(1) Selection of male rabbits
As the saying goes, a good female rabbit has a good nest; Good male rabbit, good slope. A female rabbit can only produce dozens of offspring a year, while a male rabbit can produce hundreds or even thousands of offspring a year, so the choice of male rabbits is extremely important, which has a great impact on the whole offspring rabbit group.
To select a male rabbit, the appearance should conform to the variety characteristics and the production direction. Secondly, the breeding male rabbits must be healthy, and the deformity or hypoplasia of reproductive organs is caused by the development of a certain stage in the embryonic period, or by genetic effects, so such male rabbits cannot be used as seeds; Sick people, especially those suffering from infectious diseases, should not be used as seeds, such as partial neck, partial ear, single testis, cryptorchidism, scabbing and erosion of penis or foreskin, and those with hereditary diseases should be eliminated and not used as seeds. Common genetic diseases are as follows:
Naked: only the nose and mouth of the head and the tip of the ear, the back of the four feet and the back of the shoulder blades of the body have a small tuft of hair. It is not easy to distinguish it from normal rabbits at birth, but it is still bare when it is half a month old. Because of the lack of cold-proof coat, its growth and development are hindered.
lack of hair: rabbits only lack the ability to grow villi. When they grow up, they have normal hair on the nose, mouth, limbs and tail, while the whole body has only coarse hair and no villi. This kind of rabbit has weak vitality, and the sperm of the male rabbit has no vitality.
Dwarf rabbit: At birth, its body is almost 1/3 of that of its littermate, and it usually dies within 48 hours after birth. If the proportion of this kind of rabbit is large, the father and mother of this nest of rabbits can no longer be used as seeds.
Ear-dropping rabbit: Under normal circumstances, only two ears of French ram rabbit and one ear of Saibei rabbit droop. Abnormal hanging ears: hanging down and slightly forward on both sides. Of course, except for the rabbit ear drooping caused by the wrong method of catching rabbits, if there is no external factor, it is a hereditary disease.
Cow's eye: "edema eye", which is round and protruding like cow's eye. After about 2 ~ 3 weeks, the eyeball bulges and conjunctivitis occurs. Male rabbits suffering from this disease have decreased sexual desire and fertility. Increasing the level of vitamin A in feed can reduce the incidence of this genetic disease.
paddling feet (forelimbs) and splayed legs (forelimbs and hind legs): refer to the posture of rabbits walking like paddling. It is caused by achondroplasia of hip joint and shoulder joint, and pelvic hypoplasia, dislocation of femur and other deformities also have this symptom. These deformities have been proved to be hereditary, and can also be caused by too slippery cage floor or improper bamboo orientation.
Tremor: It began to appear at the age of 1 ~ 14 days. At first, the whole body trembled slightly, and then it became more and more severe. When the rabbit was asleep, the trembling stopped. At the age of 2 months, the hind limbs were paralyzed, and at the age of 3 months, they were completely paralyzed, and a few people with mild illness survived. When a large proportion of rabbits in the same litter suffer from this disease, both male and female rabbits should be eliminated.
In addition, male rabbits are required to be strong, male, with short neck, broad chest, strong constitution, tight coat, lively temperament, strong appetite and strong sexual desire (female rabbits can be used to test their feelings). It is best to check the semen quality before mating. The testicles are full and symmetrical, the penis is slightly bent, the hair yield is high or the growth rate is fast.
(2) Selection of female rabbits
Like male rabbits of the same species, they are healthy and disease-free, including hereditary diseases and infectious diseases, and their external genitals are clean and inflammation-free.
The female rabbit is slightly longer than the male rabbit, with a slightly long and narrow head, soft lower abdomen, particularly wide pelvic cavity and chest cavity, but not obese. Quiet and gentle personality, the number of nipples should be above 8, arranged neatly and symmetrically, without blind nipples, and the pregnancy rate is high. In the season between December and June, those who refuse to mate for 7 times in a row (once a day), or who are empty-breasted for 2 ~ 3 times in a row, should not be reserved for seed use; There are many litters, and any female rabbit with less than 24 live litters in four consecutive births is not suitable for seed use; High lactation ability, that is, the greater the nest weight at 21 days and 35 days, the better; Motherhood is good, the more you pull your hair before delivery, the better, and the mother rabbit who will give birth and protect her baby in the delivery box is better.
In a word, the selection of breeding female rabbits mainly considers reproductive performance and maternity, that is, newborn litter size, newborn litter weight, 21-day litter weight, weaning litter size, weaning litter weight and the survival rate of young rabbits. Because the reproductive performance is greatly influenced by the environment, we should try our best to choose under the condition of relatively consistent feeding and management environment, or make the final selection after the reproductive performance of three births.