Table 8. Digestive enzyme activities in hepatopancreas of Pacific white shrimp Penaeus vannamei fed the experimental diets for 8 weeks

	Trypsin1)	Chymotrypsin2)	Amylase3)	Lipase4)
Con	5.49 ± 0.50b	3.30 ± 0.19	458.6 ± 47.39b	1.77 ± 0.12c
TB5	5.98 ± 0.90b	3.45 ± 0.29	484.2 ± 12.28b	2.68 ± 0.05b
TB10	7.32 ± 0.34a	3.40 ± 0.07	475.1 ± 13.50b	3.14 ± 0.35ab
TB20	8.15 ± 0.29a	3.66 ± 0.31	551.3 ± 30.36b	3.55 ± 0.30a
Pr > F*
ANOVA	0.000	0.224	0.004	0.000
Linear	0.000	0.074	0.002	0.000
Quadratic	0.550	0.627	0.113	0.056

Values are mean of four replicate groups (n = 4) and presented as mean ± SD.
Values with different superscripts in the same column are significantly different (p < 0.05).
Trypsin activity (BAPNA unit/mg protein).
Chymotrypsin activity (SAPNA units/mg protein).
Amylase activity (mU/mg protein).
Lipase activity (specific activity U).
Con, basal diet; TB, tributyrin; TB5, TB10 and TB20 are 0.05%, 0.1% and 0.2% TB supplemented diet: ANOVA, analysis of variance; BAPNA, benzoyl-DL-arginine-p-nitroanilide; SAPNA, Suc-Ala-Ala-Pro-Phe-p-nitroanilide.
Probability value associated with the F-statistic. Values < 0.05 indicate significant differences among treatments.