Such fact suggests the action stimulant of the light from 20 weeks of age, when the bird already reached the sexual maturity, it became highly sensible when approaching to the adult phase, that is, 25 weeks of age. In this age, beyond the levels of LH, the levels of progesterone and estradiol they also reach the maximum, coinciding with the LHRH level, through the previous portion of hipotlamo. To mediated that the bird goes reducing its capacity of production, from 42-45 weeks of age, concentration of those hormones goes if reducing, conditional with the gradual fall of the production. (QUINTO LANA, GERALDO ROBERT. Poultry keeping 2ooo.) The potential capacity of egg production, would be determined by two factors: 1) speed of maturation of folculo bigger inside of the hierarchy to folicular and 2) fotoperodo or exposition of the bird and a certain amount of light natural and artificial, capable to stimulate the hipotlamo-hipfise-ovario axle. (QUINTO LANA, GERALDO ROBERTO.Avicultura 2ooo.) Recent studies (IESNA, 2001) show that the excellent duration of the daily light is of 14 h and that daily 17 values above of h can harm the egg production. As the visual system of the bird it answers the luminous radiations in the band of the visible specter between 664 and 740 nm, the light bulbs used in the aviaries must emit in this band.
The data (IESNA, 2001) also indicate that a minimum iluminncia of 10 lux is recommended for the egg production. Iluminncias superior the 10 lux do not lead to any good consideration and can harm the production, favoring behaviors of aggressiveness, hiperatividade and canibalismo. The iluminncia excess also harms the production of cut chickens causing, beyond the problems above cited, metabolic and circulatrias deposition of fat, greater incidence of problems of legs, illnesses. The necessity of modifications in the lighting systems of aviaries, normally equipped with great number of incandescent light bulbs, already comes being pointed out has some time (CEMIG, 1996) e, also, indicated for subject of project of energy eficientizao (ANEEL, 1999). has compatible beliefs. Taking in account such indications, the present work was developed with the objective of if diminishing the consumption of electric energy of the lighting systems of sheds of fertile egg position.