Burrin D G, Stock R A, Britton R A
Dept. of Anim. Sci., University of Nebraska, Lincoln 68583-0908.
J Anim Sci. 1988 Feb;66(2):513-21. doi: 10.2527/jas1988.662513x.
Two finishing trials were conducted to measure the response of cattle adjusting to high-concentrate diets to dietary monensin level. In trial 1, 54 individually fed Hereford-Angus steers (312 kg), previously fed a two-thirds corn silage: one-third corncob-based diet, were allotted in a 2 X 3 factorial arrangement of treatment with tylosin (0, 11 mg/kg) and monesin (0, 11, 33 mg/kg) fed during a 28-d, grain-adaptation period (fed 75% concentrate for 6 d and then fed 95% concentrate). After 28 d, all steers were continued on their respective levels of tylosin and 33 mg/kg monensin for the remaining 119 d. Daily intake patterns indicated digestive upset in all treatments during adjustment to the 95%-concentrate diet. Blood samples taken during the first 28 d revealed no differences in acid-base status in response to monensin level; however, all steers exhibited reduced (P less than .01) pH and HCO3 and increased (P less than .01) lactate after 4 d on a 75%-concentrate diet. In the initial 28 d, intake decreased (linear P less than .05) as the level of monensin increased. In the total finishing period, however, increasing the level of monensin fed during grain adaptation decreased (linear P less than .05) intake and tended to decrease (linear P = .20) gain with no effect on feed efficiency.(ABSTRACT TRUNCATED AT 250 WORDS)
进行了两项育肥试验，以测定适应高浓度日粮的牛对日粮莫能菌素水平的反应。在试验1中，54头单独饲养的赫里福德-安格斯阉牛（体重312千克），此前饲喂三分之二玉米青贮饲料和三分之一玉米芯为基础的日粮，按照泰乐菌素（0、11毫克/千克）和莫能菌素（0、11、33毫克/千克）的2×3析因处理安排，在28天的谷物适应期（先6天饲喂75%的精饲料，然后95%的精饲料）进行饲喂。28天后，所有阉牛继续按照各自的泰乐菌素水平和33毫克/千克莫能菌素水平，再饲养119天。每日采食模式表明，在适应95%精饲料日粮的调整期，所有处理组的牛都出现了消化紊乱。在最初的28天内采集的血样显示，莫能菌素水平对酸碱状态没有影响；然而，在饲喂75%精饲料日粮4天后，所有阉牛的pH值和碳酸氢根降低（P<0.01），乳酸升高（P<0.01）。在最初的28天内，随着莫能菌素水平的增加，采食量下降（线性，P<0.05）。然而，在整个育肥期，增加谷物适应期饲喂的莫能菌素水平会降低采食量（线性，P<0.05），并使增重有下降趋势（线性，P=0.20），对饲料效率没有影响。（摘要截短至250字）
