Vandeputte-Van Messom G V, Burvenich C
Department of Veterinary Physiology, Faculty of Veterinary Medicine, University of Ghent, Belgium.
J Dairy Sci. 1993 Dec;76(12):3727-41. doi: 10.3168/jds.s0022-0302(93)77715-2.
The potential protective and therapeutic effects of bST during coliform mastitis in periparturient cows were evaluated. In a first study, 19 cows, classified as moderate or severe responders based on the respiratory burst activity of blood neutrophils, were treated with recombinant bST or vehicle 48 h after intramammary inoculation of Escherichia coli. Clinical status and changes in milk production and composition were compared in the four groups. In a second study, 8 cows received bST or vehicle 7 d before bacterial challenge. During mastitis, losses in milk production and compositional changes were most pronounced in infected glands and in severe responders. Milk production of bST cows recovered better than that of placebo cows. Recovery of milk components was accelerated in severe responders treated with bST, but not in moderate responders. Pretreatment of severe responders with bST enhanced milk production before infection, protected the mammary glands from excessive loss of milk during the subsequently induced coliform mastitis, and accelerated normalization of milk composition. In conclusion, the beneficial effects of bST upon normalization of milk production and composition in periparturient cows suffering from coliform mastitis seem to be restricted to the severe responders. In severe responders that had been treated with bST, changes observed during mastitis resembled those in moderate responders treated with the placebo.
评估了牛生长激素（bST）在围产期奶牛大肠杆菌性乳腺炎期间的潜在保护和治疗作用。在第一项研究中，根据血液中性粒细胞的呼吸爆发活性将19头奶牛分为中度或重度反应者，在乳房内接种大肠杆菌48小时后，用重组bST或赋形剂进行治疗。比较了四组的临床状况以及产奶量和乳汁成分的变化。在第二项研究中，8头奶牛在细菌攻击前7天接受bST或赋形剂。在乳腺炎期间，感染腺体和重度反应者的产奶量损失和成分变化最为明显。接受bST治疗的奶牛产奶量恢复情况优于接受安慰剂治疗的奶牛。用bST治疗的重度反应者乳汁成分的恢复加快，但中度反应者没有。对重度反应者在感染前用bST进行预处理可提高产奶量，保护乳腺在随后诱发的大肠杆菌性乳腺炎期间不致过度损失乳汁，并加速乳汁成分的正常化。总之，bST对患有大肠杆菌性乳腺炎的围产期奶牛产奶量和乳汁成分正常化的有益作用似乎仅限于重度反应者。在用bST治疗的重度反应者中，乳腺炎期间观察到的变化类似于用安慰剂治疗的中度反应者。
