Abstract: 【Objective】 Inner Mongolian Cashmere Goats (IMCGs) is an excellently breeding which keeps for both cashmere and meat production by long-term natural selection and artificial selection. And IMCGs Distributed in Erlang, Arbas and Alxa. The cashmere yield (CY) and body weight (BW) were important economic traits, which belonged to quantitative traits and were controlled by the microscopic polygene. The genetic parameters of the CY and the BW of IMCGs were evaluated by quantitative genetic methods. The aim of this study was to investigate the effects of different staple length types on the phenotypic characteristics and genetic parameters of CY and BW for Inner Mongolia cashmere goats, so as to provide a theoretical basis for Cashmere goat breeding. 【Method】 In this study, the repetitive data of CY, BW and staple length (SL) of 54 044 Inner Mongolia White Cashmere goats from 1990 to 2014 were collected in a breeding farm. The staple length of IMCGs were divided into three types: short-staple length (≤13cm, SSL), intermediate-staple length (＞13cm and ≤22cm, ISL), and long-staple length (＞22cm, LSL). Excel software was used to analyze the phenotypic of CY and BW. Then, the REG program of SAS 9.2 was employed to calculate the regression coefficient of CY and BW at different staple length that determined the effects of different staple length types on CY and BW. At last, the average information restricted maximum likelihood (AIREML) method in a multivariate animal model on wombat software was used to analyze variance components and estimate the genetic parameters. 【Result】According to the basic statistical analysis of different types of CY and BW, it was found that the average of staple length at LSL increased 6.20 cm and 13.40 cm than that at ISL and SSL, respectively. The CY of was 105.03 g and 59.85 g higher than that at ISL and SSL, respectively. And the BW of LSL was 8.78 kg and 10.06 kg higher than that at ISL and SSL, respectively. According to the basic statistical analysis CY and BW at different staple types, it was found that the CY (721.15 g) was highest and BW (41.98 kg) was highest weight in three types. The variation coefficient of SL and CY decreased with increasing of staple length, but the coefficient of variation of BW increased with the increasing of staple length. Coefficient of variation of CY and BW were above 27%, which indicated that CY and BW had higher potential for improvement. The result showed that the heritabilities of CY were 0.14, 0.22 and 0.33 in SSL, ISL and LSL, respectively. And the heritabilities of CY in SSL belong to the low heritability, while the heritability of CY in ISL and LSL was the moderate heritability. The heritabilities of BW were 0.10, 0.11 and 0.12 in SSL, ISL and LSL, respectively, which belonged to the low heritability. The heritabilities for CY and BW of LSL were highest in three types. The genetic correlation between CY and BW (-0.20 ~ 0.26), CY and SL (-0.11 ~ 0.37) and BW and SL (0.21-0.43) were increased with increasing of staple length. 【Conclusion】The individuals of LSL had the highest phenotypic value of CY and BW, and the heritability of CY and BW were highest, and had the highest genetic correlation among the traits. Therefore, selecting of LSL could accelerate genetic progress for CY and WT and improve the CY and BW, so this study laid the theoretical foundation for the indirect selection in other important economic traits.

Key words: Cashmere goats, different staple types, fleece traits, genetic parameters, indirect selecting