Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
Poult Sci. 2023 May;102(5):102589. doi: 10.1016/j.psj.2023.102589. Epub 2023 Feb 14.
The woody breast (WB) myopathy is an unintended outcome of fast broiler chicken growth and high breast muscle yields. Myodegeneration and fibrosis in the living tissue are results of hypoxia and oxidative stress driven by lack of blood supply to muscle fibers. The study aim was to titrate a vasodilator ingredient, inositol-stabilized arginine silicate (ASI), as a feed additive to improve blood flow and ultimately, breast meat quality. A total of 1,260 male Ross 708 broilers were assigned to: 1) a control basal diet, or the control diet plus increasing ASI: 2) 0.025% ASI, 3) 0.05% ASI, 4) 0.10% ASI, or 5) 0.15% ASI. At d 14, 28, 42, and 49, growth performance was measured on all broilers and serum from 12 broilers/diet was analyzed for creatine kinase and myoglobin presence. On d 42 and 49, 12 broilers/diet were measured for breast width, then left breast fillets were excised, weighed, palpated for WB severity, and visually scored for degree of white striping (WS). At 1 d postmortem, 12 raw fillets/treatment underwent compression force analysis, and at 2d postmortem, the same fillets were analyzed for water-holding capacity. mRNA was isolated from 6 right breasts/diet at both d 42 and 49 for qPCR quantification of myogenic gene expression. Birds fed the lowest dose of 0.025% ASI had a 5-point/3.25% feed conversion ratio reduction compared to birds fed 0.10% ASI over wk 4 to 6 and reduced serum myoglobin at 6-wk of age compared to the control. Breasts from birds fed 0.025% ASI received 42% greater normal WB scores at d 42 compared to control fillets. At d 49, breasts from broilers fed 0.10 and 0.15% ASI received 33% normal WB scores. At d 49, 0.025% AS-fed broiler breasts showed no severe WS. Increased myogenin expression was observed in 0.05 and 0.10% ASI breast samples on d 42 and myoblast determination protein-1 expression was upregulated in breasts from birds fed 0.10% ASI on d 49 compared to the control. Therefore, a dietary inclusion of 0.025, 0.10, or 0.15% ASI was beneficial in reducing WB and WS severity and promoting muscle growth factor gene expression at age of harvest without diminishing bird growth or breast muscle yields.
木质胸（WB）肌病是肉鸡快速生长和高胸肌产量的意外结果。活组织中的肌退化和纤维化是由肌肉纤维供血不足引起的缺氧和氧化应激的结果。本研究的目的是滴定血管扩张剂成分肌醇稳定的精氨酸硅酸盐（ASI）作为饲料添加剂，以改善血流，最终改善鸡胸肉的质量。共有 1260 只雄性罗斯 708 肉鸡被分配到：1）对照基础日粮，或对照日粮加递增 ASI：2）0.025% ASI，3）0.05% ASI，4）0.10% ASI 或 5）0.15% ASI。在第 14、28、42 和 49 天，对所有肉鸡进行生长性能测量，并对 12 只肉鸡/日粮的血清进行肌酸激酶和肌红蛋白存在分析。在第 42 天和第 49 天，测量 12 只肉鸡/日粮的鸡胸宽度，然后切除左侧鸡胸肉，称重，触诊木质胸严重程度，并对白色条纹（WS）的严重程度进行视觉评分。在 1 天死后，12 个生肉片/处理进行压缩力分析，在 2 天死后，对相同的肉片进行保水性分析。在第 42 天和第 49 天，从 6 只右侧胸部/日粮中分离出 mRNA，用于 qPCR 定量分析肌生成基因表达。与 0.10% ASI 相比，第 4 周至第 6 周，喂食最低剂量 0.025% ASI 的鸟类饲料转化率降低了 5 个点/3.25%，并且与对照组相比，6 周龄时血清肌红蛋白降低。与对照肉片相比，喂食 0.025% ASI 的鸟类的第 42 天的正常木质胸评分增加了 42%。在第 49 天，喂食 0.10% 和 0.15% ASI 的肉鸡的正常木质胸评分分别增加了 33%。在第 49 天，喂食 0.025% ASI 的肉鸡的胸部没有严重的 WS。在第 42 天，0.05% 和 0.10% ASI 乳房样本中观察到肌生成素表达增加，在第 49 天，喂食 0.10% ASI 的鸟类的成肌决定蛋白-1 表达上调与对照组相比。因此，日粮中添加 0.025%、0.10% 或 0.15% ASI 可在不降低鸟类生长或胸肌产量的情况下，在收获时降低 WB 和 WS 严重程度并促进肌肉生长因子基因表达。
