The Company of Biologists

Table 1.

Plasma Na⁺and Cl^-levels of Arctic char, rainbow trout and Atlantic salmon acclimated to freshwater or seawater for up to 30 days

		Days in freshwater (control)			Days in seawater (32‰)
Species	[Ion] (mEq l^-1)	1	30	1	2	4	10	30
Arctic char	Na⁺	150.3±2.8	152.1±2.5	208.6±7.6^{^*}	231.4±9.3^{^*}	ND	216.7±21.2^{^*}	181.2±13.6^{^*},^{^a}
	Cl^-	137.0±1.9	138.3±2.9	167.5±8.2^{^*}	174.5±7.4^{^*}	ND	168.5±17.0^{^*}	155.2±10.1^{^*},^{^a}
Atlantic salmon	Na⁺	158.0±2.9	153.2±6.2	ND	ND	171.2±6.4^{^*}	156.2±1.5^{^b}	158.9±2.0^{^b}
	Cl^-	134.0±1.7	130.5±3.2	ND	ND	136.9±3.5	124.0±1.9^{^b}	121.1±0.7^{^b}
Rainbow trout	Na⁺	157.4±1.3	159.7±3.5	ND	210.0±12.9^{^*}	218.3±4.6^{^*}	198.6±16.3^{^*}	165.8±5.2^{^a}
	Cl^-	131.4±2.2	136.2±2.8	ND	159.3±5.4^{^*}	172.7±4.9^{^*}	159.5±10.8^{^*}	139.8±4.2^{^a}

		Days in freshwater (control)			Days in seawater (32‰)
Species	[Ion] (mEq l^-1)	1	30	1	2	4	10	30
Arctic char	Na⁺	150.3±2.8	152.1±2.5	208.6±7.6^{^*}	231.4±9.3^{^*}	ND	216.7±21.2^{^*}	181.2±13.6^{^*},^{^a}
	Cl^-	137.0±1.9	138.3±2.9	167.5±8.2^{^*}	174.5±7.4^{^*}	ND	168.5±17.0^{^*}	155.2±10.1^{^*},^{^a}
Atlantic salmon	Na⁺	158.0±2.9	153.2±6.2	ND	ND	171.2±6.4^{^*}	156.2±1.5^{^b}	158.9±2.0^{^b}
	Cl^-	134.0±1.7	130.5±3.2	ND	ND	136.9±3.5	124.0±1.9^{^b}	121.1±0.7^{^b}
Rainbow trout	Na⁺	157.4±1.3	159.7±3.5	ND	210.0±12.9^{^*}	218.3±4.6^{^*}	198.6±16.3^{^*}	165.8±5.2^{^a}
	Cl^-	131.4±2.2	136.2±2.8	ND	159.3±5.4^{^*}	172.7±4.9^{^*}	159.5±10.8^{^*}	139.8±4.2^{^a}

Values are means ± s.e.m.; sample size ranged from 5 to 8, as listed in Results.

ND, not determined (species not sampled on that day).

Interspecies comparisons not included in table, see Results.

Significantly different (P<0.05) from both freshwater control groups.

Significantly different (P<0.05) from all other corresponding seawater groups.

Significantly different (P<0.05) from corresponding 4 day seawater group.