Pontiggia Alice, Holinger Mirjam, Münger Andreas, Ammer Stefanie, Dohme-Meier Frigga, Keil Nina Maria
Centre for Proper Housing of Ruminants and Pigs, Swiss Federal Food Safety and Veterinary Office, Agroscope, Route de la Tioleyre 4, 1725 Posieux, Switzerland.
Ruminant Nutrition and Emissions, Agroscope, Route de la Tioleyre 4, 1725 Posieux, Switzerland.
Vet Anim Sci. 2025 Jul 16;29:100488. doi: 10.1016/j.vas.2025.100488. eCollection 2025 Sep.
We hypothesised that bringing full-time grazing dairy cows indoors during the hottest time of summer days could reduce heat stress if barns are cooler than outdoor. A 51-day pilot study on 19 pasture-based Swiss dairy farms revealed that, with daily mean ambient temperatures between 15 and 22 °C, barns were on average 2.5 °C cooler than pasture between 1000 and 1800 h. In an experiment over two summers, 38 Holstein dairy cows were investigated in 12 experimental periods of up to three consecutive days, with a mean daily comprehensive climate index between 23.6 and 28.5 °C. Cows experienced two treatments with a cross-over after each experimental period: half of the cows stayed on pasture full time except during milking, while the other half was brought inside the barn from 1130 h until afternoon milking and was supplemented with hay. During this time, barn conditions were cooler (mean and SD -2.9 ± 3.8 °C) than those on pasture. Between 0830 and 1100 h, when all cows were on pasture, no differences in physiological and behavioural indicators were detected in relation to treatment. Between 1200 and 1430 h, cows kept inside had lower vaginal temperature, reticular temperature, heart rate and respiration rate compared with those on pasture. Cows kept inside spent less time feeding and walking, but more time ruminating and lying down. These results suggest that bringing dairy cows inside during the hottest time of summer days reduces heat stress in grazing systems if barns are cooler than outdoors.
我们假设，如果牛舍比室外凉爽，那么在夏季最热的时候将全职放牧的奶牛圈养在室内可以减轻热应激。一项针对19个瑞士牧场型奶牛场的为期51天的试点研究表明，在日平均环境温度为15至22°C的情况下，在1000至1800时期间，牛舍平均比牧场凉爽2.5°C。在两个夏季进行的一项实验中，对38头荷斯坦奶牛进行了研究，实验为期12个阶段，每个阶段最长连续三天，日平均综合气候指数在23.6至28.5°C之间。奶牛在每个实验阶段后进行两种处理的交叉：一半奶牛除挤奶期间外全天都在牧场，而另一半奶牛从1130时起被带入牛舍直到下午挤奶，并补充干草。在此期间，牛舍环境比牧场凉爽（平均温度和标准差为-2.9±3.8°C）。在0830至1100时期间，当所有奶牛都在牧场时，未检测到与处理相关的生理和行为指标差异。在1200至1430时期间，与在牧场的奶牛相比，圈养在牛舍内的奶牛阴道温度、瘤胃温度、心率和呼吸率较低。圈养在牛舍内的奶牛进食和行走时间较少，但反刍和躺卧时间较多。这些结果表明，如果牛舍比室外凉爽，那么在夏季最热的时候将奶牛圈养在室内可减轻放牧系统中的热应激。
