González R N, Cullor J S, Jasper D E, Farver T B, Bushnell R B, Oliver M N
Department of Clinical Pathology, School of Veterinary Medicine, University of California, Davis 95616.
Can J Vet Res. 1989 Jul;53(3):301-5.
A prospective cohort study was undertaken in two commercial California dairies. The treatment group, 246 cows, received three doses of a whole cell bacterin of J5 Escherichia coli (mutant of E. coli O111:B4) plus Freund's incomplete adjuvant vaccine (two in the dry period and one after calving) while 240 unvaccinated cows served as controls. Thirty-five cases of clinical coliform mastitis were diagnosed, six in vaccinated cows and 29 in unvaccinated cows. Bacteria isolated from the clinical cases included 15 E. coli five Klebsiella pneumoniae, three K. oxytoca, three K. ozaenae, five Enterobacter aerogenes, three Serratia marcescens and one Serratia spp. Four control cows were culled, three of them because of chronic coliform mastitis and one because of postcoliform infection agalactia. Incidence rate of clinical gram-negative mastitis was 2.57% in vaccinated cows and 12.77% in unvaccinated cows. The estimated risk ratio, the measure of risk of having clinical gram-negative mastitis for vaccinated cows to unvaccinated cows, was 0.20 (p less than 0.005), indicating a strong relationship between vaccination and lack of clinical gram-negative mastitis. The results of this trial indicate that the administration of the E. coli J5 vaccine is protective against natural challenge to gram-negative bacteria, and reduces the incidence of clinical gram-negative mastitis in dairy cows during the first three months of lactation.
在加利福尼亚州的两家商业奶牛场进行了一项前瞻性队列研究。治疗组有246头奶牛，接受了三剂J5大肠杆菌（大肠杆菌O111:B4的突变体）全细胞菌苗加弗氏不完全佐剂疫苗（干奶期两剂，产犊后一剂），而240头未接种疫苗的奶牛作为对照。诊断出35例临床大肠埃希菌性乳腺炎病例，接种疫苗的奶牛中有6例，未接种疫苗的奶牛中有29例。从临床病例中分离出的细菌包括15株大肠杆菌、5株肺炎克雷伯菌、3株产酸克雷伯菌、3株臭鼻克雷伯菌、5株产气肠杆菌、3株黏质沙雷菌和1株沙雷菌属。4头对照奶牛被淘汰，其中3头是因为慢性大肠埃希菌性乳腺炎，1头是因为大肠埃希菌感染后无乳。接种疫苗的奶牛临床革兰氏阴性乳腺炎发病率为2.57%，未接种疫苗的奶牛为12.77%。估计风险比，即接种疫苗的奶牛与未接种疫苗的奶牛患临床革兰氏阴性乳腺炎风险的衡量指标，为0.20（p小于0.005），表明接种疫苗与缺乏临床革兰氏阴性乳腺炎之间存在密切关系。该试验结果表明，接种大肠杆菌J5疫苗可预防革兰氏阴性菌的自然感染，并降低泌乳期前三个月奶牛临床革兰氏阴性乳腺炎的发病率。
