Weight changes and wound healing trend in farmed great sturgeon, Huso huso, following surgical implantation with different levels of 17-β estradiol

A number of management and nutritional strategies are used to induce reproductive maturation and early puberty in sturgeons. Hormonal implants can have a promoting effect on sexual maturation and ovulation in sturgeons, but the surgical procedure for implantation leaves an external injury on the skin leading to further side effects on fish body. In this study, 20 three-year-old great sturgeon (6.9±0.2kg) were maintained in concrete tanks for 168 days and implanted by cutting a small incision on fish abdomen. Implantation capsules contained 0, 3, 6 and 12mg 17-β estradiol (E2) per kg of body weight of fish and administrated each 45 days. The wound index and weight change trend of the implanted fish was evaluated every three weeks after implantation. Results showed that there were no significant differences between implanted fish and control fish in terms of wound healing index and after 3 weeks relative improvement was achieved. Weight change in the first, second and third biometry was not significantly different (P>0.05). However, there was a significant difference in the fourth biometry between E2 implanted fish and control in terms of weight and growth performance indices (weight gain, specific growth rate and condition factor) (P<0.05), but there were no significant differences between fish that was implanted with different levels of E2 (P>0.05). These findings suggest that E2 implantation alters physiological pathways by partitioning energy from muscle growth toward support of maturation-related processes. This study showed that E2 can influence fish weight, but the wound healing process was almost unchanged and independent.