Temporal variation in condition index and meat quality of Lunella undulata (Turbinidae), in relation to the reproductive cycle

ABSTRACT

Lunella undulata is a subtropical-temperate marine gastropod which is harvested commercially from temperate reefs in Australia. This paper aimed to evaluate monthly variation in the condition index (CI) and biochemical composition of the foot tissue of L. undulata in relation to the spawning cycle. The gonadosomatic index (GSI) varied significantly between males and females and across months (P = 0.0001), ranging from 43% to 70% in males and 41% to 71% for females. The highest GSI, as well as the highest CI for both sexes was recorded in December and April, whilst meat yield peaked in January, September and October. Protein, lipid, fatty acid and heavy metals in the foot tissue also significantly varied between months (P < 0.05). Throughout all 14 months of sampling, the foot tissue of L. undulata showed good nutritional quality, with high levels of protein and the polyunsaturated fatty acids, docosapentaenoic acid, eicosapentaenoic acid and arachidonic acid. Overall, despite some temporal variability in the biochemical composition, L. undulata could be harvested at any time of the year for human consumption, although it may be best to avoid peak spawning times, which occur around January in northern NSW.

KEYWORDS:

• Turban snails
• protein
• fatty acids
• trace elements
• reproductive cycle
• Australia

Acknowledgements

The research was supported by postgraduate research funding from the School of Environmental, Science and Engineering and Marine Ecology Research Centre, Southern Cross University. We gratefully acknowledge the Ministry of Higher Education of Malaysia for the PhD scholarship for the first author. We thank an anonymous reviewer for comments on the article. We also thank Roselyn Regino, Komaruddin Toyib, Fathimah Handayani, Dexter de la Cruz, Dwi Puji, Dr. Ajit Ngangbam and Mimi Salmiah for assisting with sample collection. We also acknowledge Graham Lancaster from EAL, SCU for facilitating elemental analyses.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The research was supported by postgraduate research funding from the School of Environmental, Science and Engineering and Marine Ecology Research Centre, Southern Cross University. We gratefully acknowledge the Ministry of Higher Education of Malaysia for the PhD scholarship for the first author.