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Nest boxes can be constructed from a variety of materials, including wood, metal, wire with disposable cardboard inserts, plastic, and clay pots. They may be open on top or have partial covers to provide protection in cold weather.

Wooden boxes without lids are used quite extensively as nest boxes throughout the year in those areas where winter temperatures are above freezing. They may be simple plywood boxes with a plywood floor that has holes drilled in it. An alternative is to use 3 mm hardware cloth for the floor (Fig. 4.13). A more protected box can be constructed. Cut one end of the box down to about 15cm. Nail a board across the top of the box at the back. Cut off the two projecting corners of the sides, slanting from the edge of the top board to the edge of the 15 cm board. The doe is able to get away from her litter and is often seen on top of the nest box. Some growers protect the edges of the boards with tin to prevent chewing. Satisfactory results have been obtained with nest boxes as small as 38 × 23 × 18 cm. Advantages of a smaller nest box are that the doe makes a more compact nest, the materials cost less, the box takes up less space in the cage, and the doe is less likely to use it as a resting area or as a latrine.

Fig. 4.13. A wooden nest box with a wire screen bottom. (Courtesy of J.I. McNitt)

Injury of a young litter by the doe jumping into the box may be prevented by a slight change in the nest box. A 15 × 15 cm door should be made in one end, approximately 15 cm from the floor. Before the young are old enough to get out of the box, the end with the opening is turned away from the cage wall so the doe can get into the box without jumping over the side. When the young are about large enough to get out of the box, in order to keep them in it a few more days, the box is turned so its opening is against the wall. By this time the doe is not likely to injure the young when she jumps over the side into the box.

A drop nest box (Fig. 4.14 and 4.15) has a number of advantages. The nest box is below the floor of the cage. This allows does to mimic the nesting behavior of wild rabbits in holes or depressions. A major advantage is that if the young rabbits do crawl out of the nest box or are carried out attached to a teat, they fall back into it as they are crawling around the cage. This reduces deaths from exposure of kits, because rabbits, unlike many other species, will not return their young to the nest. The use of drop nest boxes may also reduce the problem of does kindling on the wire. The disadvantage of a drop nest box is that a doe will sometimes use it as a latrine.

Fig. 4.14. A “drop” or “subterranean” nest box. (Courtesy of D.J. Harris)

The wire component of the drop nest box is made of 2.5 × 5.0 cm wire sides with a 1.25 × 2.54 cm wire floor. It is essentially a wire basket that is J-clipped to the bottom of the cage after a section of the floor (41 × 25 cm) is removed. This wire basket (41 × 25 × 20 cm) is permanently attached to the cage. A plywood insert (39 × 24 × 20 cm) with a screen bottom is built. The plywood insert is added to the cage whenever a nest box is desired. The insert is filled with nesting material prior to adding it to the cage. The doe will then add her fur to make the nest (Fig. 4.15). The plywood insert is removed 18 to 21 days after the kits are born and is emptied, washed, disinfected, and stored for the next use. To prevent the doe from using the nest box as a latrine, the wire basket can be built only 10cm deep. Then the insert (which is 20 cm tall) will be elevated 10cm above the cage floor and will help prevent the doe from fouling the nest. More chewing of the edges may be seen with the elevated nest and the advantage of the kits falling back into the nest is lost.

Fig. 4.15. A doe making a nest in a drop nestbox. (Courtesy of OSU Rabbit Research Center)

Another style of nest box is located outside the cage. It is attached to the front of the cage (Fig. 4.16). The litter is very accessible for inspection by the rabbit raiser, who can remove dead kits, etc., without opening the cage or disturbing the doe. The nest box can be equipped with a door so that the doe can be locked out of it. This prevents her from jumping into the box frequently and trampling the kits. Suitable inside dimensions of the nest box for most breeds are 41 × 25 × 41cm. The front-loading nest box should have a lid (Fig. 4.16) to prevent the doe from jumping out.

Fig. 4.16. A modern commercial rabbitry with front-loading nest boxes. (Courtesy of D.J. Harris)

A system that has been successfully employed in research studies to measure milk production is to lock the doe out of the nest box for all but one five-minute period per day. Since kits generally nurse only once each day, this is an adequate exposure to the doe. When the door is opened, the doe usually jumps in, nurses the litter, and then leaves. The use of this technique may reduce losses of kits due to trampling. It should be emphasized that if the does are stressed by visitors, unusual noises, etc., they may not jump into the nest boxes in the allotted time. This system requires a high level of management skill.

Various types of bedding can be used in nest boxes, including straw, wood chips, newspaper, sawdust, and shredded sugarcane products. The doe will supplement the bedding with pulled hair to make a nest (Fig. 4.17). Does may eat straw or hay used in the nest box; this is not necessarily a problem, as the ingested fiber may be helpful in preventing enteric diseases. Another innovation is the use of disposable nest box liners constructed of cardboard. These are removed and burned after use by one litter, which may have value in sanitation and disease control. Regardless of the type of nest box used, it should have adequate drainage.

Fig. 4.17. A well-filled drop nest box. (Courtesy of OSU Rabbit Research Centre)