Dep. of Environmental Science and Technology, Univ. of Maryland, College Park, MD 20742, USA.
J Environ Qual. 2009 Dec 30;39(1):324-32. doi: 10.2134/jeq2009.0139. Print 2010 Jan-Feb.
Adding phytase and 25- hydroxycholecalciferol (25-OH D(3)) to broiler diets has been shown effective at reducing total P concentrations in broiler litter. This study was conducted to determine the impact of field application of broiler litter from modified diets on P solubility in litter-amended soils and P losses in runoff. Five broiler diets and their resulting litters were evaluated: a high P diet, a low P diet, each of those basal diets with phytase added, and a low P diet with phytase and 25-OH D(3) added. A field study was initiated at two sites with each of the five broiler litters and a commercial P fertilizer (triple superphosphate [TSP]) applied at the same total P rate (150 kg P ha(-1)) and a control where no P was applied. Soil P was monitored over time at two depths (0-5 cm and 0-15 cm) soils were collected in the spring and fall to perform rainfall simulation studies. Broiler litter or TSP application increased soil water-soluble P and Mehlich 3-P concentrations relative to the control, however there were no consistent differences detected between litter treatments. Results from the rainfall simulation experiments indicate that diet modification with phytase or 25-OH D(3) does not increase the potential for P losses in runoff from amended soils relative to traditional diets. Moreover, broiler diet modification to reduce excreted P could be a potentially effective method for reducing watershed scale P surpluses in areas of intensive broiler production, without raising concerns over soluble P losses from litter-amended soils.
在肉鸡日粮中添加植酸酶和 25-羟胆钙化醇（25-OH D(3)）已被证明可有效降低肉鸡粪便中的总磷浓度。本研究旨在确定改良日粮的肉鸡粪便在田间应用对改良土壤中磷的溶解度和径流中磷损失的影响。评估了五种肉鸡日粮及其产生的粪便：高磷日粮、低磷日粮、分别添加植酸酶的基础日粮，以及添加植酸酶和 25-OH D(3)的低磷日粮。在两个地点开展了一项田间研究，用五种肉鸡粪便中的每一种以及等量的商业磷肥（过磷酸钙[TSP]）（150kg P ha(-1))，并设置了一个不施磷肥的对照。监测了一段时间内两个深度（0-5cm 和 0-15cm）土壤中的土壤磷含量，春季和秋季采集土壤进行降雨模拟研究。与对照相比，肉鸡粪便或 TSP 的施用增加了土壤水溶性磷和 Mehlich 3-P 的浓度，但粪便处理之间没有发现一致的差异。降雨模拟实验的结果表明，与传统日粮相比，日粮中添加植酸酶或 25-OH D(3)不会增加改良土壤径流中磷的潜在损失。此外，减少排泄磷的肉鸡日粮改良可能是减少集约化肉鸡生产地区流域尺度磷过剩的一种有效方法，而不会引起对改良土壤中水溶性磷损失的担忧。
