Bailey J S, Blankenship L C, Stern N J, Cox N A, McHan F
USDA ARS RRC, Athens, Georgia 30613.
Avian Dis. 1988 Apr-Jun;32(2):324-9.
Chicks were treated orally on the day of hatch with either fresh or frozen competitive exclusion (CE) cultures (native gut microflora). Chicks were fed either unmedicated feed or one of five commercial broiler starter rations or nine experimental feed mixtures containing varying amounts and combinations of anticoccidial and antimicrobial medicaments. After 2 days, they were challenged with approximately 10(6) colony-forming units of a nalidixic-acid-resistant strain of Salmonella typhimurium. Six days later, chicks were sacrificed and ceca were analyzed for S. typhimurium. Colonization of 2-day-old chicks was prevented or at least greatly reduced in most instances by treatment of chicks with a CE culture, but the efficacy of CE broth cultures stored at -70 C diminished over time. Not all CE cultures tested gave equal protection against Salmonella colonization, and CE cultures were more susceptible to some feed additives than others. Of the commercial or experimental feed tested, only the feed containing the combination of nicarbazin and bacitracin interfered with the protective effect of the CE culture.
雏鸡在孵化当天口服新鲜或冷冻的竞争性排斥（CE）培养物（天然肠道微生物群）。雏鸡饲喂未添加药物的饲料，或五种商业肉鸡开食料之一，或九种含有不同数量和组合的抗球虫药和抗菌药物的实验饲料混合物。两天后，用约10(6)个耐萘啶酸的鼠伤寒沙门氏菌菌落形成单位对它们进行攻毒。六天后，处死雏鸡并分析盲肠中的鼠伤寒沙门氏菌。在大多数情况下，用CE培养物处理雏鸡可防止或至少大大减少2日龄雏鸡的定殖，但储存在-70℃的CE肉汤培养物的效力会随着时间的推移而降低。并非所有测试的CE培养物对沙门氏菌定殖都有同等的保护作用，并且CE培养物对某些饲料添加剂比其他添加剂更敏感。在所测试的商业或实验饲料中，只有含有尼卡巴嗪和杆菌肽组合的饲料会干扰CE培养物的保护作用。
