Experience and Techniques for Winter Breeding and Management of Rex Rabbits

The management of raising Rex rabbits is extremely important, especially in winter, when temperatures are low, sunshine hours are short, and green fodder is scarce, which brings certain difficulties to rabbit raising. If feeding and management are improper, it will not only increase expenses due to higher feed consumption and higher disease and mortality rates, but also seriously affect fur quality, while also restricting the rapid development of production. The focus of winter feeding and management is to do a good job in cold protection and heat preservation as well as winter breeding and winter raising. The following points should be noted in the winter feeding and management of Rex rabbits.

Do a good job in cold protection and heat preservation. Rex rabbits fear heat and are relatively cold-tolerant, but their cold tolerance has a certain limit. When the temperature drops below 5°C, they will feel uncomfortable. Newborn naked, colorless kits are especially afraid of freezing; below 10°C they will become stiff with cold, and below 5°C they will freeze to death. Therefore, doing a good job in cold protection and warmth preservation in winter is very important for raising Rex rabbits well. 1. Although winter temperatures are low, except for newborn kits, the rabbit house temperature is not required to be very warm, but it is required to be relatively stable and not suddenly cold or hot. In winter, the optimal temperature for Rex rabbit growth should be 15°C~25°C. Excessive cold or heat has a relatively large impact on their physiological functions. Generally, it should not be lower than 10°C or higher than 29°C. 2. Increase stocking density and rely on body heat dissipation from the rabbits to raise the temperature; young and juvenile rabbits must not be raised in single cages, and kits must be moved into warm rooms. 3. When raising rabbits indoors, doors and windows should be closed well to prevent drafty wind from invading; when raising rabbits outdoors, straw curtains should be hung on cage doors to prevent cold wind from entering. The ventilation volume should be reduced to the lowest possible limit so as to preserve the heat produced by the rabbits' bodies. 4. Sufficient and reasonable lighting is an essential condition for the normal growth and development of Rex rabbits. Generally, two methods are mostly used: artificial lighting and natural lighting. Transparent plastic film can be covered in front of and behind the rabbit house to make full use of sunlight, increase indoor light intake as much as possible, and achieve artificial warming. Rex rabbits can obtain good production performance under 12 hours~16 hours of light per day. Where conditions permit, heating equipment such as radiators, electric heaters, and stoves can also be installed in the house. Strengthen feeding and management. 1. Increase the feed supply. Because winter temperatures are low, rabbits consume more calories, so regardless of size, the daily feeding amount should be 20%~30% higher than usual, and the proportion of high-energy feed should be appropriately increased. In addition, because green fodder is lacking in winter, vitamin deficiency is likely to occur, so efforts should be made to feed some vegetable leaves, carrots, barley sprouts, and tuberous feed, etc., to supplement the lack of vitamins. 2. A small amount of bean dregs or bran should be added to powdered feed, mixed wet with warm water before feeding, and fed little and often to prevent leftover feed from freezing and then being eaten. 3. When using coarse powdered feed, it should be reasonably mixed wet. Coarse powdered feed should be mixed and stirred evenly. Before feeding, mix it wet with warm water at 1:1. Generally, the standard is that when the wet feed is grasped by hand, water seeps between the fingers but does not drip. Mix only what is needed for immediate use, and do not mix too much at one time, so as to maintain the freshness and palatability of the feed. 4. Reasonably match the feed. Rex rabbits are herbivorous animals. Because artificial breeding with only green grass cannot meet the nutritional needs of Rex rabbits, in daily feeding, in addition to regularly feeding some fresh green feed, complete pelleted feed should be prepared in a certain proportion. The advantages of complete pelleted feed are: it does not freeze in winter, does not mold in summer, Rex rabbits love to eat it, and it is comprehensive in nutrition. When mixed feeding, green feed should be matched in multiple types, fresh and clean, and enough compounded concentrate should be supplement-fed. When feeding freely, the content of various nutrients in the mixed feed should be controlled at 10.46 kJ~11.72 kJ digestible energy per kg of feed, 18% crude protein in the early stage, 14% in the later stage, 3%~5% crude fat, 12%~15% crude fiber, 0.5%~0.7% calcium, and 0.3%~0.6% phosphorus. Large-scale raising should preferably use complete compounded pelleted feed. When free-range raising is used, it is advisable to feed coarse feed first, then green feed, and then supplement enough concentrate. Do a good job in rabbit house hygiene and overwintering deworming. In winter, special attention should be paid to doing a good job in the environmental hygiene of the rabbit house, and the rabbit house should be disinfected regularly. Disinfection should use two or more disinfectants in rotation to prevent the development of drug resistance; the rabbit house should be cleaned frequently, feces and dirt should be removed every day, and quicklime should be used to prevent moisture, keeping the house clean, hygienic, and dry, so as to prevent the accumulation of manure and urine, reduce the production of irritant gases such as ammonia and hydrogen sulfide, and prevent respiratory diseases such as rhinitis and pneumonia. In addition, disinfection should be done carefully, and the rabbit house should be kept dry. For the sake of warmth preservation, the rabbit house is more sealed in winter, but poor ventilation leads to an increase in harmful gases such as ammonia, hydrogen sulfide, and sulfur dioxide, which easily induces diseases such as conjunctivitis and rhinitis in Rex rabbits. Therefore, ventilation devices should be installed and automatic ventilation should be strengthened. Doors and windows can be opened every day from 11 a.m. to 2 p.m. to use natural wind for air exchange, and this should be controlled at any time according to the strength of the odor. In order for Rex rabbits to overwinter safely and enhance their physique, before overwintering (in late autumn), drugs such as ivermectin or avermectin and tetramisole should be used, by injection or mixed into feed, to carry out one round of treatment against internal and external parasites for all adult and young rabbits, so as to prevent the invasion and harm of parasitic diseases. Do a good job in winter breeding and mating.

While doing a good job in cold protection and warmth preservation, arranging winter breeding and winter rearing is very important. Its advantages are a high survival rate of kits and a high rate of animals ready for market. Kits grow quickly, have large body size, are robust in constitution, and have high wool yield, making them most suitable to be kept for breeding purposes. As long as cold protection and warmth preservation work is seriously done, better results can still be obtained in winter breeding and mating, especially because the survival rate of kits and young rabbits is high and there are few diseases. In actual production, as long as the warmth preservation work of the kindling box is done well, with dry, soft bedding straw that has strong warmth preservation and good moisture absorption, and the house temperature is kept above 5°C, relatively good winter breeding results can be obtained. In winter, temperatures decrease, pathogenic microorganisms are not active, there are few infectious pathogenic microorganisms, there are few rabbit diseases, and the survival rate of kits is high. As long as a constant-temperature environment is created for Rex rabbits, winter breeding and winter raising are completely possible. Although estrus in breeding does is not very obvious, after all they can come into estrus and can ovulate normally. Therefore, we should seize the opportunity to mate breeding does, and the mating time should be chosen at noon on a sunny, windless, warm day. Mating should grasp the farming proverb well: pink is early, black-purple is late, and bright red is just right. To improve the conception rate, the mating method can use repeated mating or double mating. In addition, 12 days after mating, breeding does should be checked for pregnancy in a timely manner. The method of pregnancy checking is as follows: the person checking pregnancy holds the doe's ears and neck skin with the left hand, fixes the doe on flat ground or a tabletop, with the rabbit's head facing the chest of the person checking pregnancy, and places the right hand in an inverted splayed shape under the doe's abdomen, gently probing and feeling from back to front. Embryos are round spheres and elastic, while fecal pellets are hard spheres and not elastic. Empty does that are not pregnant should be mated again in a timely manner. In addition, the lactation period of winter-bred kits should be longer. Generally, blood mating should not be used, and it is advisable to breed 1 litter~2 litters.