Thermal imaging to measure scrotal surface temperature and its use as a tool for breeding soundness evaluation of Zebu bulls

Abstract

The present study was planned to understand the effect of scrotal surface temperature on semen quality and Infrared thermography as a tool for breeding soundness evaluation of Zebu bulls. The thermal imaging of the scrotum revealed significant differences in temperatures from the neck to the ventral portion of the scrotum. The average neck and ventral temperature of the scrotum was 34.2±0.62°C and 31.22±0.53°C, respectively. The average gradient temperature of the scrotal surface (neck-ventral) was 2.95±0.30°C with a range of 1.2-5.7°C. The MA of bull semen (3.12±0.04 vs. 1.89±0.13), live sperm (73.82±0.88% vs. 59.42±1.58%), HOST (66.67±1.52% vs. 55.49±1.14%) and sperm concentration (1226.36±18.80 vs. 942.19±23.47m/ml) were significantly more in good semen quality bulls than poor semen quality bulls. Total sperm abnormality was significantly lesser in bulls having a larger scrotal temperature gradient. The scrotal skin thickness was significantly more in poor semen quality bulls than good semen quality bulls (5.70±0.12 vs. 5.07±0.13). The scrotal skin thickness was found highly correlated (r-0.77) with the scrotal temperature gradient. So it can be concluded that scrotal surface temperature is related to the semen quality of bulls, and thus the thermal imaging can be used for breeding soundness evaluation of Zebu bulls.

Keywords

• Infrared thermography
• Scrotal skin thickness
• Scrotal surface temperature gradient
• Semen quality