Effects of Digestible Crude Protein and Lipid Levels on Growth Performance, Metabolism of Energy Substances and Antioxidant Capacity of Juvenile GIFI Tilapia, Oreochromis niloticus

doi:10.11924/j.issn.1000-6850.casb2020-0335

Abstract

Abstract:

This experiment was conducted to evaluate the effects of digestible crude protein (DCP) and lipid (DL) levels on growth performance, metabolism of energy substances and antioxidant capacity of juvenile GIFI Tilapia (Oreochromis niloticus), and thereby to determine the optimal rate of digestible crude protein to digestible energy (DCP/DE). Juvenile fish with an initial average body weight of 2 g were fed 12 experimental diets with different nitrogen to energy ratios prepared with different DCP levels (22%, 24%, 26%, 28%) and DL levels (3%, 5%, 7%) for 10 weeks. The results showed as follows: with the increasing level of DCP and DL, the body weight gain (WG) and specific growth rate (SGR) of fish were significantly increased, but there was no significant difference between the 5%DL and the 7%DL group, and the protein efficiency showed a gradually decreasing trend. The WG and SGR of fish in the DCP26DL5 group were not significantly different from those in the highest DCP26DL7 group. The pepsin activity in DCP26DL5 group was significantly higher than that in DCP28DL3 group. The serum AST activity in DCP26DL5 group was the lowest. The TC and LDL-C content in DCP26DL5 group were significantly lower than those in DCP22DL7 group, and there was no significant change in blood glucose level among all groups. The antioxidant function of fish body was significantly increased. The SOD activity in liver of DCP26DL5 group was significantly higher than that in DCP22DL3 group. Findings reveal that high dietary DCP level will reduce protein efficiency, and high DL level will cause plateauing period of growth performance. The suitable level of DCP for juvenile tilapia is 26%, and the level of lipid is 5%. The optimal DCP/DE is 19.18 mg/KJ.

Key words: Oreochromis niloticus, digestible crude protein, lipid, growth, metabolism of energy substances, antioxidant capacity

CLC Number:

S963.71

Li Guangbin, Li Ying, Wang Qiumei, Zhang Xindang, Lin Beibei, Chen Lusi, Deng Junming. Effects of Digestible Crude Protein and Lipid Levels on Growth Performance, Metabolism of Energy Substances and Antioxidant Capacity of Juvenile GIFI Tilapia, Oreochromis niloticus[J]. Chinese Agricultural Science Bulletin, 2021, 37(20): 126-135.

Figures/Tables 6

References 27

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原料/%		DCP22			DCP24			DCP26			DCP28
原料/%		DL3	DL5	DL7	DL3	DL5	DL7	DL3	DL5	DL7	DL3	DL5	DL7
进口鱼粉		4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50
菜籽粕		8.00	8.00	8.00	10.00	10.00	10.00	12.10	12.10	12.10	14.00	14.00	14.00
豆粕		16.80	16.80	16.80	19.40	19.40	19.40	22.50	22.50	22.50	25.50	25.50	25.50
棉籽粕		5.00	5.00	5.00	7.00	7.00	7.00	9.00	9.00	9.00	11.00	11.00	11.00
面粉		24.40	24.40	24.40	21.80	21.80	21.80	17.00	17.00	17.00	16.00	16.00	16.00
小麦麸		23.50	23.50	23.50	21.00	21.00	21.00	18.70	18.70	18.70	14.00	14.00	14.00
豆油		0.50	2.50	4.50	0.50	2.50	4.50	0.50	2.50	4.50	0.50	2.50	4.50
大豆卵磷脂		0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50
α-淀粉		5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50
微晶纤维素		8.00	6.00	4.00	6.50	4.50	2.50	6.40	4.40	2.40	5.20	3.20	1.20
磷酸二氢钙		0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80
氯化胆碱		0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30
食盐		0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20
三氧化二铬		1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00
矿物质预混料^（1）		0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50
维生素预混料^（2）		0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50
营养水平/%	干物质	87.78	86.12	86.94	85.87	87.55	87.97	87.58	88.11	87.96	88.02	87.72	87.98
	粗蛋白	26.16	25.91	26.07	28.00	27.85	28.13	30.04	30.11	30.08	32.28	32.37	31.85
	粗脂肪	3.69	5.74	7.68	3.56	5.44	7.42	3.44	5.29	7.33	3.39	5.66	7.46
	粗灰分	6.14	5.98	6.13	6.26	6.24	6.44	6.45	6.51	6.63	6.61	6.79	6.65
	总磷	0.66	0.66	0.61	0.60	0.61	0.66	0.62	0.68	0.71	0.61	0.66	0.65
	能量	18.79	19.18	19.38	18.77	19.28	19.52	19.03	19.29	19.53	18.86	19.36	19.52
	可消化粗蛋白DCP/%	23.40	23.72	23.92	24.56	25.01	25.22	26.59	26.85	26.67	29.50	29.17	28.79
	可消化能DE/(KJ/g)	12.35	14.58	15.03	13.05	13.85	14.38	12.73	14.00	14.57	14.15	13.80	14.19
	DCP/DE/(mg/KJ)	18.95	16.26	15.92	18.82	18.06	17.54	20.89	19.18	18.30	20.84	21.14	20.28

原料/%		DCP22			DCP24			DCP26			DCP28
原料/%		DL3	DL5	DL7	DL3	DL5	DL7	DL3	DL5	DL7	DL3	DL5	DL7
进口鱼粉		4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50	4.50
菜籽粕		8.00	8.00	8.00	10.00	10.00	10.00	12.10	12.10	12.10	14.00	14.00	14.00
豆粕		16.80	16.80	16.80	19.40	19.40	19.40	22.50	22.50	22.50	25.50	25.50	25.50
棉籽粕		5.00	5.00	5.00	7.00	7.00	7.00	9.00	9.00	9.00	11.00	11.00	11.00
面粉		24.40	24.40	24.40	21.80	21.80	21.80	17.00	17.00	17.00	16.00	16.00	16.00
小麦麸		23.50	23.50	23.50	21.00	21.00	21.00	18.70	18.70	18.70	14.00	14.00	14.00
豆油		0.50	2.50	4.50	0.50	2.50	4.50	0.50	2.50	4.50	0.50	2.50	4.50
大豆卵磷脂		0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50
α-淀粉		5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50	5.50
微晶纤维素		8.00	6.00	4.00	6.50	4.50	2.50	6.40	4.40	2.40	5.20	3.20	1.20
磷酸二氢钙		0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80	0.80
氯化胆碱		0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30	0.30
食盐		0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20	0.20
三氧化二铬		1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00
矿物质预混料^（1）		0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50
维生素预混料^（2）		0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50	0.50
营养水平/%	干物质	87.78	86.12	86.94	85.87	87.55	87.97	87.58	88.11	87.96	88.02	87.72	87.98
	粗蛋白	26.16	25.91	26.07	28.00	27.85	28.13	30.04	30.11	30.08	32.28	32.37	31.85
	粗脂肪	3.69	5.74	7.68	3.56	5.44	7.42	3.44	5.29	7.33	3.39	5.66	7.46
	粗灰分	6.14	5.98	6.13	6.26	6.24	6.44	6.45	6.51	6.63	6.61	6.79	6.65
	总磷	0.66	0.66	0.61	0.60	0.61	0.66	0.62	0.68	0.71	0.61	0.66	0.65
	能量	18.79	19.18	19.38	18.77	19.28	19.52	19.03	19.29	19.53	18.86	19.36	19.52
	可消化粗蛋白DCP/%	23.40	23.72	23.92	24.56	25.01	25.22	26.59	26.85	26.67	29.50	29.17	28.79
	可消化能DE/(KJ/g)	12.35	14.58	15.03	13.05	13.85	14.38	12.73	14.00	14.57	14.15	13.80	14.19
	DCP/DE/(mg/KJ)	18.95	16.26	15.92	18.82	18.06	17.54	20.89	19.18	18.30	20.84	21.14	20.28

处理组		FBW/(g/尾)	FR/[g/(kg·d)]	SR/%	WG	SGR/%	PER/%	PDR/%	FCR/%
DCP22	DL3	35.86 ± 1.72^b	0.90 ± 0.05^a	100.00 ± 0.00	26.85 ± 1.51^a	4.56 ± 0.08^b	2.62 ± 0.05^cde	137.26 ± 3.13^bcd	1.67 ± 0.04^a
	DL5	40.49 ± 3.33^bc	1.05 ± 0.04^bc	98.89 ± 1.11	31.36 ± 1.33^b	4.73 ± 0.14^bc	2.62 ± 0.34^bcde	132.82 ± 16.08^bcd	1.76 ± 0.20^a
	DL7	47.36 ± 3.06^cd	1.13 ± 0.05^bc	100.00 ± 0.00	34.23 ± 1.69^b	5.00 ± 0.10^cd	2.82 ± 0.21^e	137.70 ± 7.39^bcd	1.58 ± 0.13^a
DCP24	DL3	45.60 ± 2.77^cd	1.03 ± 0.01^b	100.00 ± 0.00	31.24 ± 0.33^b	4.94 ± 0.10^cd	2.79 ± 0.19^de	154.49 ± 10.64^d	1.51 ± 0.11^a
	DL5	46.53 ± 2.46^cd	1.09 ± 0.03^bc	100.00 ± 0.00	33.10 ± 0.88^b	4.98 ± 0.09^cd	2.67 ± 0.17^cde	144.78 ± 9.06^cd	1.55 ± 0.11^a
	DL7	40.36 ± 1.96^bc	1.07 ± 0.02^bc	97.78 ± 2.22	31.60 ± 1.00^b	4.71 ± 0.12^bc	2.29 ± 0.14^bcd	118.85 ± 6.20^ab	1.78 ± 0.11^a
DCP26	DL3	28.76 ± 2.20^a	0.89 ± 0.02^a	96.67 ± 1.93	25.84 ± 0.44^a	4.15 ± 0.09^a	1.81 ± 0.13^a	99.86 ± 6.69^a	2.12 ± 0.16^b
	DL5	47.97 ± 2.00^cd	1.10 ± 0.07^bc	97.78 ± 1.11	32.51 ± 2.26^b	4.99 ± 0.08^cd	2.51 ± 0.06^bcde	138.62 ± 4.32^bcd	1.50 ± 0.04^a
	DL7	50.37 ± 0.66^d	1.17 ± 0.03^c	97.78 ± 2.22	34.70 ± 1.41^b	5.07 ± 0.05^d	2.48 ± 0.02^bcde	134.17 ± 1.20^bcd	1.52 ± 0.01^a
DCP28	DL3	46.93 ± 2.46^cd	1.10 ± 0.04^bc	100.00 ± 0.00	33.47 ± 1.17^b	4.99 ± 0.08^cd	2.27 ± 0.05^abc	131.89 ± 1.83^bcd	1.55 ± 0.03^a
	DL5	44.33 ± 0.54^cd	1.13 ± 0.02^bc	100.00 ± 0.00	34.11 ± 0.44^b	4.90 ± 0.02^cd	2.10 ± 0.05^ab	117.81 ± 2.16^ab	1.68 ± 0.04^a
	DL7	48.11 ± 1.61^d	1.09 ± 0.02^bc	100.00 ± 0.00	33.20 ± 0.74^b	5.03 ± 0.06^d	2.38 ± 0.05^bcde	127.15 ± 3.70^bc	1.50 ± 0.03^a
可消化粗蛋白质水平/%
22		41.24 ± 2.18^a	0.60 ± 0.04	99.63 ± 0.37	30.82 ± 1.31^a	4.76 ± 0.08^a	2.69 ± 0.12^b	135.92 ± 5.25	1.67 ± 0.07
24		44.16 ± 1.54^a	0.61 ± 0.01	99.26 ± 0.74	31.98 ± 0.49^ab	4.88 ± 0.07^ab	2.58 ± 0.11^b	139.37 ± 6.91	1.61 ± 0.07
26		42.37 ± 3.53^ab	0.60 ± 0.05	97.41 ± 0.93	31.01 ± 1.54^a	4.74 ± 0.15^a	2.27 ± 0.12^a	124.21 ± 6.55	1.71 ± 0.11
28		46.46 ± 1.03^b	0.62 ± 0.01	100.00 ± 0.00	33.59 ± 0.44^b	4.97 ± 0.03^b	2.25 ± 0.05^a	125.62 ± 2.47	1.58 ± 0.03
脂肪水平/%
3		39.29 ± 2.45^a	0.58 ± 0.03	99.17 ± 0.60	29.35 ± 1.03^a	4.66 ± 0.11^a	2.37 ± 0.12	130.87 ± 6.58	1.71 ± 0.08
5		44.83 ± 1.30^b	0.62 ± 0.02	99.17 ± 0.43	32.77 ± 0.67^b	4.90 ± 0.05^b	2.48 ± 0.11	133.51 ± 5.06	1.62 ± 0.05
7		46.55 ± 1.42^b	0.62 ± 0.02	98.89 ± 0.75	33.43 ± 0.65^b	4.95 ± 0.06^b	2.50 ± 0.08	129.47 ± 3.11	1.59 ± 0.06
Two-way ANOVA
DCP		0.043	0.681	0.052	0.042	0.011	0.002	0.077	0.376
DL		<0.001	0.090	0.926	<0.001	<0.001	0.473	0.764	0.246
DCP×DL		<0.001	0.659	0.735	0.009	<0.001	0.013	0.002	0.003

处理组		FBW/(g/尾)	FR/[g/(kg·d)]	SR/%	WG	SGR/%	PER/%	PDR/%	FCR/%
DCP22	DL3	35.86 ± 1.72^b	0.90 ± 0.05^a	100.00 ± 0.00	26.85 ± 1.51^a	4.56 ± 0.08^b	2.62 ± 0.05^cde	137.26 ± 3.13^bcd	1.67 ± 0.04^a
	DL5	40.49 ± 3.33^bc	1.05 ± 0.04^bc	98.89 ± 1.11	31.36 ± 1.33^b	4.73 ± 0.14^bc	2.62 ± 0.34^bcde	132.82 ± 16.08^bcd	1.76 ± 0.20^a
	DL7	47.36 ± 3.06^cd	1.13 ± 0.05^bc	100.00 ± 0.00	34.23 ± 1.69^b	5.00 ± 0.10^cd	2.82 ± 0.21^e	137.70 ± 7.39^bcd	1.58 ± 0.13^a
DCP24	DL3	45.60 ± 2.77^cd	1.03 ± 0.01^b	100.00 ± 0.00	31.24 ± 0.33^b	4.94 ± 0.10^cd	2.79 ± 0.19^de	154.49 ± 10.64^d	1.51 ± 0.11^a
	DL5	46.53 ± 2.46^cd	1.09 ± 0.03^bc	100.00 ± 0.00	33.10 ± 0.88^b	4.98 ± 0.09^cd	2.67 ± 0.17^cde	144.78 ± 9.06^cd	1.55 ± 0.11^a
	DL7	40.36 ± 1.96^bc	1.07 ± 0.02^bc	97.78 ± 2.22	31.60 ± 1.00^b	4.71 ± 0.12^bc	2.29 ± 0.14^bcd	118.85 ± 6.20^ab	1.78 ± 0.11^a
DCP26	DL3	28.76 ± 2.20^a	0.89 ± 0.02^a	96.67 ± 1.93	25.84 ± 0.44^a	4.15 ± 0.09^a	1.81 ± 0.13^a	99.86 ± 6.69^a	2.12 ± 0.16^b
	DL5	47.97 ± 2.00^cd	1.10 ± 0.07^bc	97.78 ± 1.11	32.51 ± 2.26^b	4.99 ± 0.08^cd	2.51 ± 0.06^bcde	138.62 ± 4.32^bcd	1.50 ± 0.04^a
	DL7	50.37 ± 0.66^d	1.17 ± 0.03^c	97.78 ± 2.22	34.70 ± 1.41^b	5.07 ± 0.05^d	2.48 ± 0.02^bcde	134.17 ± 1.20^bcd	1.52 ± 0.01^a
DCP28	DL3	46.93 ± 2.46^cd	1.10 ± 0.04^bc	100.00 ± 0.00	33.47 ± 1.17^b	4.99 ± 0.08^cd	2.27 ± 0.05^abc	131.89 ± 1.83^bcd	1.55 ± 0.03^a
	DL5	44.33 ± 0.54^cd	1.13 ± 0.02^bc	100.00 ± 0.00	34.11 ± 0.44^b	4.90 ± 0.02^cd	2.10 ± 0.05^ab	117.81 ± 2.16^ab	1.68 ± 0.04^a
	DL7	48.11 ± 1.61^d	1.09 ± 0.02^bc	100.00 ± 0.00	33.20 ± 0.74^b	5.03 ± 0.06^d	2.38 ± 0.05^bcde	127.15 ± 3.70^bc	1.50 ± 0.03^a
可消化粗蛋白质水平/%
22		41.24 ± 2.18^a	0.60 ± 0.04	99.63 ± 0.37	30.82 ± 1.31^a	4.76 ± 0.08^a	2.69 ± 0.12^b	135.92 ± 5.25	1.67 ± 0.07
24		44.16 ± 1.54^a	0.61 ± 0.01	99.26 ± 0.74	31.98 ± 0.49^ab	4.88 ± 0.07^ab	2.58 ± 0.11^b	139.37 ± 6.91	1.61 ± 0.07
26		42.37 ± 3.53^ab	0.60 ± 0.05	97.41 ± 0.93	31.01 ± 1.54^a	4.74 ± 0.15^a	2.27 ± 0.12^a	124.21 ± 6.55	1.71 ± 0.11
28		46.46 ± 1.03^b	0.62 ± 0.01	100.00 ± 0.00	33.59 ± 0.44^b	4.97 ± 0.03^b	2.25 ± 0.05^a	125.62 ± 2.47	1.58 ± 0.03
脂肪水平/%
3		39.29 ± 2.45^a	0.58 ± 0.03	99.17 ± 0.60	29.35 ± 1.03^a	4.66 ± 0.11^a	2.37 ± 0.12	130.87 ± 6.58	1.71 ± 0.08
5		44.83 ± 1.30^b	0.62 ± 0.02	99.17 ± 0.43	32.77 ± 0.67^b	4.90 ± 0.05^b	2.48 ± 0.11	133.51 ± 5.06	1.62 ± 0.05
7		46.55 ± 1.42^b	0.62 ± 0.02	98.89 ± 0.75	33.43 ± 0.65^b	4.95 ± 0.06^b	2.50 ± 0.08	129.47 ± 3.11	1.59 ± 0.06
Two-way ANOVA
DCP		0.043	0.681	0.052	0.042	0.011	0.002	0.077	0.376
DL		<0.001	0.090	0.926	<0.001	<0.001	0.473	0.764	0.246
DCP×DL		<0.001	0.659	0.735	0.009	<0.001	0.013	0.002	0.003

处理组		肠道AMS/(U/mg prot)	肝脏AMS/(U/mg prot)	肠道LPS/(U/g prot)	肝脏LPS/(U/g prot)	肠道胰蛋白/(U/g prot)	胃蛋白酶/(U/mg prot)
DCP22	DL3	1.28 ± 0.17^abc	0.93 ± 0.11^abc	45.57 ± 2.96^a	33.43 ± 8.39^c	5.04 ± 0.44^abc	13.33 ± 0.65^b
	DL5	1.11 ± 0.02^a	0.69 ± 0.13^a	47.74 ± 8.04^ab	19.95 ± 5.36^abc	4.70 ± 0.10^abc	11.92 ± 1.03^b
	DL7	1.07 ± 0.06^a	1.02 ± 0.010^abc	42.35 ± 12.16^ab	23.48 ± 5.64^abc	4.36 ± 0.48^ab	12.15 ± 1.12^b
DCP24	DL3	1.11 ± 0.10^a	0.91 ± 0.03^abc	61.30 ± 11.06^ab	8.16 ± 2.25^a	9.44 ± 0.93^d	8.83 ± 1.11^ab
	DL5	1.04 ± 0.07^a	0.74 ± 0.07^a	33.84 ± 6.51^ab	15.60 ± 5.69^ab	6.72 ± 0.38^bc	12.87 ± 0.93^b
	DL7	1.16 ± 0.19^ab	0.95 ± 0.08^abc	33.16 ± 8.57^ab	24.44 ± 5.59^abc	7.38 ± 0.74^cd	12.99 ± 0.61^b
DCP26	DL3	1.11 ± 0.05^a	0.82 ± 0.03^ab	36.49 ± 4.97^ab	24.20 ± 0.96^abc	9.34 ± 0.48^d	12.06 ± 0.63^b
	DL5	1.15 ± 0.09^ab	0.97 ± 0.11^abc	27.65 ± 0.56^ab	29.95 ± 6.06^bc	5.82 ± 1.41^bc	13.19 ± 3.57^b
	DL7	1.09 ± 0.05^a	1.15 ± 0.08^bc	52.28 ± 14.13^abc	12.56 ± 3.45^a	7.63 ± 1.43^cd	11.96 ± 1.85^b
DCP28	DL3	1.52 ± 0.13^bc	1.22 ± 0.21^c	44.16 ± 3.52^abc	31.20 ± 5.32^bc	4.92 ± 1.24^abc	7.10 ± 1.14^a
	DL5	1.64 ± 0.14^c	0.93 ± 0.13^abc	45.84 ± 15.04^bc	25.00 ± 4.51^abc	5.38 ± 1.17^bc	9.24 ± 1.21^ab
	DL7	1.27 ± 0.20^abc	1.19 ± 0.14^c	78.16 ± 14.69^c	31.01 ± 4.74^bc	2.27 ± 0.73^a	9.73 ± 0.29^ab
可消化粗蛋白质水平/%
22		1.16 ± 0.06^a	0.88 ± 0.07^a	45.22 ± 4.36	25.62 ± 3.87^ab	4.70 ± 0.21^a	12.47 ± 0.52^b
24		1.11 ± 0.07^a	0.87 ± 0.05^a	42.77 ± 6.43	16.07 ± 3.36^a	7.85 ± 0.55^b	11.56 ± 0.82^b
26		1.12 ± 0.03^a	0.98 ± 0.06^ab	38.81 ± 5.63	22.24 ± 3.27^ab	7.59 ± 0.78^b	12.40 ± 1.19^b
28		1.47 ± 0.10^b	1.11 ± 0.09^b	56.05 ± 8.27	29.07 ± 2.64^b	4.19 ± 0.72^a	8.69 ± 0.63^a
脂肪水平/%
3		1.26 ± 0.07	0.97 ± 0.07^ab	46.88 ± 3.88	24.25 ± 3.69	7.19 ± 0.76	10.33 ± 0.84
5		1.24 ± 0.08	0.83 ± 0.06^a	38.77 ± 4.64	22.63 ± 2.83	5.65 ± 0.46	11.81 ± 0.98
7		1.15 ± 0.07	1.08 ± 0.05^b	51.49 ± 7.39	22.87 ± 2.90	5.41 ± 0.78	11.71 ± 0.60
Two-way ANOVA
DCP		0.003	0.034	0.189	0.032	<0.001	0.011
DL		0.405	0.014	0.195	0.892	0.021	0.284
DCP×DL		0.521	0.473	0.080	0.048	0.142	0.476