Poststress levels of lysozyme and cortisol in adult rainbow trout: heritabilities and genetic correlations

Abstract

Lysozyme response in stressed rainbow trout was compared with measurements of poststress cortisol activity. Estimates of heritability of lysozyme and cortisol were both moderate-to-high and both traits displayed positive genetic correlations in pair-wise comparisons of stress exposures. Genetic correlations between lysozyme and cortisol in stressed rainbow trout tended to be negative, although insignificant. Neither lysozyme, nor cortisol exhibited significant correlations with serum haemolytic activity. It is concluded that the data do not confirm earlier suggestions that lysozyme should be superior to cortisol in consistency of stress response in rainbow trout. 1999 The Fisheries Society of the British Isles

Effects of anthraquinone extract from Rheum officinale Bail on the growth performance and physiological responses of Macrobrachium rosenbergii under high temperature stress

“…Lysozyme is the important part of haemolymph enzyme system in the crustacean [39,40]. Stress would cause the increase of haemolymph lysozyme [41,42] or the decrease of haemolymph lysozyme activity [8,43,44]. The red sea bream (Pagrus major) fed with Chinese herbs [45] and common carp (C. carpio jian) fed with anthraquinone extract [20] showed the increase of blood lysozyme activities under the stress.…”

Anaesthesia of farmed fish: implications for welfare

“…The physiological stress response in fish is similar to that described in other vertebrates and is characterised by three phases (see Wendelaar Bonga 1997, for details). Large species differences in the magnitude of the cortisol response to stress have been found (Barton 2002;Barton and Iwama 1991), and high and low responders within species have also been identified (Fevolden et al 1999;Mommsen et al 1999;Pottinger and Carrick 1999;Pottinger et al 1992Pottinger et al , 1994Sumpter et al 1986;Tanck et al 2001;Trenzado et al 2003).…”

Effects of emodin and vitamin C on growth performance, biochemical parameters and two HSP70s mRNA expression of Wuchang bream (Megalobrama amblycephala Yih) under high temperature stress

“…Lysozyme is one of the important non-specific immune factors of fish, arising from neutrophils and macrophages, and secreted into blood and mucus to play a bacteriolytic effect [40]. It is generally believed that acute stress will cause fish to increase the level of blood lysozyme [3,40e42] while chronic stress may lead lysozyme activity to decrease [2,43]. These trends may be affected by a number of factors, such as stress type, intensity and time [44].…”

“…These trends may be affected by a number of factors, such as stress type, intensity and time [44]. Thus, some researchers believe that the variation of the blood lysozyme activity can be a stress signal in fish [42,45], but its genetic stability is less than that of the cortisol response [43]. Alkaline phosphatase (ALP) is an important metabolic regulation of enzyme in vivo and directly involved in the transfer of phosphate groups and metabolism of calcium and phosphate.…”

“…It is speculated that fish may identify the short-term heat stress as acute stress, and secrete a large amount of cortisol to promote glucose synthesis [46,47] and fat degradation [48,49] so as to gain energy, and to increase specific proteins such as lysozyme or complement to enhance the immunity level [3,39e41], to cope with stress. As the time of heat stress extends, cortisol level will have prolonged elevation, resulting in decreased lysozyme activity and immunity [2,43], and increased susceptibility to pathogens [44].…”