In some fishes, clove oil reduced feed intake when
compared with unanaesthetized controls, but this
reduction was similar to that induced by MS222
anaesthesia. Also, repeated anaesthesia using clove oil
had a significant negative effect on growth (Hoskonen
and Pirhonen 2004). However, results of several
studies suggest that the physiology of fish can be
affected by changes in the haematology and biochemistry
of exposed fish. Therefore, it is important to
assess the extent of physiological changes in fish
exposed to an anaesthetic (Park et al. 2008; Carter
et al. 2011).