Effect of anaesthesia with clove oil in fish (review).

Clove oil is an effective, local and natural anaesthetic. Many hatcheries and research studies use clove oil to immobilize fish for handling, sorting, tagging, artificial reproduction procedures and surgery and to suppress sensory systems during invasive procedures. Clove oil may be more appropriate for use in commercial aquaculture situations. Improper clove oil use can decrease fish viability, distort physiological data or result in mortalities. Because animals may be anaesthetized by unskilled labourers and released in natural water bodies, training in the proper use of clove oil may decrease variability in recovery and experimental results and increase fish survival. Here, we briefly describe many aspects of clove oil, including the legal uses of it, anaesthesia mechanism and what is currently known about the preparation and behavioural and pathologic effects of the anaesthetic. We outline methods and precautions for administration and changes in fish behaviour during progressively deeper anaesthesia and discuss the physiological effects of clove oil, its potential for compromising fish health and effectiveness of water quality parameters.

Effect of copper sulfate on the survival and growth performance of Caspian Sea kutum, Rutilus frisii kutum.

The aim of present study was to determine the LC50/96 h value of copper sulfate and determine the growth performance of Caspian Sea kutum) Rutilus frisii kutum (fingerlings during 60-days sub-lethal copper (Cu). After acclimation period to two weeks, for determine the LC50/96 h value, total of 27 aquarium with a capacity of 60 L each stocked with 10 fishes an aquarium. Tunney four aquarium and 8 concentrations of (Cu) composed the 24 treatments while 3 other aquaria were used as control. For each treatment, three replications were conducted. And experiment to determine the growth performance fish were transferred into fiberglass aquaria of 200 L water capacity for growth trials. The treated fish were kept in the aquarium containing sub-lethal concentrations of Cu (0.11 and 0.23 mg L(-1)) and affected to grow for 60 days, while control fish were placed in metal free water. The results indicated that median lethal concentrations (LC50) of copper to Caspian Sea kutum for 96 h exposure was 2.310 ppm. The chronic sub-lethal water-borne Cu exposure to the fish exerted that fish had significantly decreased final body weight in comparison to control group. The copper sulfate also had significant negative effects on specific growth rate (SGR) and feed conversion efficiency (FCE) in comparison to those fed the control group. The feed conversion ratio (FCR) and condition factor (CF) were significantly increased in comparison with the control group (P < 0.05). Also survival rate in experimental treatments in comparison with control group, was significantly decreased (P < 0.05). The treated fish exhibited significantly lower body weight and length gains than that of control. The increments of fish weights, fork and total lengths, condition factor, feed intake and condition factor of treated and control fish varied significantly during study period. Hence, concluded that copper sulfate is toxic for Caspian sea kutum (Rutilus frisii kutum).