Received: January 16th, 2023 ; Accepted: April 27th, 2023 ; Published: May 15th, 2023 ; Correspondence: [email protected] aim of this study was to evaluate the effect of the thermal environment on
behavioral and physiological parameters of crossbred cows of different productivity levels
confined in a compost barn system. For this, air temperature (Tdb) and relative humidity (RH)
data were measured using sensors/registers and wind speed (Vair) was recorded with the aid of
an anemometer. Subsequently, these data were used to calculate the Temperature and Humidity
Index (THI). Bedding material variables (pH and humidity) were also evaluated. The animals
were evaluated for physiological variables (respiratory rate – RR and surface temperature – ST),
scores (body condition, locomotion and dirt) and behavior. The analyses were carried out on two
groups of cows (Group 1: high production vs. Group 2: medium and low production). The average
pH of the bedding material was 8.5, within the recommended range. In the case of the
physiological responses of the cows, the respiratory rate (RR) of Group 1 indicated better
conditions of thermal comfort in the morning vs. the afternoon. The system was efficient in both
groups based on body condition score, indicating favorable conditions for the health of the
animals. Regarding the behavioral evaluation, Group 1 and 2 were statistically similar and had
the longest rumination times, in relation to the other evaluated behaviors. Regarding active
periods, medium production were the most active. Regarding idle time, low production spent
more time idle than the other animals
