title: [Effect of locomotion and feeding on metabolic mode of juvenile lenok, Brachymystax lenok (Pallas) under different water temperatures].
abstract: To investigate the effect of locomotion and feeding on the metabolic mode of juvenile lenok, Brachymystax lenok (Pallas) under different water temperatures, the pre-exercise oxygen consumption rate (MO2p), active oxygen consumption rate (MO2a), metabolic scope (MS), critical swimming speed (Uc) and swimming metabolic rate of both fasting and fed fish were measured at five temperature levels (4 degrees C, 8 degrees C, 12 degrees C, 16 degrees C and 20 degrees C) and ten flow velocities with saturated dissolved oxygen (> 8.0 mg x L(-1)). The results showed that the MO2p and MO2a of the feeding group were significantly higher (P < 0.05) than the fasting group under different temperatures, and the increases in MO2p and MO2a at 4 degrees C, 8 degrees C, 12 degrees C, 16 degrees C and 20 degrees C were 15%, 47%, 30%, 43% and 8%, and 12%, 23%, 21%, 36% and 7%, respectively. No significant differences were observed for Uc and MS between the fasting and the feeding groups (P > 0.05), but the MS showed a trend of decline with increase in water temperature. Swimming metabolic rate of fish was increased with increasing the flow velocity, and further increase of flow velocity resulted in a decline in swimming metabolic rate, and the swimming metabolic rate of the feeding group was significantly higher than that of the fasting group (P < 0.05). The metabolic rate increased with increasing the swimming speed up to 70% Uc, and then decreased with increasing the swimming speed up to Uc. It was concluded that, under certain temperature, the maximum metabolic rate was induced by exercise and feeding; the metabolic rate exhibited the additive metabolic mode before increasing to the maximum and thereafter, the metabolic rate induced by feeding reduced with decreasing the swimming metabolic rate, exhibiting the locomotion prioritized mode.
authors.forename: Ge-Feng
authors.initials: GF
authors.lastname: Xu
authors.forename: Yu-Yu
authors.initials: YY
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.forename: Bo
authors.initials: B
authors.lastname: Ma
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Zhen-Bo
authors.initials: ZB
authors.lastname: Mou
mesh_terms: D000818:Animals; D010101:Oxygen Consumption; D012487:Salmonidae / Q000378:metabolism* / Q000502:physiology; D013550:Swimming; D013696:Temperature; D014867:Water
chemical_list: D014867:Water