The objective of this study was to estimate and describe phenotypic traits for carcass and meat quality in Nellore cattle belonging to the breeding programs. Data from 718 Nellore animals participated in the Delta Gen, CRV Paint and Nelore Qualitas breeding programs were used. Meat quality traits were measured and the data were analyzed. The following means and standard deviations of the meat quality traits were obtained: shear force (SF = 5.7 ± 1.3 kg), myofibril fragmentation index (MFI = 32.0 ± 15.3), cooking loss (CL = 27.7 ± 3.1%), intramuscular lipid content (ILC = 0.9 ± 0.5%), backfat thickness (BFT = 4.2 ± 1.4 mm), marbling score (MS = 2.6 ± 0.36), rib eye area (REA = 72.8 ± 7.35 cm²) and instrumental color (lightness (L* = 27.9 ± 2.7), redness (a* = 12.4 ± 1.86), yellowness (b* = 5.5 ± 1.0)). Significant phenotypic correlations were observed between BFT and MS (0.2314), and between MS and ILC (0.1308). A negative and significant correlation was found between SF and MFI (-0.5525); however, the correlation with MFI was low in animals with SF values ​​higher than 6 kg. In principal component analysis (PCA), the first four eigenvalues of the matrix of direct additive genetic variance explained 61.26% of the total additive genetic variance in the meat quality traits. The most important meat quality traits in PC1 were a*, b* and CL. PC2 was characterized by MFI and color (a* and b*), PC3 by MS, BFT and L* and PC4 by ILC, L* and b*. Furthermore, BFT was positively associated with MS, SF and CL, and SF was negatively associated with MFI. The present study suggests that muscle growth and backfat thickness were satisfactory; however, intramuscular fat deposition and meat tenderness still require more attention from the breeding programs.

这项研究的目的是评估和描述属于育种计划的内洛尔牛cattle体和肉质的表型性状。来自718个Nellore动物的数据参与了Delta Gen，CRV Paint和Nelore Qualitas繁殖计划。测量肉质性状并分析数据。获得了以下肉品质性状的平均值和标准偏差：剪切力（SF = 5.7±1.3 kg），肌原纤维断裂指数（MFI = 32.0±15.3），蒸煮损失（CL = 27.7±3.1％），肌内脂质含量（ILC = 0.9±0.5％），后脂肪厚度（BFT = 4.2±1.4 mm），大理石花纹得分（MS = 2.6±0.36），肋眼区域（REA = 72.8±7.35 cm ²）和仪器颜色（亮度（L * = 27.9±2.7），红色（a * = 12.4±1.86），黄色（b * = 5.5±1.0））。在BFT和MS之间（0.2314）以及MS和ILC之间（0.1308）观察到显着的表型相关性。SF和MFI之间存在负相关和显着相关性（-0.5525）；但是，SF值高于6 kg的动物与MFI的相关性较低。在主成分分析（PCA）中，直接加性遗传方差矩阵的前四个特征值解释了肉品质性状中总加性遗传方差的61.26％。PC1中最重要的肉质特征是a *，b *和CL。PC2的特征是MFI和颜色（a *和b *），PC3的特征是MS，BFT和L *，PC4的特征是ILC，L *和b *。此外，BFT与MS，SF和CL呈正相关，SF与MFI呈负相关。本研究表明，肌肉生长和后脂肪厚度令人满意。但是，肌内脂肪沉积和肉嫩感仍然需要繁殖计划的更多关注。