Torrecilhas Juliana Akamine, Pereira Guilherme Luis, Vito Elias San, Fiorentini Giovani, Ramirez-Zamudio Germán Darío, Fonseca Larissa Simielli, Torres Rodrigo de Nazaré Santos, Simioni Tiago Adriano, Duarte Juliana Messana, Machado Neto Otavio Rodrigues, Curi Rogério Abdallah, Chardulo Luis Artur Loyola, Baldassini Welder Angelo, Berchielli Telma Teresinha
School of Veterinary e Animal Science (FMVZ), São Paulo State University (Unesp), Jaboticabal 14884-900, SP, Brazil.
Confina Beef Cattle Consulting, Sinop 78555-603, MT, Brazil.
Metabolites. 2023 Sep 28;13(10):1042. doi: 10.3390/metabo13101042.
The objective was to evaluate the supplementation strategy's effect on beef cattle during the growing phase and two systems during the finishing phase. One hundred and twenty young bulls were randomly divided in a 2 × 2 factorial design to receive either mineral (ad libitum) or protein + energy (3 g/kg body weight (BW)/day) during the growing phase and pasture plus concentrate supplementation (20 g/kg BW/day) or feedlot (25:75% corn silage:concentrate) during the finishing phase. Feedlot-fed bulls had meat (-LT) with a higher content of lipids and saturated and monounsaturated fatty acids and a greater upregulation of and than animals that fed on pasture ( < 0.05). On the other hand, pasture-fed bulls had meat with a higher content of α-linoleic acid, linolenic acid, and n6 and a greater n6:n3 ratio compared to the feedlot-fed group ( < 0.05). In addition, meat from pasture-fed bulls during the finishing phase had 17.6% more isocitrate dehydrogenase enzyme concentration than the feedlot group ( = 0.02). Mineral-fed and pasture-finished bulls showed down-regulation of ( < 0.05), while the bulls fed protein + energy and finished in the feedlot had higher expression ( ≤ 0.013). In conclusion, mineral or protein + energy supplementation in the growing does not affect the fatty acid composition of intramuscular fat of LT muscle. In the finishing phase, feeding bulls in the feedlot upregulates the lipogenic genes and consequently improves the intramuscular fat content in the meat.
目的是评估补充策略对生长阶段肉牛以及育肥阶段两种饲养系统的影响。120头年轻公牛被随机分为2×2析因设计，在生长阶段接受矿物质（自由采食）或蛋白质+能量（3克/千克体重/天），在育肥阶段接受牧场加精料补充（20克/千克体重/天）或饲养场（25:75%玉米青贮:精料）。与在牧场饲养的动物相比，饲养场饲养的公牛的肉（-LT）中脂质、饱和脂肪酸和单不饱和脂肪酸含量更高， 和 的上调幅度更大（P<0.05）。另一方面，与饲养场饲养的组相比，牧场饲养的公牛的肉中α-亚麻酸、亚麻酸和n6含量更高，n6:n3比值更大（P<0.05）。此外，育肥阶段牧场饲养的公牛的肉中异柠檬酸脱氢酶浓度比饲养场组高17.6%（P = 0.02）。矿物质饲养且在牧场育肥的公牛表现出 的下调（P<0.05），而蛋白质+能量饲养且在饲养场育肥的公牛 表达更高（P≤0.013）。总之，生长阶段补充矿物质或蛋白质+能量不会影响LT肌肉肌内脂肪的脂肪酸组成。在育肥阶段，在饲养场饲养公牛会上调脂肪生成基因，从而提高肉中的肌内脂肪含量。
