Sahin Kazim, Kucuk Omer
Department of Animal Nutrition, Faculty of Veterinary Science, Firat University, Elazig Turkey.
J Nutr. 2003 Sep;133(9):2808-11. doi: 10.1093/jn/133.9.2808.
The study was conducted to determine whether zinc supplementation could alleviate the detrimental effects of high ambient temperature (34 degrees C) on egg production, digestibility of nutrients and antioxidant status in laying Japanese quail. Quail (n = 180; 52 d old) were divided into six groups (n = 30/group) and were fed a basal diet or the basal diet supplemented with 30 or 60 mg of zinc (ZnSO(4). H(2)O)/kg diet. Birds were kept at 22 degrees C and 58% relative humidity (RH). At 13 wk of age, the thermoneutral (TN) groups remained at the same temperature, whereas the heat-stress (HS) groups were kept in an environmentally controlled room at 34 degrees C and 42% RH for 3 wk. Heat exposure decreased egg production in birds fed the basal diet (P = 0.001). Linear increases in feed intake (P = 0.01) and egg production (P = 0.004) and improved feed efficiency (P = 0.01) and egg quality variables (P <or= 0.05) occurred in zinc-supplemented groups reared under HS conditions. Heat exposure decreased digestibility of nutrients (P = 0.001), and these decreases were ameliorated by zinc supplementation (P <or= 0.05). Serum vitamin C (P = 0.05), vitamin E (P = 0.01) and zinc (P = 0.001) concentrations increased linearly, whereas malondialdehyde concentrations decreased (P = 0.002) as dietary zinc supplementation increased. No significant differences in any values were observed in the TN groups (P > 0.05). Results of the present study suggest that supplementation with 60 mg zinc/kg diet protects quail by reducing the negative effects of heat stress.
本研究旨在确定补充锌是否可以减轻环境高温（34摄氏度）对产蛋日本鹌鹑产蛋性能、养分消化率和抗氧化状态的不利影响。鹌鹑（n = 180；52日龄）被分为六组（每组n = 30），分别饲喂基础日粮或添加了30或60毫克锌（硫酸锌·水合物）/千克日粮的基础日粮。鹌鹑饲养在22摄氏度、相对湿度58%的环境中。13周龄时，热中性（TN）组保持在相同温度，而热应激（HS）组在环境控制的房间中饲养在34摄氏度、相对湿度42%的条件下3周。热暴露降低了饲喂基础日粮鹌鹑的产蛋性能（P = 0.001）。在热应激条件下饲养的补充锌组中，采食量（P = 0.01）和产蛋性能呈线性增加（P = 0.004），饲料效率提高（P = 0.01），蛋品质变量改善（P≤0.05）。热暴露降低了养分消化率（P = 0.001），而补充锌改善了这些降低情况（P≤0.05）。随着日粮锌添加量的增加，血清维生素C（P = 0.05）、维生素E（P = 0.01）和锌（P = 0.001）浓度呈线性增加，而丙二醛浓度降低（P = 0.002）。在热中性组中，各项值均未观察到显著差异（P>0.05）。本研究结果表明，日粮中添加60毫克锌/千克可通过减轻热应激的负面影响来保护鹌鹑。
