Department of Animal and Population Health, University of Liverpool, Neston, Wirral CH64 7TE, UK.
Res Vet Sci. 2012 Feb;92(1):13-7. doi: 10.1016/j.rvsc.2010.10.006. Epub 2010 Nov 11.
Intramammary infections (IMI) during the dry period can be reduced through the use of dry cow therapy (DCT); in the future, its blanket use is likely to be questioned in the light of public concern regarding the routine use of antibiotics in food producing animals. One possible alternative is to limit DCT to cows with IMI just before drying off, which would require a quick, simple identification of sub-clinical IMI. In the present study we examined quarter milk samples obtained from 240 cows one week before and on the day of drying off, using the California mastitis test (CMT) and for IMI by bacteriological culture. The results indicated that high CMT scores at drying off may be good indicators of IMI: there was a significant association between the frequency of isolation of major pathogens and the CMT score in milk samples obtained one week before (Pearson's χ(2)=27.04, df=4, p<0.001) and those at drying off (Pearson's χ(2)=25.87, df=4, p<0.001).
干奶期的乳腺炎（IMI）可以通过干奶期疗法（DCT）来减少；鉴于公众对在食用动物中常规使用抗生素的担忧，未来其广泛应用可能会受到质疑。一种可能的替代方法是将 DCT 仅限于即将停奶的患有 IMI 的奶牛，这需要快速、简单地识别亚临床 IMI。在本研究中，我们使用加利福尼亚乳房炎测试（CMT）检查了 240 头奶牛在停奶前一周和停奶当天的四个乳区奶样，并通过细菌培养检查 IMI。结果表明，停奶时 CMT 评分高可能是 IMI 的良好指标：在停奶前一周（皮尔逊 χ(2)=27.04，df=4，p<0.001）和停奶时（皮尔逊 χ(2)=25.87，df=4，p<0.001）获得的乳样中，主要病原体的分离频率与 CMT 评分之间存在显著相关性。
