植酸酶对金鳟粪磷及水环境中磷含量的影响

通过喷涂和预处理两种方法将不同浓度植酸酶添加到豆粕型金鳟(Oncorhynchus mykissW albaum)饲料中,研究了植酸酶对金鳟粪磷及养殖水环境中磷含量的影响。金鳟粪磷分析结果显示,喷涂法添加植酸酶,对照组中粪磷含量最高,其他各试验组较对照组差异显著(P<0.05),但500~2000 U/kg组中粪磷含量差异显著(P<0.05),2500~6000 U/kg组中粪磷含量无显著差异(P(0.05);预处理法添加植酸酶,对照组粪磷含量最高,其他各试验组粪磷含量较对照组降低显著(P<0.05),但添加植酸酶的各试验组之间差异不显著(P(0.05)。通过水中磷含量试分析结果显示,无论是喷涂法添加植酸酶还是预处理法添加植酸酶,各试验组水体总磷含量分别较其对照组差异不显著(P(0.05),各试验组的活性磷含量均未检出。实验结果表明,金鳟饲料中添加植酸酶可以降低粪磷含量,对养殖生产过程中控制磷的排放,减少磷污染具有重要的意义。

Effects of Dietary Phytase on Phosphorus Content in Faeces and Cultured Environment for Rainbow Trouts (Oncorhynchus mykiss Walbaum)

Different contents of phytase were supplemented in soybean meal-based diet of rainbow trout to study the effects of phytase on faecal phosphorus and cultured water phosphorus.The fecal phosphorus result showed that in phytase sprayed groups,the faecal phosphorus content of control group was significantly higher than the other test groups(P<0.05),and the faecal phosphorus contents differed significantly among 500～2000 U/kg groups(P<0.05),but there was no significant difference among 2500～6000 U/kg groups(P﹥0.05).In phytase pretreated groups,the control group had the highest faecal phosphorus content,but there was no significant difference among the other phytase pretreated groups.There was no significant effect of supplemented phytase on water total phosphorus content among all phytase sprayed groups(P﹥0.05);and the water labile phosphorous content of any group could not be detected,so did phytase-pretreated groups(P﹥0.05).From above analyses,dietary phytase for rainbow trout can decrease faecal phosphorus discharger,and have important significance on controlling phosphorus pollution.