National Beef Cattle Industry and Technology System, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
Tin Wah Industrial Co.Ltd, Shimen Industrial Area of Lian Yuan 417100, Hunan Province, China.
J Anim Sci Biotechnol. 2014 Apr 16;5(1):21. doi: 10.1186/2049-1891-5-21. eCollection 2014.
The experiment evaluated the effect of nutrition levels and sex on the growth performance, carcass characteristics and meat quality of F1 Angus × Chinese Xiangxi yellow cattle.
During the background period of 184 d,23 steers and 24 heifers were fed the same ration,then put into a 2 × 2 × 2 factorial arrangement under two levels of - dietary energy (TDN: 70/80% DM), protein (CP: 11.9/14.3% DM) and sex (S: male/female) during the finishing phase of 146 d. The treatments were - (1) high energy/low protein (HELP), (2) high energy/high protein (HEHP), (3) low energy/low protein (LELP) and (4) low energy/high protein (LEHP). Each treatment used 6 steers and 6 heifers, except for HELP- 5 steers and 6 heifers.
Growth rate and final carcass weight were unaffected by dietary energy and protein levels or by sex. Compared with the LE diet group, the HE group had significantly lower dry matter intake (DMI, 6.76 vs. 7.48 kg DM/d), greater chest girth increments (46.1 vs. 36.8 cm), higher carcass fat (19.9 vs.16.3%) and intramuscular fat content (29.9 vs. 22.8% DM). The HE group also had improved yields of top and medium top grade commercial meat cuts (39.9 vs.36.5%). The dressing percentage was higher for the HP group than the LP group (53.4 vs. 54.9%). Steers had a greater length increment (9.0 vs. 8.3 cm), but lower carcass fat content (16.8 vs. 19.4%) than heifers. The meat quality traits (shear force value, drip loss, cooking loss and water holding capacity) were not affected by treatments or sex, averaging 3.14 kg, 2.5, 31.5 and 52.9%, respectively. The nutritive profiles (both fatty and amino acid composition) were not influenced by the energy or protein levels or by sex.
The dietary energy and protein levels and sex significantly influenced the carcass characteristics and chemical composition of meat but not thegrowth performance, meat quality traits and nutritive profiles.
本实验旨在评估营养水平和性别对 F1 安格斯牛×中国湘西黄牛生长性能、胴体特征和肉质的影响。
在 184 天的背景期内，23 头阉牛和 24 头小母牛接受相同的日粮，然后在育肥期的 146 天内，根据能量（TDN：70/80%DM）、蛋白质（CP：11.9/14.3%DM）和性别（S：公/母）两个水平，采用 2×2×2 析因设计进行分组。处理方法如下：（1）高能量/低蛋白（HELP），（2）高能量/高蛋白（HEHP），（3）低能量/低蛋白（LELP）和（4）低能量/高蛋白（LEHP）。除 HELP-外，每个处理组使用 6 头阉牛和 6 头小母牛，其中 HELP-使用 5 头阉牛和 6 头小母牛。
生长速度和最终胴体重不受日粮能量和蛋白质水平或性别影响。与 LE 日粮组相比，HE 日粮组干物质采食量（DMI）显著降低（6.76 比 7.48kgDM/d），胸围增量更大（46.1 比 36.8cm），胴体脂肪（19.9 比 16.3%）和肌肉内脂肪含量（29.9 比 22.8%DM）更高。HE 组还提高了顶级和中级优质商业肉切块的产量（39.9 比 36.5%）。高蛋白（HP）组的屠宰率高于低蛋白（LP）组（53.4 比 54.9%）。阉牛的体长增量（9.0 比 8.3cm）更大，但胴体脂肪含量（16.8 比 19.4%）更低。肉品质特性（剪切力值、滴水损失、蒸煮损失和水分保持能力）不受处理或性别影响，平均值分别为 3.14kg、2.5%、31.5%和 52.9%。能量或蛋白质水平或性别对营养成分（脂肪酸和氨基酸组成）没有影响。
日粮能量和蛋白质水平以及性别显著影响胴体特征和肉质的化学组成，但对生长性能、肉品质特性和营养成分没有影响。
