If there are too many in the litter, transfer some to other litters (fostering), or if there are too few, bring in young from other litters. Fostering should be done a day or two following kindling and between litters that do not vary more than one to three days in age. Some does will accept kits of varying ages. The goal should be to form nursing groups of similarly sized kits with no more kits than available nipples.
Sometimes a doe fails to pull enough fur to cover her litter during cold weather. When you discover this, add fur from another litter or pluck fur from the doe’s body to cover the young before they are chilled. The fur is easily plucked at kindling time. If the temperatures are high and the doe pulls an excessive amount of fur, adjust the covering to the quantity needed to keep the newborn litter comfortable and save the surplus fur for an emergency when more may be needed for other litters. Inspect the litter periodically to make sure that the nest remains warm and dry and those dead kits are promptly removed.
Nest Box Management
To be satisfactory, a nest box should provide seclusion for the doe during kindling and protection and comfort for the litter afterwards. There are many types, and no one nest box is suitable for use in all rabbitries and in all seasons. Different kinds are discussed in Chapter 4, “The Rabbitry and Its Equipment.”
The bedding material should be pliable, absorbent, and of the type the doe can mix with the fur she pulls from her body, with the choice depending upon availability and upon type of nest desired. Straw, hay, wood shavings, leaves, cottonseed hulls, etc., can be used. If the does are being fed a ration consisting only of pellets, they may eat any palatable material used for bedding. Soft wood shavings or unpalatable bagasse may be used. During the warm season, less bedding is needed. When low temperatures prevail, the nest box should be filled more completely with bedding material.
Shredded paper is a poor absorbent, excelsior is harsh and does not mix readily with the fur, and both of these materials may cause suffering or death of the kits by becoming wrapped around their legs or necks. Shredded redwood bark and peat moss stain the coats, and the dust from them irritates the respiratory tracts of the young rabbits.
It has often been said that “the litter is made in the nest box,” and during the time the young rabbits spend there, their weight should increase seven to eight fold. A very important aspect of this is the milking ability of the doe, which can be assessed by the 21-day weight of the litter.
Kits will begin to develop hair within about 4 days after birth, and the eyes will open at about 10 days. The nest box may be removed when the litter is 15 to 21 days old, but the time for taking it out should be determined by the weather conditions. If it is necessary to keep it in the cage longer, it should be thoroughly inspected periodically and any soiled bedding replaced with clean. The longer the nest box is left in, the more likely that eye infections and other disease problems will develop, so the nest box should be removed as early as possible.
Does usually nurse their litters once per day. One management practice used quite extensively in Europe is to remove the nest box and put the litter in with the doe for only about five minutes per day. She usually jumps in and feeds the kits. Removal of the nest box reduces mortality caused by the doe jumping in several times a day and trampling some of the litter. With the use of a front-loading nest box (Fig. 4.16), the opening can be closed to keep the doe out except for a once-per-day nursing.
After the nest boxes are removed, they should be thoroughly washed and disinfected. They should be stored where wild rodents cannot get to them, as the smell of rodent urine may cause does to refuse to use the nest boxes.
Fostering Young
Frequently, does give birth to a larger number of young than they can nurse. It is good herd management to foster a doe’s excess kits to another doe with a smaller litter. In raising Angoras or rabbits for the meat market, there is a distinct advantage in reducing the size of a large litter to the number that the doe can develop uniformly. In the case of show rabbits it is especially important to reduce the litter even to four or five so that the young can have an opportunity to develop to the maximum of their inherited possibilities.
In order to distribute the transferred young for fostering, it is advisable when planning the breeding program to mate several does each breeding day so that several will kindle at about the same time. Each newborn litter should be inspected as soon as possible after the doe has quieted down following kindling, and a notation made of the number to be removed from or added to each litter. When all the does due at that time have kindled, the surplus young should be removed and permanently marked with a tattoo, ear punch, etc., so that the transferred young in each litter can be identified at weaning. If all the kits are to be marketed as fryers, identification may not be necessary.
When transferring the young it is not necessary to use any method for destroying the scent of the human hand or the scent of the dam of the young being transferred. Does do not make any distinction of young, even if they are of different colors or sizes (Fig. 5.13). Fostering is more successful if the largest kits are moved to the new doe and the smallest left with their mother.
Fig. 5.13. A Palomino doe nursing kits of a different breed. Does readily accept fostered kits even if they are of different sizes and breeds. (Courtesy of J.I. McNitt)
When selecting litters for fostering, it is advisable to watch carefully for any evidence of infection among the litters or does, as the transfer procedure could be a means for spreading disease. Under no circumstances should kits be fostered from a doe with mastitis to another doe, because the young can carry the bacteria and may infect the mammary glands of the foster mother.
Causes of Losses in Young Litters
Disease accounts for only a small percentage of the mortality that occurs the first week following kindling. Most losses during this time are due to improper equipment or incorrect feeding and management methods. Some cases may be due to the doe failing to produce milk. You can diagnose this by feeling the doe’s mammary tissue to determine whether it is producing milk (Fig. 11.6). If it is not nursing the litter, the milk glands will be undeveloped and the young will be shriveled and wrinkled. If she is nursing the kits, the udder will be well developed, and when the teats are stripped, there will be evidence of milk. The well-nourished young will be plump, and the milk line may be detected through the abdominal wall, depending on how recently they have nursed. If the doe has not produced any milk, it may be because the ration she received during the gestation period was inadequate in quantity or quality.
For a variety of reasons, does having a first litter often do not use the nest box and have their litter on the floor of the cage. Does should not be culled at this point, but if a doe has her second litter “on the wire”, culling should be considered. The use of drop nest boxes helps to reduce the problem.
At kindling you will obtain better results by making it possible for the doe to be secluded and undisturbed. Many losses of new litters are caused by the presence of strangers in the rabbitry when the doe is due to kindle or by the presence of strange cats or dogs or the natural enemies of the rabbit, such as opossums, rats, and snakes. These predators sometimes cause trouble in the city as well as in the country. Even if they cannot gain access to the cage, they may be so close that the doe can detect their presence, and instead of going into the nest box to kindle, she may kindle on the cage floor. If she has already kindled when she discovers the presence of predators, she may jump into the nest box in an attempt to protect her litter, and because she is frightened, she may stamp with her hind feet and crush her young.