Measurements posterior intestine of grasscarp Diameter of the organ(µm) 4291.20±42.10 Thickness of the wall(µm) 1320.35±10.29 Diameter of the lumen(µm) 1650.50±42.37 38.46 % Thickness of mucosa(µm) 925.09 ± 22.63 70.06 % Number of mucosalfolds/ cross section 24.17 ± 4.11 Height of mucosal folds(µm) 902.45±5.22 68.34% Width of mucosal folds(µm) 204.51 ± 10.71 Height of theepithelium (µm) 46.04 ± 0.77 3.48 % Thickness of submucosa(µm) 109.35±5.72 8.28% Thickness of muscularis(µm) 311.72±2.66 23.60%

The values were represented by mean ± standard error.

Table 1: Morphometrical measurements of posterior intestine of grass carp as well as their relation (%) to the wall measurements.