Daily variations in the thermoregulatory behaviors of naked neck broilers in an equatorial semi-arid environment

Abstract

The aim of this study was to evaluate the daily variations in the thermoregulatory behavior of 4- to 6-week-old naked neck broilers (Label Rouge) in an equatorial semi-arid environment. A total of 220 birds were monitored for 5 days starting at 0600 hours and ending at 1800 hours. The period of observation was divided into classes of hours (C H). The observed behaviors were as follows: feed and water intake, wing-spreading, sitting or lying, and beak-opening. A total of 14,300 behavioral data values were registered. In C H 2 (0900 hours to 1100 hours) and 3 (1200 hours to 1500 hours), the greatest average body surface temperature was recorded (34.67 ± 0.25 °C and 35.12 ± 0.22 °C, respectively). The C H had an effect on the exhibition of all behaviors with the exception of the water intake behavior. Feed intake was more frequent in C H 1 (0600 hours to 0800 hours) and 4 (1600 hours to 1800 hours). In C H 2 and 3, the highest frequency of sitting or lying behavior was observed. Beak-opening and wing-spreading behaviors occurred more frequently in C H 3 where the body surface temperature (35.12 ± 0.22 °C), radiant heat load (519.38 ± 2.22 W m(-2)), and enthalpy (82.74 ± 0.36 kJ kg(-1) of dry air) reached maximum recorded averages. Thus, it can be concluded that naked neck broilers adjust their behavior in response to daily variations in the thermal environment. Wing-spreading and beak-opening behaviors are important adaptive responses to the thermal challenges posed by the equatorial semi-arid environment.

The Effect of Phytogenic Additive on Behavior During Mild-Moderate Heat Stress in Broilers

“…Previous studies have reported that broilers exposed to high ambient temperatures spent more time with sitting or lying behavior. Beak opening and wing spreading occurred more frequently in the highest daily temperatures and especially in connection with the highest body surface temperature and the highest radiant heat load (De Queiroz et al, 2013). High temperature reduced feed intake and also protein and energy intake (Syafwan et al, 2012).…”

“…The effect of semi-arid equatorial environment on daily behavior of naked-neck broilers were studied by De Queiroz et al, (2013). Numbers of panting birds and birds with elevated wings increased with increasing air temperature, the highest percentage of thermoregulatory behavior was observed between 12h and 15h at temperatures around 34 °C.…”

Broilers’ behavioural adjustments when submitted to natural heat stress and fed different maize particle sizes in the diet

“…Only 5% of the broilers drank water during the hottest times of day (10:00-14:00 h). This can be attributed to the gene expression of naked neck broilers (Fathi et al, 2013) and the ability of the birds to adjust their behaviour to the thermal environment (Queiroz et al, 2014). Among the behaviours exhibited in thermal challenge situations are open wings and panting (Attia et al, 2006;Wang et al, 2018).…”

Use of Protection Screen in Conventional Aviaries (Californian Type) for Laying Hens

“…Many authors have pointed out that the thermal discomfort conditions are limiting factors for the development and production of animals with high genetic value (Jácome et al, 2007;Carcalho, 2012;Feize et al, 2012;Tinôco et al, 2014). In laying hens, thermal discomfort causes a series of consequences, which are closely linked to a lower growth rate, decrease in feed intake, change in feed conversion, higher water consumption, accelerated heart rate, decrease in egg production, and a higher incidence of soft-shelled eggs (Jácome et al, 2007;Furtado et al, 2011;Silva et al, 2012;Allahverdi et al, 2013;Kilic & Simsek, 2013;Mack et al, 2013;Queiroz, 2014). In addition, according to Jácome et al (2007) and Carvalho (2013), the thermal comfort of birds must be planned from the design of the facilities, choice of materials, and equipment used.…”