Observations on the process of wound repair in penaeid shrimp

The Petersen disk tag is a standard mark for penaeid shrimp, and attachment of the tag involves the insertion of a stainless steel pin through the shrimp's abdomen, resulting in a relatively large puncture wound. The wound healing process first observed at 24 hr post-tagging showed a pronounced hemocytic infiltration of the wound area. Hemocytes in contact with the pin became fusiform, began adhering to one another, and formed several concentric layers around the pin. Scattered foci of bacteria or nercrotic tissue in the vicinity of the would also became encapsulated by concentric layers of fusiform hemocytes, thereby forming nodules. Melanin appeared in association with the layers of hemocytes nearest the pin and in the nodules. Hemocytic infiltration was lollowed by the appearance of fibrocytes and the deposition of collagenlike fibers along the would channel 48 hr after wounding. Involution of epidermis and consequential cuticular involution into the would channel began at 96 hr after wounding. Complete epidermal and cuticular formation along the wound occurrd by 384 hr post-tagging.