Effect of two cooling systems on thyroid hormones and thermophysiological variables of lactating sows

ARQUIVO BRASILEIRO DE MEDICINA VETERINARIA E ZOOTECNIA(2019)

Cited 0|Views7
No score
Abstract
The effects of the evaporative cooling system with negative pressure (ECS) and water spray on the roof (WSR) on physiological variables, thyroid hormones and neutrophil/lymphocyte ratio (N:L) in lactating sows were evaluated. Sixty-one lactating females were divided in the two thermal environments, being 30 in SRE and 31 in the AAT shed in the summer. The air temperature and humidity, respiratory frequency (RF), surface temperatures (ST) and rectal (RT), serum thyroxine and triiodothyronine concentration, number of neutrophils and lymphocytes and the N/L ratio were determined. In the afternoon, the matrices in ECS (Tar: 25.0 degrees C and THI: 74.7) and WSR (Tar: 27.6 degrees C and THI: 77.3) were exposed to heat stress. In the morning, RF, ST and RT were lower in ECS (49 breaths.min(-1), 31.1 degrees C and 38.5 degrees C, respectively) than WSR (54 breaths.min(-1), 32.8 degrees C and 38.6 degrees C) and also in the afternoon ECS (55 breaths.min(-1), 30.3 degrees C and 38.8 degrees C, respectively) and WSR (65 breaths.min(-1), 31.4 degrees C and 39.1 degrees C, respectively). Animals under WSR shed presented lower concentrations of T4 than animals under ECS (37.84 vs 42.22nmol.L-1). In a tropical environment, in the summer, lactating sows of both systems maintain homeothermia.
More
Translated text
Key words
swine,heat stress,thyroid,welfare
AI Read Science
Must-Reading Tree
Example
Generate MRT to find the research sequence of this paper
Chat Paper
Summary is being generated by the instructions you defined