In-ovo monochromatic green light photostimulation enhances embryonic somatotropic axis activity

• Published in: Poultry science Vol. 96; no. 6; pp. 1884 - 1890
• Main Authors: Dishon, L, Avital-Cohen, N, Malamud, D, Heiblum, R, Druyan, S, Porter, T E, Gumulka, M, Rozenboim, I
• Format: Journal Article
• Language: English
• Published: England 01-06-2017
• Subjects: Animals; Body Weight - radiation effects; Chick Embryo - growth & development; Chick Embryo - radiation effects; Growth Hormone - blood; Growth Hormone - radiation effects; Growth Hormone-Releasing Hormone - analysis; Growth Hormone-Releasing Hormone - radiation effects; Hypothalamus - metabolism; Hypothalamus - radiation effects; Insulin-Like Growth Factor I - metabolism; Insulin-Like Growth Factor I - radiation effects; Light; Liver - embryology; Liver - radiation effects; Ovum - radiation effects; Pectoralis Muscles - embryology; Pectoralis Muscles - radiation effects; Prolactin - blood; Prolactin - radiation effects; Receptors, Somatotropin - radiation effects; RNA, Messenger; somatotropic axis; development; in ovo photostimulation; growth hormone receptor; broiler
• ISSN: 0032-5791; 1525-3171
• DOI: 10.3382/ps/pew489

Previous studies demonstrated that in ovo photostimulation with monochromatic green light increases body weight and accelerates muscle development in broilers. The mechanism in which in ovo photostimulation accelerates growth and muscle development is not clearly understood. The objective of the current study was to define development of the somatotropic axis in the broiler embryo associated with in ovo green light photostimulation. Two-hundred-forty fertile broiler eggs were divided into 2 groups. The first group was incubated under intermittent monochromatic green light using light-emitting diode (LED) lamps with an intensity of 0.1 W\m2 at shell level, and the second group was incubated under dark conditions and served as control. In ovo green light photostimulation increased plasma growth hormone (GH) and prolactin (PRL) levels, as well as hypothalamic growth hormone releasing hormone (GHRH), liver growth hormone receptor (GHR), and insulin-like growth factor-1 (IGF-1) mRNA levels. The in ovo photostimulation did not, however, increase embryo's body weight, breast muscle weight, or liver weight. The results of this study suggest that stimulation with monochromatic green light during incubation increases somatotropic axis expression, as well as plasma prolactin levels, during embryonic development.