Open Access
Research (Published online: 08-06-2017)
7. Using real-time polymerase chain reaction as an alternative rapid method for enumeration of colony count in live Brucella vaccines
Waleed S. Shell, Mahmoud L. Sayed, A. A. Samy, Ghada Mohamed Al-Sadek, Gina Mohamed Mohamed Abd El-Hamid and Abde Hakam M. Ali
Veterinary World, 10(6): 610-615

Waleed S. Shell: Central Laboratory for Evaluation of Veterinary Biologics, Cairo, Abbasia, Egypt.
Mahmoud L. Sayed: Central Laboratory for Evaluation of Veterinary Biologics, Cairo, Abbasia, Egypt.
A. A. Samy: Department of Microbiology and Immunology, National Research Center, Egypt.
Ghada Mohamed Al-Sadek: Central Laboratory for Evaluation of Veterinary Biologics, Cairo, Abbasia, Egypt.
Gina Mohamed Mohamed Abd El-Hamid: Central Laboratory for Evaluation of Veterinary Biologics, Cairo, Abbasia, Egypt.
Abde Hakam M. Ali: Central Laboratory for Evaluation of Veterinary Biologics, Cairo, Abbasia, Egypt.

doi: 10.14202/vetworld.2017.610-615

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Article history: Received: 28-01-2017, Accepted: 18-04-2017, Published online: 08-06-2017

Corresponding author: Waleed S. Shell


Citation: Shell WS, Sayed ML, Samy AA, Al-Sadek GM, El-Hamid GMMA, Ali AHM (2017) Using real-time polymerase chain reaction as an alternative rapid method for enumeration of colony count in live Brucella vaccines, Veterinary World, 10(6): 610-615.

Aim: Brucellosis is a major bacterial zoonosis of global importance affecting a range of animal species and man worldwide. It has economic, public health, and bio-risk importance. Control and prevention of animal brucellosis mainly depend on accurate diagnostic tools and implementation of effective and safe animal vaccination program. There are three types of animal Brucella live vaccines - Brucella melitensis Rev-1 vaccine, Brucella abortus S19, and B. abortus RB51. Evaluation of these vaccines depends mainly on enumeration of Brucella viable count. At present, used colony count method is time consuming, costly and requires especial skills. Hence, the aim of this study is to use and standardize real-time polymerase chain reaction (RT-PCR) as an alternative, quantitative, sensitive, and rapid method to detect the colony count of Brucella in live Brucella vaccine.

Materials and Methods: Four batches of different live Brucella vaccines were evaluated using of conventional bacterial count and RT-quantitative PCR (RT-qPCR) using BSCP31 gene specific primers and probe. Standard curve was generated from DNA template extracted from 10-fold serial dilution of living B. abortus RB51 vaccine to evaluate the sensitivity of RT-qPCR.

Results: Results revealed that three batches of living Brucella vaccines were acceptable for Brucella colony count when traditional bacterial enumeration method was used. Results of RT-qPCR were identical to that of conventional bacterial count.

Conclusion: Results concluded that RT-qPCR was relatively sensitive compared to traditional bacterial colony count of these vaccines.

Keywords: Brucella, colony count, RB51, Rev-1, real-time polymerase chain reaction, S19, vaccines.


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