National Livestock Breeding Center, Nishigo, Fukushima, Japan.
Tottori Prefectural Livestock Research Center, Kotoura, Tottori, Japan.
Anim Sci J. 2021 Jan-Dec;92(1):e13504. doi: 10.1111/asj.13504.
The objective of this study was to estimate variance components related to imprinting for carcass traits and physiochemical characteristics in Japanese Black cattle. The carcass records obtained from 4,220 Japanese Black feedlot cattle included carcass weight (CW), rib eye area (REA), rib thickness, subcutaneous fat thickness, and beef marbling score (BMS), and the physiochemical characteristics were fat, moisture, glycogen per proportion of moisture content, oleic acid, and monounsaturated fatty acids (MUFA). To detect gametic effects, an imprinting model was fitted. High additive heritabilities were estimated for all traits (from 0.516 for glycogen to 0.853 for fat) and were reduced in Mendelian heritability. The range of the differences was from 0.002 (CW) to 0.331 (fat and moisture), and the reductions were due to their imprinting variances. The ratio of the imprinting variance to the total additive genetic variance for REA (0.374), BMS (0.291), fat (0.387), moisture (0.388), and MUFA (0.337) were large (p < 0.05). These imprinting variances were due to the maternal contribution and suggested the existence of maternally expressed genomic imprinting effects on the traits in Japanese Black cattle. Therefore, maternal gametic effects should be considered in breeding programs for Japanese Black cattle.
本研究旨在估计日本黑牛胴体性状和理化特性的印迹方差分量。从 4220 头日本黑肥牛的胴体记录中获得了胴体重量（CW）、眼肌面积（REA）、肋骨厚度、皮下脂肪厚度和牛肉大理石花纹评分（BMS），以及理化特性包括脂肪、水分、水分含量比例的糖原、油酸和单不饱和脂肪酸（MUFA）。为了检测配子效应，拟合了印迹模型。所有性状的加性遗传力均较高（从糖原的 0.516 到脂肪的 0.853），且在孟德尔遗传力中降低。差异范围从 0.002（CW）到 0.331（脂肪和水分），减少归因于印迹方差。REA（0.374）、BMS（0.291）、脂肪（0.387）、水分（0.388）和 MUFA（0.337）的印迹方差与总加性遗传方差的比值较大（p<0.05）。这些印迹方差归因于母本贡献，表明日本黑牛的这些性状存在母系表达的基因组印迹效应。因此，在日本黑牛的育种计划中应考虑母本配子效应。
