Table 1.

Morphometric parameters of the gills, and ionoregulatory status of plasma ion concentrations of the scaleless carp in normoxic and hypoxic water

		Hypoxia				Recovery after hypoxia
	Normoxia	4 h	8 h	12 h	24 h	6 h	12 h
Gill morphology (μm)
Protruding lamellar height	78.9±1.7	80.2±1.8	89.1±1.4^*	100.6±2.2^*	107.2±1.6^*	102.3±2.0^*	92.4±2.3^*
Protruding lamellar basal length	350.8±6.7	356.5±9.0	368.8±9.3^*	389.0±10.5^*	412.3±11.6^*	388.4±7.1^*	364.7±8.5^*
Lamellar thickness	11.8±0.5	11.8±0.9	10.6±0.6^*	9.1±0.3^*	8.4±0.4^*	10.6±0.8^*	11.2±0.4^*
Number of nuclei in interlamellar cell mass	17.5±0.6	–	–	12.7±0.5^*	10.4±0.2^*	10.9±0.4^*	12.2±0.3^*
Plasma ion levels (mmol l^–1)
Ca²⁺	3.8±0.1	4.0±0.2	3.7±0.2	3.9±0.2	3.6±0.2	3.8±0.2	3.1±0.1^*
Mg²⁺	0.8±0.0	1.2±0.1^*	1.0±0.0^*	1.0±0.0	0.9±0.0	0.7±0.0	0.8±0.0
K⁺	2.1±0.2	2.9±0.2	3.0±0.4	3.9±0.3^*	3.4±0.6^*	3.4±0.4^*	3.2±0.2

Values are means ± s.e.m. ^*Significantly different (P<0.05) from respective normoxic value