Abstract
The objective of this study was to determine the effects of chick pipping location on live broiler performance. A total of 1,350 hatching eggs were collected from a commercial flock of Ross 308 at 38 wk of age. Eggs were incubated with either their large end up (LEU) or small end up (SEU). After transfer on d 19, the air cell area of each fertile egg was marked with a marker pen on the egg surface with a candling light and monitored every 6 h during the hatching period to accurately determine the location of the pip hole. Chicks were classified into 3 groups: 1) egg position LEU and pipped through the air cell (LAC); 2) egg position SEU and pipped through the air cell (SAC); and 3) egg position SEU and pipped through the small end of the egg, not through the air cell (SSE). Individual BW was recorded at placement and at 7, 21, and 35 d of age. Feed consumption was also determined at 7, 21, and 35 d of age. The feed conversion ratio (FCR) was calculated on a pen basis for the same time periods. Mortality was recorded twice a day, and percent mortality was calculated throughout the study. The European production efficiency index (EPEI) was also calculated. All chicks that hatched from LEU eggs emerged from the egg at the region of the air cell; however, only 10.3% of chicks from the SEU position hatched through air cells. Pipping location greatly affected the hatch time. Chicks pipped through the air cell location hatched earlier than the chicks pipped without using air cell (P < 0.001). The initial BW at placement was higher in the LAC and SAC groups than in the SSE group (P < 0.001). This BW difference was still evident in the subsequent growing period, and the chicks that pipped the SSE exhibited a lower (P = 0.059) BW at 35 d. Additionally, the SSE group had a poorer FCR and numerically higher mortality than the other two groups at 35 d. Overall, the EPEI values in the LAC and SAC groups were higher than that in the SSE group at 35 d (P < 0.001). We concluded that broiler performance was negatively affected when the chicks pipped and hatched without using air cells.