浸泡对浮性饲料粗蛋白含量及水质的影响

在11℃与25℃下,测定养殖池水浸泡浮性饲料24 h后粗蛋白及水体中总氨氮和总磷含量的变化。试验结果表明,随着浸泡时间的延长,饲料粗蛋白逐渐下降,而水体总氨氮和总磷浓度逐渐升高。浸泡4 h,25℃组饲料粗蛋白从初始(29.983±0.262)%降至(12.930±0.339)%,降幅56.9%,极显著高于11℃组的下降幅度(P<0.01),浸泡24 h,2个温度组饲料粗蛋白均下降80%以上。浸泡24h,11℃组和25℃组水体中的总氨氮浓度由初始的(0.135±0.001)mg/L分别增至(0.427±0.003)mg/L和(0.590±0.002)mg/L;总磷含量由初始的(0.075±0.001)mg/L分别增至(1.199±0.002)mg/L和(1.271±0.008)mg/L。建议在养殖过程中,尤其是高温季节,尽量缩短浮性饲料在水中的停留时间。

Effects of Soaking Treatment on Crude Protein Level in Floating Feed and Related Water Quality

The changes in crude protein,TNH4-N and TP levels were monitored in the water in the floating feed soaked for 24 h in a pond at water temperature of 11 ℃ and 25 ℃.It was found that the crude protein levels were decreased gradually,being declined from(29.983±0.262)% to(12.930±0.339)% at 25 ℃(over 80% after 24 h),very significantly higher than that at 11 ℃(P<0.01),while the TNH4-N and TP levels were increased gradually in 24 h.The TNH4-N level was found to increase from(0.135 ±0.001) mg/L to(0.427±0.003) mg/L at 11 ℃ and to(0.590±0.002) mg/L at 25 ℃after 24 h.The TP levels were found to be increased from initial(0.075±0.001) mg/L to(1.199±0.002) mg/L at 11 ℃ and to(1.271±0.008) mg/L at 25 ℃ after 24 h,suggesting that the floating feed be fed as soon as possible after administration,especially in hot seasons.