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    家兔的選配的幾種類型及特點

    發(fā)布日期:2017-06-22 來源:http://www.tunjie.cn 發(fā)布人:admin

    表型選配

    Phenotypic selection

    表型選配又稱為品質(zhì)選配,是根據(jù)外表性狀或品質(zhì)選擇配公母兔的一種方法。它又可以分為同型選配和異型選配兩種。

    Phenotypic selection, also known as quality matching, is a method of selecting a female rabbit based on apparent traits or qualities. It can be divided into two types: the same type selection and the odd type selection.

    同型選配

    positive assortative mating

    同型選配就是選擇性狀相同、性能表現(xiàn)一致的公母兔配種,以期獲得相似的后代。選配雙方愈相似,愈有可能將共同的品質(zhì)傳給后代。其目的在于使這些性狀在后代中得到保持和鞏固,也有可能把個體品質(zhì)轉(zhuǎn)化為群體的品質(zhì),使個體數(shù)量增加。例如,為了提高兔群的生長速度,可選擇生長速度快的公母兔交配,使它們的后代保持這一特性。因此,這種選配方法適用于公母兔之間。

    The same type selection is to select the same nature and performance of the same male and female rabbit breeding, in order to obtain similar good offspring. The more similar they are, the more likely it is to pass on the same good qualities to their offspring. The aim is to maintain and consolidate these fine traits in future generations, and to transform individual qualities into group qualities and to increase the number of good individuals. For example, in order to increase the growth rate of rabbit populations, male female rabbits with fast growth rate can be chosen to mate with their offspring to maintain this fine trait. Therefore, this method is suitable for excellent male and female rabbits.

    異型選配

    negative assortative mating

    異型選配可分為兩種情況,一種是選擇有不同優(yōu)異性狀的公母兔交配,以期將兩個性狀結合在一起,從而獲得兼有雙親不同優(yōu)點的后代。例如,選擇兔毛生長速度快和兔毛密度大的公母兔交配,從而使后代兔毛生長速度快和兔毛密度大,更終使后代產(chǎn)毛量提高。

    There are two types of special selection. One is to choose the male and female rabbits with different excellent traits, in order to combine the two characters, so as to obtain offspring with different parents' advantages. For example, choose the hair growth speed and rabbit density of the male and female rabbits mated to offspring hair growth speed and hair density, the offspring of wool yield increase.

    另一種情況是選擇同一性狀優(yōu)劣程度不同的公母兔交配,即所謂以優(yōu)改劣,以性狀糾正不良性狀。例如在本品種中,有些肉用種兔繁殖性能較好,只是生長速度較慢,即可選擇一只生長速度快的肉用公兔與其相配,使后代不僅繁殖力高而且生長速度也較快。實踐證明,這是一種可以用來改良許多性狀的行之有效的選配方法。

    Another situation is that the male and female rabbits of the same character are chosen to mate with each other, which is called "superior to bad", and good characters are used to correct the bad characters. For example, in this species, some better reproductive performance of meat rabbits, but slower growth rate, you can choose one of the fastest growing meat rabbits matched, so the offspring not only high fecundity and growth rate is faster. Practice has proved that this is a kind of effective selection method that can be used to improve many characters.

    年齡選配

    Age matching

    年齡選配,就是根據(jù)公母兔之間的年齡進行選配的一種方法。家兔的年齡明顯地影響其繁殖性能。一般青年種兔的繁殖能力較差,隨著年齡的增長繁殖性能逐漸提高,1歲~2歲繁殖性能逐漸達到高峰,2歲半以后逐漸下降。在我國飼養(yǎng)管理條件下,種兔一般使用到3歲~4歲。所以在養(yǎng)兔生產(chǎn)實踐中,通常主張壯年公兔配壯年母兔,采用這種選配方式效果較好。0..

    Age selection is a method of selecting matches according to the age between the male and female rabbits. The age of the rabbit significantly affected its reproductive performance. The general young rabbit breeding ability is poor, with a gradual increase in growth performance of age, 1 years old to 2 years old reproductive performance gradually reached the peak, and decreased gradually after 2 and a half years old. In our country, feeding and management conditions, the general use of rabbits at the age of 3 to 4 years old. Therefore, in the practice of raising rabbits, it is generally advocated that the male rabbits should be matched with the young rabbits. 0..

     

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