Mantle transplantations in freshwater pearl mussels in Thailand

Allograft and xenograft mantle transplantations were studied in three species of freshwater pearl mussels, Hyriopsis (Limnoscapha) myersiana, H. (L.) desowitzi and Chamberlainia hainesiana, by transplanting foreign mantle tissue into the mantle tissue of a host mantle. The pearl sac is completely formed within 15 days after an allograft. After a xenograft from a C. hainesiana donor into a H. (L.) myersiana recipient, it took 13 days, and in the opposite case it took 15 days. For a H. (L.) desowitzi donor, it took 21 days in a C. hainesiana recipient and 27 days in a H. (L.) myersiana recipient. When the recipient was H. (L.) desowitzi, no pearl sac was observed after xenografts from either of the other two mussel species. Allografts of C. hainesiana and H. (L.) myersiana yielded the highest success rate of forming pearl sacs (96 and 97% respectively). Xenografts from a C. hainesiana donor into an H. (L.) myersiana recipient yielded 94%, and the opposite case yielded 90%. The first completed pearl layer was found for xenotransplantation into a C. hainesiana recipient from an H. (L.) myersiana donor at 126 days after transplantation.