Hill G M, Mahan D C, Carter S D, Cromwell G L, Ewan R C, Harrold R L, Lewis A J, Miller P S, Shurson G C, Veum T L
Dept. of Animal Sci., Michigan State Univ., East Lansing 48824-1225, USA.
J Anim Sci. 2001 Apr;79(4):934-41. doi: 10.2527/2001.794934x.
A study involving nine research stations from the NCR-42 Swine Nutrition Committee used a total of 1,978 crossbred pigs to evaluate the effects of dietary ZnO concentrations with or without an antibacterial agent on postweaning pig performance. In Exp. 1, seven stations (IA, MI, MN, MO, NE, ND, and OH) evaluated the efficacy of ZnO when fed to nursery pigs at 0, 500, 1,000, 2,000, or 3,000 mg Zn/kg for a 28-d postweaning period. A randomized complete block experiment was conducted in 24 replicates using a total of 1,060 pigs. Pigs were bled at the 28-d period and plasma was analyzed for Zn and Cu. Because two stations weaned pigs at < 15 d (six replicates) and five stations at > 20 d (18 replicates) of age, the two sets of data were analyzed separately. The early-weaned pig group had greater (P < 0.05) gains, feed intakes, and gain:feed ratios for the 28-d postweaning period as dietary ZnO concentration increased. Later-weaned pigs also had increased (P < 0.01) gains and feed intakes as the dietary ZnO concentration increased. Responses for both weanling pig groups seemed to reach a plateau at 2,000 mg Zn/kg. Plasma Zn concentrations quadratically increased (P < 0.01) and plasma Cu concentrations quadratically decreased (P < 0.01) when ZnO concentrations were > 1,000 mg Zn/kg. Experiment 2 was conducted at seven stations (KY, MI, MO, NE, ND, OH, and OK) and evaluated the efficacy of an antibacterial agent (carbadox) in combination with added ZnO. The experiment was a 2 x 3 factorial arrangement in a randomized complete block design conducted in a total of 20 replicates. Carbadox was added at 0 or 55 mg/kg diet, and ZnO was added at 0, 1,500, or 3,000 mg Zn/ kg. A total of 918 pigs were weaned at an average 19.7 d of age. For the 28-d postweaning period, gains (P < 0.01), feed intakes (P < 0.05), and gain:feed ratios (P < 0.05) increased when dietary ZnO concentrations increased and when carbadox was added. These responses occurred in an additive manner. The results of these studies suggest that supplemental ZnO at 1,500 to 2,000 mg Zn/kg Zn improved postweaning pig performance, and its combination with an antibacterial agent resulted in additional performance improvements.
一项由北中部地区-42猪营养委员会的9个研究站参与的研究，共使用了1978头杂交猪，以评估日粮中氧化锌（ZnO）浓度（添加或不添加抗菌剂）对断奶后仔猪生产性能的影响。在实验1中，7个研究站（爱荷华州、密歇根州、明尼苏达州、密苏里州、内布拉斯加州、北达科他州和俄亥俄州）评估了在断奶后28天的时间里，给保育仔猪饲喂锌含量为0、500、1000、2000或3000毫克/千克的氧化锌的效果。采用随机完全区组试验，共设24个重复，使用了1060头猪。在28天期间对猪进行采血，并分析血浆中的锌和铜含量。由于有两个研究站的仔猪在15日龄前断奶（6个重复），五个研究站的仔猪在20日龄后断奶（18个重复），因此对两组数据分别进行分析。随着日粮中氧化锌浓度的增加，早期断奶仔猪组在断奶后28天的增重、采食量和料重比更高（P<0.05）。随着日粮中氧化锌浓度的增加，晚期断奶仔猪的增重和采食量也有所增加（P<0.01）。两个断奶仔猪组的反应在锌含量为2000毫克/千克时似乎达到了平台期。当氧化锌浓度>1000毫克/千克时，血浆锌浓度呈二次增加（P<0.01），血浆铜浓度呈二次下降（P<0.01）。实验2在7个研究站（肯塔基州、密歇根州、密苏里州、内布拉斯加州、北达科他州、俄亥俄州和俄克拉何马州）进行，评估了抗菌剂（卡巴氧）与添加的氧化锌联合使用的效果。该实验采用2×3析因设计，随机完全区组设计，共设20个重复。卡巴氧添加量为0或55毫克/千克日粮，氧化锌添加量为0、1500或3000毫克/千克锌。共有918头仔猪平均在19.7日龄断奶。在断奶后28天期间，随着日粮中氧化锌浓度的增加以及添加卡巴氧，增重（P<0.01）、采食量（P<0.05）和料重比（P<0.05）均增加。这些反应以相加的方式出现。这些研究结果表明，添加1500至2000毫克/千克锌的氧化锌可改善断奶后仔猪的生产性能，其与抗菌剂联合使用可进一步提高生产性能。
