The protozoan, Marteilia sydneyi, is responsible for massive outbreaks of disease and death in commercal rock oysters. This was first recorded in the digestive gland of sick oysters from Moreton Bay, Queensland.

Protozoans

Dr Robert Adlard

Section

Protozoans are microscopic organisms that occur in every environment. Many species of Protozoa live in, or on, other animals with many being parasitic. These species are responsible for more human suffering and death (e.g. malaria) than any other cause, including warfare.

Our current work

• The curator (Dr Rob Adlard) and his collaborators and students are currently researching blood parasites (e.g. avian malaria) from Australian birds. The initial phase is to determine the identity and extent of parasites in birds in SE Queensland, with studies elsewhere in Australia planned for the future.
• A current major project is underway on the commercial oyster parasite, Marteilia sydneyi, the cause of QX disease in Sydney rock oysters. This is a collaborative project funded by the Commonwealth in an attempt to more effectively manage, and hopefully limit, the spread of the disease on the east coast of Australia. * In collaboration with Dr Mike Kent from Oregon State University, USA, Dr Rob Adlard is studying emerging pathogens of finfishes, with a focus on those that cause death or marketability problems in commercial fish species.

  Significance

  The research into bird blood parasites will help in our understanding and control of diseases infecting Australian wildlife. This work is also investigating the transmission dynamics of diseases that are passed from animal to animal by insect vectors.

  The project on oyster pathogens will provide the basis for management of disease in the commercial oyster industry and provide a transparent health audit for oyster stock destined for international export.

  The study on emerging fish pathogens will provide information on the geographic distribution of these pathogens, and their taxonomic affinities and a rationale for allowing/disallowing the importation of fish based on the potential for introducing exotic disease.

  Guide to the collections

  Our major collection of protozoan parasites is the International Reference Centre for Avian Haematozoa (IRCAH), with over 60,000 specimens of thin blood smears taken from birds from nearly every country in the world. Other significant material includes specimens from the School of Tropical Medicine formally located in Townsville and specimens deposited by Josephine Mackerras.

  FAQ

  Q: I have a goldfish covered in white spots. What are they and how do I treat them?
  A: The 'white spots' are a protozoan parasite that lives in the skin of the fish and is covered with microscopic hairs (=cilia). Numbers will build up to such an extent that most infected fish will die. The scientific name of the organism is "Ichthyopthirius multifiliis" and the disease referred to variously as 'ichthyopthiriasis', 'freshwater white-spot disease', or 'Ich'. It can be treated quite easily by the application of a commercially available 'white-spot cure', which normally will contain copper sulphate and be added to the water in the aquarium at low concentrations (e.g. 4 parts per million). Prevention is always better than cure, so it is wise to quarantine any new fish (or plants) in a small aquarium prior to introducing them into a display tank.