Early-age housing temperature affects subsequent broiler chicken performance.

The influence of housing temperature in early life on subsequent growth and development of broiler chickens was investigated. Hatchlings were exposed to an ambient temperature of 34 degrees C (NT) or 28 degrees C (LT) on d 1. Both temperature regimes decreased with 1 degrees C per day for 5 d. At d 6 the ambient temperature of the LT group was increased to the same ambient temperature as the NT group. At d 29 all chickens were exposed to 10 degrees C for 7 d. Navel temperature was lower in the LT group than in the NT group from d 2 to 5. Body weight of the chickens was higher in the NT group than in the LT group and the difference between both groups increased in time. Temperature treatment during the early post-hatching period did not result in a long-term alternation in organ development, haematocrit value, energy and protein metabolism or the occurrence of ascites. Although not significantly, the course of metabolism suggested that early thermal treatment had long-term effects. Before cold treatment in week 5, the NT group showed higher values for energy and protein metabolism than the LT group, but during cold exposure, the opposite was found. We concluded that exposure of chickens to a moderate reduction in house temperatures during early post-hatching life seemed to have long-term negative effects on the performance of these chickens, but, on the other hand, it seemed that these chickens were better prepared to withstand cold challenge later in life.