中国水产科学Issue(3)：522-530,9.DOI:10.3724/SP.J.1118.2014.00522
中性植酸酶替代磷酸二氢钙对黑鲷生长和磷利用的影响
Effects of replacing monocalcium phosphate with phytase on growth and phosphorus utilization in black sea bream, Acanthopagrus schlegelii
摘要
Abstract
Because of a decrease in production and increase in the cost of fishmeal, there is increased interest in the use of plant-based feed in aquaculture. However, one of the major problems associated with the use of plant protein in fish feed is the presence of anti-nutritional factors, such as phytate, which is the primary storage form of phosphorus. Phy-tate is essentially unavailable to monogastric or agastric aquatic animals as they lack intestinal phytase that promote phytate hydrolysis during digestion. To address this issue, diets for monogastric or stomachless animals are often sup-plemented with monocalcium phosphate (MCP) to meet their phosphorus requirements. However, MCP is derived from fossils so it is a non-renewable resource. Furthermore, the cost of rock phosphorus has increased dramatically over the past several years. Alternatively, exogenous phytase can be added to hydrolyze phytate, and thus improve the use of phytate phosphorus. Thus, the addition of phytase may lower the need for MCP supplementation, thereby lower feed costs. This strategy may also lower the concentration of phosphorus excreted, resulting in lower eutrophication of the surrounding waters. We evaluated whether neutral phytase could partially replace MCP, and thus reduce the dietary in-clusion of MCP. The fish (initial body weight:11.52 ± 0.12 g) were fed one of four diets for 8 weeks:a control diet (designated P1.5) was prepared with 1.5%MCP but without phytase and three other diets (designated as PP1.5, PP1.0, and PP0.5) were supplemented with 1.5%, 1.0%, or 0.5%MCP, respectively, and 200 mg/kg (diet) phytase. Fish fed PP1.0 and PP0.5 had no significant change in weight gain rate(WGR), specific growth rate (SGR), protein efficiency rate (PER), or feed conversion ratio (FCR) compared with the control (P>0.05), whereas fish fed PP0 had significantly lower growth performance in the above parameters (P>0.05). Phytase addition did not affect body composition. The apparent digestibility coefficients (ADCs) of crude protein and phosphorus increased when fish were fed with the diets in which MCP was replaced by phytase. Additionally, phosphorus discharge was significantly reduced in fish fed diets in which MCP was replaced by phytase. Our results suggest that the dietary phosphorus requirement for meeting normal growth in black sea bream is≥0.51%. MCP can partially be replaced by phytase without affecting the growth of black sea bream. A diet containing 200 mg/kg phytase is equivalent to 1%MCP. The partial substitution of MCP by phytase not only reduces inorganic phosphorus addition to the surrounding waters, but also improves use of phosphorus in the feed.关键词
黑鲷/中性植酸酶/磷酸二氢钙/生长/磷利用率Key words
Acanthopagrus schlegelii/neutral phytase/monocalcium phosphate/growth performance/phosphorus utilization分类
农业科技引用本文复制引用
徐树德,王树启,游翠红,张敏智,张婷,杜红方,史宝军..中性植酸酶替代磷酸二氢钙对黑鲷生长和磷利用的影响[J].中国水产科学,2014,(3):522-530,9.基金项目
广东省海洋生物技术重点实验室开放课题(GPKLMB201302) （GPKLMB201302）
