Getting your finishing hogs to gain weight quicker may be as easy as changing the light bulbs.

Researchers at Germany’s Futterkamp Education and Research Centre replaced standard lighting with blue-tinted tubes in a room with 96 finishing hogs, and compared the performance with counterparts housed in an adjacent room featuring normal lighting.

“Blue lighting, with a wavelength of around 500 nanometers, is already accepted as having a calming effect on humans,” explains Christian Meyer, one of the researchers. Some banks and supermarkets are already using blue lighting.

“We decided to try out the idea with hogs. The main aim was to reduce aggression in the pens and thus related problems such as tail biting,” he adds.

The first trial has confirmed the blue lighting’s positive effect, using it at 50 lux (one lumen per square meter) during the day. Compared with the control group, the blue group fought with their pen mates less.

The researchers also found that the blue lights increased average daily gain by an average of 0.53 pounds.  This reduced time to market by 1.5 days.

Reachers followed the carcasses through processing and found that hogs housed with the blue light produced 0.62 percent more lean meat than the control group.

Meyer notes that additional trials are underway. He’s testing the blue-light effect in the farrowing house. “There is still much more work to

be done, but there could be a future for its calming effect in buildings where weaned pigs from mixed sources are penned together for the first time.” Other possible applications might be during animal transport and at the packing plant.

The researchers also are investigating whether blue or green lighting offers the greatest calming effect on hogs.