Skin surface temperature of broiler chickens is correlated to body core temperature and is indicative of their thermoregulatory status

Abstract

Extreme thermal conditions may dramatically affect the performance of broilers and other domestic animals, thereby impairing animal welfare and causing economic losses. Although body core temperature is the parameter that best reflects a bird's thermal status, practical and physiological obstacles make it irrelevant as a source of information on the thermal status of commercial flocks. Advances in the technology of infrared thermal imaging have enabled highly accurate, noncontact, and noninvasive measurements of skin surface temperature. Providing that skin surface temperature correlates with body temperature, this technology could enable acquisition of reliable information on the thermal status of animals, thereby improving diagnoses of environmental stress in a flock. This study of broiler chickens found a strong positive correlation between body core temperature and facial surface temperature, as recorded by infrared thermal imaging. The correlation was equally strong at all ages from 8 to 36 d during exposure to acute heat stress with or without proper ventilation and after acclimation to chronic heat exposure. A similar correlation was found by measurements in commercial flocks of broilers. Measurements of blood plasma concentrations of corticosterone, thyroid hormones, and arginine vasotocin confirmed that metabolic activity was low after acclimation to chronic exposure to heat, whereas ventilation was at least as efficient as acclimation in reducing thermal stress but did not impair metabolism. In light of these novel results, commercial benefits of infrared thermal imaging technology are suggested, especially in climate control for commercial poultry flocks. The application of this technique to other domestic animals should be investigated in future experiments.

Carcass and meat quality traits of chickens fed diets concurrently supplemented with vitamins C and E under constant heat stress

“…It is likely that cardiovascular adjustments related to acclimatization, such as the vasomotor response, adaptations in the circulatory system, as well as reduction in heat production were taking place during this 2-week heat stress period (Yahav, 2009). These results are in agreement with previous studies in which increased core body and skin surface temperatures in broilers resulted from elevated ambient temperature over a period of 3 to 4 weeks (Cooper and Washburn 1998;Giloh et al, 2012).…”

Cyclic variations in incubation conditions induce adaptive responses to later heat exposure in chickens: a review

“…Proteosynthesis and proteolysis signaling pathways in the muscle were also reported to be affected by 2 weeks of heat exposure (Boussaid-Om Ezzine et al, 2010). In the long term, chronic heat exposure has been described as increasing plasma volume expansion (Whittow et al, 1964;Yahav et al, 1997) and inducing a redistribution of blood flow, especially toward peripheral tissues (Wolfenson, 1986;Giloh et al, 2012). Such physiological responses probably enhance sensible heat loss.…”

Thermal profile of broilers infected by Eimeria tenella

“…These statements were confirmed in our measurements. The highest temperature differences were found out in the bill and in the shank .Authors [14] refer to a strong positive correlation between body core temperature and surface temperature in chickens. Authors [13] present that thermal comfort is of great importance in chicken to preserve body temperature homeostasis.…”