Rabbit Production - James I McNitt

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more food when nursing their own young and, consequently, cause more trouble in the rabbitry in the spring. Evidently they can locate the cage where a doe is kindling or where a litter has just been delivered by the scent of blood. The losses are more likely to occur at night, and the presence of the intruders may not be detected by the caretaker. The rabbits, however, generally give warning by stamping their back feet, and if this warning is heard, an immediate inspection of the rabbitry should be made.

      Feeding the Doe after Kindling

      Does reduce their feed intake prior to kindling. This may in part be due to a reduced gut capacity caused by the presence of the fetuses in the body cavity. Following kindling, as lactation begins, their feed intake increases markedly. It is desirable to gradually increase the amount of feed offered to a doe for the first week or so following kindling until full feed intake is reached. Sometimes a young first or second litter doe will suddenly die when the litter is one to four days of age (young doe syndrome). This may be due to a stomach hairball, which can reduce feed intake to zero. Sometimes apparently healthy litters will suddenly die at five or six days of age. This may be due to milk enterotoxemia, caused by overfeeding the doe following kindling. Be sure not to overreact and underfeed the doe, as this may reduce milk production excessively.

      If an intensive breed-back system (7 to 21 days) is used, consideration should be given to keeping a doe on full feed once she goes into production. With the advent of high fibermedium energy diets, dropping the doe back to a restricted diet during the last part of gestation after weaning the first litter may be unnecessary. In fact, the energy demands of almost continuous gestation and lactation may necessitate continuous full feeding.

      Weaning

      Litters may be weaned as early as 28 days of age. Milk production is declining by then, and the young are consuming solid feed well. Feed is used more efficiently if it is eaten directly by the fryers rather than eaten by the doe and converted to milk. There is a stress at weaning, which may cause the fryers to go off feed and lose weight for a few days.

      Be sure that the weaned rabbits know how to drink. If, after the first day of weaning, they have not eaten much, it may be a water problem. Put in a water crock; if they rush to it to drink, then you know they haven’t learned to drink from the automatic waterers. Put a toothpick in the valve or loosen the valve to make it drip slightly. This should quickly teach them to drink. Another method is to put in one or two older fryers to teach the newly weaned litter how to use the water valve. Weaning at an older age reduces this problem.

      Determination of Sex

      The sex of the young rabbits may be determined accurately a day or two following kindling. Sexing at that time is necessary when one sex may be needed to supply a market for either does or bucks for breeding purposes, when rabbits are being produced for laboratory work, or when Angora bucks are to be kept as “woollers,” in order that any surplus to be disposed of will be the undesired sex.

      The external organs of both sexes of the newborn rabbits have very similar appearances, and a special technique is required for identification of sex at an early age. To prevent the continual wiggling of the little rabbit, restrain it firmly but gently. Place it on its back in the palm of your hand, with its head extended toward the heel of the hand. Use the index finger to press the tail back and down. Press down on the sexual organs gently but with enough pressure to expose the reddish mucous membrane that, in the case of the buck, can be made to protrude sufficiently to form a circle; in the case of the doe, it will protrude and form a slit that will have a slight depression at the end next to the anus. In addition, the distance between the penis and the anus is greater than the distance between the vulva and the anus.

      Until the technique of sexing rabbits has been perfected (Fig. 5.14), it may be a good plan to sex the young at weaning and then practice with several at about three weeks of age. In the older rabbits, the vulva will have a definite slit appearance. The penis will develop a more tubular appearance. This will make it easier to determine the sex of the three-week-old rabbit. Constant irritation of the tender parts may be detrimental, so sexing should not be practiced on the same rabbit at short intervals.

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      Fig. 5.14. External genitalia of the male (upper) and female (lower) rabbit. (Courtesy of D.J. Harris)

      Tattooing and Ear Tags

      An efficient, permanent system for identification is a necessity. Tattooing figures or letters, or a combination of the two, in the rabbit’s ear does not disfigure it, is permanent, and is easily accomplished. When young are being fostered, a hand tattoo needle is satisfactory for making one or more dots in each kit’s ear so the transferred young can be identified. It is also used by many breeders for the regular tattooing work in the rabbitry; others prefer the plier or tongs with removable figures and letters. After the inside of the ear is thoroughly cleaned with alcohol, either instrument may be used to perforate the inner surface of the ear. Tattoo ink or India ink should be rubbed into the perforations immediately (Fig. 5.15). The registration number for purebred stock is usually tattooed in the right ear and the rabbit’s individual mark or number in the left ear. A tattoo box that has movable parts so it can be adjusted to different sized rabbits (Fig. 4.18) holds the animal steady so one person can do the tattooing.

      Fig. 5.15. A permanent identification mark tattooed in a rabbit’s ear (Courtesy of J.I. McNitt)

      Rabbits can also be identified by the use of ear tags. These are produced as wing bands for chickens and are available from poultry supply houses. They are easily inserted using a simple tool (Fig. 5.16). Ear tags are sometimes lost, so identification is not as permanent as with tattoos. One method to make eartags less vulnerable to loss is to fold the ear and insert the tag halfway across the fold. When the ear is straightened out, the tag will be in the middle of the ear and have less chance of snagging on something and tearing out. For temporary identification, marking the ears with a felt-tipped pen is useful.

      Fig. 5.16. An ear tag for easy identification. (Courtesy of OSU Rabbit Research Center)

      Care of the Herd in Hot Weather

      Rabbits must be protected from rain and sun. Good circulation of air throughout the rabbitry is a must, but strong drafts and winds should be avoided. It is essential that the animals have a supply of water available at all times. Temperature, humidity, and air currents all have a direct bearing, and each rabbitry is an individual problem. Adequate shade should be provided.

      Rabbits suffer more from heat than cold; it is necessary to give the herd special attention during periods of high temperatures. They are more uncomfortable in high temperatures the first few hot days in the season. Does that are well advanced in pregnancy and newborn litters are the most susceptible to injury. The does give evidence of suffering by excessive moisture around the mouth and nose and occasionally bleeding from the nostrils, rapid respiration, and restlessness; newborn litters by extreme restlessness. Rabbits that show symptoms

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