# Cooling Effectiveness of the Sustainable Cooling Solution for Cattle: Case Study in Poland
## 3 Results
### Cow's Response to the Novel Cooling System  
The cooling effect of the water mattress was also monitored through the evaluation of the cow's behavioral reaction, as well as skin temperature measurements of selected body regions, monitored with IR thermography, and finally the rumen temperature of the studied animal. Thermograms showing the thigh and abdomen area taken 1 min after the animals got up from the bedding area are presented comparatively in Figure 10. The average skin temperature for the thigh and abdomen, which were in direct contact with the chilled surface, was reduced even by 8 \({}^{\circ}\)C compared to the cows lying on the reference beddings (CowM and CowS). Cows' skin temperature variability within the thigh and abdomen area over 7 min after they got up are presented in Figures 11 and 12, respectively. The results for each cow are linearly fitted. The thigh temperature plots of the cow lying on the cooling water mattress are characterized by a much lower temperature at the beginning of the considered 7 min-long time period and by a high increase during this interval, in comparison to the results achieved for two other referenced cows. Another considered parameter is cows' reticulorumen temperature (Table 1). In the conducted experiment, the rumen temperature of examined cows, considered as the main trend presented in the Figure 13 curve, was slightly oscillating around 39 \({}^{\circ}\)C, which is a natural value [29]. \begin{table}
\begin{tabular}{l c c c} \hline \hline \multirow{2}{*}{**Parameter**} & \multicolumn{3}{c}{**Cows**} & \multirow{2}{*}{**SEM**} \\ \cline{2-2} \cline{4-4}  & **CowCM** & & **CowS** \\ \hline \hline \multicolumn{4}{c}{Day measurements (08:00 *–22:00)} \\ Reticulorumen temperature, \({}^{\circ}\)C & 38.48 \({}^{\text{a}}\) & 38.50 & 38.64 \({}^{\text{b}}\) & 0.024 \\ Activity & 5.72 \({}^{\text{A}}\) & 7.86 \({}^{\text{B}}\) & 8.47 \({}^{\text{C}}\) & 0.062 \\ Temperature without drinking, \({}^{\circ}\)C & 38.87 \({}^{\text{A}}\) & 38.76 \({}^{\text{B}}\) & 38.94 \({}^{\text{C}}\) & 0.023 \\ Heat index & 2.08 \({}^{\text{A}}\) & 3.20 \({}^{\text{B}}\) & 5.34 \({}^{\text{C}}\) & 0.141 \\ Reticulorumen temperature after drinking, \({}^{\circ}\)C & 37.63 & 37.25 & 37.33 & 0.073 \\ Drinking parameter ** & 28 & 24 & 36 & - \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Changes in reticulorumen temperature and indices measured by bolus sensors. Figure 10: Thermograms taken 1 min after the animals got up from their bedding areas (temperature scale in \({}^{\circ}\)C). Figure 11: Cows’ skin temperature in the thigh area within 7 min after animals got up. Figure 12: Cows’ skin temperature in the abdomen area within 7 min after animals got up. According to Figure 13, the characteristics of the temperature drops for CowM and CowS remained similar among the experimental days, but for CowCM the temperature difference in each drop was smaller in the following days of the experiment. On the last day of the experiment, which was characterized by the highest THI (c.f. Figure 7), temperature drops were more frequent than in other cows, but achieved a maximum value of 1.2 \({}^{\circ}\)C, contrary to 2.3 \({}^{\circ}\)C and 2.8 \({}^{\circ}\)C for CowS and CowM, respectively. Counting the mentioned temperature drops according to the applied methodology, the highest value of the drinking parameter was observed for the cow lying on straw bedding (CowS was 36 times vs. 28 times in the case of CowCM). A stable profile of the temperature around 39 \({}^{\circ}\)C can be observed in the nocturnal hours of the experiment. Behavior was another aspect taken into account for cows' welfare evaluation. For that assessment, the time budget of experimental cows, which includes time spent on standing and lying, was designated and summarized in Table 2, together with SE and \(p\)-values calculated for the average values of individual behaviors. The frequency (bouts) of these activities were also counted. Supplementary Materials provide additional data about cows' behavioral preferences.