Kerr B J, Trabue S L, Andersen D S
J Anim Sci. 2017 Sep;95(9):4030-4036. doi: 10.2527/jas2017.1732.
Three experiments were conducted to determine the effect of narasin on growth performance and on GE and nutrient digestibility in nursery, grower, and finishing pigs fed either a corn-soybean meal (CSBM) diet or a CSBM diet supplemented with distillers dried grains with solubles (DDGS), in combination with either 0 or 30 mg narasin/kg of diet. In Exp. 1 (64 gilts, initial BW = 9.0 kg, SD = 1.0 kg) and Exp. 2 (60 gilts. initial BW = 81.1 kg, SD = 6.1 kg), gilts were allotted into individual pens and fed their experimental diets for 24 and 21 d, respectively. On the last 2 d of each experiment, fecal samples were collected to assess apparent total tract digestibility (ATTD) of GE and various nutrients. In Exp. 3, 2 separate groups of 24 gilts (initial BW = 145.1 kg, SD = 7.8 kg) were allotted to individual metabolism crates and fed their experimental diets for 30 d prior to a time-based 6-d total fecal collection period to assess GE and nutrient digestibility. In Exp. 1, there was an interaction between diet type and narasin addition for G:F and for many of the ATTD coefficients measured. When narasin was supplemented to the CSBM diet, ATTD of GE, DM, C, S, phosphorus, NDF, and ADF was either not changed or reduced, while when narasin was supplemented to DDGS diets, these same ATTD parameters were increased (interaction, ≤ 0.05). Even though ADG and ADFI were not affected, G:F was improved in pigs fed the CSBM diet with supplemental narasin, but was reduced in pigs fed the DDGS diet with supplemental narasin (interaction, < 0.05). In Exp. 2, there was an interaction between diet type and narasin supplementation only for ATTD of Ca (interaction, < 0.01), in that narasin supplementation did not change the ATTD of Ca in pigs fed the CSBM diet, while narasin supplementation reduced the ATTD of Ca in pigs fed the DDGS containing diet. In Exp. 3, there was an interaction between diet and narasin only for ATTD of C (interaction, < 0.01) in that narasin supplementation resulted in an increased ATTD of C in pigs fed the CSBM diet, while narasin supplementation to the DDGS containing diet resulted in a reduced ATTD of Ca. In general, the data indicate that narasin interacted with and had its largest effect on pig performance and GE or nutrient digestibility in 9 to 23 kg pigs compared to pigs weighing greater than 80 kg. The data also indicate that the addition of DDGS reduced GE, DM, Ca, and N digestibility, regardless of BW.
进行了三项试验，以确定那拉菌素对保育猪、生长猪和育肥猪生长性能、总能（GE）和养分消化率的影响。这些猪分别饲喂玉米 - 豆粕（CSBM）日粮或添加了玉米干酒糟及其可溶物（DDGS）的CSBM日粮，并在日粮中分别添加0或30 mg/kg的那拉菌素。在试验1（64头后备母猪，初始体重 = 9.0 kg，标准差 = 1.0 kg）和试验2（60头后备母猪，初始体重 = 81.1 kg，标准差 = 6.1 kg）中，将后备母猪分配到个体栏中，分别饲喂试验日粮24天和21天。在每个试验的最后2天，采集粪便样本以评估GE和各种养分的表观全肠道消化率（ATTD）。在试验3中，将2组各24头后备母猪（初始体重 = 145.1 kg，标准差 = 7.8 kg）分配到个体代谢笼中，在基于时间的6天总粪便收集期之前，饲喂试验日粮30天，以评估GE和养分消化率。在试验1中，日粮类型和那拉菌素添加之间存在交互作用，影响了料重比（G:F）以及所测定的许多ATTD系数。当那拉菌素添加到CSBM日粮中时，GE、干物质（DM）、粗蛋白（C）、粗灰分（S）、磷、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）的ATTD要么没有变化，要么降低；而当那拉菌素添加到DDGS日粮中时，这些相同的ATTD参数增加（交互作用，≤0.05）。尽管平均日增重（ADG）和平均日采食量（ADFI）不受影响，但在饲喂添加那拉菌素的CSBM日粮的猪中，G:F得到改善，而在饲喂添加那拉菌素的DDGS日粮的猪中，G:F降低（交互作用，<0.05）。在试验2中，日粮类型和那拉菌素添加之间仅对钙的ATTD存在交互作用（交互作用，<0.01），即那拉菌素添加对饲喂CSBM日粮的猪的钙ATTD没有影响，而那拉菌素添加降低了饲喂含DDGS日粮的猪的钙ATTD。在试验3中，日粮和那拉菌素之间仅对粗蛋白的ATTD存在交互作用（交互作用，<0.01），即那拉菌素添加使饲喂CSBM日粮的猪的粗蛋白ATTD增加，而那拉菌素添加到含DDGS日粮中则导致钙的ATTD降低。总体而言，数据表明，与体重超过80 kg的猪相比，那拉菌素与9至23 kg猪的生长性能以及GE或养分消化率相互作用且影响最大。数据还表明，无论体重如何，添加DDGS都会降低GE、DM、钙和氮的消化率。
