Thermal sensitivity of growth, food intake and activity of juvenile brown trout (original) (raw)

Assessment of Water Temperature on Growth Performance and Protein Profile of Rainbow trout Oncorhynchus my kiss (Walbaum, 1792)

2021

Thermoregulation in poikilothermic animals is influenced by thermal variations. It is known that fish ectotherms are highly influenced by thermal variability during development, which leads to important modifications at several metabolic levels such as growth and its physiology. Thus, the aim of this study was to investigate the effect of varied water temperature on growth performance and protein profiles of rainbow trout Oncorhynchus my kiss [1]. Altogether six varied temperatures as T1(8-10 o C), T2 (10-12 o C), T3 (12-14 o C), T4 (14-16 o C) , T5 (16-18 o C) and T6 (18-20 ° C) were fixed with the help of aquarium heater in 18 aquaria (three replicates) considered as six treatments and normal feeding (45% protein) were done at the rate of 3% of bodyweight twice daily for 90 days. At the end of the feeding trial cent per cent survival rate was recorded in T4 temperature treated group of fish while in other the survival rate was 99.6, 97.3, 96.4, 95.7 and 93.13% respectively. Mean w...

Influences of thermal environment on fish growth

Ecology and evolution, 2017

Thermoregulation in ectothermic animals is influenced by the ability to effectively respond to thermal variations. While it is known that ectotherms are affected by thermal changes, it remains unknown whether physiological and/or metabolic traits are impacted by modifications to the thermal environment. Our research provides key evidence that fish ectotherms are highly influenced by thermal variability during development, which leads to important modifications at several metabolic levels (e.g., growth trajectories, microstructural alterations, muscle injuries, and molecular mechanisms). In Atlantic salmon (Salmo salar), a wide thermal range (ΔT 6.4°C) during development (posthatch larvae to juveniles) was associated with increases in key thermal performance measures for survival and growth trajectory. Other metabolic traits were also significantly influenced, such as size, muscle cellularity, and molecular growth regulators possibly affected by adaptive processes. In contrast, a res...

Microgeographic variation in metabolic rate and energy storage of brown trout: countergradient selection or thermal sensitivity?

We examined the influence of habitat size, growth opportunity, and the thermal conditions experienced during early development on the standard metabolic rate (SMR) of juvenile brown trout (Salmo trutta) from six natural populations to contrast the hypothesis of countergradient selection in metabolic rate. The study populations differed significantly in SMR. Population means for SMR changed in response to the temperature experienced during the yolk-absorption stage, when the risk of oxygen deficit increases and the vulnerability to hypoxia is highest. We also found a strong negative correlation between the temperature experienced during the first 2 months after yolk resorption and SMR, which supports the hypothesis of countergradient variation. Moreover, we detected a strong negative correlation between an index of growth opportunity and relative lipid content, suggesting that the risk of energy shortfall could be a major force in the evolution of storage strategies. Our results suggest that temperature can shape the evolution of metabolic rate during the yolk-absorptive stage or the first feeding stage, while energy storage levels may be more sensitive to thermal constraints acting on growth rates.