Departamento de Zootecnia, Universidade Do Estado de Santa Catarina, (UDESC, Rua Beloni Trombeta Zanin, 680, Chapecó, SC, CEP: 89815-630, Brazil.
Trop Anim Health Prod. 2021 Oct 22;53(6):521. doi: 10.1007/s11250-021-02965-z.
Beef cattle production has a large variety of systems with different performance and technology levels. This study compared young Angus steers carcass and meat quality traits of high growth potential early-finished animals fed exclusively on pasture with low growth potential late-finished animals. Besides the grazed forage, the low growth potential group received corn grain at 0.8% of their body weight right after the slaughtering of the first group. Following weaning, the 20 steers grazed pastures composed of oat, ryegrass, and clovers. At winter's onset, animals were moved to native pastures improved with fescue and clovers. The supplemented period of late steers began when the first group of ten early-finished animals reached the requirements for slaughter. Supplementation ended when the animals got the slaughter requirements. The high growth potential steers showed a ribeye area (P < 0.0001) and a Longissimus muscle width highly significantly (P < 0.0001) superior to the low growth group. However, corn-supplemented animals showed better dressing percentage (P < 0.0001), subcutaneous fat thickness (P < 0.0001), marbling (P < 0.0001), and muscle (P = 0.0033) scores, but lower shear force (P = 0.0001). The finishing system did impact fat lightness (L*; P = 0.0234) at the slaughter time. Grass-fed animals showed higher red-green color parameter (a*) values than corn supplemented on fat at 24 h (P = 0.0439) but lower hue angle (P = 0.0418). The consumer panel showed better results for tenderness and general acceptability for supplemented animals beef compared to grass-fed. The supplementation resulted in a higher carcass standardization. It also provided higher PUFA: MUFA and n-6: n-3 ratios, and a higher amount of n-3. Supplemental corn grain did not have adverse effects upon the beneficial effects to human health of the grass-fed beef.
肉牛生产有多种系统,具有不同的性能和技术水平。本研究比较了高生长潜力的早期育肥动物和低生长潜力的晚期育肥动物的安格斯犊牛胴体和肉质特性。除放牧的饲草外,低生长潜力组在第一批动物屠宰后立即按体重的 0.8%给牛喂玉米。断奶后,20 头育肥牛放牧于燕麦、黑麦草和三叶草组成的牧场上。冬季开始时,动物被转移到用羊茅和三叶草改良的本地牧场上。当第一批 10 头早期育肥牛达到屠宰要求时,开始对后期育肥牛进行补充饲养。当动物达到屠宰要求时,补充饲养结束。高生长潜力的育肥牛的肋眼面积(P<0.0001)和腰最长肌宽度(P<0.0001)显著高于低生长潜力组。然而,补充玉米的动物具有更高的屠宰率(P<0.0001)、皮下脂肪厚度(P<0.0001)、大理石花纹(P<0.0001)和肌肉评分(P=0.0033),但剪切力较低(P=0.0001)。育肥系统确实会影响屠宰时脂肪的亮度(L*;P=0.0234)。草饲动物的脂肪在 24 小时时的红-绿颜色参数(a*)值高于补充玉米的动物(P=0.0439),但色调角较低(P=0.0418)。消费者小组认为补充玉米的动物的嫩度和总体可接受性优于草饲动物。补充玉米提高了胴体的标准化程度。它还提供了更高的多不饱和脂肪酸:单不饱和脂肪酸和 n-6:n-3 比例,以及更多的 n-3。补充玉米对草饲牛肉对人类健康的有益影响没有不良影响。