Lew A E, Bock R E, Croft J M, Minchin C M, Kingston T G, Dalgliesh R J
Animal Research Institute, Queensland Department of Primary Industries, Moorooka.
Aust Vet J. 1997 Aug;75(8):575-8. doi: 10.1111/j.1751-0813.1997.tb14197.x.
To determine whether particular genotypes of Babesia bovis were common to field isolates obtained from cattle properties in Queensland where the B bovis vaccine had apparently failed.
A comparative study of polymerase chain reaction genotypes in different populations of B bovis.
Two polymerase chain reaction assays were applied to analyse DNA extracts of B bovis vaccine (K, T and Dixie strains) and 27 field isolates from 24 properties where disease outbreaks had occurred despite the use of the vaccine. To evaluate the stability of the genotypes identified, 11 of the field isolates were inoculated into experimental cattle that had either been previously vaccinated with T strain or not vaccinated.
No particular genotype of B bovis was responsible for the problems observed in previously vaccinated herds. None of the isolates had genotypes identical to the vaccine strains used. No geographic trends among the genotypes were observed. Isolates that originated from the same property also had different genotypes. Blood passage of the 11 field isolates in either previously vaccinated or nonvaccinated cattle did not alter the original genotype.
No particular genotypes identified by the Bv80 and BvVA1 polymerase chain reaction assays could be associated with vaccine failures.
确定从昆士兰州牛场获取的、牛巴贝斯虫疫苗显然失效的野外分离株中是否存在特定基因型。
对不同牛巴贝斯虫群体的聚合酶链反应基因型进行比较研究。
应用两种聚合酶链反应分析方法，分析牛巴贝斯虫疫苗（K、T和迪克西菌株）以及来自24个牧场的27株野外分离株的DNA提取物，这些牧场尽管使用了疫苗仍发生了疾病暴发。为评估所鉴定基因型的稳定性，将11株野外分离株接种到先前接种过T株疫苗或未接种过疫苗的实验牛中。
牛巴贝斯虫的特定基因型并非导致先前接种疫苗牛群中所观察到问题的原因。所有分离株均无与所用疫苗株相同的基因型。未观察到基因型的地理分布趋势。来自同一牧场的分离株也具有不同的基因型。11株野外分离株在先前接种过疫苗或未接种过疫苗的牛中传代，并未改变其原始基因型。
通过Bv80和BvVA1聚合酶链反应分析鉴定出的特定基因型与疫苗失效无关。
