stages in 50 to 55 d post-exposure. Transmission of the disease was 100% in all treatments.