The aim of the study was to determine the optimum concentration of MS-222 for given size groups of pikeperch and water temperatures. The study considered three size groups of pikeperch (body weight [BW] 8.56, 15.72, 52.91 g), an MS-222 water solution (50, 100, and 150 mg/L), and two temperatures (20 or 23°C). It was revealed that the optimum MS-222 concentration depended largely on the size of the pikeperch and on water temperature. For fish with a BW <10 g the recommended concentration is 100 mg/L but only at 23°C. For fish with a BW of 10-40 g at an immersion temperature of 20°C the safe MS-222 concentration ranges from 100 to 150 mg/L. However, at a temperature of 23°C the recommended concentration of the anesthetic is 100 mg/L. Similarly for larger fish, that is, fish with a BW >40 g, the optimum MS-222 concentration at a water temperature of 20°C is in the range of 100-150 mg/L, but at a temperature of 23°C is it approximately 100 mg/L. Additionally, when exposure to the anesthetic is shorter (several min), a concentration of 150 mg/L is also safe for juvenile pikeperch of this size. K E Y W O R D Sanalgesia, anesthetic, phase, pikeperch, recovery, tricaine methanesulphonate

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.

Fisheries Institute in Olsztyn, PolandCitation: Zakêoe Z., Demska-Zakêoe K., Szczepkowski M., Ro¿yñski M., Ziomek E. 2016 -Impact of sex and diet on hematological and blood plasma biochemical profiles and liver histology of pikeperch (Sander lucioperca (L.)) -Arch. Pol. Fish. 24: 61-68.Abstract. The aim of the study was to determine the impact of diet and sex on the hematological and blood plasma biochemical profiles and the liver histology of pikeperch, Sander lucioperca (L.) reared in recirculating aquaculture systems (RAS) (initial mean body weight (BW) 1.35 kg). The proximate composition of the two commercial feeds used were (protein/lipid/nitrogen-free extracts) (P/L/NFE)) P505/L118/NFE294 g kg -1

The aim of this work was to determine the impact of etomidate (Propiscin) dose (1 and 2 ml l -1 ) and exposure time (2 and 10 min) on the biochemical and haematological parameters of juvenile pikeperch (Sander lucioperca) [mean body length (Lc) 25.9 cm; body weight (W) 189.9 g] that were reared in a recirculating aquaculture system (RAS). Significant changes in the mean values of total protein, globulin, calcium, magnesium, and ammonia were noted in all groups immediately following exposure. The greatest changes in the haematological indicators were observed in groups subjected to 10-min exposure at both doses of the anaesthetic. The specimens from these groups had higher values for white blood cells (WBC), red blood cells (RBC), haemoglobin (HGB), haematocrit (HCT), and mean corpuscular volume (MCV). Statistically significant differences in these same parameters were also noted in the groups of fish exposed to the anaesthetic for 2 min at a dose of 2 ml l -1 , but they were not as pronounced. Twenty-four h following exposure to etomidate, all blood parameters in the experimental groups were comparable to those of the control group. Etomidate can be recommended as a safe, effective anaesthetic for pikeperch.

Bacterial diseases are a significant problem in the controlled rearing of fish. Furunculosis (Aeromonas sp.), flavobacteriosis (Flavobacterium sp.), and pseudomonadosis (Pseudomonas sp.) are currently the most frequently identified diseases in recirculating aquaculture systems of various fish species. Such a situation is also observed in pikeperch rearing. Due to the emerging difficulties of effective prophylaxis using commercial vaccines, interest in the use of autovaccinations is increasing, not only in ichthyopathology but also in other veterinary fields. Our research aimed to assess the effect of the vaccination method on the overall condition of the fish and survival after the experimental infection with Aeromonas salmonicida. Pikeperch were vaccinated by (1) bath, (2) a single i.p. injection, or (3) feed. The fish were measured and weighed on day 0 and after 28 and 56 days of the experiment. Specific growth rate, daily growth rate, condition factor, and feed conversion ratio were calculated. On days 7, 14, 21, and 28 of the experiment, ceruloplasmin and lysozyme levels were rated. In addition, a challenge test was performed. The obtained results showed that the method of vaccination is important and affects the growth of fish, the overall condition of fish, and survival after experimental infection.