大黄鱼膨化颗粒与软颗粒饲料浸泡时间对溶胀率、溶失率及COD的影响

The effect of soaking time of extruded feeds and soft pellet diet for Pseudosciaena crocea on the swelling rate,the loss rate of dissolution and chemical oxygen demand( COD)

本研究分别测定了7种粒径的大黄鱼膨化颗粒饲料和5种粒径的大黄鱼软颗粒饲料入水后的溶胀率、溶失率和化学需氧量(COD),比较分析了这两种大黄鱼饲料的水中稳定性及对水质的影响。结果表明,浸泡1 h后膨化颗粒饲料溶胀率显著高于软颗粒饲料(P<0.01),溶失率显著低于软颗粒饲料(P<0.01);浸泡6 h时软颗粒饲料的COD值显著高于膨化颗粒饲料(P<0.01);这两类饲料的溶胀率、溶失率和COD值与浸泡时间、粒径大小均呈显著正相关。

In the present study, a serial of Pseudosciaena crocea feeds were assessed, which mainly included seven different types of extruded feeds and five different types of soft pellet diet. The research detected the stability and effect on water quality of the feeds by measuring the swelling rate, the loss rate of dissolution and chemical oxygen demand （COD） after being immersed. The result showed that the swelling rate of the extruded feeds was significantly higher than the soft pellet diet （P 〈 0. 01 ）, and the loss rate of dissolution of the extruded feeds was significantly lower than the soft pellet diet （P 〈 0. 01 ） after 1 h. The COD of the extruded feeds was significantly higher than the soft pellet diet after 6 h. There was significant positive correlation between the particle size and different time of two feeds and the swelling rate, the loss rate of dissolution and COD.