Fin healing and regeneration in sturgeon

Area of Science:

• Ichthyology
• Fish biology
• Regenerative medicine

Background:

• Pectoral fins are crucial for fish locomotion and stability.
• Understanding fin regeneration is vital for fish conservation and aquaculture.
• Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) pectoral fins have unique structural components.

Purpose of the Study:

• To evaluate the healing process of pectoral fin spines and rays in juvenile Atlantic sturgeon.
• To compare the efficacy of different fin sampling techniques on healing rates.
• To determine the influence of antibiotic treatment on fin regeneration.

Main Methods:

• Juvenile Atlantic sturgeon underwent three pectoral fin sampling procedures: entire leading spine removal, partial spine removal near articulation, or partial ray removal.
• A separate group received no antibiotic (oxytetracycline) after entire leading spine removal.
• Healing was monitored over 12 months via radiographs, histology, and leukocyte counts; survival and growth were also recorded.

Main Results:

• Survival rates were high across all treatments (>99%).
• Leukocyte counts and immune responses were similar between groups, indicating antibiotics did not significantly impact health.
• Radiographs showed slower mineralization in fish with the entire leading spine removed, and even slower healing near the articulation point.
• Histology revealed similar healing patterns for spines and rays, characterized by periosteal osteogenesis.

Conclusions:

• Fin regeneration in Atlantic sturgeon is dependent on the extent of tissue removed, with more extensive injuries requiring longer healing times.
• The location of injury, particularly near the fin's articulation point, influences mineralization rates.
• Antibiotic treatment did not demonstrably affect the healing or survival of juvenile Atlantic sturgeon in this study.