Long-Day lighting in dairy barns
Ideas for more
efficient dairy
farming.
by Gunnar Josefsson,
Marcia Miquelon and
Larry Chapman
University of Wisconsin, Madison
Healthy Farmers, Healthy Profits Project
Worth
considering!
Most dairy barns are too dark. Improving your barn lights and
operating them according to a specific schedule can improve both the profitability
and working conditions on your dairy farm. This technique is known as
Long-Day Lighting or Photoperiod Control. It has been well researched
in the past 20 years.
Benefits include:
• Increased milk production
• Improved heifer growth
• More enjoyable and safer working conditions
A profitable investment
Studies have shown that exposing cows to supplemental light during the
short days of fall and winter can increase milk production by about 5-16%.
However, cows also eat more, and there is a cost to install and operate
the lights. The increased milk yield pays for the extra feed and the cost
of the lights - and still leaves a net profit. Estimated investment costs
and pay-back periods for lights in a 40 cow tie-stall barn range from
$1,672 paid back in 111 days (Chastain, 1996) to $2,125 paid back in 332
days (Stanisiewski and Tucker, 1986).
Recommended light
program
16-18 hours of light and 6-8 hours of dark per day. Most of the experiments with Long-Day Lighting have provided supplemental light extending the fall/winter days (September- March/April) to 16-18 hours of light per day. The effects of this technique are well documented, and you can expect a substantial production increase by using a consistent program of 16-18 hours of light followed by 6-8 hours of darkness. Note that consistent night/off and early am/on timing is necessaryto achieve an increase in milk production.
Supplemental lighting: Profitable in any stall
barn or freestall barn.
A safer, more productive place to work
Trivial accidents (slips and falls) do happen during barn chores. They
may be disabling and are occasionally fatal. Good lighting helps workers
spot obstructions and slippery areas. Better lighting also makes it easier
to notice cows in heat, health problems, cows off feed, low feed quality,
etc. In addition, most people appreciate a well-lit work place and, consequently
may become more productive.
Improved lighting in conventional stall barns
Cows are stimulated to produce more milk when they register longer days through their eyes and brain. The average light intensity in the barn needs to be at least 15 foot-candles at cows’ eye level. This can be achieved by installing sealed fluorescent light fixtures over the manger. You should avoid using incandescent lamps since they are not energy-efficient and have a short bulb life. In most stall barns, natural daylight is insufficient. Therefore, the manger lights need to also be on during the day. To ensure consistent light/dark periods, a timer should be installed.
