Zhang Huaiyong, Zeng Quifeng, Bai Shiping, Wang Jianping, Ding Xuemei, Xuan Yue, Su Zhuowei, Michiels Joris, Zhang Keying
Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China, Ministry of Education, Sichuan Agricultural University, Chengdu, 611130, China.
College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450002, China.
Anim Nutr. 2021 Nov 2;9:49-59. doi: 10.1016/j.aninu.2021.10.005. eCollection 2022 Jun.
To define the relationship between dietary nutrient density, calcium (Ca), and meat quality in meat ducks. A total of 288 male Cherry Valley SM3 medium ducklings were fed a common standard starter diet until d 14. At 15 d of age, ducks were randomly divided into 2 treatment groups and fed either a conventional diet or a low nutrient density (LND) diet. Compared with the conventional diet, the energy was reduced in the LND diet by 8.6% and 16.8% in grower (15 to 35 d) and finisher (36 to 56 d) phases, respectively, while other essential nutrients were kept proportionate to energy. The LND diet decreased the shear force ( < 0.05) and increased the lightness values of the pectoralis muscle when compared to the conventional diet, suggesting that LND diet exerted a beneficial role in meat quality. Subsequently, the effects of grated Ca in the LND diet on meat quality of pectoralis muscle were evaluated. A total of 576 male ducklings were fed a common starter diet until d 14, followed by feeding 4 LND diets with 0.5%, 0.7%, 0.9%, and 1.1% Ca. The results show that LND diets with 0.7% or more Ca decreased the shear force of pectoralis major muscle in 42-d-old meat ducks ( < 0.05). To explore the mechanism underlying Ca and tenderness, data from birds fed either 0.5% or 1.1% Ca in the LND diet indicated that birds fed 1.1% Ca exhibited lower shear force, upregulated expression, and higher calpains activity compared to those fed the LND diet with 0.5% Ca ( < 0.05). Moreover, the 1.1% Ca LND diet induced a higher myocyte apoptosis ( = 0.06) and upregulated mRNA expression of ( = 0.07) in breast muscle. Our data suggest that LND diets with 0.9% or 1.1% Ca had a positive role in the tenderness of breast meat, particularly the enhancing effect of 1.1% Ca LND diet on tenderness seems to be associated with proteolytic changes of myofibrillar proteins and myocyte apoptosis in meat ducks.
为了确定肉鸭日粮营养密度、钙（Ca）与肉质之间的关系。总共288只雄性樱桃谷SM3中雏鸭饲喂普通标准开食料至14日龄。在15日龄时，将鸭子随机分为2个处理组，分别饲喂常规日粮或低营养密度（LND）日粮。与常规日粮相比，LND日粮在生长育肥期（15至35日龄）和育肥期（36至56日龄）的能量分别降低了8.6%和16.8%，而其他必需营养素与能量保持比例。与常规日粮相比，LND日粮降低了胸肌的剪切力（P<0.05）并提高了亮度值，表明LND日粮对肉质发挥了有益作用。随后，评估了LND日粮中添加磨碎钙对胸肌肉质的影响。总共576只雄性雏鸭饲喂普通开食料至14日龄，随后饲喂4种钙含量分别为0.5%、0.7%、0.9%和1.1%的LND日粮。结果表明，钙含量为0.7%或更高的LND日粮降低了42日龄肉鸭胸大肌的剪切力（P<0.05）。为了探究钙与嫩度的潜在机制，来自饲喂LND日粮中钙含量为0.5%或1.1%的鸭子的数据表明，与饲喂钙含量为0.5%的LND日粮的鸭子相比，饲喂钙含量为1.1%的鸭子表现出更低的剪切力、上调的钙蛋白酶表达和更高的钙蛋白酶活性（P<0.05）。此外，钙含量为1.1%的LND日粮诱导了更高程度的肌细胞凋亡（P=0.06）并上调了胸肌中钙蛋白酶的mRNA表达（P=0.07）。我们的数据表明，钙含量为0.9%或1.1%的LND日粮对胸肉嫩度具有积极作用，特别是钙含量为1.1%的LND日粮对嫩度的增强作用似乎与肉鸭肌原纤维蛋白的蛋白水解变化和肌细胞凋亡有关。
