Comparative regeneration of excised mantle tissue in one year and seven year old Indian pearl oyster, Pinctada fucata (Gould) grown under land-based culture system

Abstract

Excised mantle tissue (saibo) from the donor oyster is one of the important factors determining quality of cultured pearls. The present study was conducted to compare the process of regeneration of excised mantle tissue in one year and seven year old donor oysters, Pinctada fucata grown under land-based culture system. Menthol was used as relaxant prior to excision of mantle tissue, which was found to be effective at a concentration of 500 mg l-1. The mantle tissue was found to regenerate within 3 months post-excision in both one year as well as seven year old P. fucata, with 100% survival. On gross examination, the regenerated mantle tissue of the 1 year as well as the 7 year old oysters appeared similar to that of the normal mantle tissue of the control group. Histological analysis demonstrated complete regeneration of the mantle tissue and its associated structures in both the groups. This is the first description of in vivo mantle regeneration in 7 year old pearl oyster, P. fucata. The findings revealed that even aged donor oysters yielding good quality saibo can be recovered after mantle excision and could be further used as saibo donors for quality pearl production.