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Building a couple of outdoor enclosures costs much less than building many cages. An area of 110 square meters has capacity for 200 free-range rabbits and ten breeders. It would require 25 cages with eight growing rabbits per cage to match the free range system. Also, breeding requires their own individual cages with nesting areas, which means ten extra cages.
Rabbit urine is high in ammonia, which will endanger their health if not cleaned often enough; commonly results in a cold, a disease that has a high mortality rate. In nature, and outdoor enclosures with soil floors, urine is safely absorbed into the soil.
Rabbits produce two types of droppings, one of which they need to digest again. It contains necessary nutrients and beneficial bacteria that are crucial for rabbit health. In the cage system, these droppings fall through the mesh and cannot be accessed by the rabbit.
The cage system requires more time and work to clean. First it is necessary to remove the urine-soaked droppings from under the cages. Then the floors and cages need to be disinfected regularly. An outdoor system is self-cleaning as nature does the work for us. The urine, as already mentioned, is soaked and the droppings are dried in the sun and on the ground, making them inert. Once or twice a month, the droppings can be raked up and ready to be used as organic fertilizer.
Another time- and labor-intensive responsibility is feeding the rabbits and maintaining a constant supply of water. In addition, feeders and drinkers must be disinfected daily. As you can imagine, this job is also much faster with one or two enclosures than with 35 cages.
Rabbits have minimal sweat puffs and struggle to stay cool in hot weather. In the cage system they have no way to regulate their temperature; the farmer has to provide cooling systems such as insulation or air conditioning units. When temperatures reach 30 degrees, the sperm of male rabbits shrinks and becomes misshapen; the infirmary becomes dehydrated and is unable to lift their kits. In outdoor enclosures, rabbits can build burrows that are cool and allow them to escape the heat. Alternatively, the farmer can provide them with a couple of shelters to escape the elements.
Rabbits in cages are extremely stressed, bored and aggressive towards each other, resulting in low immunity to disease, increased food consumption and injuries from fighting. Free-range rabbits feel safe together, stay entertained, which results in healthy immune systems, less feed (nervous rabbits use more energy), and fewer injuries.