Vandeputte-Van Messom G, Burvenich C, Roets E, Massart-Leën A M, Heyneman R, Kremer W D, Brand A
Department of Veterinary Physiology, University of Ghent, Belgium.
J Dairy Res. 1993 Feb;60(1):19-29. doi: 10.1017/s002202990002731x.
In the present study newly calved cows were tentatively classified as moderate and severe responders to experimentally induced Escherichia coli mastitis based upon the reactive oxygen species (ROS)-generating capacity of their blood neutrophils before infection. The groups differed in blood and milk composition prior to infection. This initial classification was supported by the corresponding variation in clinical symptoms and in the changes in milk production and composition measured during mastitis. Responses of newly calved cows to Esch. coli challenge varied from mild to severe symptoms of inflammation in infected glands and differed in the intensity of systemic disturbances and general illness. Losses in milk yield and compositional changes were most pronounced in inflamed glands and in severe responders. In inflamed glands milk yield and composition did not return to preinfection level in either moderate or severe responders. The yields of lactose, alpha-lactalbumin, casein and fat followed the same pattern as milk yield. It is concluded that the severe and long lasting systemic disturbances observed in severe responders can be ascribed to absorption of endotoxin from infected glands into circulation, indicating the important role of endotoxin in the pathology of coliform mastitis in periparturient cows. Evaluation of the ROS-generating capacity of blood neutrophils and blood and milk composition before infection might help to predict the cow's sensitivity to Esch. coli mastitis.
在本研究中，根据新产奶牛感染前血液中性粒细胞产生活性氧（ROS）的能力，将其初步分为对实验性诱导的大肠杆菌乳腺炎的中度和重度反应者。两组在感染前的血液和乳汁成分存在差异。这种初步分类得到了乳腺炎期间临床症状以及产奶量和乳汁成分变化的相应差异的支持。新产奶牛对大肠杆菌攻击的反应在受感染乳腺中表现为从轻度到重度的炎症症状，全身紊乱和一般疾病的严重程度也有所不同。产奶量损失和成分变化在发炎的乳腺和重度反应者中最为明显。在发炎的乳腺中，中度和重度反应者的产奶量和乳汁成分均未恢复到感染前水平。乳糖、α-乳白蛋白、酪蛋白和脂肪的产量与产奶量遵循相同模式。得出的结论是，在重度反应者中观察到的严重且持久的全身紊乱可归因于内毒素从受感染乳腺吸收进入循环，这表明内毒素在围产期奶牛大肠埃希菌乳腺炎病理过程中起重要作用。评估感染前血液中性粒细胞产生ROS的能力以及血液和乳汁成分可能有助于预测奶牛对大肠杆菌乳腺炎的敏感性。
