Effects of 2-phenoxyethanol anaesthesia on sheatfish (Silurus glanis L.)

Abstract

The aim of the study was to investigate the acute toxicity of 2-phenoxyethanol to sheatfish, and using the values of haematological and biochemical profiles of blood and histological tissue examinations to assess the effects of the fish exposure to that anaesthetic. The values of acute toxicity of 2-phenoxyethanol to sheatfish were found to be 10minLC50 0.77 ml/l, 10minLC0.1 0.42 ml/l, 10minLC99.9 1.90 ml/l, 96hLC50 0.29 ml/l, 96hLC0.1 0.20 ml/l, and 96hLC99.9 0.41 ml/l. The 10-min exposure to 2-phenoxyethanol at a concentration of 0.30 ml/l caused significantly higher values (<i>P</i> < 0.05) of packed cell volume (PCV), mean corpuscular volume (MCV), glucose (GLU) and albumins (ALB) immediately after anaesthesia. A significant decrease (<i>P</i> < 0.05) in the level of alanine aminotransferase (ALT) and a significant increase (<i>P</i> < 0.05) in the values of mean corpuscular haemoglobin concentration (MCHC) were found 24 h post anaesthesia. Histological examinations showed capillary ectasia of gill filaments immediately after 2-phenoxyethanol anaesthesia. Twenty-four hours after anaesthesia, no ectasia was observed. No histopathological changes were demonstrated in other tissues (liver, spleen, cranial and caudal kidneys) following anaesthesia. The results of examinations suggest that the use of 2-phenoxyethanol at a concentration of 0.30 ml/l does not cause any irreversible damage in sheatfish.

The effects of four anaesthetics on haematological and blood biochemical profiles in vimba bream, Vimba vimba

“…However, our data differ with findings reported in other species of fish. Velisek et al (2007) observed changes in MCHC and PCV with 2-phenoxyethanol anaesthesia on European catfish. Similar results were obtained by Kristan et al (2012) in their study of the effects of anaesthesia on pikeperch (Sander lucioperca).…”

“…Gomulka et al (2008) also reported decreased ammonia levels in Siberian sturgeon (Acipenser baerii) after eugenol (0.075 ml/l) and MS 222 (125 mg/l) anaesthesia. No changes in the levels of ammonia in rainbow trout, carp, European catfish, or perch following clove oil (30 mg/l) and 2-phenoxyethanol (0.30 ml/l) anaesthesia were observed by Velisek and Svobodova (2004a), and Velisek et al (2005bVelisek et al ( , 2007Velisek et al ( , 2009). Our differing results may be associated with the concentrations of the tested substances and the fish species used.…”

“…On the other hand, Iversen et al (2003) found no change in blood glucose concentrations in Atlantic salmon (Salmo salar) following clove oil anaesthesia. Velisek and Svobodova (2004a) and Velisek et al (2007) also found no changes in the concentration of glucose in common carp and European catfish following 2-phenoxyethanol (0.30 ml/l) anaesthesia. The increases in blood glucose concentrations found in the present study reflected the response of anaesthetised fish to metabolic stress.…”

“…Haematological and biochemical profiles are frequently used for evaluation of the effect of anaesthetics (Iwama et al 1989;Velisek and Svobodova 2004a,b;Velisek et al 2005aVelisek et al ,b, 2006Velisek et al , 2007Velisek et al , 2009Velisek et al , 2011Kristan et al 2012). To our knowledge, no other data on biochemical and haematological profiles in vimba bream anaesthetized with MS 222, Propiscin, 2-phenoxyethanol, or clove oil are available.…”

“…A variety of anaesthetics with differing properties have been used in aquaculture (Cho and Heath 2000;Kazun and Siwicki 2001;Velisek and Svobodova 2004a,b;Velisek et al 2005aVelisek et al ,b, 2006Velisek et al , 2007Velisek et al , 2009Velisek et al , 2011. Chemicals used in aquaculture are subject to strict control, particularly with regard to safety and efficacy (Taylor and Roberts 1999).…”