Table 2.

Blood biochemical variables of African catfish exposed with varying levels of salinity and heat stress

	ALT (U/I)	AST (U/I)	Total protein (g/dL)	Albumin (g/dL)	Globulin (g/dL)	Urea (mg/dL)	Creatinine (mg/dL)
Before heat stress
0 ppt	21.98 ± 0.71 c	24.13 ± 0.58 b	4.09 ± 0.02 a	2.18 ± 0.04 a	1.91 ± 0.06 a	2.19 ± 0.04 c	0.32 ± 0.01 b
4 ppt	21.46 ± 0.56 c	23.96 ± 0.30 b	4.07 ± 0.03 a	2.24 ± 0.04 a	1.83 ± 0.06 a	2.21 ± 0.05 c	0.32 ± 0.01 b
8 ppt	24.36 ± 0.65 b	24.94 ± 0.93 b	3.79 ± 0.07 b	2.11 ± 0.02 a	1.68 ± 0.09 b	2.41 ± 0.02 b	0.37 ± 0.01 b
12 ppt	27.25 ± 0.50 a	27.67 ± 0.49 a	3.56 ± 0.07 b	1.92 ± 0.07 b	1.64 ± 0.14 c	2.60 ± 0.08 a	0.41 ± 0.01 a
After heat stress
0 ppt	25.33 ± 0.61 C*	25.96 ± 0.47 C*	3.70 ± 0.04*	2.05 ± 0.04 A*	1.65 ± 0.06 A*	2.30 ± 0.04 C*	0.40 ± 0.01 B*
4 ppt	24.77 ± 0.20 C*	25.75 ± 0.19 C*	3.72 ± 0.03*	2.05 ± 0.01 A*	1.68 ± 0.02 A*	2.41 ± 0.03 C*	0.41 ± 0.01 B*
8 ppt	26.77 ± 0.43 B*	27.14 ± 0.94 B*	3.52 ± 0.05*	1.93 ± 0.04 AB*	1.59 ± 0.08 B*	2.51 ± 0.03 B*	0.43 ± 0.01 B*
12 ppt	29.23 ± 0.52 A*	29.39 ± 0.46 A*	3.33 ± 0.01*	1.81 ± 0.02 B*	1.52 ± 0.02 B*	2.74 ± 0.09 A*	0.48 ± 0.01 A*
Two-way ANOVA (p-value)
Salinity	0.001	0.001	0.001	0.001	0.001	0.001	0.001
Heat stress	0.001	0.001	0.001	0.001	0.001	0.001	0.001
Interaction	0.001	0.001	0.001	0.001	0.001	0.001	0.001

Means ± S.E. in the same column with different small or capital letters differ significantly either before or after the heat stress (p < 0.05). The asterisk (*) refers to significant differences between the same groups before and after heat stress (p < 0.05). AST aspartate aminotransferase ALT alanine aminotransferase