Table 1. Effects of carbon dioxide (% CO2) on haematological parameters, pH and oxygen transport-related variables for blood of rainbow trout.
CO 2 (%) | 0.25 | 0.5 | 1 | 2 | 4 | ||||
PCO 2 (mm Hg) | 1.9 | 3.8 | 7.6 | 15.2 | 30.4 | ||||
[Hb] (mM) | 0.9 ±0.0abc | 0.9 ±0.0abc | 1.0 ±0.0b | 1.0 ±0.0b | 0.8 ±0.1c | ||||
Hct (%) | 23.2 ±0.0abd | 22.5 ±0.3b | 25.3 ±0.8c | 26.1 ±0.4c | 24.5 ±0.2cd | ||||
MCHC | 3.7 ±0.2ab | 4.2 ±0.1a | 4.1 ±0.1a | 4.0 ±0.1a | 3.1 ±0.4b | ||||
pH i | 7.40 ±0.00a | 7.24 ±0.05b | 7.12 ±0.03c | 6.96 ±0.05d | 6.79 ±0.02e | ||||
pH e | 8.01 ±0.00a | 7.81 ±0.04b | 7.69 ±0.02c | 7.46 ±0.03d | 6.96 ±0.01e | ||||
P 50 (mm Hg) | 24.8 ±0.3a | 37.7 ±0.3b | 40.6 ±2.2b | 75.0 ±4.8c | >160.0 | ||||
n H | 1.3 ±0.1a | 1.5 ±0.0a | 1.4 ±0.0a | 1.0 ±0.0b | 0.6 ±0.1c | ||||
Φ | -0.91 ±0.18 | -0.67 ±0.04 | -0.87 ±0.06 | -0.77 ±0.05 |
Haemoglobin concentration [Hb], haematocrit (Hct), mean corpuscular haemoglobin concentration (MCHC), intracellular pH (pHi), extracellular or plasma pH (pHe), the Hill coefficient (nH), and the Bohr coefficient (Φ). All data were collected according to Series 1 protocols on rinsed RBCs. Letters that differ within rows indicate statistically significant effects of CO2.