The optimal dietary arginine level of laying hens fed with low-protein diets

Table 9 Effect of the dietary arginine level in a low-protein diet on intestinal morphology¹

Item	Control²	Dietary arginine level in LP diet, %³					P-value
Item	Control²	0.80	0.85	0.90	0.95	1.00	Diet⁴	Linear⁵	Quadratic⁵
Duodenum
Villus height, μm	1854 ± 84^a	1612 ± 47^bc	1735 ± 35^ab	1723 ± 26^ab	1577 ± 62^bc	1498 ± 71^c	0.001	0.011	0.003
Crypt depth, μm	275.9 ± 26.0	269.2 ± 18.1	248.7 ± 12.0	304.9 ± 19.8	293.6 ± 9.6	290.7 ± 11.8	0.255	0.069	0.561
Villus height:crypt depth	7.17 ± 0.71^a	6.17 ± 0.42^ab	7.04 ± 0.22^a	5.83 ± 0.40^ab	5.43 ± 0.32^b	5.25 ± 0.39^b	0.011	0.004	0.318
Jejunum
Villus height, μm	1574 ± 74^a	1493 ± 34^ab	1646 ± 43^a	1544 ± 53^ab	1394 ± 65^bc	1313 ± 47^c	0.001	< 0.001	0.004
Crypt depth, μm	225.9 ± 5.0	257.5 ± 24.2	236.0 ± 12.7	247.4 ± 12.8	223.1 ± 13.0	232.2 ± 8.9	0.499	0.166	0.654
Villus height:crypt depth	7.01 ± 0.40^a	6.08 ± 0.47^ab	7.08 ± 0.36^a	6.35 ± 0.37^ab	6.30 ± 0.22^ab	5.69 ± 0.23^b	0.012	0.155	0.048
Ileum
Villus height, μm	1022 ± 48	1012 ± 52	1015 ± 25	965.1 ± 55.1	987.9 ± 26.1	930.3 ± 26.4	0.592	0.156	0.755
Crypt depth, μm	157.3 ± 4.7	192.4 ± 14.4	176.7 ± 6.8	174.4 ± 10.1	159.9 ± 8.0	173.3 ± 10.4	0.140	0.096	0.236
Villus height:crypt depth	6.51 ± 0.29	5.53 ± 0.59	5.80 ± 0.25	5.65 ± 0.39	6.28 ± 0.34	5.51 ± 0.37	0.340	0.729	0.385

¹Data were presented as the mean ± SD (n = 8)
²The control hens were fed a diet with 16% protein level
³The experimental groups were provided a 14% protein diets (0.80% Arginine) supplemented with 0, 0.05%, 0.10%, 0.15%, and 0.20% L-Arg
⁴Diet = effect of all the dietary treatments
⁵Linear and quadratic = effect of dietary arginine from 0.80% to 1.00% treatments
^a-c: Means with different superscripts within the same column differ significantly, P < 0.05

ISSN: 2049-1891