PDF(Pubmed)
Abstract：
Prevention of new intramammary infection (NIMI) during the dry period (DP) is essential to prevent the development of mastitis in dairy cows. To investigate risk factors for NIMI, 212 cows, comprising a total of 848 udder quarters, were examined in this study. Quarter milk samples were taken on the day of drying off and 7 ± 3 days after calving. Cow- and quarter-level associated risk factors were assessed at the beginning of the DP and after calving. In total, 7.1% of the udder quarters developed an NIMI between the samplings. Non-aureus staphylococci (40.4%) and Gram-negative pathogens (22.8%) were most frequently the cause of NIMI. The observed milk leakage prevalence was 16.7%, with a peak 24 h after drying off. Simultaneously, the udder pressure peaked 24 h after drying off. A significant correlation between milk yield on the day before drying off and milk leakage could be proven. Cows with quarters leaking milk produced an average milk yield of 28.32 kg on the day before drying off. Generalised linear mixed models and odds ratios were calculated to determine the significant risk factors for NIMI during the DP and early lactation. Quarters leaking milk had 3.4 higher odds for NIMI between the samplings compared to quarters without milk leakage. Quarters from cows with dirty udders had 3.1 higher odds of developing an NIMI between the samplings compared to quarters from cows with clean udders. The results of this study demonstrate the importance of dry cow management before drying off and during the critical period of active involution of the udder tissue.
摘要：
在干旱期（DP）预防新的乳房内感染（NIMI）对于预防奶牛乳腺炎的发展至关重要。为了调查NIMI的危险因素，212头牛,总共848个乳房宿舍，在这项研究中进行了检查。在干燥当天和产卵后7±3天取四分之一牛奶样品。在DP开始和产卵后评估了Cow和季度水平相关的风险因素。总的来说,7.1%的乳房宿舍在采样之间产生了NIMI。非金黄色葡萄球菌（40.4％）和革兰氏阴性病原体（22.8％）是NIMI的最常见原因。观察到的牛奶泄漏发生率为16.7％，干燥后24小时出现峰值。同时,乳房压力在干燥后24小时达到峰值。可以证明干燥前一天的牛奶产量与牛奶泄漏之间存在显着相关性。四分之一牛奶泄漏的奶牛在干燥前一天的平均产奶量为28.32千克。计算了广义线性混合模型和比值比，以确定DP和泌乳早期NIMI的重要危险因素。与没有牛奶泄漏的宿舍相比，在采样之间，泄漏牛奶的宿舍的NIMI几率要高3.4。与乳房干净的母牛的四分之一相比，乳房脏的母牛的四分之一在采样之间发生NIMI的几率要高3.1。这项研究的结果表明，在干燥之前和乳房组织主动退化的关键时期，对干牛进行管理的重要性。
