PURPOSE: We determined whether experimental testicular torsion results in gonadal cooling and whether testicular temperature changes can be detected by infrared thermography. MATERIALS AND METHODS: A nonblinded, randomized, controlled trial was done in 6 anesthetized sheep. Thermocouple probes recorded testicular temperature every 15 minutes for 6 hours after experimental side 720-degree medial testicular torsion with orchiopexy or control side sham procedure with orchiopexy and for 75 minutes after procedure reduction. Color Duplex ultrasound was done to control the experimental assignment. Mean hemiscrotal infrared thermography temperatures were calculated and nonparametric repeated measures analysis was performed to determine whether there were significant changes in temperature as a function of the experimental condition and time. RESULTS: Testicular torsion resulted in significant testicular cooling by probe and infrared thermography (p <0.05 and <0.0001, respectively), which was promptly reversed upon the reduction of experimental torsion. Two hours after experimental torsion the median temperature difference (control side minus torsion side) was 2.5C for the probe and 1.7C for infrared thermography. CONCLUSIONS: Experimental testicular torsion resulted in significant gonadal cooling that was detectable by infrared thermography of the hemiscrotum. The applicability of these findings to the clinical setting remains to be determined.