Study of the difference in rectal and ear canal temperature according to the conformation of the acoustic conch in dogs

Abstract

The auditory thermometry has being used for measurement of temperature of dogs. However there is different acoustic conch conformation in this species, being that the pendulous ears can alter the auditory microclimate. This research aimed to study the difference of rectal and auditory canal temperatures according to acoustic conch conformation in dogs. One hundred and eleven dogs were used with erect ears (group I), semi-pendulous (group II) and pendulous (group II) with 37 animals each group. The measurement of rectal temperature (TR) was realized with traditional thermometer mercury column and measurement of both external ears temperature with infrared ear thermometer. The average hearing temperature (TAM) was obtained and realized difference between TR and TAM, being the results classify in scores, A=TAM<TR until 1.2°C and B=TAM<TR more than 1.2°C. The average of TAM was 37.15°C±0.81, whereas that TR was 38.68ºC±0.59. The average difference between TAM and TR was 1.53ºC±0.75. Seventy one ears (63.96%) were classify in the score B and 40 (36.04%) in the score A. The TAM average was 37.17°C±0.85, 37.35°C±0.50 and 36.93°C±0.96 respectively in groups I, II, III. There was no difference in the type of ear in TAM (p=0.5097). The average difference between the TR and TAM in the group I was 1.57°C±0.65, in group II 1.26°C±0.49 and in the III 1.76ºC±0.96. Predominated ears in the score B independent of type (p=0.7606). In the conditions of this study the average ear temperature is lower than the rectal temperature by 1.53°C±0.75 and the conformation of the ear does not influence the average ear temperature.