Combi, or combination, -style housing can offer the best of both worlds to producers uncertain about the long-term appeal of cage-free eggs. However, the systems run the risk of eventual rejection by North American welfare certifying bodies or consumers.

As the U.S. egg industry weighs housing changes spurred by the rapid shift to cage-free production, Egg Industry is publishing a series of articles discussing the pros and cons of three types of cage-free housing systems: aviaries, floor systems and combination, or combi, systems. This article focuses on combi systems.

Egg Industry surveyed cage-free housing manufacturers from around the world to gather input on their systems. Big Dutchman Inc., Farm Innovation Team GmbH (FIT), Jansen Poultry Equipment, Valco Companies Inc./Valli Spa, Potter’s Poultry International, Tecno Poultry Systems LLC, Vencomatic Group, Hellmann Poultry GmbH & Co. KG and Farmer Automatic Gmbh & Co. KG responded to the survey. 

What combi systems look like

Combi systems, also called convertible systems, typically provide aspects of both an enriched cage and an aviary housing system. The systems are multi-tiered with doors that can be opened, allowing birds to roam about like in an aviary system, or closed, effectively making it an enriched cage. Closed, the stocking density is comparable to conventional cages. Combis also provide egg and manure belts underneath housing tiers, nest areas for the hens to lay, and feeding and watering systems.

Tecno Poultry Equipment Voliera VS224

Tecno's Voliera VS224 can be switched from an aviary, shown above, to an enriched cage. It's capable of hosting a cage-free and conventional egg operation simultaneously in the same house. | Courtesy Tecno Poultry

Advantages of combi systems

Ideally, combis give farmers freedom to produce cage-free and conventional eggs with the same system depending on consumer demand. This convertibility has made combi systems popular with egg producers who are not sure if demand for cage-free eggs will grow fast enough to maintain a price premium. The suppliers said combi systems appeal to egg producers who are used to cage systems and looking for a cage-free configuration maximizing the number of birds in the house.

Because combi systems can be closed and operated as cages, they face the same challenges from welfare certifying bodies as aviaries with doors. Egg producers risk eventually losing the ability to sell their eggs as cage free if they install a combi system. Farmers can totally remove the doors to address the issue, however.

While the system is proving popular in the U.S. and Europe, according to the housing manufacturers, a limited number of companies who responded to Egg Industry’s survey make convertible housing. Big Dutchman, Farmer Automatic, Tecno and Val-Co make combis, while FIT, Hellmann, Jansen, Potter’s and Vencomatic do not.

Those that sell combis promote the system’s elevated stocking density. Holland, Michigan,-based Big Dutchman said its combi offers higher stocking density, between .20 to .25 birds per cubic foot, than any other housing system it sells. Farmer Automatic, based in Laer, Germany, said the combi is a secure investment for a farmer looking for housing with the highest possible stocking density that is adaptable to changing regulations and market preferences.

“Overall, convertible positions allow the producer to reap the benefits of total confinement while having the opportunity to open the cages … and produce cage-free eggs using the floor as additional square footage,” Val-Co, of New Holland, Pennsylvania, said in its response.


Valli Space Aviary

Valli's Space Aviary combines attributes of an enriched cage and a cage-free aviary. The doors, which can confine the birds, are shown in this photo. | Courtesy Val-Co/Valli

Safety or obsolescence?

Those that don’t manufacture the systems described a combi as being substandard for use as either a cage or an aviary because it lacks key attributes usually included in one of those two systems.

The "combi system has no future and is a quick fix,” Steinfurt, Germany,-based FIT said in its response.

Vechta, Germany, manufacturer Hellman recently stopped making combis due to its doubts about the system. It said combis are insufficient as cages and too expensive to be used as aviaries. They also lack key nesting equipment for layers and proper egg handling equipment.

Vencomatic, of Eersel, Netherlands, which does not make aviaries with closing doors either, said convertible systems offer the same benefits as aviaries with closing doors, but they too “are at risk of being picked apart by regulation or certification.” In Europe, it said, a ban on temporary confinement of most laying hens is looking more likely.

Already in the U.S., a major cage-free certifier – Humane Farm Animal Care – refuses to certify any cage-free system which confines the birds. Another major certifier, the American Humane Association, will certify those systems, but the policy is subject to change. The egg industry association United Egg Producers is not taking a stance on the issue, but that could change in the future.

Labor considerations

Because the combi offers aspects of conventional and cage-free housing, the labor needs vary depending on the configuration.

Cage-free housing can require as much as two to four times more labor and present unfamiliar management challenges to farmers. Because the birds can freely move about a cage-free system, more labor is needed for inspection, locating floor eggs, monitoring the bird’s well-being, and general bird management. Cage-free systems can also bring new costs into the equation such as increased ventilation needs to address increased airborne dust, and more lighting to drive bird behavior and prevent hens from laying floor eggs.

Housing system suppliers expressed concern about the the limited data available on how well the systems work in the field and the wide range of housing configurations being considered to retrofit older houses. Even some suppliers that sell combis expressed these reservations because they think some egg producers are putting their desire to maximize hens per cubic food over practical bird management factors, which could increase floor eggs and add to labor costs.