Initial Evaluation of Sow Cooling Pad Coolant Protocols on Performance and Physiological Conditions Measured by Precision Animal Data System

Highlights The sow physiological heat stress indicators showed significant improvement with cooling pad use. Time-triggered coolant flows demonstrate significant potential to cool overheated animals. Temperature-triggered coolant flows have the potential to operate effectively and maintain animals. A sensor and data collection system for a sow cooling pad was evaluated within a farrowing barn environment. Abstract.Thermal stress in swine has numerous negative effects on animal productivity and well-being. Researchers have developed a hog cooling pad that previous continuous coolant flow testing has determined to be efficient in removing heat from a simulated animal, effective in its use of coolant, and simple to build and maintain. Preliminary live animal experimentation with a single, second-prototype design under intermittent coolant flow was conducted at the conclusion of bench testing within a farrowing barn environment. The cooling pad was installed in a farrowing crate and preliminary live animal heat transfer data were collected. Two series of tests were conducted, triggering the coolant flow by set time cycles and by temperature limits. Three different sets of ambient barn conditions were examined (23°C, 28°C, and 33°C). In addition to the thermal reaction of the cooling device, animal temperatures and respiration rates for the treatment animal and a control animal were also collected during the experimentation. During time-controlled testing, the rectal temperature of the cooled sow was lower than the control sow (P = 0.02). The skin temperature of the cooled sow was also lower than the control sow (P = 0.04), and the respiration rate of the cooled sow was lower than the control sow (P = 0.02). These results indicated that temperature-controlled cooling might work well for ‘maintenance’ operations, while a time-controlled flow could potentially be used to extract greater levels of energy from an overheated animal. Results were encouraging enough that further testing with larger sample sizes to confirm these results for both control protocols is planned. Keywords: Cooling systems, Heat transfer, Physiological stress indicators, Swine, Thermal stress.