Tryptophan supplementation helps totoaba (Totoaba macdonaldi) juveniles to regain homeostasis in high-density culture conditions

Effect of dietary tryptophan on blood and plasma parameters of striped bass Morone saxatilis, exposed to acute stressors

“…TP was from 2.09 to 2.84 g dL -1 , lower than that reported by Tisa & Strange (1983), but similar to that reported by Alvarez-Mendoza et al (2013) in the undisturbed group and Del Río-Zaragoza et al ( 2021). Likewise, these values are similar to those reported in T. macdonaldi (Cabanillas-Gámez et al 2020). The values are within a lower limit than those reported in Acipenser brevirostrum by Knowles et al (2006) and Sparus aurata by Peres et al (2013) and lower than the range reported in Dicentrarchus labrax by Peres et al (2014), which suggests that the TP level could depend on the fish species, size, and condition.…”

“…The D1.0 and D1.5 diets decreased TP in the undisturbed group, which could have been related to higher energy expenditure. As reported earlier, these dietary Trp levels induce an increase in cortisol and a reduction in GLU in T. macdonaldi (Cabanillas-Gámez et al 2020). Stress triggers the synthesis, release, and turnover of glutamate, neuromodulators, and neuropeptides, metabolically expensive processes (Nonogaki 2000).…”

“…Furthermore, after fish were exposed to the stress factors, those fed with higher dietary Trp showed lower GLU levels than those fed with a CD0.5 diet. Cabanillas-Gámez et al (2018) reported that 1.55% of dietary Trp prevented the increase in GLU in T. macdonaldi exposed to the same acute stress factors (Cabanillas-Gámez et al 2018), while 0.99 and 1.55% of dietary Trp reduced GLU in T. macdonaldi exposed to chronic stress by high and low density (Cabanillas-Gámez et al 2020). These data revealed that, in general, GLU of striped bass decreased as dietary Trp increased, suggesting that Trp supplemented diets can increase stress resistance of this species under hypoxic conditions or handling.…”

“…To our knowledge, this research reports for the first time the changes in blood and plasma parameters of M. saxatilis juveniles in response to acute hypoxia and handling stressors after one week of feeding with different levels of dietary Trp. The essential amino acid Trp has been shown to reduce responses of several farmed species to several stressors, such as temperature (Kumar et al 2014, Tejpal et al 2014, salinity (Akhtar et al 2013), confinement (Basic et al 2013), nitrite (Ciji et al 2015), copper (Hoseini et al 2012), crowding (Lepage et al 2002, Tejpal et al 2009, handling and hypoxia (Cabanillas-Gámez et al 2018 and high density (Cabanillas-Gámez et al 2020). This research investigates supplementation of Trp to minimize alteration of blood and plasma parameters of M. saxatilis juveniles under acute stress due to hypoxia and handling.…”

Stress management in aquaculture: a review of dietary interventions

“…Melatonin is demonstrated to modulate antioxidant capacity (Maitra & Hasan 2016), immune functions (Cuesta et al 2007(Cuesta et al , 2008 and thereby stress tolerance (Lopez-Patino et al 2013) through an attenuated glucocorticoid response as suggested by several authors (Azpeleta et al 2010;Lopez-Patino et al 2013;Conde-Sieira et al 2014;Gesto et al 2016). Supplementation of dietary tryptophan was demonstrated to enhance stress tolerance of several fish (Lepage et al 2002;Tejpal et al 2009;Hoseini & Hosseini 2010;Hoseini et al 2012Hoseini et al , 2020aAkhtar et al 2013a,b,c;Basic et al 2013;Fatahi & Hoseini 2013;Kumar et al 2014a;Ciji et al 2015;Di ogenes et al 2019;Cabanillas-G amez et al 2020;Ciji & Akhtar 2020;Herrera et al 2020). Indeed, dietary tryptophan inclusion reduces aggressive behaviour, cannibalism and confrontations in a number of fish (Hseu et al 2003;H€ oglund et al, 2005;Wolkers et al 2012Wolkers et al , 2014Neto & Giaquinto 2020).…”