乳牛仅白天冷却的影响与白天加夜冷却的影响
J B Gaughan1, K Sharman2, M R McGowan2
1School of Agriculture and Food Sciences, The University of Queensland, Gatton, Australia 4343.
Journal of dairy science
|June 2, 2023
概括
乳牛的增强冷却策略显著提高了奶产量,降低了乳房温度. 在减轻热应激效应方面,连续昼夜冷却 (EDN) 证明比仅白天冷却 (DC) 更有效.
科学领域:
- 动物科学动物科学
- 乳牛管理 乳牛管理
- 环境生理学环境生理学
背景情况:
- 热压对奶牛的生产力和福利产生负面影响.
- 有效的冷却策略对于在炎热的天气中保持牛奶产量至关重要.
研究的目的:
- 评估日夜增强制冷 (EDN) 与仅日制冷 (DC) 对哺乳乳奶牛的影响.
- 评估不同冷却模式对牛奶产量 (MY),乳头温度和喘气得分的影响.
主要方法:
- 120头多的荷尔斯坦-弗里斯牛被分为两组:DC和EDN.
- 电流网络组接受连续冷却,包括夜间干预,而直流组仅在白天接受冷却.
- 监测了乳液温度,奶牛活动和喘气得分,并进行了个别的牛奶产量测量.
主要成果:
- 增强的白天+夜间冷却 (EDN) 与仅白天冷却 (DC) 相比,导致每日牛奶产量显著增加 (+2.05公斤/母牛/天).
- 在EDN组中,体温度始终较低,特别是在热浪期间.
- 在严重的热浪之后,EDN奶牛的牛奶产量明显增加 (+3.61公斤/母牛/天) 与DC奶牛相比.
结论:
- 连续冷却,包括白天和夜晚,优于仅白天冷却,以减轻哺乳乳奶牛的热应激.
- 增强的冷却策略对牛奶产量和生理参数产生积极影响,在热应激条件下改善牛的舒适性和生产力.
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