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在早期哺乳乳期的奶牛中,超基托拉和产量之间存在关联
Z M Kowalski1, M Sabatowicz1, R J Van Saun2
1Department of Animal Nutrition and Biotechnology, and Fisheries, University of Agriculture in Krakow, Krakow, Poland 31120.
Journal of dairy science
|September 7, 2023
概括
乳母牛的超凯托拉症 (HYKL),定义为乳酸 (mACE) 和β-基酸盐 (mBHB),影响牛奶产量和成分. 具体的型影响了生产变化的严重程度,突出了对潜在的生化机制进行进一步研究的需要.
科学领域:
- 乳牛的新陈代谢 乳牛的新陈代谢
- 类动物营养 类动物营养
- 动物生产科学 动物生产科学
背景情况:
- 超化症 (Hyperketolactia,HYKL) 是一种乳牛的代谢状况,其特点是牛奶中的体含量增加.
- 了解乳酸 (mACE) 和β-基酸 (mBHB) 在HYKL中的不同作用,对于管理乳牛群的健康和生产率至关重要.
研究的目的:
- 为了研究不同类型的超球症 (HYKL) 与荷尔斯坦乳牛的牛奶生产特征之间的关联.
- 为了区分乳酸 (mACE) 和β-基酸盐 (mBHB) 在早期哺乳期对牛奶产量和成分的影响.
主要方法:
- 在5年期间 (2014-2019) 从荷尔斯坦乳牛收集的约500万份牛奶样本的分析.
- 使用富里埃变换红外光谱法 (FTIR) 量化牛奶 (mACE) 和β-基酸盐 (mBHB).
- 根据定义的值,将其分为四个类别:常态 (NKL),HYKLBHB,HYKLACE和HYKLACEBHB.
- 使用线性模型进行统计分析,以评估 ketolactia 组,牛奶中的天数 (DIM),平价以及它们对生产结果的相互作用的影响.
主要成果:
- 31.2%的牛奶样品被归类为HYKL,其中HYKL是最常见的亚型 (52.6%).
- 与NKL奶牛相比,HYKLACEBHB奶牛的奶产最低,而HYKLBHB和HYKLACE奶牛在整个哺乳期对奶产的影响不同.
- 在 ketolactia 群体中观察到牛奶成分的显著差异,包括改变的牛奶脂肪 (MF),牛奶蛋白 (MP) 和牛奶乳糖 (ML) 含量,特别是在 HYKLACEBHB和HYKLBHB奶牛中.
结论:
- 超托拉症 (HYKL) 显著与乳牛的乳制量和成分发生变化有关.
- HYKL对生产的影响取决于特定的型,包括乙 (ACE),β-基酸盐 (BHB) 或两者.
- 需要进一步的研究来阐明HYKL背后的生化途径,特别是早期哺乳期单独或与mBHB结合的mACE升高.
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