This study was conducted to evaluate the effects of diets supplemented with nucleotides and guanidinoacetic acid (GAA) on broiler chickens growth performance, blood metabolites, leukocyte differential count, mitotic activity of satellite cells, carcass yield, meat quality, chemical analysis of breast muscle, incidence of breast myopathies, and skin lesions from 0 to 42d. A total of 600 one-day-old male broiler chickens were randomly distributed among three treatments with eight replicates and 25 broiler chickens per pen. Treatments consisted of a control diet (CD), the CD + one g/kg of nucleotides (fed from 0 to 28 d, afterwards broilers were fed CD) and the CD + 0.6 g/kg of GAA (fed from 0 to 42 d). On 10 d, broiler chickens fed with GAA had an improved feed conversion ratio (FCR) (P < 0.05), increased BWG (P < 0.05), and plasmatic concentration of creatine kinase (P < 0.05) when compared to broiler chickens fed the CD. On 28 d, breast meat of broiler chickens fed with GAA showed a reduction in fat content, compared to the nucleotides. Broiler chickens fed with GAA had a reduction in dermatosis and incidence of moderate and average scores of wooden breast (WB) scoring, besides the proportions of severe and average scores of white stripping (WS) scoring at 42 d, compared to broiler chickens fed diets supplemented with nucleotides. In conclusion, supplementation of nucleotides increases the incidence of breast myopathies, without affecting other variables and GAA supplementation improves broiler chickens growth performance compared to control group from 0 to 10 d and reduced the severity of myopathies and the occurrence of dermatosis at 42 d.

本研究旨在评估添加核苷酸和胍基乙酸 (GAA) 的日粮对肉鸡生长性能、血液代谢物、白细胞分类计数、卫星细胞有丝分裂活性、胴体产量、肉质、胸肌化学分析、 0 至 42 天乳房肌病和皮肤病变的发生率。600只1日龄雄性肉鸡随机分布在3个处理中，每圈8个重复，每圈25只肉鸡。处理包括对照日粮 (CD)、CD + 1 g/kg 核苷酸（从 0 到 28 天喂食，之后肉鸡喂食 CD）和 CD + 0.6 g/kg GAA（从 0 到 42 天喂食） ）。在第 10 天，饲喂 GAA 的肉鸡的饲料转化率（FCR）提高（P < 0.05），BWG 增加（P < 0.05) 和血浆肌酸激酶浓度 ( P< 0.05) 与喂食 CD 的肉鸡相比。在第 28 天，与核苷酸相比，用 GAA 喂养的肉鸡的胸肉显示脂肪含量降低。与饲喂日粮的肉鸡相比，饲喂 GAA 的肉鸡皮肤病和木胸 (WB) 评分中度和平均评分的发生率降低，此外在 42 天时白剥皮 (WS) 评分的严重和平均评分比例也有所降低补充核苷酸。总之，核苷酸的添加增加了乳腺肌病的发病率，而不影响其他变量，与对照组相比，GAA 的添加提高了肉鸡在 0 至 10 天的生长性能，并降低了肌病的严重程度和 42 天的皮肤病的发生率。