Department of Anatomy and Histology, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh.
Department of Anatomy and Histology, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh.
Poult Sci. 2022 Jul;101(7):101904. doi: 10.1016/j.psj.2022.101904. Epub 2022 Apr 6.
Growth promoters are added with broiler feed to boost the overall feed efficiency and growth rate. The current study investigated the effect of dexamethasone (DEX)-a commonly used growth promoter-on the broiler growth rate, meat quality, and muscle biology. Four homogenous groups (20 chicks/group) of broiler one-day-old chicks were fed commercial broiler feed where the treatment groups received 3, 5, and 7 mg/kg of DEX with their diet for 28 d. Feed consumption and body weight were monitored on a daily basis. Muscle samples were collected on 7, 14, 21, and 28 d of the experiment to investigate meat quality and muscular biology. The residue of DEX in meat was detected using thin-layer chromatography. We observed that DEX had substantially decreased (P < 0.05) feed intake, feed efficiency, and overall weight gain in the broiler. While the weight of breast and thigh meat was decreased, the relative meat weight (meat/body weight) was increased significantly in chicks fed DEX. Simultaneously, body fat decreased while the percentage of fat increased significantly (P < 0.05) in the DEX groups. Contrariwise, DEX improved the investigated meat quality parameters with the potential threat of accumulation of DEX residue in the meat at a high dose (7 mg/kg). We also observed that DEX significantly increased the number of myofibers and decreased the cross-sectional area of myofibers. Based on these findings, we conclude that DEX reduces feed intake, feed efficiency, and growth rate, but might improve meat quality with a potential risk of residual DEX accumulation if fed at a high dose.
生长促进剂被添加到肉鸡饲料中以提高整体饲料效率和生长速度。本研究调查了地塞米松（DEX）-一种常用的生长促进剂-对肉鸡生长速度、肉质和肌肉生物学的影响。将 4 组同质的肉鸡 1 日龄小鸡（每组 20 只）喂食商业肉鸡饲料，其中处理组在饮食中添加 3、5 和 7mg/kg 的 DEX 28 天。每天监测饲料消耗和体重。在实验的第 7、14、21 和 28 天收集肌肉样本，以研究肉质和肌肉生物学。使用薄层层析法检测肉中的 DEX 残留量。我们观察到 DEX 显著降低（P<0.05）了肉鸡的饲料摄入量、饲料效率和总增重。虽然胸部和大腿肉的重量下降，但喂食 DEX 的小鸡的相对肉重（肉/体重）显著增加。同时，体脂减少，而脂肪百分比显著增加（P<0.05）在 DEX 组中。相反，DEX 改善了研究中的肉质参数，但高剂量（7mg/kg）可能会导致 DEX 残留的积累。我们还观察到 DEX 显著增加了肌纤维数量，减少了肌纤维的横截面积。基于这些发现，我们得出结论，DEX 降低了饲料摄入量、饲料效率和生长速度，但如果高剂量喂食，可能会改善肉质，但存在 DEX 残留积累的潜在风险。
