乳牛尿液和便分泌的预测:一个元分析方法
Joyce L Marumo1, P Andrew LaPierre1, Michael E Van Amburgh1
1Department of Animal Science, Cornell University, Ithaca, NY 14853.
JDS communications
|September 2, 2024
概括
开发乳牛 (K) 排泄的预测模型对于环境监测至关重要. 使用K摄入量的模型显示了尿液和便K排泄的最佳预测性能.
科学领域:
- 动物科学动物科学
- 环境科学 环境科学
- 农业科学 农业科学
背景情况:
- 量化乳牛中的 (K) 排泄对于评估乳牛养殖对环境的影响至关重要.
- 目前用于测量K排泄的方法往往是劳累和昂贵的.
- 经验数学模型为简化K排泄量化提供了一个有希望的方法.
研究的目的:
- 在乳牛中开发尿K (KUr) 和便K (KFa) 排泄的经验预测模型.
- 为评估效率和监测牛奶生产对环境的影响提供工具.
- 为了更好的农场管理,确定影响K排泄的关键因素.
主要方法:
- 利用了来自17项研究的已发表文献数据,分别涵盖了尿液和便中K排泄的45种和54种治疗方法.
- 采用固定效应的线性混合模型,包括K摄入量,干物摄入量 (DMI),食中的K含量,尿量,牛奶产量和水摄入量.
- 使用交叉验证评估模型性能,评估根平均平方预测误差 (RMSPE%) 和一致性相关系数 (CCC).
主要成果:
- 与便 (43.5 ± 21.0 g/d) 相比,尿液中的分泌量 (202.5 ± 92.1 g/d) 显著更高.
- 使用食K度的模型显示KUr和KFa的预测能力不佳.
- 纳入K摄入量的模型显示了KUr和KFa的优异预测性能,数据变化解释率>92%和最小偏差.
结论:
- 经验模型,特别是那些使用K摄入量的模型,可以准确地预测乳牛的K排泄.
- 减少K摄入量可能会减少K的分泌量,但足够的营养供应对于牛的健康和生产力至关重要,特别是在热应激下.
- 这些模型可以帮助管理环境影响,优化奶牛养殖中的营养利用.
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