Vibriosis is a major disease problem in prawn aquaculture. Until now there has been no clear explanation why some strains of Vibrio are pathogenic, while others are not. This study demon-

No abstract

Bacteriophage therapy has demonstrated promising results towards the control of bacterial infections within the aquaculture industry as an alternative therapy to antibiotics. This current research describes the efficacy of bacteriophage therapy in controlling vibriosis within abalone (Haliotis laevigata). Two bacteriophages were isolated and used in in vitro assays to determine the effect of each specific phage on the growth of specific Vibrio harveyi isolates. To demonstrate efficacy, an in vivo bioassay was performed using abalone (H. laevigata) at a water temperature of 24 °C. Characterisation of the two isolated phages revealed they were from the family, Siphoviridae. The phages had different antimicrobial abilities towards

Ranaviruses can be transmitted by contaminated water and sediment but must retain infectivity for a sufficient period to reach and infect a susceptible host. To determine the risk a virus represents once it enters the environment, its persistence in that environment must be determined. We evaluated the survival of frog virus 3 (FV3) in water and sediment from an English lake at temperatures of 4, 15, 20, and 30 C over time. The virus survived in both water and sediment; however, survival times were significantly lower in sediment. The virus lost infectivity in both matrices with a rise in temperature. In water, time required for a 90% reduction in virus titer decreased from 34 d at 4 C to 5 d at 30 C. In sediment, required time for a 90% reduction decreased from 10 d at 4 C to 1 d at 30 C. These results can be used to estimate the persistence of FV3 in the environment and indicate that the virus could remain infectious in temperate locations for extended periods during winter.