Next gen aviary perches: A marvel good for environment, birds & farmers
This 3-year project starts in the fall of 2023 and will test the heated perch’s effectiveness as a method for reducing cold stress
By Tianna Charlson & Lesa Vold, Egg Industry CenterResearchers are working to turn ordinary laying hen housing perches into a potential tool to help improve sustainability while addressing climate change.
Climate change is defined as a long-term change in average weather patterns that is expected to worsen the frequency and intensity of extreme weather events. Climate change faces all of agriculture, including the egg industry. As a result, many individuals are working on understanding the various ways climate change can impact farms, an effort which coincides with the egg industry’s commitment to measure and improve sustainability on farms.
Dr. Richard Gates, Director of the Egg Industry Center and Iowa Egg Council Endowed Professor of Agriculture and Biosystems Engineering and Animal Science at Iowa State University, has been working on hatching a plan that could potentially reduce the impact of climate change’s extreme weather events on the egg industry and potentially increase a farm’s sustainability footprint – no matter where a facility may be located within the country.
The background
To understand the concept, some background about poultry anatomy is important. Poultry lack sweat glands and their coat of feathers significantly reduce their ability to dissipate heat. Conductive heat exchange in poultry is only effective in a few areas of the body, but especially in their highly vascularized legs and feet. Therefore, when the hen’s feet come in contact with an object, its surface temperature can be important. Since the industry has already experienced an increased frequency of hot days and unexpected heat waves in the last fifty years, and these scorching temperatures can cause heat stress in the birds, the researchers started there.
The first invention
“The idea started with a cooled perch system,” said Gates. “Our team looked at utilizing the perch because it already benefits laying hen welfare, and there are thousands of feet of perches throughout a house that we can potentially utilize to improve the thermal comfort of birds.”
Since approximately 25% of the body heat of a chicken can be lost through its feet, the idea was to create a closed system that utilizes constant chilled water flow to maintain a specific perch surface temperature.
Gates, along with a team of researchers, have performed several successful studies on the effect of cooled perches on laying hens using three hundred and twenty-four Hy-Line W-36 White Leghorns during a multi-year study. Researchers tested the effects of the cooled perch in a variety of situations. The cooled perch system helped alleviate symptoms in hens with repeated or chronic heat stress with and without induced molt. Hens with access to cooled perches maintained egg production and performance levels under hot conditions, compared to those on perches without any cooling.
“We were excited to see the cooled perch effectively help mitigate heat stress conditions in laying hens, improve their welfare status, and substantially improve production performance,” said Gates.
Achieving the bigger idea
Because the perch is a key furnishing in today’s modern cage-free aviary for its promotion of natural behaviors, the successful completion of the cooled perch work allowed Gates to start to see his original idea taking shape.
“The larger innovative idea for the industry has always been the creation of a ‘thermal perch’ that can be used in both hot and cold climates,” said Gates. “With the promising work completed on the cooled perch, we were ready to expand our work into heated perches.”
Armed with the concept of turning perches into energy-efficient systems to mitigate all thermal stress, Gates engaged four Engineering students at Iowa State University to design, build, and test a heated perch prototype as part of their senior capstone course. This course gives students the opportunity to complete projects that mimic real-world engineering needs. Through the course students were able to bring the heated perch prototype to life and find a way to maintain a constant perch surface temperature amid small ambient room temperature fluctuations.
Looking towards the future
Since the heated perch prototype was only tested under engineering laboratory conditions, without birds, further research is needed to assess the design’s long-term performance and assess its effects on hen welfare and production. Dr. Heng-Wei Cheng, Livestock Behavior Unit, USDA-ARS at Purdue University, will be continuing the heated perch work in a newly awarded USDA research project.
This 3-year project starts in the fall of 2023 and will test the heated perch’s effectiveness as a method for reducing cold stress. To test the heating capabilities of the perch, birds will be observed in controlled chilled rooms during the study.
The inspiration of these next generation “thermal perches” is leading the way to research and development of a universal system that can be used in both hot and cold climates and various times of the year. In the future, egg farmers may be able to utilize innovative heat pump technology to improve hen comfort, decrease energy costs and bolster egg productivity year-round in all sorts of climates.
Gates is thrilled to see this work advancing. “This work has the potential to be good for the birds, good for the environment, and good for the farmers,” said Gates. He finishes his statement as he grins, “Researchers don’t always find a single idea that innovates across so many important impact areas like this, so it’s a great feeling when we do – this is a tri-fecta.”
