A study for reduction of eutrophils excretion from livestock.

集约化畜牧生产带来的大问题之一是粪便的过度生产和堆积。动物粪便中的氮和磷已成为造成地表、地表和内陆水体富营养化的主要原因。在低蛋白质日粮中添加合成氨基酸可以减少尿氮排泄量，提高蛋白质的生物利用率。在低效磷日粮中添加酶植酸酶，可以通过植酸的水解来降低粪磷产量。本研究的目的是在低蛋白质和低磷日粮中同时添加氨基酸和植酸酶来减少单胃动物的氮磷排泄。在粗蛋白质为14%、磷为0.4%的日粮中添加苏氨酸和植酸酶，可达到与粗蛋白质为16.8%、磷为0.6%的日粮相同的氮磷存留率，并可使生长期和育肥初期的氮排出减少25%、磷排出减少50%；在粗蛋白质为16.3%、磷为0.48%的日粮中添加合成氨基酸和植酸酶，可达到与粗蛋白质为20.5%、磷为0.64%的日粮相同的体重增长在肉鸡育肥初期可减少47%的氮排泄量和45%的磷排泄量。从本试验可以看出，同时添加合成氨基酸和植酸酶可以明显减少家畜的氮磷排泄，对环境造成了很大的负担。

One of big problems induced by an intensive animal production is an excess manure production and accumulation. Nitrogen and phosphorus from animal waste have become the major reason for eutrophication of ground, surface and inland water. The addition of synthetic amino acids to a low protein diet could reduce urinary nitrogen output with the improvement of protein bioavailability. And the addition of enzyme phytase to low available phosphorus diet could reduce fecal phosphorus output with hydrolysis of phytate.The aim of the present study is a reduction of nitrogen and phosphorus excretion from monogastric animals by the simultaneous treatment of amino acids and phytase on a low protein and phosphorus diet.The supplementation of lysine, threonine and phytase to a diet containing 14% of CP and 0.4% of phosphorus could reach the same retention of nitrogen and phosphorus as a diet containing 16.8% of CP and 0.6% of phosphorus and could reduce 25% of nitrogen excretion and 50% of phosphorus excretion during the growing period and the first period of fattening in pigs.The supplementation of synthetic amino acids and phytase to a diet containing 16.3% of CP and 0.48% of phosphorus could reach the same body weight growth as a diet containing 20.5% of CP and 0.64% of phosphorus and could reduce 47% of nitrogen excretion and 45% of phosphorus excretion during the first period of fattening in broiler.It is clear from this experiment that the simultaneous supplementation of synthetic amino acids and phytase can obviously reduce nitrogen and phosphorus excretion from livestocks which become a big burden against environment.