Australian prawn production at around 22 kilotonnes is valued in excess of $250 million. Clearly, the prawn fishery is an important natural resource for Australia that is also the basis for a significant export industry. In addition, prawn aquaculture is a significant industry in northern Australia and accounts for around 14% of the total volume of Australian prawn production. Infectious myonecrosis is a viral disease that has caused significant disease outbreaks and mortalities in farmed Penaeus vannamei in Brazil and South-East Asia, including Indonesia. While P. vannamei is considered the principal host, experimental infection of P. stylirostris (Pacific blue shrimp) and P. monodon (black tiger shrimp) has been reported. The susceptibility of other shrimp/prawn species is unknown. Information on the susceptibility of prawn species important to Australia, including banana prawns (Fenneropenaeus merguiensis), brown tiger prawns (P. esculentus) is lacking. This project would provide information on the susceptibility of two important species of Australian prawns to exotic IMNV. Such information is important to policy-makers, regulators and primary producers with respect to relevant biosecurity issues at all levels of government.

Currently, diagnosis of abalone ganglioneuritis associated with infection by the recently discovered herpes-like virus is dependent on visualisation of gross clinical signs at the macroscopic level, of histological lesions at the light microscopic level and of virus particles at the electron microscopic level. Thus, while detection of diseased abalone is relatively straightforward it is labour-intensive and time-consuming. The purpose of this project is to develop molecular diagnostic procedures for the rapid, sensitive and specific detection and identification of abalone herpes-like virus infections in the presence, or absence, of clinical signs. Thus potential broodstock that are apparently healthy can be screened for the presence of herpes-like virus, sub-clinical, infections prior to on-farm use.

In addition to surveillance tools for detection and identification of sub-clinical infections, better procedures/reagents for overt disease diagnosis are required. While the presence of histological lesions provides a presumptive diagnosis, the development of in situ hybridisation probe(s) and/or diagnostic antiserum for the localisation of abalone herpes-like virus within histological lesions will provide a means for definitive diagnosis to be made with increased confidence.

Furthermore, in addition to providing an enhanced capability and capacity for disease diagnosis (detection and identification of herpes-like virus), development of molecular reagents and procedures will assist future research aimed at better understanding the pathogenesis (e.g. tissue distribution of the virus, effect of host factors such as age) and epidemiology (e.g. determination of host and geographic ranges, modes of transmission) of this disease. Such knowledge is crucial for efficient management of current and future disease outbreaks.