Physiological roles of avian eyes in light perception and their responses to photoperiodicity

Abstract

The eye is a vital sense organ under neuro endocrine regulation in order to allow sight in the bird. It responds to light stimulus and photoperiodicity of the environment of the birds, where they are reared. The effects of photo stimulation are mediated via the various components of the eye. The physiologic roles of avian eyes have been under-utilised in poultry management to enhance production and consequently, economic efficiency of the birds. Regulatory mechanisms of avian eyes' function, response of components to photo stimulation and utilisation of photoperiod to enhance production in poultry have been reviewed. In conclusion, avian eyes respond to light stimulation and photoperiod, and these responses may be utilised for commercial poultry production in terms of eggs and meat, as well as for improving the welfare of the birds.