Efficacy of intrammary tilmicosin and risk factors for cure of Staphylococcus aureus infection in the dry period
Efficacy of intrammary tilmicosin and risk factors for cure of Staphylococcus aureus infection in the dry period
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DOI：
10.3168/jds.s0022-0302(03)73596-6
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发表时间：
2003-01-01
影响因子：
3.5
通讯作者：
Bagg, R
中科院分区：
文献类型：
--
作者：
Dingwell, RT;Leslie, KE;Bagg, R
本研究的目的是评估干奶时乳房内注射替米考星消除金黄色葡萄球菌感染的功效，并确定干奶期间金黄色葡萄球菌治愈的危险因素。总共 219 头自然感染的奶牛（代表 308 个小区）被随机分配在干燥时接受两种治疗中的一种。奶牛接受 500 mg 苄星氯唑西林的乳房内输注，或含有 1500 mg 替米考星的无菌溶液。所有奶牛在干奶前以及随后泌乳期的第 1、2 和 4 周均以无菌方式采集了 1/4 牛奶样品 3 次。总体而言，62% 的奶牛和 67.5% 感染金黄色葡萄球菌的牛群在干奶期治愈。奶牛和牛服用替米考星后的治愈率分别为 67.3% 和 72.5%。相比之下，使用氯唑西林治疗的奶牛和牛群的治愈率分别为 56.9% 和 62.9%。接受替米考星治疗的奶牛治愈的可能性提高了 2.1 倍。随着最后一次 DHI 测试的线性分数的增加以及金黄色葡萄球菌排出量的增加，奶牛的治愈率下降。在干燥前多次培养呈阳性的季度治愈的可能性较小。位于乳房前部的金黄色葡萄球菌感染的治愈率是后部的金黄色葡萄球菌感染的两倍。这项研究的结果表明，干燥时乳房内注射替米考星对于治疗干燥期现有的金黄色葡萄球菌是有效的。确定了与金黄色葡萄球菌治愈相关的危险因素。
The objective of this study was to evaluate the efficacy of intramammary tilmicosin, administered at drying-off, for eliminating Staphylococcus aureus infection, and to identify risk factors for S. aureus cure during the dry period. A total of 219 naturally infected cows, representing 308 quarters, were randomized to receive either one of two treatments at drying-off. Cows received either an intramammary infusion of 500 mg of benzathine cloxacillin, or a sterile solution containing 1500 mg of tilmicosin. All cows had quarter milk samples taken aseptically three times before dry-off, and at wk 1, 2, and 4 of the subsequent lactation. Overall, 62% of cows and 67.5% of quarters infected with, S. aureus cured during the dry period. The cure following administraton of tilmicosin was 67.3 and 72.5% for cows and quarters, respectively. By comparison, the cure achieved with cloxacillin was 56.9 and 62.9% of cows and quarters. Cows receiving tilmicosin were 2.1 times more likely to cure. The cure rate for cows decreased as the linear score on the last DHI test increased, and as the amount of S. aureus being shed increased. Quarters that cultured positive multiple times before drying-off were less likely to cure. Staphylococcus aureus infections located in front quarters of the udder were 2 times more likely to cure than those in hind quarters. Results of this study demonstrate that intramammary tilmicosin at drying-off is efficacious in curing existing S. aureus during the dry period. Risk factors associated with the cur e of S. aureus were identified.