由于谷物养料场牛的高热量负荷而导致的全静止
Gene Wijffels1, Angela M Lees2, Megan L Sullivan2
1CSIRO Agriculture and Food, St Lucia, QLD 4067, Australia.
Translational animal science
|October 10, 2024
概括
越来越多的热浪影响了牲畜. 这项研究表明,经历模拟热浪的牛表现出生理变化,包括减少料摄入量和改变身体温度,即使热量下降后,也表明潜在的长期调整.
科学领域:
- 动物科学动物科学
- 环境生理学环境生理学
- 畜牧业管理 畜牧管理
背景情况:
- 全球热浪的强度,频率和持续时间正在增加,对牲畜健康,福利和经济生产力构成重大风险.
- 了解热应激的生理反应对于减轻高价值农业系统的不利影响至关重要.
研究的目的:
- 为了深入评估在模拟热浪事件和随后的恢复期间,谷物养的黑格斯牛的生理反应.
- 在受控的热量负载条件下,评估乳头温度,呼吸速率,喘气得分,用水量和干物摄入量的变化.
主要方法:
- 两个12头公牛的队伍在气候控制室 (CCR) 接受了三相模拟热浪:预挑战,挑战 (7天,THI 66-95) 和恢复.
- 在整个实验过程中,监测了体温度 (RumT),呼吸率 (RR),喘气得分 (PS),用水量和干物摄入量 (DMI).
- 在多个时间点测量直肠温度 (RecT),重点关注过渡期和恢复阶段.
主要成果:
- 在热挑战期间,公牛的Rumt,Rect,Rr和PS显著增加,同时DMI显著降低.
- 在从挑战前阶段过渡到挑战阶段时,观察到突然的生理变化.
- 热浪后的恢复显示了持续的变化:与基线前挑战水平相比,平均RumT,ReCT,RR,PS和DMI的降低 (大多数参数的P<0.05).
结论:
- 牛表现出对高热负荷的全静态反应,表明对热应激事件的显著生理调整.
- 在恢复期间观察到的持续生理状态表明,严重的热浪对牲畜的影响可能会在即时压力时期之外产生持久的影响.
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