本研究旨在探讨日粮中添加不同水平迷迭香提取物(RE)对其生长性能的影响。肉质,血清生物化学,抗氧化能力,樱桃谷肉鸭的免疫能力。本研究共选择525只健康的樱桃谷雌性肉鸭在1日龄。鸭子随机分为5个处理,每个处理7个重复,每个复制品有15只鸭子。将所有重复随机分配到处理。该研究被设计为剂量反应实验。治疗1(CON)饲喂基础饮食,和处理2至5(RE250,RE500,RE750,RE1000)饲喂补充有250,500,750和1,000g/tRE的基础饮食,分别。整个实验持续42天,早期(1-21d)和晚期(22-42d)。结果表明,在22~42d,饲喂超过500g/tRE的鸭子的饲料增益比明显低于CON中的鸭子(P=0.006)。此外,与CON相比,RE750中的鸭子腿部肌肉的L*和a*显着降低(P<0.05)。此外,饲喂250至750g/tRE的鸭子的血清总蛋白水平明显低于CON(P=0.005)。RE250和RE750中的鸭子具有显著较低的白蛋白,总胆固醇,高密度脂蛋白胆固醇,血清低密度脂蛋白胆固醇水平与CON和RE1000相比(P<0.05),白蛋白之间存在显著的二次关系,总胆固醇,高密度脂蛋白胆固醇,低密度脂蛋白胆固醇和饲粮RE水平(P<0.05)。此外,与CON和RE1000相比,饲喂500至750g/tRE的鸭子血清中白细胞介素2的水平明显更高(P=0.003)。与CON和RE1000相比,RE250和RE750中的鸭血清中的免疫球蛋白G水平明显更高(P<0.001)。饲喂超过500g/tRE的鸭血清中的免疫球蛋白A水平明显高于CON中的水平(P=0.001)。最后,饲喂500至750g/tRE的鸭子的血清谷胱甘肽过氧化物酶水平明显较高,超氧化物歧化酶,过氧化氢酶,和总抗氧化能力(P<0.05)与CON相比。与CON相比,饲喂超过250g/tRE的鸭子的血清丙二醛水平显着降低(P=0.020)。总的来说,饲粮中添加RE提高了肉鸭22~42d的生长性能和肉品质,这可能与RE的抗氧化和抗炎作用有关。根据血清抗氧化和免疫学参数,
This study aimed to investigate the effects of diets supplemented with different levels of rosemary extract (RE) on the growth performance, meat quality, serum biochemistry, antioxidative capacity, and immunological capacity of Cherry Valley meat ducks. A total of 525 healthy Cherry Valley female meat ducks at 1 d of age were selected for this study. Ducks were randomly divided into 5 treatments with 7 replicates per treatment, and each replicate had 15 ducks. All replicates were randomly assigned to treatments. The study was designed as a dose response experiment. Treatment 1 (CON) was fed with the basal diet, and Treatment 2 to 5 (RE250, RE500, RE750, RE1000) were fed with the basal diet supplemented with 250, 500, 750, and 1,000 g/t RE, respectively. The whole experiment lasted 42 days with early stage (1-21 d) and late stage (22-42 d). Results showed that during 22 to 42 d, ducks that were fed over 500 g/t RE had significantly lower feed gain ratio than the ones in CON (P = 0.006). In addition, ducks in RE750 had significantly lower L* and a* in leg muscle compared with the ones in CON (P < 0.05). Besides, ducks that were fed between 250 and 750 g/t RE had significantly lower total protein level in serum compared with the ones in CON (P = 0.005). Ducks in RE250 and RE750 had significantly lower albumin, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels in serum compared with the ones in CON and RE1000 (P < 0.05), and significant quadratic relationships were noticed between albumin, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol and dietary RE level (P < 0.05). Moreover, ducks that were fed between 500 and 750 g/t RE had significantly higher levels of interleukin-2 in serum compared to the ones in CON and RE1000 (P = 0.003). Ducks in RE250 and RE750 had significantly higher levels of immunoglobulin G in serum compared to the ones in CON and RE1000 (P < 0.001). Ducks that were fed over 500 g/t RE had significantly higher levels of immunoglobulin A in serum compared to the ones in CON (P = 0.001). Finally, ducks that were fed between 500 and 750 g/t RE had significantly higher serum levels of glutathione peroxidase, superoxide dismutase, catalase, and total antioxidant capacity (P < 0.05) compared to the ones in CON. Ducks that were fed over 250 g/t RE had significantly lower serum level of malondialdehyde compared to the ones in CON (P = 0.020). Collectively, dietary supplementation of RE improved the growth performance and meat qualities of meat ducks during 22 to 42 d, which were possibly associated with the antioxidative and anti-inflammatory effects of RE. Based on the serum antioxidative and immunological parameters, we suggested that 500 to 750 g/t was the optimal supplementation rate for RE in diets for meat ducks aged 22 to 42 d.