Performance of fast-absorbable suture and histo-glue in closing incisions in Brown trout

Telemetry has become a standard tool in fish research, but tagging methods still need refinement to achieve better results and to improve animal welfare. One of the problems reported from evaluations of surgical implants is unsatisfactory wound closure. Thus, researchers struggle to find better ways to close incisions, typically for implants of tags under field conditions. Problems are regularly encountered when closing incisions with traditional absorbable or non-absorbable suture, including decreased growth, slow wound healing, erythema and necrosis at sutures. In this study, survival, growth, tag expulsion rate and incision healing was compared among three groups of dummy transmitter-tagged wild brown trout Salmo trutta where incisions were closed with two types of suture material (absorbable vs. fast absorbable) and Histo-glue. The tagged fish were kept in semi-natural ponds for 20 days. Survival did not differ between groups, but growth of the tagged fish was lower than that of the control group. Histo-glue gave the best healing, but resulted in high tag loss rate (33%). The fast absorbable suture did not disappear faster than normal absorbable suture, healing and tag loss was similar. The use of fast absorbable suture may hold potential for improving the procedure and should be further tested