10.6084/m9.figshare.5176753.v1
Henrique Barbosa Hooper
Henrique Barbosa
Hooper
Fábio Luís Henrique
Fábio Luís
Henrique
Lina Fernanda Pulido Rodríguez
Lina Fernanda Pulido
Rodríguez
Alfredo Manuel Franco Pereira
Alfredo Manuel Franco
Pereira
Cristiane Gonçalves Titto
Cristiane Gonçalves
Titto
Evaldo Antonio Lencioni Titto
Evaldo Antonio Lencioni
Titto
Heat loss efficiency and thermoregulation responses of Nellore cows
CBBiomet 2017
2017
bos taurus indicus
ocular area thermography
vaginal temperature
Environmental Management
2017-08-08 14:44:13
Journal contribution
https://cbbiomet.figshare.com/articles/journal_contribution/Heat_loss_efficiency_and_thermoregulation_responses_of_Nellore_cows/5176753
<p>Nellore
cattle is well adapted to tropical environmental conditions with good
thermoregulatory characteristics. However, knowledge related to body
temperature regulation and acclimatization mechanisms are still scarce. This
investigation aimed to understand the heat loss efficiency and thermoregulation
responses of Nellore cows in tropical climate conditions. In this study was
used 16 healthy purebred Nellore cows classified by heat loss in efficient and
non-efficient using the vaginal temperature continuously monitored by
data-loggers. The rectal, tail and ocular temperatures, sweating rate and
respiratory frequency were also measured to understand the thermoregulatory
responses and correlate to previous classification. In our findings, were noticed
that according to heat loss classification the non-efficient cows showed greater
amplitude of temperature variation. The body temperature increased from 12:00 PM
to 19:00 PM with gradual decreased from 19:00 PM to 07:00 AM, reaching the peak
in both groups at around 16:00 PM. In addition, the efficient cows presented
higher sweating rate than non-efficient that presented higher rectal
temperature, therefore the reduction of body temperature by improving
evaporative mechanisms is a good trait of acclimatization to heat. No
statistical difference was observed for the other physiological variables
between groups. In conclusion, the methodology to classify the cows by heat
loss using vaginal data loggers allowed us to distinguish Nellore cows
according to their body temperature regulation, being feasible and reproducible.
Furthermore, the efficiency to heat loss of this bred was mainly associated
with sweating capacity. </p>