SILVA, A. A.; SILVA, Amanda de Araújo.
Resumo:
The present paper aims to evaluate the thermal environment effect
of the coast of Paraíba, in the city of João Pessoa – PB, over the behavior of the
physiological responses of acclimatized horses of the Military Police Cavalry –
Coronel Calixto Regiment, subjected to different thermal stress conditions, as
well as their thermoregulatory performance and ability to adapt during the dry
period. 12 crossbred horses aged between 7 and 15 years old, with light and dark
coats, healthy and active in their respective functions, were used. The
physiological variables measured were heart rate (FC), respiratory rate (FR),
rectal temperature (TR) and surface temperature (TS), the last one stand as the
average of the surface temperature of the forehead, neck, withers, arms, central
point of the ribs, abdomen, rump and leg. The physiological responses obtained
were subjected to the tests: ITC (heat tolerance index) and CA (adaptability
coefficient). The environmental variables collected and evaluated were air
temperature (TA), black globe temperature (TGN), relative humidity (UR), dew
point temperature (TPO). The statistical design was completely randomized and
the analyzes made included the effect of shifts, when in an exclusive condition of
shading and effect of the thermal stress conditions in the measurement times of
the parameter. It was possible to observe that the physiological values were
influenced, mainly by radiation and air temperature. The horses showed an
increase in respiratory rate and managed to keep the rest of physiological
parametres within the normal range for the species. The thermal environment of
the dry period of the coast of Paraíba interfered in the homeothermia of the
evaluated horses, causing, at times, a decrease in the heat dissipation in
sensitive form, but this was compensated by the heat dissipation in the latent
form, not being harmful to the ideal internal temperature for the species.