Wilson D J, Das H H, Gonzalez R N, Sears P M
Quality Milk Promotion Services, College of Veterinary Medicine, Cornell University, Ithaca, NY 14850, USA.
J Am Vet Med Assoc. 1997 May 15;210(10):1499-502.
To determine whether particular dairy management practices and herd characteristics were associated with somatic cell count (SCC) of bulk tank milk.
Analysis of records.
Milk samples collected from 59,435 cows housed in 843 dairy herds between March 1992 and June 1994.
Results of bacterial culture of milk samples and data on farm housing, sanitation, milking system, and management were collected. Multiple regression analysis was used to determine sources of variation in bulk tank milk SCC among herds.
Prevalence of Streptococcus agalactiae and Staphylococcus aureus mastitis was associated with bulk tank milk SCC. In herds free of S agalactiae mastitis, prevalence of S aureus and Corynebacterium bovis mastitis were important. For herds without S agalactiae mastitis, use of sawdust bedding was associated with a decrease in SCC and a dirty loose housing area was associated with an increase. Increased milk production, repeated mastitis control visits, and use of particular predip compounds were significantly associated with reduced SCC in all herds, regardless of whether any cows in the herd had S agalactiae mastitis. In herds with S agalactiae mastitis, use of iodine (certain concentrations), chlorhexidine, peroxide, or sodium chlorite-lactic acid as a predip was associated with a decrease in SCC. Only use of sodium chlorite-lactic acid predip was significantly associated with a decrease in SCC in herds without S agalactiae mastitis.
Important factors associated with bulk tank milk SCC were prevalence of S agalactiae and S aureus mastitis, careful application of particular predip compounds, avoiding a dirty loose housing area, and use of a service to regularly monitor prevalence of mastitis in the herd.
确定特定的奶牛场管理措施和畜群特征是否与奶罐奶的体细胞计数（SCC）相关。
记录分析。
1992年3月至1994年6月期间，从843个奶牛场的59435头奶牛采集的牛奶样本。
收集牛奶样本的细菌培养结果以及关于农场住房、卫生、挤奶系统和管理的数据。采用多元回归分析来确定各畜群奶罐奶SCC的变异来源。
无乳链球菌和金黄色葡萄球菌乳腺炎的患病率与奶罐奶SCC相关。在无无乳链球菌乳腺炎的畜群中，金黄色葡萄球菌和牛棒状杆菌乳腺炎的患病率很重要。对于无无乳链球菌乳腺炎的畜群，使用锯末垫料与SCC降低相关，而肮脏的散养区与SCC升高相关。在所有畜群中，无论畜群中是否有奶牛患无乳链球菌乳腺炎，产奶量增加、反复进行乳腺炎控制访视以及使用特定的预浸剂都与SCC降低显著相关。在有无乳链球菌乳腺炎的畜群中，使用碘（特定浓度）、洗必泰、过氧化物或亚氯酸钠 - 乳酸作为预浸剂与SCC降低相关。仅在无无乳链球菌乳腺炎的畜群中，使用亚氯酸钠 - 乳酸预浸剂与SCC降低显著相关。
与奶罐奶SCC相关的重要因素有无乳链球菌和金黄色葡萄球菌乳腺炎的患病率、谨慎使用特定的预浸剂、避免肮脏的散养区以及使用服务定期监测畜群中乳腺炎的患病率。
