Influence of Incubation Temperature on Chicks Ventilation and Oxygen Consumption

Abstract

The first third of the incubation is determinant for the embryonic development and the temperature is considered one of the most important factors that can affect the quality and the survival rate of the embryos. The aim of this study was to evaluate the effect of changes in the temperature of incubation (36 °C‐cold; 37.5 °C‐thermoneutral and 39 °C‐hot) during the first 5 days on ventilation (VE) body temperature (Tb) and oxygen consumption (VO2) of 2 days old broiler males (M) and females (F) in basal conditions and under exposition to hypoxia (10% O2) or hypercapnia (7% CO2). No difference among groups was observed during room air conditions. Under hypercapnia, the VE of females exposed to cold incubation was lower compared to other treatments (P =0.0402 compared to control and P= value=0.0193 compared to hot), as well as the respiratory frequency (fR) when compared with hot treatment (P =0.0387), but not to the control situation (P = 0.1109). VO2 of females during CO2 exposure was higher in 36 °C group compared with other groups (P = 0.0004 compared to control; P =0.0078 compared to hot). VE and of control males was lower when compared to hot (P = 0.0344) and VT of the same group was lower than cold (P‐value=0.0171) and hot (P =0.0324) treatments. There was no difference in fR and VO2 among groups. Hypoxia promoted a higher VE (P = 0.0439) and VT (P =0.0041) in cold exposed females compared to hot. VO2 was higher (P = 0.0290) as well when compared to 37.5 °C group. No difference was observed in respiratory responses of males exposed to hypoxia. Therefore, temperature of incubation can affect the ventilation in young broiler chickens under hypercapnic and hypoxic conditions in a sex‐dependent manner.Support or Funding InformationFAPESP, CNPq and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior ‐ Brasil (CAPES) ‐ Finance Code 00