de Carvalho Isabella Silva, Lázaro Sirlene Fernandes, Carrara Eula Regina, de Souza Matheus Rodrigues, Tonhati Humberto
Faculdade de Ciências Agrárias e Veterinárias, UNESP, Jaboticabal, Brazil.
Centre for Genetic Improvement of Livestock, Department of Animal Biosciences, University of Guelph, Guelph, Ontario, Canada.
J Anim Breed Genet. 2025 Nov;142(6):718-731. doi: 10.1111/jbg.12941. Epub 2025 May 8.
Traits related to growth, carcass quality and stayability are key components in enhancing the profitability and sustainability of Nelore cattle production systems. This study aimed to estimate heritabilities and genetic and environmental correlations for these traits using a Bayesian approach. Data from 94,703 females were analysed for weights at 210, 365 and 450 days of age (W210, W365 and W450), loin eye area (LEA), subcutaneous fat thickness in the loin (LFT) and rump (REFT) and stayability at 48, 54 and 72 months (STAY48, STAY54 and STAY72). Heritability estimates (± standard error) were 0.14 ± 0.03 for LEA, 0.20 ± 0.03 for LFT, 0.43 for REFT, 0.12 ± 0.02 for STAY54, and 0.18 ± 0.02 for STAY72. Moderate heritabilities for W210, W365, W450, LFT and REFT indicate a substantial additive genetic component, whereas lower estimates for LEA and stayability suggest a predominant influence of environmental factors. Genetic trends were generally positive but moderate: 0.14 kg/generation (W210), 1.40 kg/generation (W365), 1.77 kg/generation (W450), 0.016 cm/generation (LEA) and 0.0081 months/generation (STAY72). In contrast, STAY48 showed a slightly negative trend (-0.0073 months/generation). Direct selection for W450 yielded a genetic gain of 9.837 kg, whereas indirect selection via correlated traits resulted in gains ranging from 0.125 to 9.272 kg. These findings highlight the relevance of environmental effects on traits with low heritability, such as LEA and stayability, and reinforce the effectiveness of selection for weight-related traits due to their moderate heritability and favourable genetic trends.
与生长、胴体品质和持续力相关的性状是提高内洛尔牛生产系统盈利能力和可持续性的关键组成部分。本研究旨在使用贝叶斯方法估计这些性状的遗传力以及遗传和环境相关性。分析了来自94,703头母牛的数据，包括210日龄、365日龄和450日龄时的体重（W210、W365和W450）、眼肌面积（LEA）、腰部皮下脂肪厚度（LFT）和臀部皮下脂肪厚度（REFT），以及48月龄、54月龄和72月龄时的持续力（STAY48、STAY54和STAY72）。遗传力估计值（±标准误）分别为：LEA为0.14±0.03，LFT为0.20±0.03，REFT为0.43，STAY54为0.12±0.02，STAY72为0.18±0.02。W210、W365、W450、LFT和REFT的中等遗传力表明存在大量加性遗传成分，而LEA和持续力的较低估计值表明环境因素的主要影响。遗传趋势总体呈正向但中等：0.14千克/代（W210），1.40千克/代（W365），1.77千克/代（W450），0.016厘米/代（LEA），0.0081月龄/代（STAY72）。相比之下，STAY48呈现出略微负向的趋势（-0.0073月龄/代）。对W450进行直接选择产生了9.837千克的遗传进展，而通过相关性状进行间接选择产生的进展范围为0.125至9.272千克。这些发现突出了环境效应对于低遗传力性状（如LEA和持续力）的相关性，并强化了由于体重相关性状具有中等遗传力和有利遗传趋势而进行选择的有效性。
