Gross and histologic evaluation of 5 suture materials in the skin and subcutaneous tissue of the California sea hare (Aplysia californica).

Invertebrates are increasing in their importance to both the public and private aquarium trade and play a vital role in biomedical research. Surgical techniques have become an important approach to obtaining data and maintaining good health in both of these areas. However, studies examining tissue reaction to suture material in invertebrates are lacking. The current study evaluated the gross and histologic reaction of Aplysia californica to 5 commonly used suture materials, including polydioxanone, black braided silk, polyglactin 910, monofilament nylon, and monofilament poliglecaprone. Histologic samples were graded on the amount of edema (score, 1 to 4), inflammation (1 to 4), and granuloma formation (1 to 4) present, and a final overall histology score (1 to 6) was assigned to each sample. Compared with untreated control tissue, all suture materials caused significantly increased tissue reaction, but the overall histology score did not differ among the suture materials. Silk was the only suture that did not have a significantly increased granuloma score when compared with the control. Although none of the suture materials evaluated seemed clearly superior for use in Aplysia, we recommend silk because of its less robust granuloma induction, which is favorable in a clinical and research setting.