The key appears to be beneficial bacteria, which wild rock lobster larvae host naturally but which farmed lobsters are missing because they are not exposed to the complex ecology of the ocean environment.
Following several successful AIMS field trips to capture tiny, translucent rock lobster larvae from the Coral Sea, Dr Høj has been able to compare natural microbial communities that live on the wild larvae with the microbes present in experimental farmed animals.
She has found that wild rock lobster larvae do not have the filamentous bacteria found on farmed animals and that compromise their health. Instead, they have small quantities of particular bacteria that appear to be good candidates as probiotics, helping the young lobsters grow rather than inducing disease.
Further work will be directed at understanding these beneficial bacteria and potentially harnessing them as probiotics to be used in growing commercial quantities of the valuable and sought-after seafood.
"Probiotics are beneficial bacteria that you introduce to the aquaculture system to gain an advantage," Dr Høj said. "For example, they might compete with or inhibit the growth of pathogens and thereby promote the growth and survival of the aquaculture target species"
While animal industries often depend upon antibiotics, Dr Høj and her colleagues in the AIMS rock lobster aquaculture team are hoping to increase the sustainability of lobster farming by using probiotics instead. Probiotics are especially beneficial because of rock lobsters’ long larval phase, which makes them liable to infection.
At present, rock lobsters are not able to be sustainably farmed in commercial numbers, although research by AIMS is attempting to make this goal a reality.
Dr Høj and PhD student Evan Goulden are presenting their latest findings on bacteria from wild rock lobster larvae today (Monday 18 August 2008) at the 12th International Society for Microbial Ecology paper at the Cairns Convention Centre. They are two of 22 AIMS scientists attending the event. The leader of AIMS’ marine microbes team, Professor Linda Blackall, chairs the organising committee of the conference.
The conference is being held in Cairns from 17 to 22 August. Visit the conference website for detailed information, including a list of invited expert speakers and their topics: http://www.kenes.com/isme12/