Premium
The Metabolic Costs and Physiological Consequences to Juvenile Rainbow Trout of a Simulated Summer Warming Scenario in the Presence and Absence of Sublethal Ammonia
Author(s) -
Linton Tyler K.,
Reid Scott D.,
Wood Chris M.
Publication year - 1997
Publication title -
transactions of the american fisheries society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.696
H-Index - 86
eISSN - 1548-8659
pISSN - 0002-8487
DOI - 10.1577/1548-8659(1997)126<0259:tmcapc>2.3.co;2
Subject(s) - rainbow trout , bioenergetics , ammonia , zoology , juvenile , fish <actinopterygii> , environmental science , ecology , chemistry , fishery , biology , biochemistry , mitochondrion
Quantitative bioenergetic and physiological measurements were made on juvenile rainbow trout Oncorhynchus mykiss exposed over summer (June–September 1993) to a simulated summer warming scenario of +2°C in the presence and absence of 70 μmol total ammonia/L (nominal; equivalent to 0.013 mg NH 3 ‐N/L at 15°C, pH = 7.6) to determine the metabolic costs and physiological consequences associated with their growth in a warmer, more polluted environment. With unlimited food, fish exposed to +2°C show better energy conversion efficiency and increased nitrogen retention at a metabolic cost equivalent to the base temperature group. Metabolic fuel use appears to have been optimized to support the bioenergetic demands imposed during maximum summer water temperatures. Low‐level ammonia enhances nitrogen and energy conversion efficiency by stimulating protein retention, which ultimately results in the most cost‐effective growth. However, in the +2°C ammonia treatment, the stimulatory effect of low‐level ammonia is lost during mid to late summer due to the greater energy demands when fish are forced to cope with the additional stress of a small further increase in temperature.