Kuju Agriculture Research Center, Kyushu University, Taketa, Oita 878-0201, Japan.
National Livestock Breeding Center, Nishigo-mura, Fukushima 961-8511, Japan.
J Anim Sci. 2021 Jun 1;99(6). doi: 10.1093/jas/skab123.
The study was conducted to clarify how early high plane of nutrition related to metabolic imprinting affected growth, carcass characteristics, and meat quality of grass-fed Wagyu (Japanese Black cattle). Wagyu steers were allocated randomly into 2 dietary groups: (1) steers fed milk replacer (crude protein 26.0%, crude fat 25.5%; maximum intake 0.6 kg/d) until 3 mo of age and then fed roughage (orchard grass hay) ad libitum from 4 to 10 mo of age (roughage group, RG; n = 11); (2) steers fed milk replacer (maximum intake of 1.8 kg/d) until 3 mo of age and then fed a high-concentrate diet from 4 to 10 mo of age (early high nutrition, EHN; n = 12). After 11 mo of age, all steers were fed roughage ad libitum until 31 mo of age and then slaughtered. Growth performance, carcass traits, longissimus muscle (LM) meat quality and intramuscular fat (IMF) content, plasma insulin-like growth factor I (IGF-I) concentration, and bone mineral density were measured. Body weight was greater in EHN steers (571 kg) than RG steers (520 kg; P < 0.01). Plasma IGF-I levels were higher in EHN steers than in RG steers at 3, 10, and 14 mo of age (P < 0.01, P < 0.005, P < 0.001, respectively); however, plasma IGF-I levels were lower in EHN steers compared with RG steers at 30 mo of age (P < 0.01). The total weight of the muscles and bones of the left half of the carcass was not different between the 2 groups (P = 0.065). Five of the 19 muscles investigated (semimembranosus, P = 0.036; infraspinatus, P = 0.024; supraspinatus, P = 0.0019; serratus ventralis cervicis, P = 0.032; serratus ventralis thoracis, P = 0.027) were heavier in EHN steers. Total fat weight in the left half of the carcass was 30% greater (P = 0.025) in HNE carcasses. Subcutaneous and perirenal fat weights were 53% and 84% greater (P = 0.008, P = 0.002, respectively) in EHN carcasses. The LM IMF content was greater in EHN loins (13.2%) compared with RG loins (9.4%) at 31 mo of age (P = 0.038); however, no differences were found for shear force, tenderness, and cook loss. These results suggested early high-nutrition affected the growth and meat quality of livestock.
该研究旨在阐明早期高水平的营养与代谢印记如何影响草饲和牛（日本黑牛）的生长、胴体特征和肉质。将和牛公牛随机分配到 2 个饮食组：（1）组在 3 月龄前饲喂代乳料（粗蛋白 26.0%，粗脂肪 25.5%；最大摄入量 0.6 千克/天），然后从 4 到 10 月龄自由采食粗饲料（干草）（粗饲料组，RG；n=11）；（2）组在 3 月龄前饲喂代乳料（最大摄入量 1.8 千克/天），然后从 4 到 10 月龄饲喂高浓缩饲料（早期高营养，EHN；n=12）。11 月龄后，所有公牛均自由采食粗饲料，直至 31 月龄，然后屠宰。测量生长性能、胴体性状、背最长肌（LM）肉质和肌内脂肪（IMF）含量、血浆胰岛素样生长因子 I（IGF-I）浓度和骨矿物质密度。EHN 组（571 千克）的体重高于 RG 组（520 千克；P<0.01）。EHN 组在 3、10 和 14 月龄时的血浆 IGF-I 水平高于 RG 组（P<0.01、P<0.005、P<0.001）；然而，在 30 月龄时，EHN 组的血浆 IGF-I 水平低于 RG 组（P<0.01）。2 组左半体肌肉和骨骼的总重量无差异（P=0.065）。在 19 块研究肌肉中，有 5 块肌肉（半膜肌，P=0.036；肩胛下肌，P=0.024；冈上肌，P=0.0019；颈腹侧锯肌，P=0.032；胸肋锯肌，P=0.027）在 EHN 组中更重。EHN 组左半体的总脂肪重量增加 30%（P=0.025）。EHN 组的皮下和肾周脂肪重量分别增加 53%和 84%（P=0.008，P=0.002）。在 31 月龄时，EHN 腰肉的 LM IMF 含量高于 RG 腰肉（13.2%比 9.4%；P=0.038）；然而，剪切力、嫩度和煮失率没有差异。这些结果表明，早期高营养会影响家畜的生长和肉质。
