Effects of Heat Stress on the Daily Behavior of Wenchang Chickens

Abstract

One-day old chicks were randomly distributed into acute heat stress (AHS) or persistent heat stress (PHS) groups. Each group was further divided into control (CK), and three AHS ages (1, 2,or 3 weeks of age) experimental subgroups. The chicks in AHS subgroups were submitted to acute heat stress (40 o C for two hours between 12:00 and 14:00 hours during the weekend) and the effects of heat stress on several daily behaviors were observed. At 8 days of age, the chicks of PHS subgroups were submitted to heat stress (40 o C daily). The heat treatment ceased during the weekends and the effects on the behavior were observed three times daily for three consecutive days. The results showed that, compared with the CK group, the duration and frequency of drinking and lying-down behaviors of the AHS birds increased, whereas the duration of feeding and standing significantly decreased (p<0.01). The time spent walking by PHS birds was significantly longer than that of the CK groups (p<0.01), and drinking was also significantly longer than that of the CK group and was significantly different when birds were three weeks old (p=0.05). When heat stress lasted for two and three weeks in PHS group, the duration of lying down was longer compared with the CK group; however, this behavior was significantly shorter than the CK group when birds were three weeks old (p<0.05). These results indicate that heat stress significantly affects the daily behavior of broilers, including feeding, drinking, lying, standing, and walking.

Physiological Responses of Slow-Growing Chickens under Diurnally Cycling Temperature in a Hot Environment

“…Exposing birds to high ambient temperature generates behavioral (Li et al, 2015), physiological and immunological responses, which have detrimental consequences to their productivity. Changes in heart rate, as well as in other cardiovascular variables and other metabolic systems also participate in the thermoregulatory processes by modulating heat dissipation (Olanrewaju et al, 2010;Lara & Rostagno, 2013).…”

Upregulation of TLR4 mRNA Expression Levels in Broiler Chickens Under Acute Heat Stress

“…It well known that poultry species, particularly broiler chickens, are more sensitive to high environmental temperatures and humidity levels than other domestic animals because of their feather cover, lack of sudoriferous glands, and fast growth rate (Piestun et al, 2013;Di et al, 2015). When the environmental temperature exceeds the optimal temperature range, broilers show signs of heat stress, including rise in body temperature, reduced feed intake, poor reproductive and growth performance, immunosuppression, and increased mortality (Kamboh et al, 2013;Zhao et al, 2013;Zhang et al, 2014;Lasagna et al, 2015;Li et al, 2015;Sun et al, 2015). Many studies have demonstrated the damage or injury of the heart, liver, and brain tissues, as well as and angiocarpy in chickens and rats under HS (Zhang et al, 2014;Quinn et al, 2015;Ito et al, 2015).…”

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

“…Bruno et al, (2011) proved that heat stressed broilers had higher water consumption, but lower frequency of drinker visiting. Li et al (2015) showed that drinking times and eating duration of broilers under persistent heat stress also gradually increased with the increasing weekly age.…”