Effect of a photoperiodic green light programme during incubation on embryo development and hatch process
Q. Tong,
I.M. McGonnell,
T.G.M. Demmers,
N. Roulston,
H. Bergoug,
C.E. Romanini,
R. Verhelst,
M. Guinebretière,
N. Eterradossi,
D. Berckmans,
V. Exadaktylos
Affiliations
Q. Tong
Key Lab of Agricultural Engineering in Structure and Environment, China Agricultural University, Beijing 100083, China; The Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK
I.M. McGonnell
The Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK
T.G.M. Demmers
The Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK
N. Roulston
Research and Development, Petersime N.V., Centrumstraat 125, B-9870 Zulte (Olsene), Belgium
H. Bergoug
Anses, Ploufragan-Plouzané Laboratory, Avian and Rabbit Epidemiology and Welfare Unit, BP 53, 22440 Ploufragan, France
C.E. Romanini
Division M3-BIORES: Measure, Model & Manage Bioresponses, KU Leuven, Kasteelpark Arenberg 30, Box 2456, B-3001 Leuven, Belgium
R. Verhelst
Research and Development, Petersime N.V., Centrumstraat 125, B-9870 Zulte (Olsene), Belgium
M. Guinebretière
Anses, Ploufragan-Plouzané Laboratory, Avian and Rabbit Epidemiology and Welfare Unit, BP 53, 22440 Ploufragan, France
N. Eterradossi
Anses, Ploufragan-Plouzané Laboratory, Avian and Rabbit Epidemiology and Welfare Unit, BP 53, 22440 Ploufragan, France
D. Berckmans
Division M3-BIORES: Measure, Model & Manage Bioresponses, KU Leuven, Kasteelpark Arenberg 30, Box 2456, B-3001 Leuven, Belgium
V. Exadaktylos
Division M3-BIORES: Measure, Model & Manage Bioresponses, KU Leuven, Kasteelpark Arenberg 30, Box 2456, B-3001 Leuven, Belgium
This study was conducted to evaluate the effect of a 12-h light, 12-h dark (12L : 12D) photoperiod of green light during day 1 to day 18 of incubation time, on embryo growth, hormone concentration and the hatch process. In the test group, monochromatic light was provided by a total of 204 green light-emitting diodes (522 nm) mounted in a frame which was placed above the top tray of eggs to give even spread of illumination. No light–dark cycle was used in the control group. Four batches of eggs (n=300/group per batch) from fertile Ross 308 broiler breeders were used in this experiment. The beak length and crown–rump length of embryos incubated under green light were significantly longer than that of control embryos at day 10 and day 12, respectively (P<0.01). Furthermore, green light-exposed embryos had a longer third toe length compared with control embryos at day 10, day 14 and day 17 (P=0.02). At group level (n=4 batches), light stimulation had no effect on chick weight and quality at take-off, the initiation of hatch and hatch window. However, the individual hatching time of the light exposure focal chicks (n=33) was 3.4 h earlier (P=0.49) than the control focal chicks (n=36) probably due to the change in melatonin rhythm of the light group. The results of this study indicate that green light accelerates embryo development and alters hatch-related hormones (thyroid and corticosterone), which may result in earlier hatching.
