Young bulls of lean continental cattle breeds raised on concentrates achieve high weight gains during fattening but may yield carcasses with low fat cover, which may have negative effects on meat quality. Fattening steers or heifers might be an alternative for these systems, but few studies have analysed in lean breeds the impact of castration of bulls at a similar BW or the performance of females. The aim of the trial was to characterise the growth, carcass and meat quality of bulls, steers and heifers of Pirenaica breed (lean beef breed) fed on concentrates and straw until a common body weight (475 kg). Bulls had greater weight gains than steers and heifers throughout the fattening period (P < 0.001). Bulls had greater plasma IGF-I concentration throughout the fattening period but lower leptin concentration from 400 kg onwards than steers and heifers when compared at the same BW. Regarding metabolites, the concentrations of glucose, beta‑hydroxy‑butyrate, urea and non-esterified fatty acids evolved differently in bulls, steers and heifers. At slaughter, steers and heifers had deposited more fat than bulls without other differences in carcass morphology. Regarding meat quality, meat of heifers had greater lightness and lower yellowness, chroma and hue value than that of bulls and steers. Meat shear force only tended to be different amongst sexes after 14 days of ageing (P < 0.10). Heifers had greater intramuscular fat content than steers and bulls. Total saturated fatty acids were similar amongst groups but monounsaturated fatty acids proportion was greatest in heifers, intermediate in steers and lowest in bulls. Polyunsaturated fatty acid proportion was greater in bulls than in steers and heifers. Only minor effects of sex were detected by the sensory panel, with more desirable flavours and higher tenderness in heifers. Therefore, despite the faster growth of entire bulls, fattening steers and especially heifers can lead to improved fat-related meat quality traits in lean breeds.

在浓缩过程中饲养的精瘦大陆牛品种的幼小公牛在增肥过程中可实现较高的增重，但cover体的脂肪覆盖率较低，这可能对肉质产生负面影响。育肥的公牛或小母牛可能是这些系统的替代方法，但是很少有研究对瘦肉品种的公猪去势对类似体重的影响或对雌性的影响进行分析。该试验的目的是表征以精矿和稻草为食的直到公重（475 kg）的比雷纳尼加牛（瘦牛肉）公牛，s牛和小母牛的生长，growth体和肉品质。在育肥期内，公牛的体重增加量大于公牛和小母牛的体重增加（P <0.001）。在相同的体重下，公牛在整个育肥期内的血浆IGF-I浓度较高，但从400 kg开始的瘦素浓度低于公牛和小母牛。关于代谢物，公牛，公牛和小母牛的葡萄糖，β-羟基丁酸酯，尿素和非酯化脂肪酸的浓度变化不同。屠宰时，ste牛和小母牛的fat体脂肪多于公牛，without体形态没有其他差异。关于肉的质量，小母牛的肉比公牛和公牛的肉具有更高的亮度，更低的黄度，色度和色调值。老化14天后，性别之间的切肉力仅趋于不同（P <0.10）。小母牛的肌肉内脂肪含量高于公牛和公牛。各组之间的总饱和脂肪酸相似，但小母牛的单不饱和脂肪酸比例最大，公牛中等，而公牛最低。公牛的多不饱和脂肪酸比例大于公牛和小母牛。感官小组仅检测到轻微的性别影响，在小母牛中具有更理想的风味和更高的嫩度。因此，尽管整个公牛的生长速度更快，但育肥的ers牛，尤其是小母牛，可以改善瘦肉品种中与脂肪相关的肉质性状。