Investigation of the potential of liposome and microparticulate feeds to partially replace microalgae in the nursery rearing of green-lipped mussels (Perna canaliculus)

The seeding of small juvenile green-lipped mussels (Perna canaliculus) onto coastal farms is associated with high losses. These losses can be reduced by seeding larger juveniles; however, the nursery culture of juveniles is unviable because of the high cost of producing live microalgal feeds. In this study, we compared the ability for two diets, a formulated microparticulate feed, MySpat and liposomes fabricated with mussel extract to replace live microalgae at different proportions for feeding small (1.9 mm shell length +/- 0.02 SE) green-lipped mussels. The experimental diets consisted of a mix of live Tisochrysis lutea, Diacronema lutheri and Chaetoceros muelleri that were replaced with increasing proportions of MySpat (25%, 50% and 75%), and liposomes (25% and 50%). There were no significant differences in mortality of mussels relative to the control (100% microalgae) among any of the diet treatments. However, mussel growth tended to decrease with increasing substitution of the microalgal component of the diets. The results from this study suggest that microparticulate and liposome formats provide a viable mode of food delivery to juvenile mussels, with improved formulation of these formats having the potential to lead to the substitution of live microalgal diets which make nursery culture unviable at present.

Automated summary

The study suggests that microparticulate and liposome formats can be viable alternatives to live microalgal diets for feeding small green-lipped mussels, with higher substitution levels leading to reduced growth in mussels.