USDA-Agricultural Research Service, Genetics and Precision Agriculture Research Unit, MS 39762, USA.
Poult Sci. 2011 Jul;90(7):1397-405. doi: 10.3382/ps.2010-01114.
With global food demand expected to increase by 100% in the next 50 yr, urgency to combine comprehensive strategies for sustainable, efficacious, and environmentally sensible agronomic practices has never been greater. One effort for US meat bird management is to reduce NH(3) volatilization from litter to create a better growing environment for the birds, improve production efficiency, retain N in litter for fertilizer value, and negate the detrimental environmental impacts of NH(3) loss to the air. To derive the fundamental effects of temperature and moisture on litter NH(3) volatilization over the range of conditions found in commercial houses, experiments were conducted using commercial broiler litter that had moisture contents of approximately 20 to 55% while controlling temperatures ranging from 18.3 to 40.6°C. Litter samples (100 g) were placed in 1-L containers that received humidified air at approximately 113 mL/min. Volatilized NH(3) in exhaust air was captured in H(3)BO(3) traps. Ammonia loss (log(10) transformation) was modeled via an equation using linear coefficients for temperature and moisture, an interaction term for temperature × moisture, and a quadratic term for moisture. The surface responses resembled parabolic cylinders, indicating a critical moisture level at which NH(3) no longer increases but is diminished as moisture continues to increase. The critical moisture level lies between 37.4 and 51.1% litter moisture, depending on the temperature. An increase in temperature consistently increased NH(3) generation. When the temperature extremes were compared, the maximum NH(3) was up to 7 times greater at 40.6 vs. 18.3°C. The upper moisture limit at which NH(3) release is maximized and subsequently arrested as moisture continues to increase had not been defined previously for commercial broiler litter. The poultry industry and researchers can use these results as a decision tool to enable management strategies that limit NH(3) production.
随着未来 50 年全球粮食需求预计增长 100%，现在比以往任何时候都更需要综合策略来实现可持续、高效和环境合理的农业实践。美国肉禽管理的一项努力是减少垫料中的氨气挥发，为鸟类创造更好的生长环境，提高生产效率，保留垫料中的氮作为肥料价值，并消除氨气向空气中损失对环境的不利影响。为了了解温度和水分对商业鸡舍条件范围内垫料中氨气挥发的基本影响，进行了实验，使用的商业肉鸡垫料含水量约为 20%至 55%，同时控制温度范围为 18.3 至 40.6°C。将 100 克垫料样品放入 1 升容器中，容器接收约 113 毫升/分钟的加湿空气。废气中的挥发氨被 H 3 BO 3 阱捕获。通过一个使用线性温度和水分系数、温度×水分交互项和水分二次项的方程对氨损失（对数变换）进行建模。表面响应类似于抛物线柱，表明在水分继续增加的情况下，氨气不再增加而是减少的临界水分水平。临界水分水平取决于温度，在 37.4%至 51.1%的垫料水分之间。温度升高会持续增加氨气的生成。当比较温度极端情况时，40.6°C 时的最大氨气是 18.3°C 时的 7 倍。之前尚未为商业肉鸡垫料定义氨气释放达到最大并随着水分继续增加而随后停止的最大水分限制。家禽业和研究人员可以使用这些结果作为决策工具，以实施限制氨气生产的管理策略。
