When managing a healthy, productive flock, getting the lighting conditions right could be more important than you think. Melanie Epp checks in with the bright sparks who are shining a spotlight on the problem
In caged housing, laying hens respond well to artificial lighting. But as producers transition from traditional cages to aviaries, enriched colonies and free-range systems, questions about lighting have surfaced. Why is lighting important for poultry? And how do you choose the right lighting for each system? Two poultry specialists, Dr Ian Rubinoff, European account manager and technical services veterinarian at Hy-Line International, and Karen Schwean-Lardner, professor at the University of Saskatchewan in the department of animal and poultry science, share their expertise.
Why is lighting important for poultry?
In understanding why lighting is important in poultry production, it’s necessary to look at the birds’ biological make-up. In humans, light reaches the brain through the eyes. In chickens, light penetrates not only through the eyes, but also through the top of the skull, via the pineal gland, and through the pituitary gland next to the hypothalamus. Whereas in our eyes we have just three types of cones – specialised photoreceptor cells that are responsible for our perception of red, blue and green light – chickens have four: red, blue and green cones, as well as a cone for ultraviolet light.
Like humans, poultry’s lives revolve around a regular day-and-night cycle. When birds have a proper day and night cycle, they develop the proper diurnal rhythms – that is, a routine of typical activities during the day. This is important for functions like melatonin production. “It is a normal cycle that is so important for birds because it drives things like immune function and growth rate and reproductive hormones,” explains Schwean-Lardner. “By giving that day-and-night cycle, you improve the health of the birds, you improve the immune status, you improve mobility and you improve alertness.”
“Birds tend to be more active when they have a day-night cycle,” she continues. “They’ll actually grow better, which is really interesting and the total opposite of what was thought ten years ago.”