# Cooling Effectiveness of the Sustainable Cooling Solution for Cattle: Case Study in Poland
## 2 Materials and Methods
### Animals and Experimental Design  
This experiment was conducted in the Research and Didactic Station in Swojczyce (51.11\({}^{\circ}\) N, 17.15\({}^{\circ}\) E), which is a part of the University of Environmental and Life Sciences in Wroclaw, in the period 16-18 August 2022. Preliminary research was carried out with three milk-breed Friesian dry cows, which were approximately 5-6 years old. The number of units was justified by the already-applied tie-stall housing system and health control reticulorum bolus sensors for those animals. The decision-making process was based on the least interference in the animal's daily routine and well-being.  
The animals were housed in a barn equipped with natural ventilation, and no applied automatic regulation of any environmental parameters. Within the entire test duration, all animals had constant access to drinking water and were fed \"ad libitum\" twice per day at approximately 08:00 and 14:00. Since they were not lactating cows, the pasture was hay. As the element of the cows' routine management in the selected barn, each cow was observed daily for signs of sickness or discomfort by the zootechnical staff of the aforementioned research station. This study has been evaluated in accordance with current European legislation (directive 2010/63/UE) (the European Parliament and of the Council, 2010). During the experiment, no procedure that could cause pain, suffering, or distress was used. Only the environmental indicators and bedding parameters were measured, and for the assessment of animals interference was limited to a minimum by using previously applied reticulorum bolus sensors (protocol No. 053/2019).  
Each cow was lying down on a different type of bedding: the types proposed in this paper were the innovative cooling water mattress (CowCM), the commercially available commercial water mattress (CowM), and straw bedding (CowS). Using different types of beddings enabled comparison of their influence on animals' thermal comfort. The cows' assignment to the bedding was justified by technical and logistic reasons in the prototype cooling system application in the selected barn's infrastructure. It should be highlighted that cows resting on water mattresses had spent the previous 3 days acclimatizing to the new beddings before the initiation of the analyzed experimental period. The applied acclimatization period was indicated by the Guide for the Care and Use of Laboratory Animals [25] as the minimum recommended time period before minor procedures, which was considered sufficient since no invasive procedure was applied. Due to the fact that the proposed cooling water mattress was developed as a modification of the commercially available water mattress, the same model was selected as the reference to the conducted experiments. Commonly used straw was considered as the third type of bedding and the second reference used to estimate the cooling effect of the proposed cooling water mattress.  
Figure 3: Hydraulic scheme of the cooling water production and distribution system (RadMAT system) and its connection with an innovative cooling water mattress.  
Following the manufacturer's recommendation, the commercial waterbed was filled with water, and assembled with latex foam. Both mattresses were also provided with filled water kneeboards placed on the top of the mattress. All three bedding types applied during the experiment are presented in Figure 4.  
During all measurement days, the mattresses' surface temperature was measured in three locations: bottom, middle, and top. The measurement took place approximately every 1 h (between 9:00 and 18:00) and was carried out by a Visiofocus 06620 (Tecimmed, Vedano Olona, Italy) thermometer (accuracy rating \(\pm\)1 \({}^{\circ}\)C). The developed water mattress was continuously (24 h per day) driven by cooling water and monitored by a set of sensors, which collected a substantial number of records.