The effect of red or blue lighting has not been studied
in ducks, leading to speculation as to whether red or
blue light would improve the ducks’ production, performance,
and well-being.
Information regarding environmental light is perceived
by the brain through photoreception via well
described pathways from the pineal gland and retina.
However, photoreceptivity by the brain is not limited
to these 2 structures. In birds there is evidence for
nonretinal photoreception. Neither bilateral enucleation
and/or pinnealectomy affect the seasonal changes in
reproductive status (Oliver and Bayle, 1982). Thus,
in birds there is compelling evidence that nonvisual
photoregulation of physiological homeostasis may be
mediated—at least in part—by deep encephalic photoreceptors
(DEP; (Li and Kuenzel, 2008). Although
the relative contribution of the retina compared to the
DEP in immature, grow-out ducks is not known, alterations
in photoneuroendocrine factors that affect feeding
and growth could ultimately alter production yields
and meat quality.
Meat quality is an important concern within the
poultry industry. Light is involved in growth and