It is a very important approach to conserve the improved goat breeds and to develop goat production in our country through understanding genetic mechanism of prolificacy and increasing fertility of goats. Polymorphism of GH, IGF-Ⅰand IGF-Ⅱgenes and their relationships with prolificacy of Lezhi Black goat were analyzed in this study. In addition, cloning and mRNA expression levels of GH, IGF-Ⅰand IGF-Ⅱgenes were carried out in Lezhi Black Goat and Tibetan Goat in order to understand prolific mechanism of Lez...