Department of Animal Sciences, University of Illinois, Urbana, IL 61801, USA.
J Dairy Sci. 2012 Oct;95(10):5831-44. doi: 10.3168/jds.2011-5042. Epub 2012 Aug 9.
The aims of the experiment were to evaluate the effects of source of trace minerals (TM) and plane of nutrition (PN) early in life on growth and health of transported calves. Ninety male Holstein calves <1 wk old were assigned to treatments in a 2×2 factorial arrangement of PN and TM source in a randomized complete block design. Calves assigned to low PN (LPN) received milk replacer [22% crude protein (CP), 20% fat, 568 g of powder/d for wk 1 to 4, and 284 g of powder/d for wk 5] plus ad libitum access to starter [18% CP, dry matter (DM) basis, for wk 1 to 12] and a limited amount of hay (0.5 kg/d as fed, for wk 10 to 12); LPN calves were weaned at 6 wk. During wk 13 to 20, LPN calves were fed 3.2 kg/d of grower mix (16% CP, DM basis) plus chopped hay for ad libitum intake. Calves assigned to high PN (HPN) received variable amounts of milk replacer (28% CP; 20% fat; and 810, 1,136, and 568 g of powder/d for wk 1, 2 to 6, and 7, respectively) plus ad libitum access to starter (22% CP, DM basis, wk 1 to 12) and limited hay (0.5 kg/d as fed, for wk 10 to 12); HPN calves were weaned at wk 7. Calves assigned to HPN were offered grower mix for ad libitum intake plus a limited amount of chopped hay (0.5 kg/d, as-fed basis) from wk 13 to 20. Milk replacers were formulated to contain balanced amounts of either inorganic (I) or organic (O) TM (50, 50, 10, and 100mg/kg of Zn, Mn, Cu, and Fe, respectively), whereas respective ITM or OTM starters and growers contained Zn, Mn, Cu, and Co at 70, 55, 12, and 1mg/kg. The HPN treatments increased final body weight and stature measurements, average daily gain, and gain-to-feed ratio through wk 20. Starter intake was lower for calves fed HPN. The OTM increased growth when supplemented to HPN but not when supplemented to LPN. During the liquid-feeding period, fecal scores were more fluid for calves fed HPN but measures of health status did not differ among diets. Results indicated that an enhanced nutritional program during early life allowed calves to have greater overall growth and maintain a normal health status throughout the preweaning period. High PN and OTM were synergistic in increasing early growth of calves.
实验目的是评估生命早期微量矿物质（TM）和营养水平（PN）来源对运输牛犊生长和健康的影响。90 头 1 周龄以下的雄性荷斯坦牛犊按 PN 和 TM 来源的 2×2 析因设计在随机完全区组设计中进行处理分配。低 PN（LPN）组牛犊接受代乳粉[22%粗蛋白（CP），20%脂肪，第 1 至 4 周 568 克/粉，第 5 周 284 克/粉]，并自由采食起始料[18%CP，干物质（DM）基础，第 1 至 12 周]和有限量的干草（第 10 至 12 周为 0.5 公斤/天）；LPN 牛犊在 6 周龄断奶。在第 13 至 20 周期间，LPN 牛犊每天喂食 3.2 公斤生长料（16%CP，DM 基础）和切碎的干草，自由采食。高 PN（HPN）组牛犊接受不同量的代乳粉（28%CP；20%脂肪；第 1、2 至 6 周和第 7 周分别为 810、1136 和 568 克/粉），并自由采食起始料（22%CP，DM 基础，第 1 至 12 周）和有限量的干草（第 10 至 12 周为 0.5 公斤/天）；HPN 牛犊在第 7 周断奶。HPN 组牛犊在第 13 至 20 周期间自由采食生长料，同时还提供有限量的切碎干草（0.5 公斤/天，干物质基础）。代乳粉的 TM（锌、锰、铜和铁分别为 50、50、10 和 100mg/kg）被配方为含有平衡的无机（I）或有机（O）TM；相应的 ITM 或 OTM 起始料和生长料中含有 70、55、12 和 1mg/kg 的锌、锰、铜和钴。HPN 处理增加了 20 周龄时的最终体重和体尺测量、平均日增重和增重/饲料比。HPN 组牛犊的起始料采食量较低。O 型 TM 补充 HPN 时会增加生长，但补充 LPN 时则不会。在液体喂养期间，HPN 组牛犊的粪便评分更稀，但不同日粮之间的健康状况测量没有差异。结果表明，生命早期强化营养方案使牛犊具有更好的整体生长速度，并在整个断奶前阶段保持正常的健康状态。高 PN 和 OTM 协同作用可增加牛犊早期生长。
