[奶牛场的乳房健康。1. 对300个荷兰农场的纵向研究结果]

Tijdschr Diergeneeskd. 1999 Jun 1;124(11):338-44.

Udder health was studied in 300 dairy herds grouped in three categories according to the bulk milk somatic cell count. In all herds, lactating cows were housed in a free-stall barn during the winter. All herds participated in a three or four-weekly milk recording system, had annual production quota between 300,000 and 900,000 kg, and were stocked with cows of the Holstein-Friesian or Dutch Friesian breeds. The incidence of clinical mastitis was not different among herds with a low (< or = 150,000), middle (151,000 to 250,000), or high (251,000 to 400,000 cells/ml) bulk milk somatic cell count. Clinical mastitis caused by Gram-negative pathogens occurred more often in herds with a low bulk milk somatic cell count. Clinical mastitis caused by Staphylococcus aureus, Streptococcus dysgalactiae, or Streptococcus agalactiae occurred more often in herds with a high bulk milk somatic cell count; however, the incidence of clinical Streptococcus uberis mastitis was not different among the three herd categories. The differences in bulk milk somatic cell count between the categories could be explained by the management practices studied. The incidence of clinical E. coli mastitis was mostly related to housing, hygiene, and milking machine. The incidence of clinical Staphylococcus aureus mastitis was associated with factors that were related to the bulk milk somatic cell count and to factors of which it was not clear whether they were a cause or effect of the high incidence of Staphylococcus aureus mastitis. The incidence of clinical Streptococcus dysgalactiae mastitis was related to nutrition, milking technique, and milking machine. The incidence of clinical Streptococcus uberis mastitis was associated with housing, nutrition, and milking machine. Two groups of farmers and herds could be differentiated. The first group was identified as 'Clean and Accurate', and the second group as 'Quick and Dirty'. The relationship between these two groups and bulk milk somatic cell count category was high. However, the relationship between the two groups and the incidence of clinical mastitis was weak.

根据原奶体细胞计数，将300个奶牛群分为三类，对其乳房健康状况进行了研究。在所有牛群中，泌乳奶牛在冬季被安置在自由栏舍中。所有牛群都参与了每三到四周一次的牛奶检测系统，年生产配额在30万至90万千克之间，并且饲养的是荷斯坦 - 弗里生或荷兰弗里生品种的奶牛。原奶体细胞计数低（≤150,000）、中（151,000至250,000）或高（251,000至400,000个细胞/毫升）的牛群中，临床乳腺炎的发病率没有差异。由革兰氏阴性病原体引起的临床乳腺炎在原奶体细胞计数低的牛群中更常见。由金黄色葡萄球菌、无乳链球菌或停乳链球菌引起的临床乳腺炎在原奶体细胞计数高的牛群中更常见；然而，临床乳房链球菌性乳腺炎的发病率在这三类牛群中没有差异。各类牛群之间原奶体细胞计数的差异可以通过所研究的管理措施来解释。临床大肠杆菌性乳腺炎的发病率主要与牛舍、卫生和挤奶机有关。临床金黄色葡萄球菌性乳腺炎的发病率与原奶体细胞计数相关的因素以及尚不清楚是金黄色葡萄球菌性乳腺炎高发病率的原因还是结果的因素有关。临床无乳链球菌性乳腺炎的发病率与营养、挤奶技术和挤奶机有关。临床乳房链球菌性乳腺炎的发病率与牛舍、营养和挤奶机有关。可以区分出两组农民和牛群。第一组被认定为“清洁且准确”，第二组为“快速且脏乱”。这两组与原奶体细胞计数类别之间的关系密切。然而，这两组与临床乳腺炎发病率之间的关系较弱。