Tang Z G, Chen G Y, Li L F, Wen C, Wang T, Zhou Y M
J Anim Sci. 2015 Feb;93(2):620-6. doi: 10.2527/jas.2014-8165.
This study investigated Zn-bearing zeolite clinoptilolite (Zn-ZCP) as a Zn supplement on performance, organ or tissue development, Zn accumulation in tissues, and gene expression of Zn transporters in the duodenum of broilers. A total of 300 1-d-old Arbor Acres chickens were randomly allocated to 5 dietary treatments with 6 replicate cages of 10 birds per treatment for a 21-d feeding period. The treatments comprised a basal corn–soybean meal diet without supplemental Zn (the control) or similar diets supplemented with 80 mg/kg Zn from ZnSO4 or 20, 40, or 80 mg/kg Zn from Zn- ZCP, respectively. Supplementation of Zn-ZCP had a positive effect on G:F (linear, P < 0.05) and had tendency difference on ADG (linear, P < 0.1) of broilers during 1 to 21 d. Incremental Zn-ZCP inclusion in the diet increased the fresh weight of the pancreas (linear, P < 0.05) and tibia (linear, P < 0.05) in broilers on d 14. The same trend to the fresh weight of the tibia (linear, P < 0.05) and pancreas (linear, P < 0.05) was observed on d 21. Increasing Zn-ZCP level showed a linear response on Zn concentration in the liver (linear, P < 0.001), pancreas (linear, P < 0.05), and tibia (linear, P < 0.05) on d 14. The same trend of Zn concentrations in pancreas (linear, P < 0.05) and tibia (linear, P < 0.001) was observed on d 21. The mRNA levels of Zn transporter 2 (ZnT-2) and Zn transporter 5 (ZnT-5) in the duodenum of chicks fed the diet with 80 mg/kg Zn from Zn-ZCP did not differ from those of chicks fed the control diet, but both were lower (P < 0.05) than those of chicks fed ZnSO4 diet. Metallothionein (MT) mRNA levels of broilers fed the diet supplemented with 80 mg/kg Zn from Zn-ZCP or ZnSO4 was higher (P < 0.05) than that in the control group. Dietary treatments did not affect the mRNA expression of Zn transporter 1 (ZnT-1) or metal response element-binding transcription factor-1 (MTF-1). In conclusion, as a Zn supplement, Zn-ZCP was comparable to ZnSO4 for enhancing Zn accumulation and growth performance of broilers during 1 to 21 d. Broilers fed the diet with 80 mg/kg Zn from Zn-ZCP had different expressions of ZnT-2 and ZnT-5 in the duodenum compared with those fed the ZnSO4 diet.
本研究探讨了含锌沸石斜发沸石（Zn-ZCP）作为锌补充剂对肉鸡生长性能、器官或组织发育、组织中锌积累以及十二指肠中锌转运蛋白基因表达的影响。总共300只1日龄的艾维茵肉鸡被随机分配到5种日粮处理组，每组6个重复笼，每个处理10只鸡，进行为期21天的饲养期。处理组包括不添加锌的基础玉米-豆粕日粮（对照组）或分别添加80mg/kg硫酸锌锌或20、40或80mg/kg Zn-ZCP的类似日粮。在1至21天期间，添加Zn-ZCP对肉鸡的料肉比有积极影响（呈线性，P<0.05），对平均日增重有趋势性差异（呈线性，P<0.1）。日粮中Zn-ZCP添加量的增加使14日龄肉鸡的胰腺鲜重（呈线性，P<0.05）和胫骨鲜重（呈线性，P<0.05）增加。在21日龄时观察到胫骨（呈线性，P<0.05）和胰腺（呈线性，P<0.05）鲜重有相同趋势。在14日龄时，增加Zn-ZCP水平对肝脏（呈线性，P<0.001）、胰腺（呈线性，P<0.05）和胫骨（呈线性，P<0.05）中的锌浓度呈线性反应。在21日龄时观察到胰腺（呈线性，P<0.05）和胫骨（呈线性，P<0.001）中锌浓度的相同趋势。饲喂含80mg/kg Zn-ZCP日粮的雏鸡十二指肠中锌转运蛋白2（ZnT-2）和锌转运蛋白5（ZnT-5）的mRNA水平与饲喂对照日粮的雏鸡没有差异，但均低于（P<0.05）饲喂硫酸锌日粮的雏鸡。饲喂添加80mg/kg Zn-ZCP或硫酸锌日粮的肉鸡金属硫蛋白（MT）mRNA水平高于（P<0.05）对照组。日粮处理对锌转运蛋白1（ZnT-1）或金属反应元件结合转录因子-1（MTF-1）的mRNA表达没有影响。总之，作为锌补充剂，Zn-ZCP在提高1至21日龄肉鸡的锌积累和生长性能方面与硫酸锌相当。与饲喂硫酸锌日粮的肉鸡相比，饲喂含80mg/kg Zn-ZCP日粮的肉鸡十二指肠中ZnT-2和ZnT-5的表达不同。
