Animal Industry Report

Extension Number

ASL R3267



Summary and Implications

The objective of this experiment was to determine the relationship between rectal temperature and infrared temperature measured on the inner eye, center- and ear base of sows undergoing anesthesia. A total of six sows were used. Sows were anaesthetized using a combination of xylazine, tiletamine HCl and ketamine. Thermal images at the inner ear, ear center and ear base were taken at 10 minute intervals starting ten minutes’ post-anesthetic induction until the sow was able to stand or reached 91.7◦ F body temperature. Rectal temperatures were measured using a digital thermometer. Rectal temperature Pearson correlations were determined among the inner eye, center and ear base with a significance level set at P ≤ 0.05. Percent variation accounted for by these locations was calculated as the correlation coefficient (r) raised to the second power and multiplied by 100 (r2 x 100). There was a positive correlation between rectal and inner eye, ear center and base (P ≤ 0.03). The lowest correlation was between the ear base and accounted for 9% of the sows’ rectal temperature variation. The correlation was the greatest for the inner eye and accounted for 38% of the sow’s rectal temperature variation. In conclusion, thermal images of the inner eye provided an effective and less invasive approach to rectal temperature for sows undergoing anesthesia.

Copyright Holder

Iowa State University