Tomita G M, Ray C H, Nickerson S C, Owens W E, Gallo G F
Hill Farm Research Station, Louisiana Agricultural Experiment Station, Louisiana State University Agricultural Center, Homer 71040, USA.
J Dairy Sci. 2000 Oct;83(10):2276-81. doi: 10.3168/jds.S0022-0302(00)75112-5.
The efficacy of two commercially available Escherichia coli J5 bacterins was investigated. Jersey cows were randomly assigned to one of three treatment groups: 1) unvaccinated controls, 2) vaccinated with J.VAC (Merial Limited, Athens, GA), and 3) vaccinated with J5 bacterin. All cows were vaccinated at drying off and at 2 wk before anticipated calving. Cows that were vaccinated with the J5 bacterin also received a third immunization at calving. One quarter of each cow was challenged with approximately 64 cfu of E. coli at 14 to 30 d postcalving. Immunization by either vaccine did not influence the severity of coliform mastitis; however, the mean number of colony-forming units of E. coli recovered from challenged quarters was significantly lower for immunized cows than for control cows at 144 h postchallenge. Serum and mammary secretion immunoglobulin (Ig)G, IgG1, and IgG2 titers against E. coli J5 whole-cell antigens were enhanced in vaccinated cows. Serum and mammary secretion IgM were not different among treatment groups. Somatic cell counts in milk from challenged quarters, rectal temperatures, and the clinical status of cows following intramammary challenge were not different among treatment groups.
对两种市售的大肠杆菌J5菌苗的效力进行了研究。泽西奶牛被随机分配到三个治疗组之一：1）未接种疫苗的对照组，2）接种J.VAC（梅里亚有限公司，佐治亚州雅典），3）接种J5菌苗。所有奶牛在干奶期和预期产犊前2周进行接种。接种J5菌苗的奶牛在产犊时还接受了第三次免疫。每头奶牛的四分之一在产后14至30天用约64 cfu的大肠杆菌进行攻毒。两种疫苗免疫均不影响大肠埃希菌性乳腺炎的严重程度；然而，在攻毒后144小时，从攻毒乳腺中回收的大肠杆菌菌落形成单位的平均数，免疫奶牛显著低于对照奶牛。接种疫苗的奶牛血清和乳腺分泌物中针对大肠杆菌J5全细胞抗原的免疫球蛋白（Ig）G、IgG1和IgG2滴度升高。治疗组之间血清和乳腺分泌物IgM无差异。攻毒乳腺的牛奶中的体细胞计数、直肠温度以及乳房内攻毒后奶牛的临床状况在治疗组之间无差异。
