Influence of Dietary Phosphorus on the Growth, Feed Utilization, Proximate Composition, Intestinal Enzymes, and Oxidation Resistance of Sea Cucumber Apostichopus japonicus

Table 1

Formulation and proximate composition of the experimental diets.

Ingredients (% dry basis)	Dietary phosphorus level (%)
	0.24	0.37	0.51	0.62	0.77	0.89
Seaweed powder^1	23.5	23.5	23.5	23.5	23.5	23.5
Fishmeal^2	8	8	8	8	8	8
Shrimp powder^3	3	3	3	3	3	3
Yeast powder^4	0.5	0.5	0.5	0.5	0.5	0.5
Fish oil^5	1	1	1	1	1	1
Carrageenan^6	5	5	5	5	5	5
Microcrystalline cellulose^7	8	7	6	5	4	3
Sodium dihydrogen phosphate^8	0	1	2	3	4	5
Sea mud^9	50	50	50	50	50	50
Vitamin premix^10	1	1	1	1	1	1
Total	100	100	100	100	100	100
Proximate composition (measured value, %)
Crude protein	12.44	12.45	12.63	12.78	12.52	12.66
Crude fat	1.94	1.92	1.98	1.90	1.91	1.92
Ash	56.17	56.03	56.24	56.17	56.26	56.14
Total phosphorus	0.24	0.37	0.51	0.62	0.77	0.89
Energy (kJ/kg)	10.65	10.70	10.72	10.74	10.75	10.78

¹A mixture of Spiraea thunbergii, L. japonica, S. polycystum, and Ulva lactuca was obtained from Rongcheng Haihao Biotechnology Co., Ltd. Crude protein, 19.5%; crude fat, 0.82%; carbohydrate, 47.8%. ²Tongri Food Co., Ltd., Tsingdao, China. Crude protein, 67.3%; crude fat, 8.4%. ³Xingyi Marine Biological Engineering Co., Ltd., Guangdong, China. Crude protein, 58%; crude fat, 14%. ⁴Angel yeast limited by Share Ltd., Hubei, China. Crude protein, 53%; crude fat, 3.6%. ⁵Yaheng Biological Technology Co. Ltd., Shandong, China. Purity, 99%. ⁶Linghu Xinwang Chemical Co., Ltd., Zhejiang, China. Carbohydrate, 97.8%. ⁷Weifang Haizhiyuan Chemical Co., Ltd., Shandong, China. Purity, 94%. ⁸Shijiazhuang Spring Letter Biological Technology Co., Ltd., Hebei, China. Purity, 99%. ⁹Collected from cage culture area in Changdao sea area (Penglai, China), phosphorus content, 0.018%. ¹⁰Vitamin premix(mg/kg): retinol acetate, 38.0; cholecalciferol, 13.2; a-tocopherol, 210.0; thiamin, 115.0; riboflavin, 380.0; pyridoxine, 88.0; pantothenic acid, 368.0; niacin acid, 1030.0; biotin, 10.0; folic acid, 20.0; vitamin B₁₂, 1.3; inositol, 4000.0; ascorbic acid, 500.0.