Surgical implantation of electronic tags does not induce medium-term effect: insights from growth and stress physiological profile in two marine fish species

Abstract

Background: Telemetry applied to aquatic organisms has recently developed greatly. Physiological sensors have been increasingly used as tools for fish welfare monitoring. However, for the technology to be used as a reliable welfare indicator, it is important that the tagging procedure does not disrupt fish physiology, behaviour and performance. In this communication, we share our medium-term data on stress physiological profile and growth performance after surgical tag implantation in two important marine fish species for European aquaculture, the sea bream (Sparus aurata) and the European sea bass (Dicentrarchus labrax). Results: Blood samples after surgical tag implantation (46 days for the sea bream and 95 days for the sea bass) revealed no differences between tagged and untagged fish in cortisol, glucose and lactate levels, suggesting that the tag implantation does not induce prolonged stress in these species. Moreover, the specific growth rates were similar in the tagged and untagged fish of both species. Conclusion: Surgical tag implantation does not have medium-term consequences for the stress physiology and growth performance of these two marine fish species in a controlled environment. These observations support the use of accelerometer tags as valuable tools for welfare monitoring in aquaculture conditions. This study also shows that tagged fish can be sampled during experiments and considered a representative portion of the population, as they display growth and physiological parameters comparable to those of untagged fish.

Acoustic Telemetry: A Tool to Monitor Fish Swimming Behavior in Sea-Cage Aquaculture

“…No medical treatment after surgical implantation was used. This tagging procedure and technique has been successfully applied in previous studies on gilthead seabream and documented a good recovery of equilibrium and normal swimming behavior following transmitter implantation, as well as long-term survival and no mid-term stress physiological effects (Arechavala-Lopez et al, 2012;Šegvić-Bubić et al, 2018;Palstra et al, 2019;Alfonso et al, 2020b). In our experiment, tagged gilthead seabream showed 100% short-term survival rate.…”

Calibrating Accelerometer Tags with Oxygen Consumption Rate of Rainbow Trout (Oncorhynchus mykiss) and Their Use in Aquaculture Facility: A Case Study

“…Close to the critical swimming speed, the oxygen diffusion in the tissues (aerobic metabolism) reaches its own maximum velocity, thus limiting the red muscle activation. In contrast, the white muscle was recruited according to a typical exponential pattern (i.e., the white muscle was mostly involved at more elevated swimming speeds and close to the U crit value) [ 35 , 41 ]. The white muscles are mostly linked to the anaerobic glycolysis for energy demand, and thus they are generally used only for short bursts or for rapid acceleration: prolonged activation causes the exhaustion of these muscular fibers.…”

“…The wires were introduced in the needle bending the terminal part for 3–4 mm. Each couple of electrodes, positioned at 1 cm of distance along the longitudinal axis, was then sutured to the left side of the body to minimize entanglements [ 35 , 41 ]. In particular, a suture was placed in the insertion point to anchor the wire while other two sutures were placed on the side of the fish, creating a loop with the wire.…”

“…The specimens were surgically implanted with the acoustic accelerometer V9A (Vemco, Nova Scotia; length: 43 mm; weight: 6.1 g in air and 3.3 g in water) following the procedures described in Alfonso et al [ 41 ]. Briefly the fish were completely anaesthetized with a 50 ppm hydroalcoholic clove oil solution following the same protocol as the one described for EMG implantation.…”

Evaluation of the Effects of the Enriched-Organic Diets Composition on European Sea Bass Welfare through a Multi-Parametric Approach

“…After this period all the fish were considered completely recovered from the surgery [63], and were subjected to a critical swimming speed test (U crit ) in a Blažka style swimming chamber to calibrate EMG signals with the U crit test as described in Carbonara et al [34]. Briefly, U crit is a swimming test in which fish swim in a chamber at increasing speed step (0.1 m s −1 every 10 min) until the fatigue is reached, determining the critical swimming speed of the challenged fish (U crit ) [59].…”