Abstract: This study evaluated the ability of an infrared thermometer to measure external scrotal temperature of rams. To validate the equipment surface and internal temperatures of water-filled bottles were measured using infrared and probe thermometers, respectively. There was a high correlation (R = 0.99, P < 0.0001) between internal and external temperatures of the bottles. The animal experiment was conducted using 21 mature hair sheep rams with dark (Barbados Blackbelly; n = 5; Dark) or light (St. Croix White; n = 14; Light) colored scrotums. Rectal temperature was measured with a veterinary thermometer. Using aseptic techniques and a local anesthetic internal scrotal temperature of three regions of the scrotum (proximal, middle, and distal) was measured using a probe thermometer and an infrared thermometer was used to determine surface temperature of the regions. Rectal temperatures of Dark and Light rams were 38.9 ? 0.2 and 39.1 ? .1 ?C, respectively. The temperature gradient for surface and internal scrotal temperatures was 2.9 ? 0.1 ?C and was not different (P > 0.10) between Dark and Light rams. Scrotal surface temperature of the proximal region was lower in Dark than in Light rams (33.9 ? 0.3 vs 34.9 ? 0.2 ?C, respectively) but there was no difference in the middle or distal regions. The Dark rams had a lower (P < 0.01) average surface temperature than the Light rams (32.9 ? 0.2 vs. 33.6 ? 0.1 ?C, respectively) but there was no difference (P > 0.10) between internal temperatures. There was a moderate, positive correlation (r = 0.65, P < 0.01) between the surface and internal scrotal temperatures of Light rams at the middle region. The hand held infrared thermometer can be used to measure the scrotal surface temperature of rams and may be useful in identifying rams with abnormal scrotal thermography.