Antanaitis Ramūnas, Džermeikaitė Karina, Šimkutė Agnė, Girdauskaitė Akvilė, Ribelytė Ieva, Anskienė Lina
Large Animal Clinic, Veterinary Academy, Lithuanian University of Health Sciences, Tilžės Str. 18, LT-47181 Kaunas, Lithuania.
Department of Animal Breeding, Veterinary Academy, Lithuanian University of Health Sciences, Tilžės Str. 18, LT-47181 Kaunas, Lithuania.
Animals (Basel). 2023 Jun 2;13(11):1852. doi: 10.3390/ani13111852.
The aim of this study was to evaluate the influence of the temperature and humidity index on reticulorumen parameters such as temperature, pH, rumination index, and cow walking activity levels. Throughout the experiment, the following parameters were recorded: reticulorumen pH (pH), reticulorumen temperature (RR temp.), reticulorumen temperature without drinking cycles, ambient temperature, ambient relative humidity, cow walking activity levels, heat index, and temperature-humidity index (THI). These parameters were registered with particular smaXtec boluses. SmaXtec boluses were applied on 1 July 2022; 24 days were the adaptation period. Measurements started at 25 July 2022 and finished at 29 August 2022. The THI was divided into two classes: THI < 72 (comfort zone) and THI ≥ 72 (higher risk of thermal stress). Cows assigned to the 2nd THI class had lower average values for pH, temperature, and rumination index, but not walking activity levels. The mean differences ranged from 0.36 percent in temperature to 11.61 percent in walking activity levels ( < 0.01). An analysis of the THI revealed a significant positive linear relation with hours, where the THI had a tendency to increase on average by 0.2403. The reticuloruminal pH showed a negative linear relation with hours, where the reticuloruminal pH had a tendency to decrease on average by 0.0032, < 0.001. Data analysis revealed a significant positive linear relationship between walking activity levels and hours, where walking activity levels had a tendency to increase on average by 0.0622 steps per hour, < 0.001. The rumination index was not significantly related to hours ( < 0.005), although the rumination index had a tendency to increase by 0.4376 per hour, > 0.05. The influence of HS on reticulorumen parameters increased the risk of acidosis and cows' activity levels. HS had a negative impact on reticulorumen pH, temperature, and the rumination index. A higher THI (≥72) increased the risk of ruminal acidosis and decreased cows' physical activity levels. From a practical point of view, we can use innovative tools for the detection of HS and its impact on reticulorumen parameters and cow walking activity levels.
本研究的目的是评估温度湿度指数对网瘤胃参数的影响，如温度、pH值、反刍指数和奶牛行走活动水平。在整个实验过程中，记录了以下参数：网瘤胃pH值（pH）、网瘤胃温度（RR temp.）、无饮水周期的网瘤胃温度、环境温度、环境相对湿度、奶牛行走活动水平、热指数和温度湿度指数（THI）。这些参数通过特定的smaXtec药丸进行记录。smaXtec药丸于2022年7月1日应用；24天为适应期。测量于2022年7月25日开始，于2022年8月29日结束。THI分为两类：THI < 72（舒适区）和THI≥72（热应激风险较高）。分配到第二类THI的奶牛的pH值、温度和反刍指数的平均值较低，但行走活动水平没有降低。平均差异范围从温度的0.36%到行走活动水平的11.61%（<0.01）。对THI的分析显示与小时数呈显著正线性关系，其中THI平均有增加0.2403的趋势。网瘤胃pH值与小时数呈负线性关系，其中网瘤胃pH值平均有降低0.0032的趋势，<0.001。数据分析显示行走活动水平与小时数之间存在显著正线性关系，其中行走活动水平平均每小时有增加0.0622步的趋势，<0.001。反刍指数与小时数无显著相关性（<0.005），尽管反刍指数有每小时增加0.4376的趋势，>0.05。热应激对网瘤胃参数的影响增加了酸中毒风险和奶牛的活动水平。热应激对网瘤胃pH值、温度和反刍指数有负面影响。较高的THI（≥72）增加了瘤胃酸中毒风险并降低了奶牛的身体活动水平。从实际角度来看，我们可以使用创新工具来检测热应激及其对网瘤胃参数和奶牛行走活动水平的影响。
