减少食中的阴离子-离子差异,以减轻来自便的氨排放,而不会影响哺乳母牛的产量
Journal of dairy science
|March 4, 2026
概括
在奶牛料中减少食阴离子差异 (DCAD) 降低了来自物的氨排放. 补充棕酸或甲氨酸类似物恢复了牛奶脂肪产量,减轻了负面的生产影响.
科学领域:
- 动物科学动物科学
- 营养生理学 营养生理学
- 环境管理环境管理
背景情况:
- 饮食中的酸离子差异 (DCAD) 影响乳牛的酸平衡和氨排放.
- 之前的研究表明,减少DCAD饮食会减少氨排放,但会对牛奶产量产生负面影响.
研究的目的:
- 评估是否用棕酸或甲氨酸类似物补充减少的DCAD饮食可以降低氨排放,同时防止消极的生产反应.
- 评估这些饮食修改对干物质摄入量,牛奶产量,牛奶成分和血液酸状态的影响.
主要方法:
- 一个复制的平衡的4x4拉丁方形设计,配有16只中期哺乳期的荷尔斯坦牛.
- 四种饮食治疗:控制 (CON),减少DCAD (rDCAD),使用棕酸的rDCAD (rDCAD-PA) 和使用甲胺类同类物 (rDCAD-MA) 的rDCAD.
- 肥料化7天以测量氨排放量;监测料摄入量,牛奶产量和成分,以及血液/尿液参数.
主要成果:
- 与CON相比,低DCAD饮食 (rDCAD,rDCAD-PA,rDCAD-MA) 减少了干物质摄入量和牛奶产量.
- 与单独使用rDCAD相比,使用rDCAD-PA和rDCAD-MA补充剂恢复牛奶脂肪产量到CON水平.
- 低DCAD饮食降低了尿液pH值,导致便累积氨排放量减少18%,与CON相比.
结论:
- 减少DCAD通过降低尿液pH,显著降低奶牛便的氨排放.
- 补充棕酸或甲氨酸类似物可以减轻低DCAD饮食对牛奶脂肪产量和整体牛奶产量的负面影响.
- 这些发现表明,在不损害牛奶生产效率的前提下,牛奶农业的环境减缓战略是可行的.
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