Abstract

Grafting surgery, a key step in pearl culture process, can trigger physiological, antioxidant, and immune responses in the host mollusk. Adult red abalone (Haliotis rufescens) were subjected to four experimental treatments: (1) anesthesia only (AN); (2) anesthesia plus a surgical incision (IN) in the abdominal wall without mantle grafting; (3) anesthesia, incision, and placement of an autograft (AT); and (4) anesthesia, incision, and placement of an allograft (AL). The control group (CT) consisted of unmanipulated abalone. Hemolymph samples were collected during the recovery phase at 2, 4, 24, and 48 h post-grafting. In both the cell-free hemolymph fraction (CFH) and lysed hemocytes (LH), total protein (TP) content, superoxide dismutase (SOD), catalase (CAT), and myeloperoxidase (MPO) activities, as well as nitric oxide (NO) production and total hemocyte count (THC), were quantified. SOD activity increased across all treatments at 48 h, whereas CAT activity was elevated only in the AL group at 2 and 4 h and in the AT group at 24 and 48 h. THC increased rapidly in the AL group (2 h), followed by increases in the IN and AT groups (4 h), with gradual declines observed by 48 h. Immunological parameters (MPO and NO) were detected primarily in the AL group at nearly all time points. The results of this study demonstrate marked modulation of antioxidant and immunological parameters at both humoral and cellular levels in response to grafting, particularly in the AL and AT groups. Importantly, the immunological activation observed in the AL group was confined to the early post-operative period (48 h) and did not compromise survival, as no mortality was recorded in any experimental treatment. These findings support the feasibility of allografting as part of pearl culture protocols in H. rufescens.