The aim of this work was to determine the impact of surgically implanted telemetry transmitters (TTs) on the growth, survival, hematological and biochemical indexes, and wound healing in juvenile pikeperch (Sander lucioperca) (body weight 60–90 g). Two incision suturing methods were used—silk sutures (experiment I—group ST) or tissue adhesive (experiment II—group GT). After tagging, the fish were held in a recirculating system for 35 days. No statistically significant differences were noted in the growth or condition indexes analyzed among the fish tagged with TT compared with those from the control groups (untagged). Substantial individual variability was noted, however, in the parameters examined in both the control and tagged groups. Among the hematological indexes, statistically significant differences were only noted in experiment I. Lower values of mean corpuscular volume and mean corpuscular hemoglobin were noted in group ST. Among the biochemical parameters, creatinine was statistically significantly threefold lower, magnesium and alkaline phosphatase (ALP) levels were lower, and ammonia levels were higher in group ST than in the control group. In experiment II, significant differences were only noted for ALP. Tissue adhesive was the superior and more effective method for closing the incision after TT implantation in juvenile pikeperch. This type of suturing facilitated faster healing, and it had less of an impact on juvenile pikeperch welfare.

The aim of the study was to describe the course and timing of the different stages of anesthesia induced with Propiscin (etomidate) on juvenile European perch (experiment I) and to describe the effect of immersing specimens of this species had on selected hematological and biochemical parameters (experiment II). The study was conducted on material with body weights (BW) of 162.98 (experiment I) and 171.60 g (experiment II). In experiment I, general anesthesia was induced with two different anesthetic concentrations (1 or 2 ml l−1; anesthesia time 10 min). In experiment II, blood was drawn for hematological and biochemical analyses from the fish that had been exposed to anesthetic immersion baths with two different concentrations of Propiscin (1 and 2 ml l−1) and for different exposure times (3 and 10 min). Blood samples were collected immediately following immersion (0 h) and 24 h later (24 h). Specimens that were immersed at the higher concentration of anesthetic achieved subsequent stages of general anesthesia two times faster (P ≤ 0.05). However, during recovery, some statistically significant differences were observed, but these lasted only until stage I was achieved. Among the hematological parameters (0 h), significant differences were observed in hematocrit (HCT) and mean corpuscular volume (MCV), while among the biochemical determinations (0 h), statistically significant differences were noted in the concentrations of glucose, calcium, lactate, and ammonia. After 24 h, the levels of these parameters in all fish groups returned to initial values. The hematological and biochemical tests conducted permit concluding that the anesthetic tested, at the concentrations (1 and 2 ml l−1) and the exposure times of up to 10 min at which it was tested, is safe and can be used successfully to induce general anesthesia in perch.

Research focusing on the effects of chemotherapeutics on the physiological state of fish determines their application in aquaculture. The aim of the study was to determine the impact of sodium chloride (NaCl) and/or copper sulphate (CuSO4) on the hematological and biochemical parameters of the blood plasma of pikeperch, Sander lucioperca, (body weight − 346.42 ± 44.82 g; body length − 29.8 ± 1.3 cm) during rearing in recirculating aquaculture systems (RAS). Three groups of fish were subjected to treatment with NaCl (5 g/L), CuSO4 (1.5 mg/L), and NaCl+CuSO4 (5 g/L + 1.5 mg/L). Blood was drawn 0, 24 and 48 h following immersion. Significant differences were noted immediately following the conclusion of immersion: mean corpuscular volume (MCV; elevated values in the NaCl+CuSO4 group) and mean corpuscular hemoglobin concentration (MCHC; elevated values in the NaCl group). Immediately following fish exposure in all three experimental groups (0 h), significantly elevated glucose and lactic acid levels were recorded as were lowered levels of chloride ions (Cl−). After 24 and 48 h, significant differences were observed in Cl−. In the NaCl group lowered levels of this parameter were sustained after 48 h, while in the other two groups this was sustained for 24 h. It was confirmed that the physiological impact on the pikeperch of the prophylactic bath in sodium chloride and/or copper sulphate was short and that the treatments did not have a significant impact on the health condition of pikeperch.