目的  建立标准化的布鲁菌Tb噬菌体效价噬斑测定方法。方法  通过比较单层琼脂平板法与双层琼脂平板法，对宿主菌接种浓度、吸附时间及培养时间等参数，标准化布鲁菌Tb噬菌体效价测定方法，并分析其精密性。结果  虽然两种方法测定的噬菌体结果无差别，但双层琼脂平板法的噬斑背景背景更清晰，易于结果观察。经优化后确定布鲁菌Tb噬菌体效价测定条件：宿主菌的最适接种浓度为1.0×10⁹ ml^-1，宿主菌与噬菌体混合后不需吸附，培养3~5 d后进行噬菌斑计数。建立的标准检测方法具有较好的精密性。结论  建立了布鲁菌Tb噬菌体效价噬菌斑测定方法，为布鲁菌Tb噬菌体及布鲁菌活疫苗质量控制奠定了基础。

Objective  To establish a plaque assay method in determination of phage Tb titer for Brucella. Methods  Single-layer agar plate method and double-layer agar plate method were compared. A plaque assay method for determination of titer of phage for Brucella was developed by optimizing the concentration of Brucella cells for inoculation, adsorption time and incubation time. Precision for the developed method was estimated. Results  Although the plaque titer results by both methods were similar,the plaque background of double-layer  agar plate method was more clear and easy to observe.The conditions of optimized method for Brucella phage Tb titer measurement were determined.The optimal Brucella cell concentration for inoculation was 1.0×10⁹ ml^-1.Adsorption after the mixture of host and phage was not necessary.Plaques were counted after 3-5 d culture.It showed a good precision for the developed method. Conclusion   A plaque assay method in determination of phage Tb titer for Brucella and brucellosis vaccine.