Broiler Research Indicates Lasers Are Environmental Enrichment Devices

AMES, Iowa — Motivating broilers to move using specially designed lasers can improve animal welfare and improve meat quality.

Research from Iowa State University shows that periodically projecting randomly moving dot-sized laser lights onto the floor of broiler pens stimulates the birds’ predatory instincts and encourages them to be more active. This is particularly important as broilers approach market weight and become more sedentary, which can negatively impact their quality of life.

Elizabeth Bobeck, associate professor of animal science, and Anna Johnson, professor of animal behavior and welfare, have teamed up with Signify, a livestock lighting company, to create a new, second-generation laser device for this research. . With support from the US Poultry and Egg Association, USDA and its National Institute of Food and Agriculture, they conducted a study to assess how these devices influence animal behavior.

“We were concerned that the birds would exercise more, be smaller and lose weight,” Bobeck said. “Instead, we found they spent more time walking around and engaging in more positive behaviors that improved weight gain and bone density.”

Broilers exposed to lasers walked more frequently and for longer distances than their counterparts in the control group. They also spent more time at feeders and waterers, gaining more weight and improving feed efficiency. Despite their increased activity, the birds in the treatment group did not have more lesions, scratches or blisters on their legs or body.

Bobeck and Johnson conducted subsequent studies to measure different aspects of broiler performance, meat quality, and stress in response to this biologically relevant environmental enrichment from lasers. In one experiment, they found that the level of serum corticosterone, a stress hormone, in the blood of broilers was actually lower when the birds were exposed to laser devices.

“We wanted to know if the laser is used, does it make the birds more anxious or frightened? The answer was no,” Johnson said. “One of the things we were mindful of when creating the lasers is to allow individual choice of the bird. If the broilers want to interact with the laser, they can; if they choose not to do, they can do that too. I think that’s a real benefit from a well-being perspective.

The size and movement of the new laser devices mimic the small insects that chickens naturally want to hunt. The lasers emit red light to attract birds’ attention and ensure animal and human safety.

“We chose red because we knew it would be an attractive color for broilers, but also from a safety perspective,” Bobeck said. “Other laser colors, like green, have a more intense wavelength and can be more damaging to the eyes.”

Unlike other forms of environmental enrichment for poultry, such as perches and platforms, laser devices do not need to be cleaned and disinfected between bird shipments. Johnson noted that this not only reduces the potential for the disease to spread, but also limits labor requirements.

“A device may need occasional tweaks or software upgrades, but for all intents and purposes, it will work on its own,” Johnson said. “It will be super attractive for producers.”

More than 30 undergraduates and several graduate students have participated in laser device research at Iowa State. The lasers are currently undergoing research trials in commercial containment to understand their usefulness in large operations. Bobeck and Johnson believe this type of environmental enrichment can also benefit small flocks, as well as other types of poultry, such as turkeys and laying hens.