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利用B超测定的447只特克塞尔羊与哈萨克羊杂交获得的F2代6月龄羔羊的背膘厚度、眼肌深度和眼肌面积的表型数据和该群体的育种资料，系统分析影响6月龄羔羊上述性状的非遗传因素，为绵羊生产和选育提供更加科学的指导。应用SPSS22.0的GLM程序分析了出生类型、性别、母羊年龄、群别等多种非遗传因素对6月龄羔羊上述肉用性状的影响。出生类型、性别分别对6月龄羔羊背膘厚度有极显著影响（P<0.01），单胎羔羊背膘厚度极显著高于双胎羔羊,公羔的背膘厚度极显著高于母羔。母羊年龄、群别对6月龄羔羊背膘厚度没有显著影响（P>0.05）；性别对6月龄羔羊眼肌深度有显著影响（P<0.05），对6月龄羔羊眼肌面积有极显著影响（P<0.01），公羔的眼肌深度与眼肌面积显著高于母羔。母羊年龄对6月龄羔羊眼肌深度和眼肌面积均有极显著影响（P<0.01），年龄3岁及3岁以上母羊生产的羔羊眼肌深度和眼肌面积显著高于母羊年龄3岁以下生产的羔羊。母羊年龄3岁以上与3岁相比，二者所产羔羊的眼肌深度和眼肌面积差异不显著。出生类型、群别对6月龄羔羊眼肌深度和眼肌面积无显著影响（P>0.05）。6月龄羔羊的背膘厚度、眼肌深度和眼肌面积三个肉用性状受到羔羊出生类型、性别及其生产母羊年龄的显著影响，在绵羊饲养管理和选种选育时应考虑它们对6月龄羔羊上述性状的影响，提高对上述肉用性状选育及遗传评估准确性。

Using the phenotypic data of backfat thickness, eye muscle depth and eye muscle area of F2 generation 6-month old lambs obtained from the cross between 447 Texel sheep and Kazak sheep measured by B-ultrasound, and the non heritable factors affecting the above traits of 6-month old lambs were analyzed systematically, so as to provide more scientific guidance for sheep production and breeding. The GLM program of SPSS22.0 was used to analyze the effects of various non-genetic factors, such as birth type,gender, ewe age and herd type on the above meat traits of 6-month old lambs. Birth type and gender had significant effects on the backfat thickness of 6-month old lambs(P <0.01), and the backfat thickness of single-born lambs was significantly higher than that of twin lambs, and backfat thickness of male lambs was significantly higher than that of female lambs. There was no significant effect of ewe age and group on backfat thickness of 6-month old lambs(P>0.05);There was a significant effect of gender on eye muscle depth of 6-month old lambs(P<0.05) and a extremely significant effect on eye muscle area of 6-month old lambs(P<0.01). The eye muscle depth and eye muscle area of male lambs were highly larger than those of female lambs. The ewes age had extremely significant effect(P<0.01) on eye muscle depth and area in 6-month old lambs, and eye muscle depth and area in lambs produced by ewes aged 3 years and older were significantly higher than those produced by ewes aged less than 3 years. However, there was no significant difference in eye muscle depth and area between the lambs aged 3 years old and those aged over 3 years old..Birth type and group had no significant effect on eye muscle depth and area in 6-month old lambs(P>0.05). The three meat traits of backfat thickness, eye muscle depth and eye muscle area in 6-month old lambs were significantly influenced by the lamb birth type, gender, and the age of ewes. Therefore, their effects on the above traits of 6-month old lambs should be considered in sheep feeding management and breeding selection, so as to improve the selection and genetic assessment accuracy of the above traits for meat use.